June 2016

Vol. 44, No. 3

Restore the Call: A Bold Initiative to Aid Loon Recovery

Lee Attix and Michelle Kneeland

At dawn on August 20, 2015, I held chick number one anxiously, and I’m sure my breath as well, before wading out into the lake to set him free, marking an amazing moment in history. I don’t remember if the sunrise in the east was licking my face, or if it was pouring rain. I just remember letting go, a quickened pulse, and a final glance from this historic loon chick. I consider myself one of the lucky ones, and I hope he is, too.— Lee Attix

Common Loons (Gavia immer) and those who look after their well being in the United States have reason to celebrate. There is a bold new initiative underway to help restore the breeding loon population to designated areas of their former range across the country. It is the single largest conservation project undertaken to aid loons and their recovery, and it is happening in the morning shadow of Cape Cod.

This article will discuss a groundbreaking component of the larger project, which is the translocation and captive rearing (hacking) of loon chicks, with a focus on the work being conducted in New England, particularly Massachusetts. The Biodiversity Research Institute (BRI), a wildlife conservation organization based in Portland, Maine, is spearheading the Restore the Call initiative in collaboration with the Massachusetts Division of Fisheries and Wildlife (MassWildlife). The project is funded exclusively by the Ricketts Conservation Foundation.

To provide some perspective, it is important to convey that Common Loons have been well studied and there is a lot of literature to inform us about their plight through time. Some of that literature tells us that loons were extirpated—became locally extinct—in Massachusetts and many other states across the United States as a result of human activities in the 1800s and early 1900s. Hunting loons was legal, and it was a major contributor to their demise, until the Federal Government stepped in and passed the Migratory Bird Treaty Act of 1918, protecting loons and more than 1000 other migratory species.

By all accounts, the loon population did not begin to rebound in areas of their former range until the 1970s. Map 1 illustrates how their former range shrank throughout the United States, and how dedicated conservation efforts over the last 40 years have helped the population rebound.

Review of the historical literature for Massachusetts finds that loons were officially declared extirpated in 1925, but records indicate the last known breeding pair dated all the way back to 1872, some 53 years earlier. It would be more than 100 years before another pair of nesting loons was confirmed in Massachusetts in 1975. That breeding pair was found on Quabbin Reservoir, which has become an important breeding location for loons during their recovery in Massachusetts.


Map 1. Range of Common Loon Breeding Populations. All maps and photographs courtesy of BRI staff unless otherwise indicated.

The Department of Conservation and Recreation (DCR) first began monitoring loons on Quabbin Reservoir in the 1980s, in collaboration with MassWildlife. In 1996, under the leadership of Dan Clark, Director of Natural Resources, DCR expanded the program to include more active management strategies. BRI began collaborating with DCR in 1999, and more recently with MassWildlife, on a statewide loon monitoring effort, which led up to the proposed translocation undertaking.

Since that first nesting pair was identified on Quabbin Reservoir in 1975, Quabbin has developed into the hub for Common Loons in Massachusetts. In 2015, researchers from DCR and BRI confirmed 22 territorial pairs on Quabbin, making it one of the most densely populated water bodies in all of New England. Loons have also repopulated many other lakes, mostly clustered in Worcester County in north central Massachusetts. The population trend is upward with 45 confirmed pairs in Massachusetts in 2015.

You might ask, why do loons need further management intervention? Aren’t they doing fine, and in time, won’t they be successful repopulating all of their former breeding range in Massachusetts? These are good questions.

Researchers believe that the single biggest obstacle to loons naturally repopulating a region successfully is their difficulty in colonizing and dispersing out from established breeding territories. Prior studies confirm that, on average, loons disperse only 13 kilometers (about eight miles) from their natal lake, and over 80% of the time, breeding adults return to the same territory year to year.

In Massachusetts, this presents a formidable challenge for loons to disperse out from the repopulated north central region to former breeding grounds in the Berkshires to the west. It is an even greater challenge for them to disperse to the isolated region of southeastern Massachusetts, which currently is some 55 miles away from the closest pair of breeding loons in the state (Map 2).

In some ways, the recovery in Massachusetts mirrors the rebound of loons across the United States. There are pockets of limited geographic areas where loons have rebounded well, and other areas where they have repopulated in small, disjointed numbers or not at all. This knowledge challenged BRI researchers, and led them to the bold idea of attempting active restoration—translocation and hacking of chicks— something that has been done successfully in the past with raptors and other birds, but never loons. The prospect of doing this successfully with loons presented unique challenges and risks, namely: 1) how to safely contain a loon in the water while giving it adequate space to swim, exercise, and allow it to continue to learn to forage on its own since loons eat only live prey, 2) how to feed them live prey without negative imprinting and possibly developing a reliance on human feeding, 3) how to monitor their activity and survival after release because loons in the wild forage in large areas and do not return to their nests after hatching, and 4) how to ultimately confirm that the translocated chicks return as adults to the same area to breed because loons don’t return for three years, and don’t breed until they are at least five years old. These were daunting questions.


Map 2. Distance between Wachusett Reservoir, Worcester County, and Assawompset Pond Complex, Plymouth County.

After many meetings filled with healthy debate, BRI researchers developed methods they believed could work, and in 2014, they conducted a pilot study in Minnesota. For the first time in history, Common Loons were translocated and captive reared on a lake before being released. It was an opportunity to test and refine methods, and it was extremely successful. Five loon chicks were safely translocated from northern Minnesota to southern Minnesota, reared in captivity, released in good health, and all fledged off the release lake.

The BRI research team learned many lessons during the pilot study. The overall approach proved sound, and with minor refinements, they set plans in motion to expand the project to loon conservation efforts in Massachusetts in 2015.

Let’s go behind the scenes for an in-depth look at the restoration effort in Massachusetts, and learn how BRI researchers solved the challenges they faced, and if they could match their success in Minnesota.


Common Loon chick after its release into a rearing pen. © Shawn P. Carey

Identifying The Restoration Site

Based on habitat survey assessments and historic knowledge, MassWildlife and BRI collaboratively selected southeastern Massachusetts, particularly the area of the Assawompset Pond Complex (APC), as the area to receive translocated chicks due to its value to loon restoration and excellent habitat. As a drinking water supply, much of the APC water bodies and shorelines are protected from development and human access. The Massachusetts Audubon Society designated the APC as an Important Bird Area. The lakes offer high quality loon habitat including clear water, healthy fish populations, and good shoreline nesting habitat.

Identifying Source Lakes

With the approval and cooperation of the New York State Department of Environmental Conservation (DEC), BRI researchers selected the Adirondack region of New York State as the target area for sourcing chicks for the 2015 translocation effort. Source lakes were identified by BRI biologists based on long-term studies of the New York loon population, conducted by BRI’s Adirondack Center for Loon Conservation, in close collaboration with DEC.

Capture and Translocation

Chicks that were six to eight weeks of age were captured using traditional and reliable nighttime lighting techniques, which were developed by BRI and perfected over the last several decades. Once the chicks were in hand, a BRI attending veterinarian performed a quick physical examination and then administered subcutaneous fluids to prevent dehydration during transport, which averaged about six hours in a car.


Relaxed chick in transport crate. © N. Schoch, 2015.

To keep the chicks calm, cool, and healthy during transport, BRI designed custom, opaque, plastic containers, with a mesh floor suspended from the bottom, where the chicks rested. The mesh floor served as a soft, forgiving surface to protect the chick’s keel, and it also allowed any excrement to fall away from the bird. Several two-inch diameter holes were cut in the bottom of the containers below the netting, out of reach of the bill, to allow adequate airflow into the container, and frozen ice packs were inserted to keep the environment cool. These transport boxes significantly reduced the risk of injury during translocation and helped preserve feather quality.

Much to the discomfort of the driver and passenger, the temperature in the transport vehicle was kept between 50 and 60° F to minimize the risk of heat stress in the chicks. Upon arrival at the rearing site, chicks were immediately brought to the pens, and carefully hand-released into the water in the pens, only one per pen. Chicks were usually released into the rearing pens in the early morning hours just after sunrise.

Rearing Pens

Building a structure to securely and safely contain the loon chicks in the water was extremely challenging. The BRI team had to design something to keep the birds inside while keeping potential predators outside, and it had to be sturdy enough to withstand the force of pounding waves. The solution they landed on for the rearing pens was using freestanding chain-link fence panels, similar to those used in dog kennels. Each enclosure measured 12 feet x 24 feet to give the loon chicks plenty of room to forage and exercise.


Released chick in its rearing pen.

Because the chain-link fence presents an entrapment risk for loons, all sides of the pens were lined with white polyester aquaculture netting with a 1/32-inch mesh size. The bases of the pens were open, allowing for a natural lake bottom floor. The tops of the pens were also open but covered with avian guard netting to offer protection from aerial predators and prevent other predators or scavengers from entering the pen.

Three individual pens were installed in the lake, placed approximately 60 feet from shore in order to reach an adequate water depth. The pens were positioned approximately four feet apart, to allow access for staff in between, and to give each chick some separation.

Once the three rearing pens were in place in the water, a temporary dock was erected that extended from the shore to the front of the pens, across the front of all three pens, and in between the pens. This dock arrangement allowed easy access to the pens for feeding and recapture of chicks. Two feeding blinds were constructed on the dock in between the pens. A PVC feeding pipe extended from inside the feeding blind into the pen, allowing staff to deposit live fish through the tube without being seen by the chick. This setup allowed feeding of the captive chicks without habituation to humans or creating an association between humans and food.

Feeding

Loons primarily eat fish, a lot of fish, which is true even for young chicks. BRI needed a reliable, local source of live fish. As luck would have it, the APC complex sits just a few minutes south of the region’s largest wholesale bait shop, and they carried an abundant supply of Golden Shiners (Notemigonus crysoleucas), the only native fish species available.


Three rearing pens in the lake.

When asked how much eating “a lot of” fish is, a BRI staff person on site answered that when there was a chick in all three pens, they were purchasing 15 pounds of live golden shiners per day! Fish were purchased daily or every other day, held at the rearing site in a floating fish pen in the lake, and fed to the chicks as needed.

Using the blind as a visual barrier so the chicks could not see the person feeding them, staff placed the fish into a large funnel that was connected to a PVC tube. Once in the tube, the fish slid down and dropped into the water. The end of the pipe was about two feet above the water surface. BRI researchers discovered that the chicks were stimulated by the noise of the fish dropping into the water. The loon chicks were fed using this method multiple times a day, and they would consume as many as 15–20 fish in a single feeding.

Release

The chicks were reared in the pens for various lengths of time depending on their age at the time they were translocated and how well they acclimated to the pen. The older chicks (eight weeks or older) were reared for just nine days, and the youngest chick (about six weeks old) was reared for 23 days.

Prior to release, the BRI team recaptured the chicks from the pens, gave them a full health assessment, and banded them with a unique color combination and number sequence, which allowed researchers to identify them during post-release monitoring efforts.


Rearing pen with feeding tube and blind.

Monitoring after Release

The research team found that the chicks were quick to adapt to their freedom after release. They began foraging on their own quite quickly. In some cases they foraged individually. In other cases, multiple chicks foraged as a group, which mirrors natural foraging behaviors of adults and of chicks who are becoming independent from their parents.

The on-site team monitored the chicks from shore and motorboat, using binoculars and spotting scopes. They were monitored daily for several weeks after the last chick was released, and weekly thereafter until none were observed several months later. When they could no longer observe it, the team considered a chick fledged.

Results

Given the daunting challenges the team faced, BRI considered this first year of translocating loon chicks from New York to Massachusetts an overwhelming success. Over the course of 52 days, six chicks were captured in the Adirondacks, translocated to APC, reared, and safely released. The first chick arrived on July 27, 2015, and the last chick arrived on September 17, 2015. One additional chick was translocated on September 29, 2015. It was between 10–11 weeks old and fully capable of foraging on its own, so it was released directly onto the lake with the other chicks.

Future

As of March 2016, BRI is gearing up to continue the work in 2016 and 2017, with the goal of translocating 25–30 chicks after three years. With recent verbal approval from state of Maine wildlife officials, BRI researchers will be able to source chicks from Maine as well as from New York starting in 2016.

The ultimate success of the loon recovery project will be measured by confirming that the chicks return as breeding adults and repopulate the region. That won’t be known for a few more years, which is another story for another day. Nonetheless, the unprecedented success of the first translocation phase in 2015 gives the species a chance at attaining successful recovery, which will fulfill the dreams and hopes of BRI researchers and, I’m sure, of many loon enthusiasts out there. Cheers to that!

On a frigid mid-December day, Michelle Kneeland and Vincent Spagnuolo returned to the release lake as they had done each week since releasing the last chick in late September. They were looking for chick number one, the first loon chick translocated from New York and the last chick to remain, and they didn’t see him. After a thorough scan of the lake with their optics, Vincent lowered his binoculars and said, “I think he finally left. I bet he’s already on the ocean by now.”

Michelle nodded and struggled to find the words to articulate what she was feeling. Having watched this loon grow from a small, downy-covered chick over the past four months, his departure brought relief, happiness, pride, but also a twinge of sadness. “I really hope we see him again in a few years,” was all she could say, but the weight of those words lingered as they turned to leave the lake.— Michelle Kneeland


Lee Attix is a loon conservation specialist with Biodiversity Research Institute in Portland, Maine. He began working with Common Loons in 1997 after a brief period studying raptors in the Northwest. Lee has been with BRI since 1999. In addition to his work with loons, Lee has served in many business capacities over the years at BRI, most recently as chief operating officer. In 2013, Lee returned to loon conservation work full-time, and is currently the project lead for the Commonwealth of Massachusetts for BRI’s national Restore The Call initiative.

Michelle Kneeland is a staff veterinarian and director of BRI’s Wildlife Health Program. Michelle was first introduced to loons and BRI in 2007 while working as a wildlife health and mortality research assistant at Tufts Veterinary School. She spent the following two summers as a veterinary intern for the Loon Preservation Committee in New Hampshire. Following graduation from Tufts Veterinary School in 2012, Michelle completed a one-year surgical internship at the University of Pennsylvania New Bolton Center. She joined BRI as a wildlife veterinarian in the fall of 2013. Her current work at BRI focuses on wildlife health and mortality research, conservation medicine, and overseeing the loon health and captive rearing aspects of BRI’s Restore the Call initiative.

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