text:
package edu.internet2.middleware.shibboleth.idp.session.impl;

import java.security.Principal;
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;

import javax.security.auth.Subject;

import edu.internet2.middleware.shibboleth.common.session.impl.AbstractSession;
import edu.internet2.middleware.shibboleth.idp.authn.UsernamePrincipal;
import edu.internet2.middleware.shibboleth.idp.session.AuthenticationMethodInformation;
import edu.internet2.middleware.shibboleth.idp.session.ServiceInformation;
import edu.internet2.middleware.shibboleth.idp.session.Session;

/** Session information for user logged into the IdP. */
public class SessionImpl extends AbstractSession implements Session {

    /** Serial version UID. */
    private static final long serialVersionUID = 2927868242208211623L;

    /** Secret key associated with the session. */
    private byte[] sessionSecret;

    /** The list of methods used to authenticate the user. */
    private Map<String, AuthenticationMethodInformation> authnMethods;

    /** The list of services to which the user has logged in. */
    private Map<String, ServiceInformation> servicesInformation;

    /**
     * Constructor.
     *
     * @param sessionId ID of the session
     * @param secret a secret to associate with the session
     * @param timeout inactivity timeout for the session in milliseconds
     */
    public SessionImpl(String sessionId, byte[] secret, long timeout) {
        super(sessionId, timeout);

        sessionSecret = secret;
        authnMethods = new /*Concurrent*/HashMap<String, AuthenticationMethodInformation>(2);
        servicesInformation = new /*Concurrent*/HashMap<String, ServiceInformation>(2);

        /* BLITZ patch (added) : External storage service support */
        indexes = new HashSet<String>();
        replicationCount = 0;
        changed = true;
        //

    }

    /** {@inheritDoc} */
    public /*synchronized*/ byte[] getSessionSecret() {
        return sessionSecret;
    }

    /** {@inheritDoc} */
    public /*synchronized*/ Map<String, AuthenticationMethodInformation> getAuthenticationMethods() {
        return Collections.unmodifiableMap(authnMethods);
    }

    /** {@inheritDoc} */
    public /*synchronized*/ Map<String, ServiceInformation> getServicesInformation() {
        return Collections.unmodifiableMap(servicesInformation);
    }

    /**
     * Gets the service information for the given entity ID.
     *
     * @param entityId entity ID to retrieve the service information for
     *
     * @return the service information or null
     */
    public /*synchronized*/ ServiceInformation getServiceInformation(String entityId) {
        return servicesInformation.get(entityId);
    }

    /**
     * This method will return the first, in an unordered list of principal names registered with the {@link javax.security.auth.Subject} of
     * the session. If one or more {@link UsernamePrincipal} principals is registered with the subject the returned
     * value will be the string form of one of those.
     *
     * {@inheritDoc}
     */
    public /*synchronized*/ String getPrincipalName() {
        Subject subject = getSubject();

        Set<? extends Principal> principals = subject.getPrincipals(UsernamePrincipal.class);
        if (principals == null || principals.isEmpty()) {
            principals = subject.getPrincipals();
        }

        if (principals == null || principals.isEmpty()) {
            return null;
        }

        return principals.iterator().next().getName();
    }

    public /*synchronized*/ void addServicesInformation(String key, ServiceInformation value) {
        servicesInformation.put(key, value);
        changed = true;
    }
    public /*synchronized*/ void addAuthenticationMethods(String key, AuthenticationMethodInformation value){
        authnMethods.put(key, value);
        changed = true;
    }
    public /*synchronized*/ void remoteAuthenticationMethods(String key){
        authnMethods.remove(key);
        changed = true;
    }

    /* BLITZ patch (added) : External storage service support */

    private int replicationCount;
    private Set<String> indexes;

    public /*synchronized*/ boolean isChanged() {
        return changed;
    }

    public /*synchronized*/ int getReplicationCount() {
        return replicationCount;
    }

    public /*synchronized*/ void markAsReplicated(){
        this.changed = false;
        this.replicationCount++;
        indexes.clear();
    }

    public /*synchronized*/ Set<String> getIndexes() {
        return Collections.unmodifiableSet(indexes);
    }

    public /*synchronized*/ boolean addIndex(String index) {
        return (index != null && indexes.add(index));
    }

}


text:
Monumental wall map of the United States by Osgood Carleton
An unusually voluminous record of an 18th-century Bristol County, Massachusetts surveyor
Late 18th-century manuscript plan of Boston, after Osgood Carleton
Spectacular family tree for the Mayhews of Martha's Vineyard
Osgood Carleton, A New Map of the UNITED STATES, OF AMERICA Including part of Louisiana Drawn from the latest Authorities Revised and corrected by OSGOOD CARLETON. Esqr. Teacher of Mathematics BOSTON. Boston: John Sullivan Junr., 1806.
Engraving on nine sheets joined, 48"h x 55"w at neat line plus margins, wash and outline color. Expertly restored: removed from 20th-century linen, mended as needed, small areas of loss reinstated in facsimile, traces of original color retouched to style.
A monumental wall map of the United States by Osgood Carleton, much enlarged and greatly updated to reflect political developments and advances in geographic knowledge. A great rarity, known in only 10 or 11 examples, most in American institutions.
Carleton's first attempt at a wall map of the country appeared in 1791 as The United States of America, Laid Down from the Best Authorities. Over the next 15 years the face of the young nation changed dramatically, and geographic knowledge progressed greatly, notably advanced by the two postal road maps of Abraham Bradley (1796 and 1804) and the wall-map of the United States by Aaron Arrowsmith (1796 and later). Publication of the momentous findings of the Lewis & Clark expedition remained well in the future.
In creating this new map of 1806, Carleton clearly used as his starting point the 1802 edition of Arrowsmith's map. The coverage of the two maps is essentially identical, including the entire United States east of the Mississippi, much of the recently-acquired Louisiana Territory, and adjacent areas of British Canada and Spanish East and West Florida. Carleton also for the most part followed Arrowsmith's cartographic detail, as may be seen for example in the depiction of the Great Lakes, the pictorial treatment of the Appalachians, and the hachuring indicating highlands in Michigan and along the Mississippi.
However Carleton diverges from Arrowsmith in any number of important ways. The most obvious are the additions of the Northwest Territory (organized 1787), Indiana Territory (1800), and the State of Ohio (acceded 1803). Whereas Arrowsmith depicted a hypertrophied Georgia extending to the Mississippi, Carleton has carved out an oddly-shaped "Mississippi Territory" and, to the north of it, a mammoth, unnamed entity occupied by the Creeks and a number of competing land companies. The geographic treatment of this region, now comprising Georgia, Florida, Alabama and Mississippi, also diverges greatly from that of Arrowsmith. Finally, Carleton's treatment of Maine is far more detailed, and in place of Arrowsmith's undefined international boundary he offers an aggressive interpretation extending the U.S.-Canada border to within miles of the St. Lawrence.
The map also features two tables, neither present on the Arrowsmith. One at top lists ports of entry for foreign passengers and commerce, organized by state, while that below provides statistical data for each of the states and territories.
Carleton's map is recorded in two states, the first most readily distinguished by the absence of the copyright line just above the lower border.
Osgood Carleton and John Sullivan
"As a commercial mapmaker not associated with the printing or engraving trades, Carleton stands apart as one of the first professional American cartographers" (Bosse). Osgood Carleton (1741-1816) trained with the British army, learning surveying from John Henry Bastide, chief British engineer at the siege of Louisbourg in 1758, before spending several years at sea. After service in the Revolutionary War, he settled in Boston, where he established himself as a surveyor, mapmaker and teacher of mathematics, surveying, navigation and astronomy.
Carleton was at the center of mapmaking and map publishing in Boston from the 1780s to about 1810. Much of his work was published in association with John Norman (1748-1817), an English-born engraver, mapmaker and publisher and his son, William (d.1807). The partners put Boston firmly at the forefront of innovative American cartographic publishing in that period, producing wall-maps of the United States, Massachusetts, Maine and Boston; assisting in Mathew Clark's A complete set of charts of the coast of America from Cape Breton to the entrance of the Gulph of Mexico (1790); and producing a sequence of sea-atlases, including John's The American Pilot (1791) and William's A pilot for the West-Indies (1795) and South-American Pilot (1803), as well as numerous single-sheet maps and charts and numbers of bookplates.
John Sullivan Jr. is but a footnote in cartographic history. He appears briefly in Boston directories, recorded as a trader operating a counting room on Market Street from 1805 to 1807, but is not found before or after, nor is he otherwise known for map work. Interestingly, although Carleton is best known as a mapmaker and teacher of navigation, when he went bankrupt in 1803, he was recorded as a trader, and this career may be how the two met.
The likelihood is that this map of the United States was engraved by one of the Normans, more likely John, Carleton and the Normans seeming to have continued their co-operation from about 1803 after the hiatus induced by a debacle involving a failed project to produce official maps of Massachusetts and Maine.
Publication of the map
Sullivan first announced his intention to publish the map in a printed prospectus dated June 1804. Several months later he made a more public announcement:
"PROPOSAL FOR Publishing, by Subscription, a new, correct, and elegant MAP of the United States of America; Including part of Louisiana. — Compiled from the latest Observations, and most correct Surveys; revised and corrected by OSGOOD CARLTON [sic] … The MAP, now offered, is on a larger scale, and presumed to be more correct and perfect than any production of the kind heretofore presented to the American Republic. The Publisher has [sic] been negligent of trouble, and careless of expence, in collecting new, and collating old materials; — and he is sanguine in the belief, that the correctness of the projections, and the style of execution, are superior to those of any other MAP, or CHART, ever delineated, or published in the United States. … The price to Subscribers will be Four Dollars, to be paid on receipt of the MAP, to non-Subscribers, the price will be Six dollars. …" (Boston Independent Chronicle, November 26, 1804).
The project was much delayed, but eventually Sullivan filed for copyright in the Massachusetts District Court on April 28, 1806. Two weeks later he
"respectfully informs his friends, and patrons generally, that the Map of the United States is now completed, and will be ready to be delivered … in 14 days. — And in pursuing the great object of making this Map correct … feels confident, that it will be found superior to any Map heretofore published of the American States. … The Map is exhibited for review at the Publisher's counting room … where the subscribers will be received at 6 dollars in sheets, until the former subscribers are supplied; when the subscription will be closed, and the price advanced to 8 dols. and not sold under that price; it will then be the cheapest Map of any one before published in America. Arrangements are made to put them on cloth and rollers, and folded in portable cases, at a reasonable price" (Boston Independent Chronicle, May 8, 1806).
We will never know for sure why the price went from four to six dollars between 1804 and 1806, but the most likely explanation is that, as was often the case with ambitious mapping projects, Sullivan's costs far outweighed his original projections.
Rarity and references
Most wall maps from this early period of American mapmaking are rare, and this map is no exception. Despite being widely advertised, the map seems to have had only limited circulation, if surviving examples are a reliable guide, with ten or fewer examples located across institutional and private collections. I know of only two others having appeared on the antiquarian market, one offered by the Philadelphia Print Shop in 1985, and another purchased by David Rumsey in the 2000s.
Rumsey #5801. OCLC #9487507 (Brown, Marquette County Historical, NYPL and Watertown (Mass.) Free Public Library, though this last is a ghost) and #45208448 (Connecticut Historical, Harvard, Indiana Historical Society, NYPL again, Yale). Other examples are held by the Library of Congress (though the map is not in Phillips, Maps of America), Stanford (the Rumsey copy), and a private collection in the Midwest.
For more on Osgood Carleton see David Bosse, "Osgood Carleton, Mathematical Practitioner of Boston." Proceedings of the Massachusetts Historical Society, Third Series, vol. 107 (1995), pp. 141-164.

redpajama_set_name: RedPajamaCommonCrawl


Free and Easy! If you will use iGive.com to buy your office supplies from your regular online supplier they will donate a percentage of that purchase to us at no additional cost to you! They donate from their advertising budget. Just register by clicking on the iGive.com icon and also down load their shopping window from the Shopping tab. The next time you shop for office supplies a donation will be given to us in your name.
If you use iGive.com as your workplace search engine, every time you make a new search they will donate 2¢ to our important programs. Now that's Free and Easy!
Our Partners make it possible to have supplies on hand; special formulas, medications, bandages, caging and bedding. Making a difference is simple, and our Partners like it because it feels great to make a difference all year. Log on today to be one of our dedicated partners who make monthly gifts that provide a consistent, reliable income stream, allowing us to focus on the important science of returning songbirds to the wild, and to keep those Happy Endings coming.
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Sydney Surveyors are consulting surveyors based in Sydney, who offer their GIS Data survey services throughout Sydney, New South Wales and Australia.
Our land surveying services include GIS Data Surveys. Councils and other statutory bodies are required to have an up to date register of their assets. We can collect the data for the register and record position, type, condition, etc for integration with the established GIS system being used by the customer.
We are able to carry out large scale data collection surveys for GIS systems. A GIS database gives you a better way to easily manage, reuse, share, and analyze your survey data, saving you time, money, and resources.
Because GIS software solutions are interoperable with the many data formats used in the field and office, you can deliver your data in the format required by your clients while maintaining the data's core integrity.
For more information regarding our GIS data survey services, contact Sydney Surveyors today.


In the midst of the political chaos in which the world develops, the numinous defense of dominant economic interests, growing inequality, perennial social challenge, the threats of global warming and the scarcity of natural resources, this movement supposes a breath of fresh air and hope in another form of social and economic coexistence.
The market for these environmentally-focused bonds appears to be developing rapidly, with money managers jumping in to purchase them.
Green bonds may play a game-changing role to back this large-scale requirement of global investments in clean energy.
Green crowdfunding is fast emerging as an innovative practice to support startups and enterprises engaged in the development of sustainable products and services.
Impact investing in conservation is one of the most effective ways to tackle the existing global deficit in conservation finance.
Is self-interest a constant and powerful force to work against the changes we need to bring about real justice in our society? Ron Schultz examines on Talkback.
A robust dialog gets going between NGOs and corporations at a major global conference. Ron Schultz reports on Talkback.
Can business keep on its toes by telling more to understand more? Carol Sanford postulates what's in store for the new year.


text:
Creative careers are more varied than ever today. Read one art director's story on how he ended up at the global leader in live entertainment.
Miami Ad School art direction graduate GT Smith toasts his new career on the rooftop of Live Nation headquarters in New York City.
After earning a degree in film and a series of jobs that were ultimately unfulfilling, GT found Miami Ad School Wynwood by simply driving down the street. That discovery, and a snazzy bomber jacket, set him on a path to a new career, in a new city, doing things he'd never dreamed.
Pippa Seichrist: So, what were you doing before you came to Miami Ad School?
GT Smith: I worked for a catering company in Miami packing trucks and serving events.
PS: How did you hear about the school?
GTS: I would see the new—and very pink—Miami Ad School building in Wynwood, under construction, on my route back to the catering warehouse and said to myself, "People actually go there to learn to produce advertisements?" It seemed like a strange career to have. Then, suddenly, it was what I wanted.
PS: How did you land the job at Live Nation?
GTS: It was all thanks to Miami Ad School's portfolio reviews. I met my future creative director at one in New York in 2016.
PS: Besides having a great portfolio, did you do anything interesting to catch their attention?
GTS: I demonstrated an ability to concisely and clearly speak about my work, and I was able show my aptitude with market research, besides having work that was visually impactful and interesting. It helped my future creative director and I were wearing the exact same bomber jacket.
A great portfolio is the first step to landing a career in any creative field, and what we specialize in at Miami Ad School. Here are three pieces from GT's book that set his work apart. You can see the rest of GT's portfolio here.
PS: Tell us an interesting story about one of the pieces that you've worked on at Live Nation?
GTS: My Austin City Limits mural for American Express last year was an incredibly fun thing to work on and was a lesson in pitching. I not only helped concept the activation, but I was also tasked with illustrating a mural for the photo booth portion of it, a crucial part of a very high profile activation. Originally they went with a far less interesting concept, which was essentially just a skyline of Austin with some bats flying around. But, I put all my effort into making the photo booth concept an offer they couldn't refuse. They didn't!
GT's American Express photo booth at the 2017 Austin City Limits Music Festival.
PS: Tell me about a favorite teacher and the influence they had on you.
GTS: Theo Rudnak (Emerging Media Coach, Miami Ad School @ Portfolio Center in Atlanta) was my favorite instructor because he teaches with genuine passion and curiosity for his craft. He is as interested in learning from his students as he is excited to share his knowledge with them. His advice and teachings have improved my speed, aptitude and finish on absolutely everything I design and illustrate. Taking one quarter of his class is as useful as attending art school for an entire year, and every time I finish something I think of how much he helped me in such a short time.
"Thank you GT. We're kindred spirits for sure. It was my good fortune to have GT placed in my class. He never wasted an opportunity. He knew how to argue effectively, he listened to others and responded respectfully. What he did in class mattered. Not just to me but for other students in a way that helped all of us to become better versions of ourselves."
–Theo Rudnak
PS: For those who may not know, what is Live Nation all about? What's your official job title there?
GTS: I am an art director and I work for our internal creative department. We acquire new business to sponsor specific areas of our many concerts and festivals and handle existing business requests. Live Nation puts on some of the biggest festivals and concerts in the world, and is essentially trying to find authentic ways brands can advertise their products. We creatives do everything: write manifestos, concept, design and pitch decks, illustrate concepts, edit video, design in 3D, everything.
PS: Describe what exactly it is you do at Live Nation—what kinds of things do you work on?
GTS: I work on existing business and new business pitches. I illustrate and design a lot of visual concepts and I strategize what ways brands can play with us. We make a lot of decks, but I end up producing a lot of outdoor stuff for concerts as well as video to print media.
PS: What's your favorite thing about having a creative career?
GTS: I like that I am allowed to be strange and eccentric by virtue of my career, but also I am allowed the rare privilege of selling weird ideas to traditional brands. There is no greater pleasure in the world than getting a buttoned up brand to do something exceptionally strange, especially when you have good strategy behind it.
Where will a creative career will take you? Learn how to apply.


What does it mean to be a Quaker parent?
Here you can find reflections on Quakerism and the family as well as resources, courses and where to find a Quaker meeting with children's activities near you.
Use the find a Quaker meeting online tool to search for a meeting near you. The closest meetings to the location that you have selected are listed and have symbols that guide you to find meetings that has activities for children.
This is an online facebook discussion group for Quaker parents. Friends can request to join the group and then be part of the discussions.
An opportunity for Quakers who are parents to come together and explore our values as Quakers and the highs and lows of parenting. It takes time to think about how Quaker parents are or might be supported and nourished within their homes, meetings and in the wider world. Sessions include sharing, listening, reflection and input.
The course takes place at Woodbrooke every 3 years and runs with a parallel programme for young people.
Meet informally at lunchtime with other Quaker parents to share and learn or just have a chat about things that you find important in your experience as a Quaker parent.
Find out when and where it will take place in the Yearly Meeting events listing.


Grapes wallpapers for your iphone. If you want to download grapes photo for your desktop, please download this wallpapers below and click set as desktop background. You can share this wallpaper in social networks, we will be very grateful to you.
Total 706 views. Posted by Eamon Aspole from 29-04-2016, 18:25.


We have found 2 profiles for Randy Potarf in McDonald, MO.
Summary: On November 17, 2016, McDonald County Law Enforcement arrested 33-year-old Randy Leon Potarf in McDonald, Missouri. He is 6' 3" tall, weighs 172 lbs and has green eyes. All suspects are presumed innocent until proven guilty. Information about upcoming court dates for Potarf may be obtained from one of the following law enforcement or prosecuting agencies: McDonald County Law Enforcement.
Summary: Arrested on July 03, 2015 was Randy L Potarf. The 32-year-old Potarf was arrested by McDonald County Law Enforcement. He is 6' 3" tall, weighs 172 lbs and has green eyes. Bond was set at unknown amount for the charge because Potarf is presumed innocent until proven guilty. Police agencies listed here may assist with more information including court dates: McDonald County Law Enforcement.


text:
guest-chefs-savor-kitchen-takevover.jpg
Brian Oh
Industry Takeover Night
Guest Chefs Savor Kitchen Takeover
December 10, 2013 | Industry News
The downside of being a busy, profitable chef is there's no time to eat at restaurants led by other noteworthy chefs.
That problem is what inspired Mike Isabella, chef-owner of Graffiato and G's Sandwich Shop in Washington D.C., to launch a guest-chef series at both eateries.
"I like to hang out with my friends, and I like to eat and have good food," says Isabella. "That's what I do for a living." By bringing guest chefs into his kitchen to cook for customers, he can see and taste what his culinary friends are cooking up.
In January 2013, he introduced a guest-chef series called "Industry Takeover Night" at his Italian-themed restaurant Graffiato, which opened in 2011 in Washington's Chinatown neighborhood. It occurs on the first Monday of each month, on what is historically a slow day in restaurants.
"I leave, they come in and take over the kitchen," he explains. Customers pay $10 in cash at the door, with half of that money going to a charity of the chefs' choice. Often the chefs are flown in from other cities.
In December 2013, guest chefs included Greg Basalla, chef de cuisine at Boqueria in Washington, D.C.; Josh Brown, executive chef at Level in Annapolis, Maryland; Andrew Fox, Level's owner and bartender; Eli Kirshtein, executive chef/partner at the forthcoming The Luminary in Atlanta; and Andrea Litvin, executive pastry chef at The Spence in Atlanta. An additional $5 gets the customer a drink from the guest mixologist, or a glass of beer or wine. Proceeds from the December event went to Martha's Table, providing food, education, and clothing to low-income families.
"People come early just to get in line. Otherwise you can't get in," says Isabella. "A lot of people don't get to travel to Kentucky or Vegas and won't ever have the chance to try their food."
At G, a sandwich shop open since the summer in the nation's capital, a guest chef develops a signature sandwich only available during a particular month. In November, the first month of the guest-chef series, chef Scott Drewno introduced "The Drewno," featuring housemade kielbasa, Italian beef, and sauerkraut. Drewno, a good friend of Isabella's, is a chef at The Source, a Wolfgang Puck Asian-fusion eatery tucked into D.C.'s Newseum. "It's a sandwich he likes to eat when he has a couple of drinks," says Isabella. "It has been selling so well we are keeping it on the menu."
Guest-chef series are popping up across the country in an effort to introduce diners to other restaurants and also feed a chef's need to learn techniques and innovation from other chefs.
Eric Jorgensen, chef de cuisine at Little Market Brasserie in Chicago, launched a guest-chef series—with a charitable mission—in September. The "Melts for Meals" year-long program rolls out a different grilled-cheese sandwich each month, developed by Chicago chefs like Andrew Zimmerman of Sepia and Mark Steur of the year-old Carriage House. "We wanted to do something to give back," says Jorgensen. "The all-day grilled cheese is a big hit over here, especially during lunch." One dollar from each sandwich ordered goes to a local Meals on Wheels chapter.
Although it's attracting high-profile chefs, "Melts for Meals" is not about being famous, explains Jorgensen. "I looked for chefs whose food I'm already eating and chefs I already like," he says. "It's a lot of fun for us to see what other chefs' ideal grilled-cheese sandwich would be."
In November the sandwich creation came from Cory Morris, sous chef under Jose Garces at Mercat a la Planxa in Chicago. Serrano ham, rosemary-peach jam, truffle butter, and Manchego cheese are piled onto brioche bread. "It's almost like a meat and cheese platter," says Jorgensen.
To get the word out, Jorgensen recruited a local publicity firm to handle outreach to media, including bloggers with shorter lead times than print media. Attractive cards promoting the "Melt for Meal" program were also printed and placed on tables at Little Market Brasserie, "so the customer doesn't have to ask," says Jorgensen.
Both Isabella and Jorgensen tapped into their culinary network to find chefs willing to participate. "I started by emailing everyone I knew in the industry," says Isabella, who then pitched the news himself to media, particularly bloggers. When Jorgensen started to contact chefs he was surprised that six committed right away, proof that the idea is a hit.
Other restaurants that have dabbled with guest-chef programs include Two in Chicago, which rolled out its Midwest-focused series just two months after opening in August of 2012. Guest chef Chris Marchino of Spiaggia developed two dishes: gnocchi stuffed with Medjol dates, ricotta, aged Gorgonzola, walnut, and sage; and porcetta with creamy polenta, pickled cauliflower, Calabrian peppers, and fennel pollen. Houston's Triniti Restaurant launched a guest-chef series in June with four set dates for an eight-course dinner designed by three visiting chefs. Tickets were limited to 22 diners at each and cost $75.
By Kristine Hansen
Inside the Kitchen of the Formidable Nyesha Arrington
Eric Ripert, José Andrés Create Scholarship in Honor of Anthony Bourdain


This time last year, I had the good fortune to spend a bit of time in Germany, Italy, and France. The trip was the perfect combination of "vacation" and "travel" - time on the beach and golf course balanced against the discovery of historic sites and the exploration of backstreets that don't see many tourists (and certainly not American tourists). I have long made a distinction between the terms "vacation" and "travel." Vacation, to me, conjures up images of Spring Break in Ft. Lauderdale; a cruise through the Virgin Islands; a rented lake house in Michigan; Disney with family; or an annual pilgrimage to a favorite resort in Aspen. The purpose of a vacation is to have fun, relax, unwind, and perhaps engage in favorite hobbies I don't have enough time for in everyday life.
These shoes from Poetic License are among my favorites.
"Travel" may also involve all of those things (and I generally hope it does), but travel is much more than a good book and a pina colada in paradise. Arthur Frommer (of guidebook fame) summed it up perfectly when he said "[a]t its best, travel should challenge our preconceptions and most cherished views, cause us to rethink our assumptions, shake us a bit, make us broader minded and more understanding." Travel is an opportunity to learn; to experience life from a different point of view; and if we're lucky, to connect with other cultures and other people in a way that has a meaningful impact on both sides. Backpacking on my own through Europe; spending three months volunteering with a governmental entity in Australia; hiking for days through unmarked (and bear heavy) territory in the mountains of Wyoming; studying language and history in Spain; and exploring small Irish towns on foot and by car - a treasured travelogue that has broadened my horizons in ways that a day at Epcot and a week on the beach never will.
Of course, vacation has its own intrinsic value, and I think it's important to make room for both. Tonight I booked a true vacation, and I'm looking forward to four days of fun and frivolity with friends when the time comes. But, I'm also dreaming of travel, and all the wonder that new and exotic places bring. This midi skirt from Chicwish paints a picture of Santorini that has me longing to explore the ancient cities of Greece, a place that has intrigued me since I fell in love with the Iliad and the Odyssey in high school English. And, if the picturesque seaside scene is any indication, I'm guessing Greece will offer plenty of "vacation" opportunities, too. Sign me up!
Safety Pin Clutch (Bodhi); "Van Gogh" bangle bracelet (Erwin Pearl); Citrine ring (David Yurman). Thanks to photographer Faith Blackwell for capturing a candid moment over drinks in the bottom right photo.


I am looking at a 2002 F150 Lariat. It has under 300,000 miles . Is there anything you can tell me about this type of truck??
A Timesert and good as new! Make sure you torque them to 28 ft/lb and you won't have any more blowouts.
Give it a good inspection. Look underneath for rust, leaks, damage, etc. Check the ball joints, tie rod ends, pitman arm, idler arm, and sway bar links for looseness.
The 2 valve 5.4 is a solid engine. That's the engine that was in that guy's million mile van.


Understanding the impacts of consumers on the abundance, growth rate, recovery and persistence of their resources across their distributional range can shed light on the role of trophic interactions in determining species range shifts. Here, we examined if consumptive effects of the intertidal grazer Scurria viridula positively influences the abundance and recovery from disturbances of the alga Mazzaella laminarioides at the edge of its geographic distributions in northern-central Chilean rocky shores. Through field experiments conducted at a site in the region where M. laminarioides overlaps with the polar range edge of S. viridula, we estimated the effects of grazing on different life stages of M. laminarioides. We also used long-term abundance surveys conducted across ~700 km of the shore to evaluate co-occurrence patterns of the study species across their range overlap. We found that S. viridula had positive net effects on M. laminarioides by increasing its cover and re-growth from perennial basal crusts. Probability of occurrence of M. laminarioides increased significantly with increasing density of S. viridula across the range overlap. The negative effect of S. viridula on the percentage cover of opportunistic green algae—shown to compete for space with corticated algae—suggests that competitive release may be part of the mechanism driving the positive effect of the limpet on the abundance and recovery from disturbance of M. laminarioides. We suggest that grazer populations contribute to enhance the abundance of M. laminarioides, facilitating its recolonization and persistence at its distributional range edge. Our study highlights that indirect facilitation can determine the recovery and persistence of a resource at the limit of its distribution, and may well contribute to the ecological mechanisms governing species distributions and range shifts.
Data Availability: Data are available from http://www.ceazamet.cl/index.php?p_cod=changolab and from Figshare (10.6084/m9.figshare.1514989). All other relevant data are within the paper and its Supporting Information files.
Funding: Research was supported by grants from the Fondo Nacional de Desarrollo Científico y Tecnológico of Chile (FONDECYT) to MAA (grant #11121360), BRB (grant #1090488 and 1120988) and NV (grant #3100014 and 1141037), and by the Programa de Mejoramiento de la Calidad y la Equidad de la Educación Superior (MECESUP) to NV (grant #AUS0805).
Much emphasis has been placed on the importance of biotic interactions and their potential to influence the distribution of species at different spatial and temporal scales [1–5]. Together with environmental constraints, competition, predation, facilitation, and mutualism can determine species' distributional limits [4–6]. Few studies, however, examine the influence of consumer effects on resource recovery and persistence at both consumer and resource range limit, which can be relevant for species geographic distributions. Theoretical studies suggest that trophic interactions could significantly account for species geographic co-occurrences and range shifts [2,7]. Since range edge populations are characterized by low effective population size and generally low dispersal potential , they appear especially prone to local extinction triggered by both abiotic and biotic factors [3,9]. In this way, edge populations of resources could potentially expand or contract depending on variation of environmental barriers to dispersal and the intensity and type of consumption experienced at different life stages; i.e. the magnitude and direction of trophic interactions. This idea is in part related to predictions of the 'stress-gradient hypothesis' (SGH) , which suggest that the frequency of competitive and facilitative interaction between species pairs vary inversely across gradients of physical stress or ecosystem productivity . Thus, the rate of predation and facilitative interactions at the geographic range of a species is a matter of great interest to understand changes in species distribution in face of global change .
Herbivore-plant interactions are one of the most important consumer-resource interactions in terrestrial and aquatic ecosystems, with herbivores having both negative and positive effects on plants from local to biogeographic scales [13–17]. In marine communities, molluscan herbivores can dramatically reduce algal biomass and alter algal distribution patterns and spatial structure [15,16,18–22]. Grazing on competitively superior species or epiphytes can indirectly facilitate recruitment and growth of subordinate macroalgal species at small spatial scales [23,24]. Some marine herbivores can also directly influence vegetative tissue growth through stimulating overcompensation , by spore dispersion , and addition of nitrogen from excreta [27,28]. Thus, the direction of grazing effects commonly depends on algal life history traits and grazer feeding behavior [29–31]. For example, grazers can have stronger negative effects on ephemeral than calcareous algae, as the latter are resistant to consumption  and can benefit from moderate grazing. The magnitude of effects, however, depends on grazer body size and density , which usually vary across the geographic range of a species . Given the stressful conditions experienced by algae at their range edge, herbivores could facilitate their persistence  and increase the potential of range expansion. Whilst the negative and positive impacts of herbivores on the fitness of their resources have been well documented, their consequences for algal range distribution have been poorly examined (see ). This information can be useful to predict the influence of trophic interactions on potential range shifts of resources, given changes in the demography and per capita effects of key consumers across either geographic or physical gradients [33,34].
Overall, at the range edge of grazer and/or algal species, recovery from disturbances and persistence is expected to be sensitive to environmental drivers and variations in grazer–alga interaction strength. On the one hand, it is likely that, at their geographic range limit, herbivores could have moderate or null effects on algal abundance, because suboptimal environmental conditions could negatively affect grazers' population densities, foraging activity, or both [8,35]. On the other hand, given low densities of algae at their range limit—due for example to low connectivity with source population or because individuals are beyond their physiological tolerance threshold —edge populations can be especially prone to local extinction . In these cases, species-specific grazing on dominant competitors can facilitate the recovery and consequently the persistence of the subordinate algae [23,38].
Along the coast of northern-central Chile, a broad transitional zone is located around 30°S-41°S [39,40]. A 200 km wide section on the northern edge of this area, between 30°S-32°S, is the polar or equatorial edge of the geographic range of several intertidal species. This zone comprises the complete geographic range of the northern–clade of the corticated alga Mazzaella laminarioides , while the molluscan grazer Scurria viridula finds here its polar limit. Thus, the complete geographic range of the northern clade of this alga overlaps with the herbivore across a zone limited to around 200 km, potentially establishing an herbivore-alga interaction system. It has been observed that the northern clade of M. laminarioides has a strong population structure with signs of recent reduction of population size . In addition, a small population of this species has been observed in a site ca. 120 km northern of its actual range limit. This fragmented distribution and unstable population structure  can be caused by discontinuities in physical oceanographic conditions in sea surface temperature (SST) , and/or biotic conditions experienced at its range, which has not been previously examined. Previous experimental studies conducted south of the range overlap, where a southern clade of M. laminarioides is present , showed that most species of the intertidal molluscan grazer assemblage can have strong negative effects on early successional algal species [43,44]. In addition, some species of the generalist grazer assemblage can also have positive consumptive effects on the establishment of M. laminarioides during late succession [44,45]. However, this effect seems to be transient and concentrated on early life stages of the corticated alga species. It is unclear what are the implications of grazing on M. laminarioides local recovery, persistence and spatial distribution, which might modulate the potential range expansion or contraction of marginal populations of the northern clade of this alga. Because M. laminarioides has low dispersal potential, its spatial recovery, persistence and distribution might be influenced by S. viridula, which is the larger and dominant grazer in mid and high intertidal levels in northern Chile .
Using a mixture of intensive field observational surveys (thirteen-year dataset) and manipulative experiments, we examined the effect of the grazer S. viridula on the recovery, persistence, abundance, and spatial distribution of the northern clade of the late successional algal species M. laminarioides across the section of coastline where this species overlaps with the herbivore. It has been observed that opportunistic algal species (e.g. Ulva spp.) can persist in absence of herbivores outcompeting M. laminarioides [44,45]. Clumps of M. laminarioides, as other Mazzaella algae species, can recolonize via regrowth from perennial basal crusts and fronds trimmed by disturbances like strong waves, heat stress, and disintegration of fronds by spore release . Thus, we hypothesized that S. viridula could indirectly facilitate M. laminarioides growth and abundance by grazing their main algal competitors, or by stimulating direct compensation of vegetative tissue ("facilitation-hypothesis"). Thus, we predicted that across the range overlap the probability of occurrence of M. laminarioides depends positively of the density of S. viridula independently of major environmental gradients, such as the latitudinal variation in sea surface temperature (SST) (Fig 1A). Occurrence patterns of the algae could resemble the geographic distribution and small scale density pattern of the herbivore. Alternatively, given the homogeneous genetic population structure of the northern clade of M. laminarioides , settlement and abundance of this species could be curtailed by direct consumption of early developmental stages [44,48], negatively affecting its recovery from, mechanical, disturbances and producing small-scale spatial heterogeneity ("consumption-control hypothesis"). Thus, the abundance of the alga could be negatively correlated with grazer density patterns. We tested these hypotheses using a field experiment, simulating mechanical disturbances through clipping M. laminarioides fronds and removing the entire alga from the substrate in presence and absence of the focal herbivore. In addition, we assess the main drivers of M. laminarioides distribution, including the presence of S. viridula, and the influence of physical factors, using a species distribution model (SDM) fitted to the long-term abundance data.
Fig 1. Map of the northern-central coast of Chile showing (a) spatial variation in sea surface temperature (SST) for the 0.25, 0.5, and 0.75 quantiles of the SST distributions recorded at each site for the 2009–2011 period, (b) location of study sites, and (c) percentage of plots where each of the four focal species was recorded at each site. The arrow in panel (b) indicates where manipulative experiments were conducted (site 10, Punta de Talca) and the open diamond indicates the location of a site (Talcaruca) where we only recorded SST.
Note that the herbivore and the alga species coexist only at sites 9, 10, 11 and 12 which correspond to the complete range of the northern clade of M. laminarioides .
All invertebrate manipulation in the field and laboratory were conducted according to relevant national and international guidelines. No animals were sacrificed during the experimental study or during the geographic surveys. In addition, the study sites are not privately owner, so that no permits for access were needed. Field activities and experiments did not involve endangered or protected species.
The study region corresponds to the pole-ward endpoint of the range of S. viridula, and to the range of the northern clade of M. laminarioides (for simplicity, hereafter referred to as M. laminarioides) [39–41,49], conforming a 'range overlap' spanning about ~200 km (see Fig 1). Along this biogeographic region, M. laminarioides forms extensive stands and dominates the mid- and high intertidal zones. The opportunistic algae Ulva rigida, U. compressa, and Pyropia orbicularis are abundant in high to mid-intertidal levels, interspersed by patches of the crusts Hildenbrandia lecannellieri and Ralfsia sp. Chthamalid barnacles form extensive patches in mid- to high intertidal levels and the mussel beds characteristic of central-southern Chile are scarce . The herbivore assemblage of the mid-high intertidal shore is characterized by chitons, the keyhole limpet Fissurella crassa, and scurrinid limpets like Scurria zebrina, S. viridula, and S. ceciliana to a lesser extent.
The corticated alga M. laminarioides has low dispersal potential, is long-lived, and, as other Mazzaella species, its recruits may coalesce into dense clumps that persist as a basal crust during stressful periods [47,51]. After damage produced by disturbances like strong waves, heat stress, and disintegration of fronds by spore release, individual clumps of this alga recolonize via regrowth from perennial basal crusts and trimmed fronds . The northern clade of M. laminarioides shows signs of a recent bottleneck, following a reduction of effective population size .
Scurria viridula is among the largest generalist molluscan grazer of the assemblage [46,48] of the region north of the range overlap (mean ± Standard Error of the Mean of maximum body length: 2.62 ± 0.15 cm), reaching high densities and frequencies of occurrence at the northern limit of the range overlap (11.9 ± 1.34 ind. m-2, Fig 1B and 1C). According to their radular scraping capabilities it can be considered an efficient grazer, capable of removing macroalgal spores and small plantlets at very high rates . Large densities of this species north of the range overlap suggest that this grazer species might have large population-level consumptive effects on algal communities. Previous studies suggest that S. viridula has expanded its geographic distribution by around 100 km , but recent observations suggest this expansion is larger (M. A. Aguilera & B. R. Broitman unpublished results). There is no available information, however, concerning potential algal range shift. Similarly, the influence of subtle abiotic gradients (e.g. sea surface temperature, Figure A in S1 File) and biotic factors on the distributional limit of these species is still unclear.
In order to determine co-occurrence distributional patterns (i.e. presence/absence measures) of the focal species across and beyond the range overlap, we used long-term abundance datasets (i.e. 1998–2011) obtained from a monitoring scheme conducted at fifteen sites spanning ~700 km of coastline from 28°S to 33.5°S (Fig 1). At each site, the presence of M. laminarioides and the density of S. viridula was recorded using 20 50 × 50 cm quadrats (divided in 25 fields), haphazardly positioned along transects about 15 m in length on two platforms in mid intertidal levels. Detailed explanations of sampling methods and schedules are published elsewhere [39,53]. Although we aimed to test whether grazer occurrences determine the alga occurrence pattern, the causality of the relationship can well be opposite (i.e. the algal occurrence determines the grazer density). We recorded SST by means of temperature dataloggers (Hobo, Onset) moored at ~1-meter depth (i.e. below zero level) at each site to represent the nature of the environmental conditions in the range overlap. The temperature dataloggers were monitored every 3–4 months between 2009 and 2013.
To determine if grazer and algal species were randomly, aggregated, or uniformly distributed over rocky platforms, and to characterize their patterns of spatial association, we recorded S. viridula density and M. laminarioides cover at different sites across the geographic range overlap (Fig 1B). We counted all individuals of S. viridula and recorded the percentage cover of M. laminarioides using 36 to 50 30 × 30 cm contiguous quadrats positioned along two 10 to 15 m-transects parallel to the shoreline at each study site. The sampling unit size considered has been shown to be appropriate to detect significant spatial variation in abundance of Scurria limpets , as most of them forage about 12 cm around their home scars . Similarly, this quadrat size allows for a representative site-scale quantitative characterization of the intertidal community, including foliose algae like M. laminarioides. The sampling was conducted between October 2010 and July 2011 in the mid-intertidal zone at three sites located in the range overlap (i.e. Limarí, Punta de Talca, and Huentelauquén; sites 9, 10, and 11, respectively, in Fig 1B and 1C).
To determine the consumptive effects of S. viridula on M. laminarioides abundance, persistence, and distribution at small spatial scales, we conducted an enclosure/exclusion experiment in the mid-intertidal level in the locality of Punta de Talca (30.9°S, 71.6°W, Site 10 and arrow in Fig 1B), which is located at the northern edge of the range overlap. According to the scraping feeding mode of scurrinid limpets, we assumed that consumptive effects of S. viridula on M. laminarioides concentrate on spores, basal crusts, and small plants . In addition, we considered the consumptive effects of this grazer on short trimmed fronds of M. laminarioides, because the fronds of this alga partially disintegrate after releasing the carpospores and can be completely removed after consumption by browser herbivores (e.g. Fissurella crassa, [44,55]) or trimmed by fish (authors' personal observations, Escobar and Navarrete unpublished data). Hence, as grazing by S. viridula may affect the rate of frond recovery (from basal crusts) and growth rate, we evaluated the effect of S. viridula grazing on different life stages of M. laminarioides. We selected 15 25 × 25 cm areas (see Figure A in S1 File) and in the center of each we left two clumps (4–6 cm diameter) of adult M. laminarioides distant ~6 cm from each other. One clump was trimmed at the basal portion leaving small erect thalli (1.5 cm, green in Figure A in S1 File), which mimicked the height of senescent fronds after spore release. For the second clump, fronds were completely removed leaving only the basal crustose thalli from where fronds can re-grow (brown patches in Figure A in S1 File). The rock surface around clumps was scraped clean with drill-mounted brushes and manual chisels, removing all organisms including encrusting algal fragments. This last procedure was intended to mimic conditions during early community succession. It is worth noting that in intertidal habitats release of primary substrate is a frequent process generated by carnivores, grazers, and physical disturbance . Experiments started during the season of vegetative growth and spore production of M. laminarioides (early summer to autumn), and finished before spore release and frond senescence (mid-winter to early spring). Each experimental area was randomly assigned to one of the three following treatments (n = 5): (a) Enclosure of two S. viridula (3.4 ± 0.16 cm shell length), according to local natural densities of this species in the range overlap , (b) exclusion of benthic grazers, where all herbivores were removed from the plots, and (c) control"open access" areas where all herbivores were allowed to enter and graze. Each plot allocated to treatment (a) or (b) was fenced with a 6 cm-high wire mesh deployed around the experimental area (see Figure A in S1 File, for exclusion/enclosure effectiveness), while those allocated to treatment (c) were marked with stainless-steel bolts (see Figure A in S1 File).
Manipulative field experiments similar to our study have used partial fences to control the potential artefact of fences on algal growth or grazer consumption. We conducted a pilot study to test the applicability/usefulness of this treatment in our study system (Figure A in S1 File). Our pilot study suggested that partial fences can affect experimental M. laminarioides clumps, because these procedural control were quickly removed by strong waves that are common in our study site (Figure A in S1 File). Thus, we did not include this treatment in our design because of its potential to alter algal growth and establishment. Although we did not include a 'fence effect' in our treatment design, a recent, temporally more intensive study conducted at the same site, and with comparable treatment design, suggested that fences can have minimal, and non-significant, confounding effects on algal recruitment and abundance (Figure A in S1 File). In addition, previous studies conducted in this system suggest that small height of the fences considered in the experiment (6 cm) do not enhance or impede algae recruitment and/or grazing rate compared with partial fences or open areas [44,56]. Additionally, we stringed atop of each fence a thin transparent nylon fishing line (0.1mm) to reduce the potential impact of fish grazing. Only two nylon lines were stringed across sides to create a grid that was wide enough (about 225 cm2) to avoid shading inside the experimental area. Previous studies have found no effect or artefact of this procedure (e.g. neither on algae growth nor recruitment), which is intended to reduce fish grazing inside experimental areas in fenced plots (enclosures and exclusion treatments) when compared with completely open areas .
In order to estimate grazing intensity in experimental "open access areas" and to follow algal settlement, we measured every two months the density of herbivores and both adult and juvenile M. laminarioides in the experimental platforms (Fig 2A). The percentage cover of bare space in enclosure and control was considered as a direct measure of foraging rate of the focal grazer species in each experimental set compared with exclusions (grazer-free areas). Thus, this measure can be considered as a net effect of the focal grazer integrating positive indirect effect on M. laminarioides through foraging on competitors. Monthly from December 2009 to May 2010, we monitored the percentage cover of all macrobenthic (> 3 cm) sessile organisms occurring in each experimental area by means of 25 × 25 cm quadrats (81 uniformly spaced intersection points). At each sampling date, the whole benthic community in each plot was photographed with a high-resolution digital camera and percentage cover estimations were conducted in the laboratory. Monthly, we also measured the length of all M. laminarioides fronds re-grown from trimmed clumps. The area of each basal crust, and the number of fronds regrowth from them were measured at the end of the experiments.
Fig 2. Predicted probability (± 95% CI) of occurrence of the corticated algae Mazzaella laminarioides determined by density of the grazer Scurria viridula found at four sites located within the range overlap estimated through logistic regressions.
Using information from the long-term monitoring program across different sites, we conducted multiple logistic regression analyses, with site latitude, maximal local (0.75 quantile) SST, and densities of S. viridula as explanatory variables, and presence/absence of M. laminarioides as dependent variable. Maximum likelihood was used to estimate model parameters. Before the analyses, we computed for each explanatory variable its variance inflation factor (VIF) in order to detect collinearity. The term with highest VIF was sequentially removed until all remaining terms showed VIF < 3 . Akaike and Bayesian information criteria (AIC and BIC respectively) were used to find the best fit to the probability of occurrence of M. laminarioides. We compared all possible regression models using the meifly package in the R environment version 3.0 (R Development Core Team 2013). The model with the lowest AIC and BIC values was selected as the best fit (see Table A in S1 File).
The small-scale spatial structure (cm to meters) of S. viridula and M. laminarioides abundance data was analyzed using spatial correlograms with Moran's I . We determined the statistical significance (α = 0.05) by bootstrapping our observations . The significance at each lag was estimated with the distribution of autocorrelation coefficients obtained by randomly re-sampling the data set and recalculating the coefficients 1000 times. A global autocorrelation test was conducted by checking whether each lag contained a least one significant correlation after probabilities were adjusted using a Bonferroni correction for multiple tests (α' = 0.05/number of distance classes). Interspecific spatial association of the focal grazer and algal abundance at small-scales (cm to meters) were estimated through Pearson's correlations (r) between the grazer density and alga percent cover. Significance was calculated through a t-test in which the degrees of freedom were corrected according to the degree of autocorrelation (Moran's I) between data sets (quadrats at the same distance classes) in the contiguous quadrat sampling data . Correlations at each study site were calculated on averaged abundance data.
For the manipulative experiment, changes in percentage cover of ulvoids and bare rock, in addition to canopy cover and growth rates of trimmed M. laminarioides clumps were analyzed using one-way repeated measures analysis of variance (RM-ANOVA), using time as the repeated factor. Trimmed fronds and crusts of M. laminarioides clumps were analyzed separately. The former started to grow three months before the end of the experiment, thus we considered only this time interval for analyses of algal growth and canopy cover. All data were log-transformed to improve variance homogeneity. The Hyund-Feldt correction was used to adjust degrees of freedom when data did not meet sphericity assumptions for univariate tests . In the case of significant effects among treatment differences (between subjects), we used the following planned contrasts: (1) to evaluate effects of all herbivores (total herbivory) we compared the control versus exclusion, (2) to evaluate the effects of enclosed S. viridula versus those of other herbivores, we compared enclosures versus control and (3) to evaluate the effect of S. viridula in absence of other herbivores we compared enclosure versus exclusions. Dunn-Šidák correction was used to adjust significance levels for the multiple contrasts performed. As we did not include a procedural control in our experiment (see arguments above and in Figure A in S1 File), comparisons between fenced areas and open plots (controls), which test for the effect of all herbivores of the system, should be considered with caution.
Differences in re-grown frond density among treatments were tested with a one-way ANOVA using the temporal average frond density of each M. laminarioides crust in each plot. Data were log-transformed in order to meet the assumption of homogeneity of variance, which was graphically explored by means of residuals-vs.-fits plots. In the case of significant effects, we used planned contrasts as described above.
In order to determine the direction and magnitude of grazing effects on algae and to provide comparable information we estimated per capita interaction strength in field experiments. Within plots, colonization of ephemeral algae started a few days after rock clearance and reached an established stage after 18–20 weeks, about the colonization phase of early successional algal species in the region. Hence, we estimated the consumptive effect of natural densities of S. viridula on dominant ephemeral algae and on bare rock cover, considering their average cover pooled for the first twenty weeks of the study. We also estimated grazer effects on M. laminarioides frond cover.
To quantify the interaction strength (per capita effects) considering natural densities of S. viridula we used the "Dynamic Index" (DI) suggested for resources with positive exponential growth, such as early-succession species and ephemeral algae (e.g.[35,61]). The index was calculated as: DI = (ln (CovEN/CovEX))/N×t, where CovEN is the mean specific algal or bare rock cover in the S. viridula enclosures, CovEX is the mean algal cover in the grazer exclusions, N is the density of S. viridula in the experimental plots and t is the elapsed time of experiments, in this case in weeks. We also computed DI × natural density of S. viridula observed within and north of the range overlap in order to estimate population effects  of this grazer. It is worth noting that although this measure can provide useful information about potential grazer population-level effects, it assumes linear per capita effects across a range of densities of the grazer (see [62,63]). Thus, results of these analyses must be interpreted with caution . An average population effect ≤ 1 (100% of plants removed by herbivores) indicates either total prevention of algal recruitment or production of 1 m2 of bare rock per week. This allowed us to evaluate potential impact of the S. viridula on M. laminarioides, when natural densities in the range overlap zone resemble those found north of its range edge. Confidence intervals (95%) for effect estimates were obtained through a bootstrapping procedure .
Coastal ocean temperature across the region showed a persistent and localized decrease in SST from ~14.5°C at 28°S to 12.8°C at 30.5°S (Fig 1A) over the period of 13 years (i.e. 1998–2011) which is consistent with the distributional pattern and northern range edge of M. laminarioides. We also observed a drop in SST at a single study site located ~29° S (Los Burros), where an isolated local population of M. laminarioides is located over 120 km equatorward of the previously reported edge of the range (Fig 1A).
Quadrat surveys showed that both S. viridula and M. laminarioides had higher incidences (i.e. number of times a species was found at a site over the period considered) across the range overlap when compared with sites north (see Fig 1C). For the case of M. laminarioides, Akaike and Bayesian information criteria (AIC and BIC, respectively) were smaller for the model that included S. viridula density, latitude, and maximal SST as explanatory variables (Table 1). According to the selected model, the density of S. viridula contributed significantly to the prediction of M. laminarioides probability of occurrence (Table A in S1 File). The odds ratio for S. viridula was estimated as 1.12 with 95% CI ranging from 1.05 to 1.20 (Fig 2, and Table A in S1 File), indicating that for one unit of increase in S. viridula density, a quadrat had ca. 1.12 chance of having M. laminarioides compared to not having the alga, an increase in the odds of having M. laminarioides of ca. 10%. Maximal SST was also an important contribution to M. laminarioides occurrence across the range considered (Table 1, and Table A in S1 File).
Table 1. Model selection according to Maximum Likelihood (logL) parameter estimation, Akaike and Bayesian Information Criteria (AIC and BIC, respectively) for the occurrence of the corticated alga M. laminarioides.
The model with the lowest information criteria is in bold. Latitude (Lat), maximal SST (SSTmax), and density of the grazer S. viridula (Scu) were included in the full model as explanatory variables. Minimal and median SST were excluded from the full model due to high variance inflation ratios. Coefficient for the intercept is presented before each other terms of the model.
Small-scale spatial surveys (cm to meters) showed that S. viridula density remained relatively constant through time and along the shoreline at the experimental study site (Fig 3A). Densities of this grazer were similar across the range overlap, with average densities (± SEM) of 2.36 ± 0.68, 3.05 ± 0.58, and 2.17 ± 0.74 ind. 900cm-2 at Limarí, Punta Talca, and Huentelauquén, respectively. Average canopy cover of M. laminarioides was around 20% at the start of the study (summer) in mid-intertidal levels in the study site, stabilizing around 100 days from the beginning of the study at ~70% (Fig 3B). Average percentage cover measured between late summer and early autumn across the range overlap was 32.12 ± 6.06, 55.7± 10.67, and 32.82 ± 6.09% 900 cm-2 in Limarí, Punta Talca, and Huentelauquén, respectively. The analysis of intra-specific spatial structure at small scales (cm to meters) showed that the grazer species was randomly distributed at all sites (see Table B in S1 File). Similarly, the spatial distribution of M. laminarioides was random at Limarí, but showed a more aggregated pattern at Punta Talca and Huentelauquén according to significant autocorrelation estimates at the lower distance classes (i.e. lag 0, about 30–90 cm, see Table B in S1 File). According to our broad-scale analysis of species occurrences, abundances of S. viridula and M. laminarioides were positive and significantly correlated at the scale of quadrats (30 × 30 cm) in two sites within the range overlap (Limarí and Huentelauquén, Table 2).
Fig 3. Average abundance (±SE) of (a) the grazer Scurria viridula and (b) the corticated alga Mazzaella laminarioides recorded in the experimental platforms at Punta Talca, located at the core of the range overlap of the two species.
Table 2. Summary of Pearson spatial correlation (r) between densities of S. viridula and cover (%) of M. laminarioides at three sites located in the range overlap.
Modified t-tests were performed to determine significant differences in the herbivore-alga spatial correlation. Degrees of freedom and P-values were adjusted by presence of spatial autocorrelation in the data set (Dutilleul`s correction).
Grazing by S. viridula in enclosure plots significantly increased bare rock cover by reducing the abundance of fast-growing ulvoid algae (Ulva rigida and Ulva compressa) throughout the study when compared with exclusion plots (Fig 4A and 4B, and see Table C in S1 File). Effects on bare rock and ulvoid algae cover were variable through time (i.e. significant Time*Treatment effects; Table C in S1 File). Grazing effects of enclosed S. viridula on bare rock and ulvoids were not statistically different from those observed in control free-access plots (see planned contrast in Table C in S1 File). These results suggest that grazing effects on bare rock and ulvoids in free-access plots were mostly due to S. viridula grazing. Trimmed clumps of M. laminarioides inside experimental areas started growing after 100 days from the beginning of the experiment (see Fig 4C). In presence of S. viridula, percentage canopy cover of trimmed plants of M. laminarioides was significantly higher than in exclusion areas (see Fig 4C, and Table C in S1 File), suggesting that the presence of the grazer benefited the regrowth of the trimmed fronds. We observed a slightly, albeit not significantly, higher canopy cover in control areas compared with exclusion areas (Fig 4C, see planned contrasts in Table C in S1 File).
Fig 4. Main ecological changes recorded inside experimental plots in the field experiments, corresponding to enclosure of the grazers Scurria viridula, exclusion of all grazers and 'open areas' (control).
Average percentage cover (± SE) of (a) bare substrate, (b) green opportunistic ulvoid algae and (c) the corticated alga Mazzaella laminarioides.
Average length of trimmed fronds of M. laminarioides clumps was not significantly different among treatments after ~200 days from the onset of the experiment (see Fig 5A and Table D in S1 File). After 5 months of study, small fronds of ~2 cm in length of M. laminarioides grew from basal crusts generated at the start of the experiments. At the end of the study, the density of small fronds growing from these crusts was significantly higher in S. viridula enclosures than in exclusion and control plots (Table 3, Fig 5B). In contrast, frond density was not significantly different between grazer exclusion and control plots (planned contrasts: Table 3).
Fig 5. Performance of the corticated alga Mazzaella laminarioides in the presence and complete absence of Scurria viridula inside experimental plots.
(a) Mean (± SEM) fronds length (cm) of plants trimmed at the start of the experiment and (b) average number of fronds (± SEM) regrown from basal non-calcareous crusts created inside experimental plots.
Table 3. One-way ANOVA on density of frond re-growth from basal crust of the alga M. laminarioides presents inside the experimental treatments.
P-values were adjusted using Dunn-Sidák correction for multiple test.
S. viridula had clear per capita effects on both bare rock availability and ulvoid cover of the early successional community (Fig 6). Significant negative average per capita effects on ulvoids were mirrored by positive, albeit moderate, effects on bare rock availability (see Fig 6A). Enhanced growth of trimmed fronds of M. laminarioides inside S. viridula enclosures took place during the final experimental stage (see Fig 4A). In general, we found that S. viridula had positive effects on canopy cover of trimmed plants of M. laminarioides (Fig 6A). Estimation of population effects of S. viridula considered natural densities of this species recorded at the study site and northern the range overlap. Expected average population effects of S. viridula showed that this grazer was able to remove around 60% of ulvoids (spores and plantlets) per m2 per week (Fig 6B). According to the positive per capita effects observed in our field experiments, natural populations of S. viridula enhanced M. laminarioides canopy cover by about 44% per m2 per week in the range overlap zone (Fig 6B). In the locality of Los Burros, distant about 120 km northern its range edge, a population of M. laminarioides still persists (cover = 34.1 ± 7.18%, Fig 1C) and population effect of S. viridula were estimated to enhance in canopy cover in 15.8%. In sites about 200 km northern the 'range overlap' (i.e. Carrizal Bajo) where densities of S. viridula are high but M. laminarioides is yet absent, it is expected that S. viridula might enhance M. laminarioides canopy cover by about 38%. Meanwhile considering the densities recorded for this grazer southern the range overlap (i.e. about 250 km, in Las Cruces), it is expected that this species might contribute to enhance M. laminarioides cover and frond regrowth by about 5% per m2 per week.
Fig 6. Strength and direction of the interaction between the grazer S. viridula and the alga M. laminarioides, measured as the grazer capacity to influence the recruitment of algae and bare rock production during early succession, and the recovery M. laminarioides fronds (i.e. Average per capita (a) and population effects (b)).
Bars are 95% confidence intervals estimated through a bootstrapping procedure.
At its range limit, the grazer S. viridula showed strong effects on populations of M. laminarioides by facilitating frond re-growth after mechanical disturbance. In line with our hypothesis of positive effects, S. viridula negatively affected the percentage cover of opportunistic green algae, which are suggested to affect the growth of corticated algae. Accordingly, we found a positive spatial correlation, at different scales, between the herbivore and algal species throughout the range where both overlap in their distribution.
We found a consumer-resource dynamic that was likely established through both indirect and direct effects in the species range overlap [64,65]. On the one hand, the negative grazing effects on opportunistic green algae could have resulted in an indirect positive effect on M. laminarioides through competitive release. Rapid nutrient uptake and high growth rates confer opportunistic algae the ability to outcompete perennial, slow-growing macroalgae in the absence of external disturbances . Competition for light and nutrients between opportunistic and perennial algae is intense, but most grazers prefer to feed on early life stages of opportunistic algae [38,66]. It has been also shown that removal of opportunistic algae can facilitate the recovery of algal canopies with more complex morphological forms especially in systems where disturbances are more intense . Thus, as suggested by the 'stress-gradient hypothesis', some combinations of life history traits and stress factors can switch ecological interactions from negative (e.g. consumptive control) to positive in plant-herbivore interactions . These evidence suggests the hypothesis that, through selective grazing on spores and recruits of competitively dominant opportunistic ulvoids (mainly U. rigida and U. compressa), S. viridula could indirectly benefit the recovery and abundance of M. laminarioides. On the other hand, corticated algae with a crustose phase or with a persistent basal crust formed by tightly arranged cells, like M. laminarioides, may tolerate and benefit from intense grazing through compensatory growth or uptake of nutrients from herbivore's excretions [27,38]. Such direct positive effects of grazers on algal persistence have been shown in other marine systems (e.g. coral reefs, ). For example, stimulation of meristematic tissue by grazing, the chiton Choneplax lata increases growth of the coralline algae Porolithon pachydermus . Since perennating basal crusts or holdfast are key structures of recolonization of different Mazzaella species , we could propose a second, competing hypothesis predicting that moderate grazing by S. viridula on these structures could contribute to M. laminarioides recovery through stimulating the re-growth of fronds. In agreement with this hypothesis, we found that at the end of our experiment the cover of M. laminarioides frond (of the single trimmed clump) was about 30% in S. viridula enclosures compared with 18% in control (open areas). In natural stands of M. laminarioides sampled with the quadrat-sampling protocol in the same study site, we observed that M. laminarioides covered 71.8% of the substratum in autumn. On the same sampling date, we observed that approximately two or three entire clumps (8cm across) of M. laminarioides were present within each sampling quadrat (900 cm2), with each clump accounting about 25% to 36% to the total M. laminarioides cover. This suggests that the 'recovery potential' of M. laminarioides, measured as the capacity of frond re-growth from trimmed clumps, was indeed enhanced by S. viridula grazing. It should be noted that as we did not include an 'intact' M. laminarioides'clump treatment in our experiments, algal recovery to a reference natural state in presence of the herbivore needs to be considered with caution. Therefore, further manipulative work is needed to disentangle the processes (e.g. competitive release and compensatory growth) generating positive algal responses in correlation to grazing. Climate change factors, such as eutrophication and ocean acidification, have been shown to benefit the proliferation of ephemeral and foliose algae; according to recent experimental work conducted elsewhere  and our results, grazing activity can exert a firm control on ephemeral algae and thus act as a compensatory mechanism that might counteract the impacts of disturbances on natural communities.
Significant positive spatial associations between grazer density and M. laminarioides cover was detected in two sites, corresponding with the patch structure of the alga. Grazer distribution, however, was random at all study sites precluding any inference about potential causal relationships between grazer and algal distribution at small scales. Spatial structure could be related to processes like patchy recruitment patterns and/or post-settlement mortality. Meanwhile, a lack of spatial structure in species distribution is commonly attributed to either the effects of random spatial processes, or that samples were collected over unappropriated spatial scales . In this context, intertidal grazer distributions can change from gregarious when resting to either random or uniform while foraging . Likely, our sampling protocol only included the foraging phase of the grazer which could have a more gregarious spatial patterns during the resting period. Nonetheless, previous studies suggest that the spatial scale considered in our study is appropriate to determine abundance of the study species [46,54]. In addition, competitive interaction (interference) with other grazers could also affect the distribution pattern of S. viridula (e.g.), but no studies have been conducted to test these hypothesis.
In central Chile, previous field and laboratory experiments have identified grazers, such as Chiton granosus and Scurria araucana, as able to enhance recruitment and abundance of M. laminarioides [44,45]. These species show similar grazing strategies as S. viridula, removing spores and plantlets by a "scraping-grazing" foraging mode. Together, these species could have an additive, or even redundant, contribution to the maintenance of M. laminarioides across the range of this alga. In central Chile, coastal localities where nutrient supply is locally higher show increased negative effects of the grazer assemblage on ephemeral algae, and increased growth rates of corticated alga like M. laminarioides . Our study site, Punta Talca, is located near a persistent upwelling center . As expected from the local drop in SST observed at this location, growth and recovery potential of M. laminarioides is expected to be high due to high nutrient concentrations associated with coastal upwelling activity . According to the low fronds re-growth rates and high bare rock cover observed in control areas of our field experiments, we suggest that other functionally different and abundant herbivores like the keyhole limpet Fissurella crassa, the pulmonate Siphonaria lessoni and fish have a strong negative effect on abundance and recovery of M. laminarioides through browsing on its fronds (e.g. ). Therefore, the functionally diverse local herbivore assemblage can impact different life stages of the corticated algae through differential grazing modes thus producing contrasting effects on algae distribution. Hence, both competitive interaction of M. laminarioides with opportunistic fast-growing algae like ulvoids and browsing by other grazers, such as large keyhole limpets, could prevent re-regrowth and control abundance of this alga in natural conditions. The lack of procedural controls in our experiment may hinder clear-cut interpretations of the differences between open (all herbivores effects) and fenced areas (exclusion, S. viridula enclosure). Nonetheless, a recent study conducted in this system showed no confounding effect of fences neither on algal recruitment nor abundances (see Figure A in S1 File, and see also  for low shore habitat). Thus, we interpret that the differences in M. laminarioides growth and abundance observed in our experiments were driven by the presence/absence of the focal herbivore species and not through experimental artefacts of the exclusion/enclosure method utilized. It is worth noting that appropriate procedural controls are necessary in field exclusion experiments, and these treatments should be included in experimental studies, either as a previous pilot study and/or directly in the final design.
Theoretical studies have shown the importance of considering biotic interactions as part of species distribution models (e.g. [2,6,71]). Biotic interactions can interact with abiotic factors like desiccation or wave stress to determine intertidal species distributions . The significant contribution of maximal SST to our species distribution model (SDM) reinforces the role of abiotic factors on biogeographic patterns of intertidal species [36,72]. For example, changes in nearshore oceanographic conditions can influence the connectivity and dispersion of intertidal organisms (e.g.[37,50,73]). Similarly, SST can be negatively correlated with nutrient supply in coastal habitats, which in turn influences the herbivore-alga dynamic [43,74]. Our SDM showed that including the grazer S. viridula in the logistic model improved the estimation of M. laminarioides occurrence probability over SST alone. Notwithstanding, we recognize the limitations of our sampling methods and the difficulty to infer causality from the significant relationship between grazer density and M. laminarioides occurrence. Recent evidence suggests that S. viridula has expanded its range about 200 km south of its historical range edge, despite no evident changes in environmental drivers like SST having been detected (but see ). However, no information is available about potential changes in the distribution of M. laminarioides (expansion or contraction of its range) regarding changes in environmental trends (, and see below).Considering the low local densities of this grazer found in the newly colonized range (e.g. Las Cruces), the expected population effects on the southern clade of M. laminarioides is still low compared with its effects estimated for the northern clade in the study site (an increase of about 5.2% of algal cover versus 38% estimated in the study site). Thus, the potential for M. laminarioides to expand its range edge northward might be mediated by limited dispersal [73,76], the ability of spores to grow up under higher heat stress [34,77], and also by facilitative grazing effect on the re-growth and persistence of this alga (this study). Thus, net grazing effects on re-growth from disturbances and persistence of algae may have an influence on algal range shifts when physical conditions open a window of opportunities for colonization in new geographic ranges. Transplants of M. laminarioides beyond its range edge are biologically risky because of accidental dispersal of propagules, so we did not perform experiments north of the range overlap zone. We found M. laminarioides (fronds cover = 34.1% ± 7.18) in Los Burros, located about 120 km northern its established range edge. This isolated population could be a relic after past northern expansion of M. laminarioides by relaxation in barriers to dispersal (i.e. upwelling fronts). Demographic and phylogeographic studies provide cursory support for this interpretations showing that edge populations have reduced genetic diversity and are highly structured . Nonetheless, as we observed in our study, persistence of the isolated population of M. laminarioides at Los Burros is strongly associated to low SST, and to a lesser extent by indirect facilitation of S. viridula. In this context, our results suggest that S. viridula enhances the recovery of M. laminarioides following disturbances by about 16%. We also estimated that about 230 km north of its current equatorial range edge, where M. laminarioides is not present (i.e. Carrizal Bajo), densities of S. viridula are equivalent to those presents at Punta Talca. Thus, densities of this grazer are expected to be high enough to influence the recovery of M. laminarioides to the north of its range edge. Since no effects were observed on the establishment of this alga (i.e. spore settlement-germination), physical factors (e.g. limiting spore dispersion and heat stress [34,73]) seem to be critical for its establishment at this site. In this way, changes in physical factors like sea and air temperature wind and/or acidification, at the magnitudes predicted by global change models , could constrain the distributional range of M. laminarioides while an increase in nutrients concentration by upwelling intensification and grazer indirect facilitation (, and this study) could compensate this effect at its range edge . Hence, an interplay between negative control of spore dispersion/settlement by physical stress and positive influences of grazing on recovery and persistence seem thus to be important for maintaining M. laminarioides geographic distribution.
In conclusion, trophic interactions can have a key role as post-settlement processes, operating at small spatial scales and probably influencing species recovery from disturbances and population persistence at broader scales. Grazing effects by S. viridula on different life stages of M. laminarioides improve their ability to recover from disturbances likely via enhancement of recolonization from perennial basal crusts, ameliorating interspecific competition, or a combination of both processes. Other herbivores, however, have negative effects on the re-growth of fronds of M. laminarioides and can thus control its abundance and distribution in natural conditions. Our findings suggest that while physical barriers to dispersal are relevant to determining species range distribution and establishment via limitation of spore dispersion , variation in the intensity and magnitude of biotic interactions can influence the ability of species to persist or collapse at the edge of their geographic range. Such local processes, in turn, can be critical for species to further expand or contract their range after physical barriers are relaxed by environmental variation.
S1 File. Details of the field experimental procedures conducted for the herbivore-alga pair, and tables with statistical results.
Preliminary experiments and enclosure/exclusion treatment design of field experiments utilized to test the effect of Scurria viridula on the ability of algae to colonize and regrowth from trimmed clumps and basal crusts (Figure A). Maximum likelihood estimates of model parameters and model selection for Scurria-Mazzaella interaction and Sea surface temperature (SST) (Table A). Summary of spatial autocorrelation analysis at small (cm to meters) spatial scales for the herbivore and the algae species (Table B). Summary results from repeated measures ANOVA of a) bare rock and b) ulvoids (i.e. Ulva compressa, U. rigida) found in cleared areas of the experimental plots in the Scurria-Mazzaella field experiment (Table C). Repeated measures ANOVA of a) percent canopy cover and b) frond length of trimmed clumps of Mazzaella laminarioides (Table D).
Comments of results and fruitful discussion with all members of Chango-Lab are greatly appreciated. Two anonymous reviewers greatly helped to sharpen our thoughts. Sergio A. Navarrete kindly provided SST information for sites 13, 14 & 15 in Fig 1A and access to the database of long-term, large-scale ecological observations. John Griffin and four anonymous reviewers greatly improved a final version of this manuscript.
Conceived and designed the experiments: MAA. Performed the experiments: MAA. Analyzed the data: MAA NV. Contributed reagents/materials/analysis tools: MAA NV BB. Wrote the paper: MAA NV BB.
1. Araújo MB, Luoto M. The importance of biotic interactions for modelling species distributions under climate change. Global Ecology and Biogeography. 2007;16: 743–753.
2. Araújo MB, Rozenfeld A. The geographic scaling of biotic interactions. Ecography. 2014; no–no.
3. Lavergne S, Mouquet N, Thuiller W, Ronce O. Biodiversity and Climate Change: Integrating Evolutionary and Ecological Responses of Species and Communities. Annual Review of Ecology, Evolution, and Systematics. 2010;41: 321–350.
4. Coulson LA, Perrin C, Roberts DG, Minchinton TE, Ayre DJ. Can limited dispersal or biotic interaction explain the declining abundance of the whelk, Morula marginalba, at the edge of its range? Biological Journal of the Linnean Society. 2011;103: 849–862.
8. Sagarin RD, Gaines SD, Gaylord B. Moving beyond assumptions to understand abundance distributions across the ranges of species. Trends in ecology & evolution. 2006;21: 524–30.
10. Maestre FT, Callaway RM, Valladares F, Lortie CJ. Refining the stress-gradient hypothesis for competition and facilitation in plant communities. Journal of Ecology. 2009;97: 199–205.
11. Bertness MD, Callaway RM. Positive interactions in communities. Trends in Ecology & Evolution. 1994;9: 191–193.
13. Schmitz OJ. Herbivory from Individuals to Ecosystems. Annual Review of Ecology, Evolution, and Systematics. 2008;39: 133–152.
17. Gaines SD, Lubchenco J. A Unified Approach to Marine Plant-Herbivore Interactions. II. Biogeography. Annual Review of Ecology and Systematics. 1982;13: 111–138.
18. Jenkins S, Arenas F, Arrontes J, Bussell J, Castro J, Coleman RA, et al. European-scale analysis of seasonal variability in limpet grazing activity and microalgal abundance. Marine Ecology Progress Series. 2001;211: 193–203.
19. Underwood AJ. Effects of interactions between algae and grazing gastropods on the structure of a low-shore intertidal algal community. Oecologia. 1981;48: 221–233.
21. Johnson MP, Hanley ME, Frost NJ, Mosley MWJ, Hawkins SJ. The persistent spatial patchiness of limpet grazing. Journal of Experimental Marine Biology and Ecology. 2008;365: 136–141.
23. Lubchenco J. Plant Species Diversity in a Marine Intertidal Community: Importance of Herbivore Food Preference and Algal Competitive Abilities. The American Naturalist. 1978. p. 23.
24. Guidone M, Thornber C, Field E. Snail grazing facilitates growth of a bloom-forming alga. Marine Ecology Progress Series. 2010;420: 83–89.
26. Santelices B. Digestion survival in seaweeds: an overview. Plant-animal interactions in the marine benthos. The Systematics Associations Spec, 46,; 1992. pp. 363–384.
27. Aquilino KM, Bracken MES, Faubel MN, Stachowicz JJ. Local-scale nutrient regeneration facilitates seaweed growth on wave-exposed rocky shores in an upwelling system. Limnology and Oceanography. 2009;54: 309–317.
30. Steneck RS, Dethier MN. A functional group approach to the structure of algal-dominated communities. Oikos. 1994;3: 476–498.
35. Osenberg C, Mittelbach G. The relative importance of resource limitation and predator limitation in food chains. In: Polis GA, Winemiller K, editor. Integration of patterns and dynamics. New York: Chapman & Hall; 1996. pp. 134–148.
36. Helmuth B, Mieszkowska N, Moore P, Hawkins SJ. Living on the Edge of Two Changing Worlds: Forecasting the Responses of Rocky Intertidal Ecosystems to Climate Change. Annual Review of Ecology, Evolution, and Systematics. 2006;37: 373–404.
37. Zacherl D, Gaines SD, Lonhart SI. The limits to biogeographical distributions: insights from the northward range extension of the marine snail, Kelletia kelletii (Forbes, 1852). Journal of Biogeography. 2003;30: 913–924.
38. Littler MM, Littler DS, Brooks BL. Harmful algae on tropical coral reefs: Bottom-up eutrophication and top-down herbivory. Harmful Algae. 2006;5: 565–585.
39. Broitman BR, Navarrete SA, Smith F, Gaines SD. Geographic variation of southeastern Pacific intertidal communities. Marine Ecology Progress Series. 2001;224: 21–34.
40. Rivadeneira M, Fernández M, Navarrete SA. Latitudinal trends of species diversity in rocky intertidal herbivore assemblages: spatial scale and the relationship between local and regional species richness. Marine Ecology Progress Series. 2002;245: 123–131.
42. Hormazabal S, Shaffer G, Leth O. Coastal transition zone off Chile. Journal of Geophysical Research: Oceans. 2004;109.
43. Nielsen KJ, Navarrete SA. Mesoscale regulation comes from the bottom-up: intertidal interactions between consumers and upwelling. Ecology Letters. 2004;7: 31–41.
45. Aguilera MA, Navarrete SA. Effects of Chiton granosus (Frembly, 1827) and other molluscan grazers on algal succession in wave exposed mid-intertidal rocky shores of central Chile. Journal of Experimental Marine Biology and Ecology. 2007;349: 84–98.
46. Aguilera MA, Valdivia N, Broitman BR. Spatial niche differentiation and coexistence at the edge: co-occurrence distribution patterns in Scurria limpets. Marine Ecology Progress Series. 2013;483: 185–198.
47. Scrosati R. Regeneration and reproduction of Mazzaella cornucopiae (Rhodophyta, Gigartinaceae) after frond harvesting. Journal of Applied Phycology. 1999;10: 531–537.
48. Camus P, Daroch K, Opazo L. Potential for omnivory and apparent intraguild predation in rocky intertidal herbivore assemblages from northern Chile. Marine Ecology Progress Series. 2008;361: 35–45.
49. Espoz C, Lindberg DR, Castilla JC, Simison WB. Los patelogastrópodos intermareales de Chile y Perú Intertidal limpets of Chile and Perú. Revista Chilena de Historia Natural. 2004;77: 257–283.
51. Santelices B. Patterns of organizations of intertidal and shallow subtidal vegetation in wave exposed habitats of central Chile. Hydrobiologia. 1990;192: 35–57.
52. Rivadeneira M, Fernández M. Shifts in southern endpoints of distribution in rocky intertidal species along the south‐eastern Pacific coast. Journal of Biogeography. 2005;32: 203–209.
53. Broitman BR, Véliz F, Manzur T, Wieters EA, Finke R, Fornes P, et al. Geographic variation in diversity of wave exposed rocky intertidal communities along central Chile. Revista chilena de Historia Natural. 2011;143: 143–154.
54. Aguilera MA, Navarrete SA. Distribution and activity patterns in an intertidal grazer assemblage: influence of temporal and spatial organization on interspecific associations. Marine Ecology Progress Series. 2011;431: 119–136.
55. Hannach G, Santelices B. Ecological differences between the isomorphic reproductive phases of two species of Iridaea (Rhodophyta: Gigartinales). 1985;22: 291–303.
57. Fortin M-J, Dale MRT. Spatial Analysis: A Guide for Ecologists. Cambridge, UK.: Cambridge University Press; 2005. p. 365.
58. Manly BFJ. Randomization, Bootstrap and Monte Carlo Methods in Biology. Third. Chapman & Hall; 2006. p. 480.
59. Dutilleul P. Spatial heterogeneity and the design of ecological field experiments. Ecology. 1993;74: 1646–1658.
60. Von Ende C. Repeated-Measures Analysis. In: Schneider SM, Gurevitch J, editors. Design and Analysis of Ecological Experiments. New York: Chapman & Hall; 1993. p. 445.
61. Berlow EL, Navarrete SA, Briggs CJ, Power ME, Menge BA. Quantifying variation in the strenghts of species interactions. Ecology. 1999;80: 2206–2224.
62. Navarrete SA, Menge BA. Keystone predation and interaction strength: interactive effects of predators on their main prey. Ecological Monographs. 1996;66: 409–429.
64. Menge BA. Indirect Effects in Marine Rocky Intertidal Interaction Webs: Patterns and Importance. Ecological Monographs. 1995;65: 21–74.
65. Benedetti-Cecchi L. Predicting direct and indirect interaction during successionin a mid-littoral rocky shore assemblage. Ecological Monographs. 2000;70: 45–72.
66. Worm B, Sommer U. Rapid direct and indirect effects of a single nutrient pulse in a seaweed-epiphyte-grazer system. Marine Ecology Progress Series. 2000;202: 283–288.
67. Gorman D, Connell SD. Recovering subtidal forests in human-dominated landscapes. Journal of Applied Ecology. 2009;46: 1258–1265.
68. Littler MM, Littler DS, Taylor P. Selective herbivore increases biomass of its prey: a chiton-coralline reef-building association. Ecology. 1995;76: 1666–1681.
70. Branch G. Interspecific competition experienced by South African Patella species Journal. Journal of Animal Ecology. 1976;45: 507–529.
71. Godsoe W, Harmon LJ. How do species interactions affect species distribution models? Ecography. 2012;35: 811–820.
72. Lima FP, Queiroz N, Ribeiro PA, Hawkins SJ, Santos AM. Recent changes in the distribution of a marine gastropod, Patella rustica Linnaeus, 1758, and their relationship to unusual climatic events. Journal of Biogeography. 2006;33: 812–822.
73. Kinlan BP, Gaines SD. Propagule dispersal in marine and terrestrial environments: a community perspective. Ecology. 2003;84: 2007–2020.
74. Wieters EA. Upwelling control of positive interactions over mesoscales: a new link between bottom-up and top-down processes on rocky shores. Marine Ecology Progress Series. 2005;301: 43–54.
75. Lima FP, Wethey DS. Three decades of high-resolution coastal sea surface temperatures reveal more than warming. Nature Communications. 2012;3.
76. Gaylord B, Reed DC, Raimondi PT, Washburn L. Macroalgal spore dispersal in coastal environments: mechanistic insights revealed by theory and experiments. Ecological Monographs. 2006;76: 481–502.
77. Varela DA, Santelices B, Correa JA, Arroyo MK. Spatial and temporal variation of photosynthesis in intertidal Mazzaella laminarioides (Bory)Fredericq (Rhodophyta, Gigartinales). Journal of Applied Phycology. 2006;18: 827–838.
78. Parmesan C. Ecological and evolutionary responses to recent climate change. Annual Review of Ecology, Evolution, and Systematics. 2006;37: 637–669.
79. Sexton JP, McIntyre PJ, Angert AL, Rice KJ. Evolution and Ecology of Species Range Limits. Annual Review of Ecology, Evolution, and Systematics. 2009;40: 415–436.