Recently many plants have been threatened by the increase in invasive species such as goats, rats, cats, and pigs.
Monitoring is necessary to see what level of stress can be applied and endured.
As tourism and population sizes on the islands increase, the need for indicator species becomes increasingly important.
Currently one of the most accurate, overall method to recording plant species is to go out in the field and measure density, frequency, cover, and biomass of the particular species.
Data from plant indicators must keep in mind that depending on the plant, season, and amount of rain, populations fluctuate rather frequently.
Why should we monitor seaweeds?
Seaweeds, or marine benthic macroalgae, would be extremely useful to monitor. They could serve as indicators for changes in temperature and certain animal populations, as well as a means to detect the presence of pollutants. Having a record of the algae gives another way to measure any harm done to the environment after a storm, an oil spill, El Nino or any other irregular shifts in the ecosystem.
Although algae in general are difficult to monitor, seaweeds are easier than other algae species simply because they are big enough to be seen and handled. The individual size of the seaweed will make it easier for an estimated population size to be determined.
Seaweeds have been split into these three main groups: Chlorophyta (green algae), Rhodophyta (red algae), Phaephyta (brown algae) (Keats 2001). Other species of algae are encouraged to be researched as well, however the wide variety and size of the algae community has made them a difficult and daunting species to monitor.
How reliable are these methods?
Some say that these methods (using algae samples to access health of ecosystem) are unreliable, yet these claims are generally made because not much is known about algae species. There is great deal of information dealing with algae that scientists have yet to discover, and in an attempt to understand these processes; many researchers have done many short-term experiments conducted in a short amount of time. This methodology is effective for scientific research, but for the purpose of monitoring (and monitoring with accuracy), long term studies are crucial in order to effectively access the health of the ecosystem.
Also, much debate has been made over where the analysis should be done; should it be done on the boats directly after it is taken which might be slightly more expensive or in a lab on shore where there is a possibility for that the samples will be damaged and/or not preserved completely. Whichever method is decided upon, researchers much try to be as consistent as possible, so as to minimize the margin for error.
To make the data collected reliable, scientists will need to continually monitor the species; continually monitoring does not necessarily mean re-evaluating each individual species every single time samples are collected. On the contrary, once a baseline is established, scientists will be able to begin to specialize/concentrate on certain areas or on certain species which correlate with important factors in the environment (ex: if the size of fish populations is determined by the abundance of green algae)
Why should we monitor algae?
Algae are crucial to the survival of many organisms and may be used to access the health of the ecosystem. For example, marine iguanas feed on certain species of algae (ex: green algae such as Ulva lactuca) which generally grow in the inter-tidal zones. During El Nino the temperatures increase, and consequently marine iguana populations decrease. The increase in temperature seems to cause the edible green algae to be replaced by other species (brown algae, in particular, which is thought to be toxic to iguanas), and thus the iguana populations decline.
Another possibility lies in the fact that certain algae have a symbiotic relationship with coral reefs (some rhodophytes (red algae), for example, which have concentrations of calcium carbonate in their cell walls). (Keats 2001) When the algae die (ex: during El Nino), the reefs begin to die as well, and when the algae are replenished, the reefs come slowly back to life.
Much is still to be learned about algae and the many roles they play throughout the environment. Since algae are eaten by crabs, fish, and marine iguanas, as well as being basic components to building coral reefs, they are extremely important to monitor if we intend to truly understand the environment.
First the basic information is needed. Researchers need to know what species are currently located on and around the Galapagos Islands. This way they will be able to measure change and access damage (if needed) in the environment. There needs to be a baseline or a control before we start making assumptions about the kinds of roles algae play in the ecosystem.
What are some reasons to monitor algae?
Algae are essential building blocks of the food web -- ex: algae are eaten by fish and crustaceans which are in turn eaten by birds, sea lions and similar predators. Many algae species are not currently being monitored. Scientists are still researching the full range of potential with algae since many of them have been found to be important medicinally (especially used in Asian countries), commercially, and as a food source.
Algae are also good environmental indicators as far as changes in temperature, nutrient-concentrations (for example, certain elements which play a direct role in algae life cycles may be worth monitoring; elements such as oxygen, nitrogen, phosphorous, and carbon dioxide)
What are some of the reasons not to monitor algae?
Algae are hard to identify even well-trained botanists have trouble identifying a few of the species (some algae only differ in cellular structure, reproductive methods, etc). In order to establish a baseline, this problem must be addressed or at least considered.
Generally destructive methods are used for monitoring. Usually researchers take the entire plant so they can analyze it in its entirety. This is necessary for the identification of some species. It is collected it using scuba gear, submersibles, or collected by hand with metal scrapers if the algae is being taken in shallow water. Samples should not be collected from pieces found drifting on the surface or after they have been washed up on shore. The main reason for this is that these samples are often damaged or decayed, and their precise original habitats are unknown. (Chopin 2001)
Nondestructive methods can be made only after a baseline is created (after using destructive methods), and even then these methods (for example, trying to measure pH to determine size of algae population) arent reliable as sole indicators factors like these are rare. Simple nondestructive methods are not usually trusted by scientists because algae are extremely diverse, and it is unlikely that one factor will record every detail necessary to monitor the species effectively. (Chopin 2001)
How will the algae be monitored?
First, as was mentioned earlier, needs to be established. Scientists need to know what is already out there before other measurements are taken into consideration. A possible way to do this is to make a basic plot of the area to be monitored (series of grids of approximately 200 square meters each -- grids can be re-fitted if this size is inconvenient for more diverse areas), then the scientists conducting the research would be able to travel through each grid and identify all the necessary species of algae.
After a baseline has been established, then a few remote sensing data pictures can be used to estimate some of the algae species visible on or close to the surface so scientists have a way to make a quick, rough estimate.
What are we going to do with the information?
Numerous animal and plant species are declining after each el Nino, and this has been the case for many hundreds of years. However, what scientists are worried about today is the fact that after each decline comes an increasingly long recovery period. In the past, the animals recovered rapidly to their normal population size, but now they are taking increasingly long amounts of time to repopulate and reproduce to their original levels. This is one major reason why monitoring the Galapagos is so important. Scientists are struggling to understand why this is happening so they will be able to minimize the effects, and ideally restore the Galapagos to its natural healthy state.
Humans have no control over El Nino or volcanic eruptions, but they can stop or curve pollution and over-exploitation of natural resources, as well as other problems mainly caused or created from human impact. The goal is to find out what and how humans-related actions are exacerbating the stresses (ex: El Nino) that naturally occur in this fragile environment, then try and fix them.
For instance, marine iguana populations decrease when certain kinds of algae (brown algae Phaephyta) flourish. Once the problem is identified, scientists can use that information and create a solution. Once they find out exactly which kinds of algae are decreasing iguana populations, they can then look for a creative, resourceful solution. (Charles Darwin Foundation 1999) An example in this case would be testing to see if some of the harmful seaweeds are at all useful to humans medicinally, commercially or as food sources, and if they are, then they might be gathered, and benefit both the human and environmental aspects of the ecosystem.
- Chopin, Thierry. Marine Biodiversity Monitoring; Protocol for Monitoring of Seaweeds" http://www.eman-rese.ca/eman/ecotools/protocols/marine/ seaweeds/intro.html 5 February 2001.
- "Dynamics of the Algal Communities." Charles Darwin Foundation 1999 Annual Report, PROJECTIONS. Published in April 2000.
- Keats, Derek W. and colleagues "Welcome to the World of Algae" - 21 September 2001
- Linnaeus, C. (1753). Species plantarum. Vol. 2pp. 561-1200 (+ 1-31) Stockholm.
- "Update on the El Nino Phenomenon" from Charles Darwin Foundation. March 1999
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