By BRENDAN SORRELL, FOR THE LACONIA DAILY SUN
MOULTONBOROUGH — Loons capture the public's imagination through their distinctive red eyes and far-ranging calls. Their plumage is also distinctive, and they have small numbers of chicks at a time, often carried around on their parents' backs. These lake-dwellers are loved by many people, but are also an important waterfowl because they occupy a position near the top of the food chain in aquatic areas, allowing the researchers who study them a good look into the health of their ecosystems.
Concern was expressed for the birds recently by Jim Haney, a professor of biological sciences at the University of New Hampshire about their exposure to high levels of liver and neurotoxins.
"We are examining whether this nerve toxin may be contributing to the recent disappearance of the Common Loon from certain New Hampshire lakes," said Haney. "Levels of BMAA, a toxin suspected to be related to human neurological disorders such as ALS, also known as Lou Gehrig's disease, were highest in the chick feathers. This suggests these birds have been exposed to relatively high concentrations in fish they were fed by their parents," said Haney, who also directs the UNH Center for Freshwater Biology.
UNH is study examining the possible role of neurotoxins that are developed in blue-green algal blooms – a type of algae that is increasing in its concentrations in lakes due to a number of factors, including global warming – in the decrease in loon population growth in recent years.
Harry Vogel, senior biologist and executive director of the Loon Preservation Committee called this release premature, as it merely stated a possible link without any conclusive findings, but also called this type of research important, as biologists are just beginning to understand the wide range of environmental factors contributing to a loon health and much more research needs to be conducted to help save loons and other species.
The algal blooms are another of the "co-occurring stressors that affect the health of our birds," he said. "There's always this sense that we want to attribute the troubles of loons to this one thing, and the reality is that there are contributions from many things."
The research, according to Vogel, is going to help, but if the findings produce a definite link between these neurotoxins and loon health they will still be just part of a chain of many contributing factors.
"Loons are having to deal with all of these factors at the same time," said Vogel. Research into every facet of the ecosystem needs to be done in order to understand what's happening to loons in order for the conservation efforts to be most effective for these beloved birds.
The Loon Preservation Committee in Moultonborough is also conducting a census of the loon population. They celebrated the birds with their annual Loon Festival last Saturday.
"This is an event to celebrate loons and our fascination with them," said Vogel. "This year's Loon Festival was another great success, and adults and kids enjoyed balloon animals by Mo, children's crafts and activities, live animal demonstrations courtesy of the Squam Lakes Natural Science Center, free hot dogs courtesy of Meredith Rotary, and a dunk the biologist dunk tank," said Vogel.
The New Hampshire State Senate named last Saturday Loon Appreciation Day in recognition of the work done by the Loon Preservation Committee with their Loon Festival and the Loon Census that operates in conjunction with it.
"The census is a one-hour event to get a snapshot in time of New Hampshire's loon population by having as many observers on the water as possible to count loons. Participants have until July 31 to mail census forms back to us and numbers will be tallied by mid August," said Vogel. It is important to count loons not just for loon health but as an indicator of the health of the ecosystem.
Since the mid-1970s, thanks in large part to environmental efforts and the work of the Loon Preservation Committee and similar organizations, the loon population has tripled in lakes in the Northeast United States, including, of course, the lakes of Central New Hampshire. A large part of this growth can be attributed to stopping the use of DDT, an insecticide that was found to be harmful to birds and other wildlife and eventually banned in the United States in 1972.
This alone is not enough to account for the loon population growth. The Loon Preservation Committee has many efforts to cultivate loon population growth in New Hampshire. The reason the Loon Preservation Committee was founded in 1975 was people noticing that the loon presence on New Hampshire lakes had been diminishing.
"Human activities were seen as causing that decline," said Vogel, "and the thought was that human intervention of the opposite variety could help to reverse the trend."
Each year, the Loon Preservation Committee has been setting new records for their involvement in aiding loon population recovery.
"We are managing to mitigate some of the negative consequences of human involvement," said Vogel. Results from the census demonstrate this, as the Loon Preservation Committee estimates one out of every four loon chicks hatched last year was born on rafts they put out for the purpose.
Although the figure of tripling the loon population since the 1970s is staggering, many lakes in Canada have triple our concentration of loons, and in the past five years our local census has reported almost no growth in the loon population.
Environmental factors of all kinds are contributing to this stagnation in growth. Two highlighted by Vogel are lead sinkers and jigs and an increase in dangerous algal blooms. Although the sale of lead fishing equipment is banned, Vogel said the Loon Preservation Committee is still finding loons dying due to lead poisoning. Everything that can be done legally and by organizations like Vogel's has already been done to stop this, but lead sinkers are still around in old tackle boxes and it is now up to the fisherman to be vigilant about what kind of equipment they are using.
Algal blooms are a different type of problem.
"If you have contaminants that increase in concentration as they move up the food chain, which loons are near the top of," said Vogel, "and also biomagnify in long-living animals like loons, increasing in their concentration in the animal over time, makes them a useful indicator of environmental health and the quality of the water."
Due to their position at the top of the aquatic food chain, loons feel the effects of these contaminants far more than other species.
An upcoming event that may be of interest to those who want to help save the lakes of New Hampshire is the 10th annual Squam Swim on Aug. 11. It's a 7-mile relay swim across the length of Squam Lake to raise funds for the research going on on Squam and help recover the population of loons on that lake.
A loon on Lake Wickwas stretches wide during preening in June. (Karen Bobotas/for the Laconia Daily Sun)
- Category: Local News
- Hits: 367