Thursday, May 25, 2006

Bald Eagle Researchers in Maine

I want to give all of you a brief history of three folks responsible for eagle research and management in Maine since the late 1960's. Frank Gramlich was the man who encouraged many of us to work with eagles in the early days. Frank just passed away last month. He was a WW II vet and returned to the University of Maine (UM) for his BS and MS degrees in Wildlife Management. He then worked for the USFWS in animal damage control for his entire career. He had a passion for birds of prey and you could always find a menagerie of birds in various stages of repair in his barn. He began the first systematic areial survey of bald eagles in Maine in the late 60's with the federal pilot, Bill Snow, and also established a voluntary landowner agreement to help protect nesting sites. In addition, he initiated the egg transplant program and later the transplant of young eaglets into unsucessful nests in Maine. He and I became friends in 1970 and he encouraged me to seek funding for a graduate student (Charlie) to study the status of Maine eagles. In early 1980, Frank and I were expert witnesses for the USFWS against a proposed oil refinery in eastern Maine, the location of the last vestige of eagles at that time in the northeast. In Boston, Frank was ruthlessly examined by a team of lawyers for six hours and had significant medical problems because of that event. The EPA judge was later removed for his conduct of the hearing, but Frank never recovered his health. Frank was our mentor for more than 30 years.

Charlie Todd was that new gradute student fresh from the University of Richmond who was assigned the job of determining the population status, nesting chronology and status, food habits, summer and winter distribution and everything else about Maine eagles! Truly a monumental task and worthy of a PhD but Charlie just wanted a MS degree. State and federal biologists, volunteers, UM honors students, technicians and many more all pitched in to make his a classic study. It was at a time when our population and nesting success was at rock bottom and Charlie pulled it all together for us and charted a path for recovery. At that time every eagle was priceless and we went to extreems to return every injured bird back to the wild. The picture below of Charlie holding an immature eagle illustrates this. We taught one legged eagles how to forage, rebuilt wings, with the help of local falconers, using feathers from dead eagles, repaired broken bones and then returned all of these birds to the wild. Bart, a male eagle with a lost wing, went into every classroom in Washington and Hancock Counties, as part of an education program. Perhaps the toughest job Charlie had was conducting a winter survey of eagles along the entire coast of Maine, thousands of miles of flying. We wanted to know if there were particular concentration areas that needed special protection. It was long and very dangerous work, and we had two pilots on board at all times. Flying at a few hundred feet, following the coastline around islands and pennisulas, was flying at its very worst. We hired several technicians who made it from Bangor to Ellsworth before we had to land and call a car to pick them up! On the other hand, we finally found Tim Stone, who would sit in the back of the plane and eat onion and liverworst sandwiches and be in heaven! Charlie went on to join the nongame and endangered species group of the Maine Department of Inland Fisheries and Wildlife (MDIFW), where he resides today. No one knows Maine eagles better than Charlie and he is unquestionably one of the top eagle biologists in the country. We are fortunate to have him directing our state program. Since he is still up flying I can sneak these comments onto the Blog without his editing!!

Mark McCollough came to UM from Penn State. He completed a MS studying shorebird migration in eastern Maine and then joined me on a PhD project looking at the population dynamics, particularly survivorship, of eagles. As we obtained more contaminent data on eagles and their eggs, it became obvious that we could not influence nesting success in the near term, except to reduce disturbance at nest sites. DDE was slowly working itself out of the system and it was only a matter of time before its influence would decline (as we have already seen). On the other hand, we had some of the highest PCB and mecury (Hg) levels in the country. PCB's are banned and should decline slowly but Hg is still coming in by air from the large power and industrial centers in the midwest. Hg accumulates in fish. Our inland nesting birds feed more on fish than our coastal birds, thus Hg is more of a problem on inland lakes. EPA and others have been reluctant to impose tighter restrictions on air emmisions thus our problem continues. Better air quality from the midwest is crucial to better human and wildlife health in the northeast. But back to Mark. We knew that most of our immature eagles left Maine in the fall and returned in subsequent years. They were accumulating contaminents that influenced their future breeding success. What if we could provide ample clean food to our young birds and keep them here in Maine? This should improve their survival and improve breeding success in the long run. So Mark established several feeding stations along the coast where we delivered 100,000's of pounds of clean food over a series of years. Mark ran the show; collecting beaver, deer, moose, cow, horse, chicken, etc carcases, butchering and distributing them. Stories abound like losing a truck load of chickens on the main street of Ellsworth but Mark held firm. To see how effective the feeding program was Mark built observation blinds at the sites. All winter long he'd crawl into these before dawn,wrap up in a sleeding bag, and observe birds with high power telescopes. Immediately he realized he could read the band numbers on the legs of the eagles. We had been banding all of the nestlings in Maine for several years so he was able to get a handle on who was out there. To facilitate this we added specially numbered band tags and an additional band on the other leg. We did this for several years and Mark was able to read these numbers easily. To Mark's surprise and our joy we found that the youngsters were remaining in Maine and surviving at a much higher rate than we had anticipated. Mark was able to show that this was a key factor in initiating our population recovery. At the feeding station Mark was able to read the band numbers of eagles from Cape Briton Island, Chesapeake Bay and as far away as Saskatchewan! Eagles were mixing over large geographic regions, an important genetic consideration. Mark went on to join Charlie in the endangered species/nongame group of MDIFW and recently joined the USFWS as an endangered species biologist here in Maine. We couldn't ask for a better pair of biologists looking after our endangered species.

Monday, May 15, 2006

Maine Inland Fisheries and Wildlife eagle biologist Charlie Todd.

Is it time to take the eagle off the Endangered Species List?

All endangered species biologists hope that sometime in our career we will have the satisfaction of saving a species from extinction. After all, recovery of imperiled species is our highest work priority. We put our heart and soul into these efforts. Sadly, we spend more time adding species to state and federal endangered species lists that taking species off.

State and federal biologists and many other partners have been working diligently to save the bald eagle since it was added to the first federal endangered species list in 1967. When Rachel Carson wrote her book Silent Spring about the dangers of DDT and other pesticides in our environment in the early 1960s, bald eagle populations had declined to fewer than 500 pairs in the lower 48 states. Eggshell thinning and embryo mortality from DDT extirpated bald eagles from most of the Northeast, and their last stronghold was a tiny enclave of 27 pairs in Down East Maine. In 1972, the federal government banned DDT. In 1978, the bald eagle was listed as endangered throughout most of the lower 48 states. As DDT began to slowly diminished in the environment, numerous recovery programs were initiated to save our national symbol including purchasing nesting habitat, research to address threats, and restoring eagles to former habitat. The bald eagle quickly became a poster child for the growing movement to save endangered species, and the effort payed off. By the 1980s, bald eagle productivity slowly began to improve, and some populations increased at rates exceeding 10% annually. Today, the bald eagle population has grown to over 7000 pairs in the lower 48 states. In 1995, eagles were "downlisted" from endangered to threatened status.

Today biologists believe that bald eagles are secure enough to remove them entirely from the federal endangered species list - a real conservation success story. In February, 2006 the U. S. Fish and Wildlife issued an official proposal to delist the bald eagle. You can read all about our delisting plans and the amazing recovery of the bald eagle at a new bald eagle web site

Bald eagles in Maine increased from 29 pairs in 1962 to 385 pairs in 2005. This represents a growth rate of about 7-8% annually. Although impressive, eagle recovery in Maine still lags behind other regions. DDT takes much longer to break down in our cold, northern soils, and we still find traces in unhatched eggs. A healthy eagle population produces an average of one eaglet per active pair. Maine did not achieve that milestone until 1998, and even in recent years we often fail to meet that benchmark. Other contaminants, including mercury, PCBs, and dioxin are still of concern and likely depress productivity in some parts of the state. Despite the lower productivity, survival of young ealges is good and our eagle population continues to increase and expand to occupy their former habitat in northern, western, and southern Maine. At the time of European contact, Maine likely had more than 1000 pairs of eagles. We believe that we still have the habitat to support over 600 pairs of eagles, and the population will continue to grow. Maine Inland Fisheries and Wildlife has met all of the state recovery goals for eagles, except one - to secure a "safety net" of 150 nesting areas in conservation ownership, easements, or cooperative agreements with landowners. Loss of waterfront habitat to development is a persistent threat that needs to be addressed if we are going to continue to support a vibrant population of eagles in Maine. The state is close to meeting its nesting conservation goal, and it is likely that Maine will remove the bald eagle from the state list in the near future.

What happens to a species after it is delisted? Do delisted species still get any protection or conservation funding? Both the U. S. Fish and Wildlife Service and Maine Inland Fisheries and Wildlife will continue bald eagle conservation efforts long after Charlie and I retire. Once the bald eagle is delisted the Bald and Golden Eagle Protection Act (BGEPA), passed in 1940, will provide a level of protection for eagles similar to that provided by the Endangered Species Act. The Eagle Act protects bald eagles from take, possession, or sale of a bald eagle or its nest. As part of our delisting proposal, the Service developed a definition for what it means to "disturb" a bald eagle in the BGEPA and issued draft national bald eagle nesting management guidelines. We are seeking public input on our delisting proposal and changes to the BGEPA. Comments from the public will be accepted until June 19 (see the web site above for all the details concerning the delisting proposal).

Also, after the eagle is federally delisted, the Service is committed to funding at least 5 years of population monitoring. Charlie and I have both participated in developing new eagle monitoring surveys that will ultimately be used to monitor the health of the eagle population in the lower 48 states for decades to come. If the eagle, or any other delisted species, begins to decline, we always have the option of placing it back on the endangered species list. With continued conservation we hope that populations continue to grow and the eagle will never need to be listed again.

There are many who deserve credit for the recovery of the eagle in Maine. We thank landowners who voluntarily (and sometimes adamantly) protect "their" eagle nest and sometimes make significant sacrifices to do so. The Maine Chapter of The Nature Conservancy, Maine Coast Heritage Trust, and many other local land trusts have helped protect a "safety net" of eagle nest sites. The Land for Maine Futures Program and federal expansion of the Maine Coastal Islands National Wildlife Refuge helped purchase many coastal eagle nesting islands. We owe a debt of thanks to Dr. Ray "Bucky" Owen, professor emeritus and former Department Chair at the University of Maine wildlife program, for advising a succession of graduate student research projects that helped to address the threats facing eagles in Maine. Federal biologist Frank Gramlich, who recently passed away, led Maine's early efforts to protect eagles, especially when populations were on the brink of extinction and threatened by a major oil refinery proposal on the coast of Maine. Perhaps more than anyone else, Charlie Todd, MDIFW eagle biologist, deserves much of the credit for recovery. Charlie came to Maine as Bucky's first eagle graduate student 29 years ago and has led Maine's eagle recovery ever since. Its rare that a biologist has the opportunity to participate in a species' recovery from the dark hours of listing to the success of recovery, but Charlie has been there to participate in recovery from beginning to end. Maine's bald eagle habitat protection program is nationally recognized and has struck a successful balance between protection and private land stewardship.

There are hundreds more to thank for the recovery of eagles in Maine, but the common thread in eagle delisting is that we can save wildlife from extinction if we all work together toward a common cause. Each of you has something to contribute to help endangered species, whether it is purchasing a conservation license plate, joining the local land trust, or communicating with your representatives in Congress about the importance of the Endangered Species Act.

Make endangered species a vivid presence in the lives of people. Make it clear that every endangered species has name, has a million-year history, has a place in the world. Bring us face-to- face with each of those species. Make us know that they are companions in the biosphere. They are not just something out there you look at once in a while, but they're part of our existence...they are part of us. E.O. Wilson

This is what we hope to accomplish in our careers as endangered species biologists. We hope this web site helps bring this conservation message home to you.

Mark McCollough, U. S. Fish and Wildlife Service

Monday, May 08, 2006

May 8 Notes - Bald eagle surveys

For the last 25 years, Charlie Todd, eagle biologist with Maine Department of Inland Fisheries and Wildlife, has completed annual surveys of Maine's eagle population. (In fact, he's in the air flying as we write this!). Eagle surveys provide us with vital information on the size and distribution of the population. Survey data are crucial for conservation programs and are used to track the recovery of the population. Surveys also provide important information on the health of the population - how many young are born, where we might recover an unhatched egg for contaminants analysis, or where nests are located in relation to proposed projects.

Eagle surveys are done with and amphibious float plane twice each year. The first flight begins in March on the coast where eagles nest earliest. These flights extend into May in northern Maine where we often still have snow on the ground this time of year. Biologist develop a "search image" for eagles and their nests as indicated in the photo above. With practice, the white head and tail of the bald eagle can often be discerned in a white pine at quite a distance.

Eagle nests are large, and sometimes snow in the nest bowl in late winter will reveal the location of a new nest. Bald eagles most frequently nest in our state tree, the white pine. Sometimes eagles will take over an osprey nest. Eagle nests are usually under a canopy of branches, and biologist have to search carefully - a difficult proposition when flying at 120 miles an hour. Sometimes we observe eagles flying along a lakeshore or coastline. From a distance we'll circle in the airplane, watch the birds, and follow them to a new nest location.

Eagles mate for life, and many pairs use the same nest year-after-year. The flight plan always calls for checking known nests first. If a pair is missing, we may spend time searching the nearby stands of pine for a new nest. Nests are abandoned for a number of reasons - disturbance the year previous, a mate change, or a nest damaged by a winter storm. The public notifies the state and federal agencies of new nests and eagle activity in areas where eagles had not been observed before. These tips are very helpful in finding new territories. When "deadheading" from one territory to the next, we often ask the pilot to skirt a lakeshore. Every minute in the air counts, and often new nests are located in this fashion.

All nests with an adult pair present or incubating are considered "occupied." In the photo above, one eagle is in an incubation posture and the mate is perched nearby. In June all occupied nests are surveyed a second time by airplane to document how many chicks were produced. We try to time the second flight when the eaglets are about 8 weeks or older. At this age, the chicks are starting to get their brown feathers. Most of the chicks observed at this age will survive to fledge later in the summer. As we've observed with the web camera, attrition can occur between hatching and fledging.

Sometimes special flights are made to survey nests more intensively, especially when documenting the age of eaglets for banding or locating unhatched eggs. Several paper company in Maine are helping the state and federal agencies to monitor contaminants in nests close to their paper mills. These nests are flown every week early in the nesting season to search for abandoned nests with unhatched eggs. Biologists collect unhatched eggs to measure contaminants. We have to promptly retrieve unhatched eggs. Crows and other scavengers quickly consume eagle eggs not attended by the parents.

Flying is interesting, but hard work. State and federal pilots have to be well-trained and experienced to fly all day at low altitude and in tight turns around the nests. Biologists have to maintain their concentration and data-taking skills despite working under high G-forces in a loud, hot cockpit. Sometimes, on breezy or turbulent days, Charlie and I crawl out on to a lakeshore or tarmac for a lunch break and wish we could walk home rather than face an afternoon of more flying. On the positive side, we've seen nearly all of the state of Maine, and the scenery and wildlife sightings are incredible. The pastel blush of trees leafing out on the mountains and hills of Maine in May rivals the riotous fall colors.

Last year, Charlie found 385 pairs of eagles nesting in Maine. We use the ratio of young fledged per occupied nest as an index of the health of the population. In a good year, bald eagles should produce about one chick per occupied nest.

As our population continues to climb, there may come a time when we can no longer afford to fly every eagle nest annually. The U. S. Fish and Wildlife Service and U. S. Geological Service - Biological Resource Division are developing a new survey protocol that samples a random, representative sample of the population. If the bald eagle is delisted from its threatened status, we may begin this survey methodology in the future.

Charlie Todd, Maine Inland Fisheries and Wildlife
Mark McCollough, U. S. Fish and Wildlife Service

Thursday, May 04, 2006

May 4 Notes "and then there were two..."

Regular observers are aware by now that only the oldest two of three eaglets now occupy the nest. From notes submitted to this web page about six days ago, the largest chick likely killed the youngest. We've been watching closely to see a third chick, but haven't for almost a week. As we reported in our biologist's notes, siblicide is a natural occurrence for bald eagles and other birds of prey. What you are observing on the web camera is unedited, unsanitized, real-time nature - survival of the fittest. If you have been lucky enough to observe a feeding bout, you have a sense of the intense competition between the siblings.

Fish, birds, and other animals are being killed by the adults several times daily to feed the hungry chicks. At this age, the adult eagles are still feeding the chicks, but soon the chicks will start to learn how to feed on their own. Adult eagles require about one pound of food each day. The demands of both adults and growing chicks require several pounds of prey are procured daily. Predation is a natural part of the cycle of life. Life in the nest can be a tough experience and we may loose other chick(s) before this nesting cycle is completed.

I just finished watching a feeding this afternoon. The oldest "A" chick is noticebly larger and more aggressive. Naturally it elbowed its way to be fed first. The "B" chick is smaller and had to wait its turn, but both received a full meal. Both of the remaining chicks seem to be growing at a normal rate. You can determine if the chicks have been fed recently by looking to see if their crop is full. The crop is a food storage organ, which when full creates a bulge at the top of the chest (just under the beak). Adult eagles often consume dead animals (or carrion), which are often too large to carry away. The crop allows birds of prey to consume a large meal and fly elsewhere to digest at their favorite perch.

We received an interesting inquiry from Maggie, a second-grade observer from Bangor, Maine, about eagle cleanliness. After feedings, watch for the young eaglets to back up to the edge of the nest to defecate. This is the eagles' way of keeping a clean nest. The whitewash, or "mutes" as they are called, begin to cover the ground below the nest along with a collection of fish carcasses and bird feathers. The adult eagles still rearrange sticks in the nest and toss uneaten carcasses over the side. Some of the uneaten prey gets buried in the nest bowl. The chicks are getting to an age where they may play with an eider duck wing or fish tail. As the chicks get older the nest platform will be well-trampled by their activity. The adults will continue to freshen the nest periodically with a sprig of white pine.

What kinds of prey are these bald eagles bringing to the nest? We'd like to hear about your observations. For years, we gathered food remains at the base of eagle nests to better understand eagle diets in Maine. Over the years Charlie Todd identified 64 different species of vertebrates. Fish made up more than 75% of remains and were the predominant prey at inland nests. Coastal sites relied more heavily on birds and mammals. When we installed the web camera in mid-winter we found the remains of eider ducks and cormorants at the base of the nest.

Coastal eagles feed at a higher level on the food chain than interior birds. Fish-eating ducks (like mergansers) and cormorants have higher contaminant loads than fish. Thus, our coastal eagles have a greater likelihood of accumulating contaminants like PCBs and DDT. Even at this age, the young chicks in this nest already have detectible contaminants in their blood. They received some contaminants in the egg, but are receiving additional contaminants from their food. We will write more about contaminants and how they affect eagles in future biologists notes.

Mark McCollough, U. S. Fish and Wildlife Service