Bald Eagle Brochure- edu project

Sitka’s Alaska Raptor Center (ARC) The Alaska Raptor Center is a 501 (c)(3) non-profit organization located in Sitka, Alaska. They aim to rehabilitate and release injured raptors from across Southeast Alaska. Some of the birds who are non-releasable become “Raptors-in-Residence”. The facility was first established in 1980 and currently treats between 100 to 200 birds per year. All data was obtained from this facility in a 15-year period.

Figure 1: Bald Eagle Population Counts

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Audubon Christmas Bird Count In 1900, Frank M. Chapman proposed the Christmas Bird Count. Each year this bird census runs from December 14th to January 5th all over North America. The goal is to guide conservation by evaluating the health of bird populations. Thus, it is necessary to obtain population counts. Bald eagle populations of Alaska are observed remaining relatively stable (Figure 1: red marked line). The record high population was recorded in the winter of 2012 with an estimated count of 4,186 individuals (Figure 1).

E-Bird Checklists E-bird, an online birding database was launched in 2002. It allows birders, amateurs and experts to document any species heard or seen by means of an online checklist. These checklists are reviewed by local researchers before being added to the public database. Sightings that seem unusual are evaluated by local-area biologists. This database considers populations of species on a full year basis, rather than just seasonally. Bald eagle populations are observed increasing over the years (Figure 1: blue marked line). In fact, there was a record high of 21,773 individuals in 2015 (Figure 1).

Bald Eagles in

Rehabilitation For more information, check out these references:

www.allaboutbirds.org www.audubon.org www.ebird.org www.alaskaraptor.org www.alaska.fws.gov www.theraptortrust.org

Introduction The American Bald Eagle Foundation staff was interested in looking at bald eagles entering rehabilitation within Southeast Alaska. Interns used a Chi (pronounced kai)-Square Statistical Test of Independence. This determines if 95 percent of all bald eagles in the dataset were expected to enter the facility for one admit reason more often than another. Additionally, a Chi-Square Goodness of Fit Test was used to determine if a high number of bald eagles in rehabilitation was simply the result of larger populations in the area. Determining the likelihood and causes of bald eagles entering rehabilitation centers allows us to suggest preventatives which the public can employ to prevent the fatality of individuals.

American Bald Eagle Foundation113 Haines Hwy, Haines, Alaska 99827

Phone: 907-766-3094www.baldeagles.org

Special thanks to the Alaska Raptor Center who provided the data for this brochure.Information complied by Amanda Cox ©

2016

Preventatives- Contact a rehabilitation center, the US Fish and Wildlife Service or animal control when a bird requires assistance. - Pick up litter to prevent entanglement, ingestion and/or impact injuries. - Utilize safe alternatives to chemicals and poisons. - Decorate windows or close blinds to prevent impact injuries. - Report sick or dead birds:(Alaska: 1-866-527-3358).- Get involved with your local rehabilitation center to learn more.

Definitions of ARC Admit Reasons To prevent skew when analyzing the data in the statistical software program, we categorized eagles into ten various admit reasons. The admit reason “Human Misc” includes eagles suffering from man-made injuries such as; caught in animal traps, fishing nets or gear, and man-made fires. However those admitted because they were shot, electrocuted by power lines, or suffering toxicity from pesticides or chemicals could be considered indirectly injured by humans. The same could be said for those entering due to “impact” injuries; which include car and plane collisions or structure collisions. Individuals categorized into the admit reason “Drowning” were not necessarily brought the facility deceased, but rather eagles that were just too wet to fly. The admit reason “animal” is a shorthand for eagles caught by animals, which also includes eagles that have collided with one another. “FON/FOG” is a shorthand admit reason for fell out of nest or found on ground, which can include adults on the ground who seem unhealthy but with no known causes. The “ill/injury” category includes eagles that have diagnosed illnesses (i.e. avian pox) or injuries (i.e. fractured bones). Finally, “Natural” means the eagle was affected by natural causes; such as old age.

Figure 2: Bald Eagles at ARC

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Bald Eagles at ARC It is observed that bald eagles enter the Alaska Raptor Center in different proportions than might be expected for their population. This means that a large number of bald eagles do not enter rehabilitation simply because there is a higher population of them in the area (Figure 2).

Figure 3: Reasons Bald Eagles enter ARC

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Reasons Bald Eagles Enter ARC

As a result of statistical testing, 95 percent of bald eagles entering ARC are admitted due to illness/injury, impact, or electrocution (Figure 3: blue observed bar vs. red expected bar). Those admitted as a result of unknown causes were omitted from the data set, thus 512 eagles were considered rather than 846 eagles.

Of the individuals analyzed, ARC bald eagles are most commonly admitted due to illness or injury (30.1%), which, is more than statistically expected. The second most common admit reason is impact (24.41%). This is less than statistically expected. The third admit reason is electrocution (20.51%), which is also more than statistically expected.

Awareness

This research has determined that bald eagles in Southeast Alaska seem to be more susceptible to illness and/or injury. Unfortunately, many of the injuries birds suffer from are a direct or indirect result of humans. This explains sustained injuries as well as impact injuries and electrocution. It is important the public be aware that most diseases which affect birds cannot be transmitted to people. However, these birds do require treatment and should be admitted to a rehabilitation center as soon as possible. Bald eagles are extremely large and strong birds, so it is best not to approach them. Thus, it is our responsibility as community members to familiarize ourselves with rehabilitation centers in our area.

Preventatives suggested by the American Bald Eagle Foundation are located on the back of this

brochure.