DALTON, Mass. — The Biodiversity Research Institute is attempting to revitalize the loon population in Massachusetts.

 

Earlier this season, the institute deployed rearing pens at Windsor Reservoir with the goal to translocate a total of nine to 15 male chicks this season. 

 

 

The institute's rearing program puts more chicks and adult loons into the system so that they come back to specific areas to breed. They do this in two ways, by pen rearing and direct release, Loon Project Director Lucas Savoy said.

 

When pen rearing, the researchers survey areas where the loon population is strong and determine which pairs have more than one chick.

 

Once that is determined, they will return to the site after dark and retrieve one of the chicks. They will then have it evaluated by a wildlife veterinarian in the area to make sure it can travel. 

 

Prior to the trip, the research team will give the chick fluids so it doesn't get dehydrated and should arrive at the pen by 4:30 or 5 a.m. 

 

The Windsor Reservoir site has three pens that hold a single loon chick at a time. The chicks will remain in the pen for about three weeks while being cared for by the research team. The Windsor Reservoir team has a crew of five. 

 

Other captive programs and zoos showed that adult loons do not tolerate being in captivity. They become highly stressed and can develop a fungal and respiratory disease called aspergillosis that can lead to death. 

 

The institute will collect blood samples when they bring the chick to the pen and again upon release to test for stress hormones or abnormalities in blood panels.

 

Their research shows that loon chicks are much more tolerant to captive settings than adults and are not showing as much signs of stress since they are only in captivity for a brief time. 

 

When the institute captures the chick they are between 6 to 14 weeks old and when they are just starting to catch food on their own.

 

"So, we can bring them to the pen. We can release minnows in their pen and are able to catch their own fish and they don't get nearly as stressed," Savoy said. 

 

During the direct release process, the research team will visit lakes where the loon chick population is strong and catch chicks that are at least 9 weeks old but are still with their parents. 

 

"So, those birds don't need to go to the pen at all. They're completely independent. They're still with their parents, but they can catch their own food," Savoy said. 

 

"They're harder to catch, but we do catch them in Maine, and then they're driven to Massachusetts and just let go in the lakes that night."

 

Once the loons fledge in the freshwater lakes, they will migrate to the ocean where they will remain for approximately two to five years. Only 50 percent of the loons make it back to the lakes to breed. 

 

The institute released 48 loon chicks in eastern Mass over the course of 2016 through 2017 and out of those 48, they have observed 24 coming back to those lakes.

 

"When we started doing this in 2015 in the eastern part of the state, we're now starting to see those birds come back as 5, 6, or 7-year-olds, coming back to eastern Mass and starting to form pairs and breed," Savoy said.

 

"The program is doing very well. We won't know the success of the Berkshires, like I said for a few more years because we just started moving chicks there last year in 2022 but given our success in the eastern part of the state we don't see any reason why it shouldn't do well in the western part of the state too."

 

A loon can live upwards of 30 to 35 years. 

 

Having loon chicks in an area enhances the water system and fisheries because they eat fish or crayfish that are easy to catch. 

 

They will typically eat the warmer water fish, like perch and sunfish, rather than the colder water fish like trout and salmon, Savoy said. 

 

"They will eat trout and salmon for sure, don't get me wrong, if they can catch them they will but typically the warmer fish or the slower fish are easy to catch," he said.

 

They are also eating the fish that are surviving but have some issues, whether its form a disease or malfunctions. 

 

"They're kind of culling off some of those fish that are maybe compromised a bit and loons typically are found on some of the most prestigious fisheries throughout New England. So, loons are known to not impact local fisheries; they actually can enhance them," Savoy said.

 

The state had lots of loons in the late 1800s but they were wiped out by the 1900s because of hunting. 

 

"Loons just take forever to come back on their own. They don't disperse well, so when they do come back to an area they don't expand very quickly on their own," Savoy said. 

 

Although loons could still be seen in the area it became a rarity — the population was struggling.

 

There are only 50 pairs of loons condensed in the central part of the state, Savoy said.

 

Unpaired loons could still be seen in the eastern part of the state, indicating that the habitat was still viable, however there were not enough of them to form pairs on their own. 

 

"On the eastern part of the state there were not any pairs at all of loons, but we would see adult loons there that were unpaired, so we knew that the population was trying," Savoy said 

 

"... at least in the eastern part of the state, we knew that habitat was good. It is attracting loons, it's just not attracting enough loons to jumpstart a population."

 

The western part of the state is a little more advanced, Savoy said. Not only did the area have some single loons, it also had two existing pairs that were producing young on their own. 

 

But loon pairs do not hatch chicks consistently every year. 

 

"They might go two or three years without fledging a chick and then they might fledge a chick and then that chick has a 50 percent chance survival rate of coming back as an adult," Savoy said. 

 

"So there just wasn't enough chicks being hatched in the western part of the state to kind of formulate that population."

 

To prevent history from repeating itself, the common loon is currently listed as a "Special Concern" under the Massachusetts Endangered Species Act so there is a severe penalty if someone is caught killing or harming a loon. 

 

More information on the project here.