Our Neighbors: The Bald Eagles A Closer Look the Bainbridge Island Locals

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1 Our Neighbors: The Bald Eagles A Closer Look the Bainbridge Island Locals ABSTRACT This study examines a portion of the Bald Eagle population on Bainbridge Island, Washington. I wanted to determine whether there is a steady population on the island, and if so, how long they have lived here and how territorial they are. I was able to observe three nests and two distinct adult pairs, although there are approximately seventeen reported nests on the island. Further research led me to the West Sound Wildlife Shelter where I witnessed three Bald Eagles in their rehabilitation facility; each eagle was a Bainbridge Island resident. Overall, I discovered that there is a diverse and steady population of Bald Eagles here on the island. INTRODUCTION The Bald Eagle is also known for its scientific name, Haliaeetus leucocephaus, which means sea eagle and white-headed respectively, and is more commonly called a raptor, or bird of prey (Gordon, 1991). According to Feduccia, eagles fall into the Falconiformes order and Accipitridae family along with hawks, Old World vultures, and Kites. Raptors are easily distinguished by their sharply hooked beaks, topped with a soft mass called a cere, which serves as the birds nostrils. They also stand out for their sharp, hooked talons and opposable hind toe (Feduccia, 1996). At a glance, one can pick out a perched Bald Eagle by its bright white head and tail and heavy yellow bill, although juveniles will stay brown with white speckles until about age five

2 (Kaufman, 1996). They are large raptors, females usually larger than males: according to the National Audubon Society (1994) they can reach approximately long with a wingspan anywhere from I have been able to identify their call by the high-pitched, rolling notes when communicating with one another; it can resemble a gull at times. They are often perched in the highest trees, often a Douglas Fir or similar, near a body of water such as the Puget Sound or a harbor. Known as sea eagles, their diet consists mostly of fish, however they will also eat carrion and crippled or young waterfowl (National Audubon Society, 1994). I have also witnessed these raptors stealing food from other birds. Bald Eagles are found near coasts or bodies of water from Alaska, across to Newfoundland, and as far South as Mexico according to the National Audubon Society (1994). Kaufman (1996) notes that they will begin to mate at around age four or five, and most will stay with their partners for life. He also states that the pairs will build nests in the highest trees in a particular area, made mostly out of sticks, which can be used for years; Bald Eagles often copulate yearly. Although there is a steady population in certain regions in North America, it is important to note that Bald Eagles were near extinction at one time due to human interference. They are extremely sensitive to human presence; for example, a Bald Eagle might avoid fishing or hunting if people are around according to Savage (1987). Savage also notes that logging and clear cuts

3 have diminished habitable conditions, since most of the eagles prefer Old Growth trees for their massive nests. Finally, numerous studies have reported that lead and DDT contaminated fish are in turn poisoning the eagles. Even though there have been threats to habitat and diet, human awareness and conservation efforts encourage a promising future for the Bald Eagle. METHODS In order to obtain information about the Bald Eagle population here on Bainbridge Island, I made observations and took notes of their location and behavior. I also interviewed Michael Pratt, Director of Wildlife Services at the West Sound Wildlife Shelter on Bainbridge Island. RESULTS Below is a sample of my observations on Bainbridge Island, WA DATE # EAGLES LOCATION BEHAVIOR 9/26/10 1-adult Eagle Harbor low tide Perched on piling eating fish or other sea food Early afternoon 10/20/10 2- adults Eagle Harbor high tide Perched in Hemlock tree near harbor 12/16/10 2- adults IslandWood Two eagles soaring above main campus in Early afternoon 1/30/11 4-adults Restoration Point Two eagles perched, another pair circling area, lots of noise/calling to each other, finally the flying pair left 1/30/11 1- juvenile Restoration Point Flew past spot where previous pair was perched 2/1/11 2- adults Mac s Pond, IslandWood Field group witnessed two adults circling pond, one swooped down to catch something in water, Great Blue Heron was scared away 2/5/11 2- adults Fay Bainbridge Perched near nest One eagle left perch to snatch food from gull, gull chased eagle, eagle perched in different tree to eat

4 This map was posted at the West Sound Wildlife Shelter: it is a chart of the confirmed Bald Eagle nests on Bainbridge Island. After looking at this map I located three nests: one in Fay Bainbridge, one on Eagle Harbor near between New Sweden Rd. and the harbor, and one on the southeast part of Blakely Harbor.

5 There is a pair at Fay Bainbridge that, according to Pratt, has had three nests in that area, although one nest was taken over by Osprey. I have consistently observed them in the same tree as one particular nest since mid-january, which seems to indicate they have chosen their nest for this year. They spend a great deal of time in and around the nest during the day, taking turns fishing or flying east over the Puget Sound to the northern Seattle area. I did observe a juvenile fly into this territory in mid-january, around the 18 th. The existing pair did not welcome this invasion. It resulted in one of the adults swooping from above towards the juvenile with loud shrieks; while I believe this to be a fight I did not witness the action, which was in the trees. I have only seen a solo eagle near the Eagle Harbor nest, but I have seen at least three different eagles in the Eagle Harbor inlet near the Eagle Harbor Rd. and Wyatt Way intersection. There has been a pair perched in the Hemlock and Douglas Fir trees near the water, and I have also spotted a solo juvenile. Blakely Harbor has one eagle that is consistently perched near a nest on the southern part of the harbor. I have not seen a pair yet, however I did see a juvenile flying over the harbor in the early afternoon on February 1, A little farther down the road, towards Restoration Point, I have noted a pair on two different occasions; one time was noted in the chart above. This is another location where a juvenile has flown through.

6 I was also able to observe three Bald Eagles, two adults and one juvenile, at the West Sound Wildlife Shelter. DISCUSSION Mike Pratt and the West Sound Wildlife Shelter have reports that there are seventeen confirmed nests currently on Bainbridge Island. I have only been able to locate three, and possibly three different pairs of adult Bald Eagles. I think that this is due to the fact that most of Bainbridge is residential, and there are many locations that I cannot access. The nests that I did locate were spotted after I saw a nearby eagle; I began noticing this in mid- January possibly because winter is the beginning of mating season. Pairs are claiming or reclaiming nests at around this time, and copulation will begin in February here on Bainbridge, according to Pratt. He also noted that eggs are laid in April, and vocalizations have been heard from the nests in late May or early June. This is fairly consistent with the Kaufman s report (1996) that incubation lasts for days. On April 4, 2010 a male was spotted bringing food to a nest, suggesting the eggs had hatched at that point. I speculated that these patterns varied based on climate and food abundance of the year, and Pratt confirmed this. The young eagles will begin to branch out of the nest around late June or early July here on Bainbridge. Pratt noted that they have about fifty days to fledge; after much whining and wimpy behavior (in his words) the parents will eventually encourage the young to fly. Soon

7 after this amazing feat, the new family will set out in early August to rivers where Salmon are spawning. This family vacation does not end like perhaps yours or mine, however. The parents will return to Bainbridge, or wherever their respective homes are, without their young. In fact, according to Pratt, these offspring will never be allowed to return to the nest, since they can often become a threat to the parents and their future offspring (and Bald Eagles mate every year). As the winter months are continuing, I am excited to see the mating process begin. There have already been reports from Bainbridge locals that courtship has begun, identified by miraculous displays in flight by the pair at Fay Bainbridge. This is the easiest pair to observe, since their nest is close to the water and very observable. Bald Eagles are very sensitive to human impact, according to Savage (1987), and a major cause for a lot of eagle deaths were toxins ingested secondhand from sea life. Savage (1987) also notes that these eagles are not fond of human interference, and will even avoid hunting if people are in the area. Despite the large population of people here on Bainbridge, I think the habitat is relatively hospitable. The eagles take year-round residency here, and seem to have a steady supply of food. It makes me wonder, though, how drastically the population of eagles has dropped since an increase in housing developments here: is there a significant difference? I am also curious to know where Bald Eagles find their materials for nest-building; since they are

8 often in trees that seem stripped of branches towards the top, I wonder if the eagles are responsible for this? Bald Eagles, the national symbol of the United States of America, have been through ups and downs in population size. Hunted, poisoned, and stripped of homes have been low points in their history. They are, however, making their comeback as a regal and persevering species. Here on Bainbridge Island we have the pleasure of living side by side with these fine neighbors.

9 Works Cited Wheeler, B. K. (2003). Raptors of Western North America. Princeton, NJ: Princeton University Press. Feduccia, A. (1996). The Origin and Evlolution of Birds (Second Edition ed.). New Haven, CT: Yale University Press. Gordon, D. G. (1991). The Audubon Society: Field Guide to the Bald Eagle. Seattle, WA: Sasquatch Books. Kaufman, K. (1996). Lives of North American Birds. New York: Houghton Mifflin Company. National Audubon Society. (1994). Field Guide to Birds: Western Region. New York: Alfred A. Knopf, Inc. Savage, C. (1987). Eagles of North America. Ashland, WI: North Word Inc.