DNR to study Gulf oil spill's effect on Minnesota loons
BROOKLYN CENTER, Minn. -- Most of Minnesota's adult loons and pelicans had flown north before last year's Gulf oil spill struck, but many of their offspring remained behind in the slick.
Now, state bird lovers and natural resource managers are anxiously waiting to see how many loons and pelicans return to Minnesota in April and what impact the oil spill had on two of the state's iconic water birds.
"The loons that hatched in Minnesota in 2008 and 2009 were in the Gulf during the entire spill. They usually don't make the trip north until their third year," said Carrol Henderson, nongame wildlife supervisor for the Minnesota Department of Natural Resources.
Pelicans, he said, also spend their first summer in the south.
"Did they make it through? Will fewer of them come back to Minnesota?"
No one knows the answer yet, Henderson noted, but the DNR and other experts have moved quickly to develop a loon and pelican plan in recent months "so we didn't have to guess what the spill means for our birds."
DNR officials hope this spring to begin an intensive, $250,000 study on the impact of the Gulf spill on the two state bird species scientists determined are most likely to be impacted. They outlined the plan Friday at the agency's annual "roundtable" convention in the Twin Cities.
The money was approved last summer while the oil was still flowing by the Legislative and Citizens Commission on Minnesota Resources. The 2011 Minnesota Legislature also must approve the funding, which comes from the state's Environmental Trust fund stocked by state lottery profits.
Lawmakers can't use constitutionally dedicated LCCMR money to balance the state budget, so the project should be approved in coming months, said State Rep. Jean Wagenius, DFL-Minneapolis.
Even adult loons that were in Minnesota and avoided the spill last summer also may be at risk this winter, Henderson noted. Because loons can dive 200 feet to find fish, they may be feeding in areas where millions of gallons of oil settled on the Gulf floor. Their food source may be tainted or gone.
"The data seems to show that (loons) go right to the bottom to feed in the Gulf," Henderson said. "And now they're saying that's where much of the oil ended up."
BROADER TRACKING EFFORT
The state loon and pelican effort includes a deeper look at the state's loon monitoring program on 600 lakes across the state that began in 1994. But it also includes placing a dozen high-tech satellite transmitters on loons for instant tracking and fitting another 60 loons with recording GPS units to see where they've gone. Even bird experts are unsure exactly where in the Gulf loons spend their winters.
Loon blood samples also will be taken to see if oil or toxic oil dispersants show up. Experts say there may be a long-term impact on reproduction if chemicals affect mating or egg viability.
But it's the number of loons and pelicans on Minnesota lakes this summer and the next few summers that may be most telling -- seeing whether the classes of 2008 and 2009 that lived through the spill are as strong as they should be and enough to keep the state's loon population stable. Even though loons are long-lived birds, up to 30 years, losing two years of reproduction could stifle the population.
"The good news is that we have 16 years of data on Minnesota's loon population to measure from,'' Henderson said. "This shows the value of long-term monitoring so when something does come up, like an oil spill, you have something that will show you what's going on.''
Steve Hirsch, director of the DNR's Ecological and Water Services division, said results from the study could put Minnesota in line for reparations from BP to recover the value of waterfowl lost to the spill.
Henderson said the state wants anyone who notices fewer loons on their lake to contact a DNR wildlife office. But "even though they comeback at age 3, they may not mate until age 5 or 6, so it may be years before the decline shows up as a decline in nesting pairs; before we know the impact of the spill.''
Minnesota has about 12,000 loons and their population has remained relatively stable over the last decade despite threats from shoreline development, lead poisoning from fishing tackle and collisions with boats. The state has about 30,000 pelicans, and their numbers have been increasing. At least 80 percent of Minnesota's loons winter in the Gulf.
Officials now estimate about 250,000 birds of all species perished directly during the oil spill, which started April 20 and lasted through July 15 during which time more than 205 million gallons of oil is estimated to have spewed from the Deep Horizon offshore oil well.
Only 100 loons have been found dead so far, Henderson said. But because loons tend to sink when they die, rather than wash up on shore, it may never be known how many died directly from the spill.