Marine Corps Base Quantico -- Marine Corps Base Quantico’s Natural Resources and Environmental Affairs Branch conducted an aerial survey and count of Marine Corps Base Quantico’s bald eagle population from an MV-22 Osprey on Saturday. Ten employees from Natural Resources and Environmental Affairs participated in the endeavor.
John Rohm, head of the Fish and Wildlife and Agronomy Program aboard MCBQ, was in charge of this year’s count. He said NREA began monitoring the eagle population in 1984, and counts have been conducted most years since, though there were no aerial surveys from 2010 through 2012. Rohm said that while eagles are no longer listed as “threatened” under the guidelines of the Endangered Species Act, they are still protected under the Bald and Golden Eagle Protection Act and need to be monitored.
According to the U.S. Fish and Wildlife Service, the primary factors influencing the recovery of the bald eagle population are the banning of the pesticide DDT and the protection of eagle habitats by the Endangered Species Act. The recovery has been dramatic in the coastal Virginia region. The bald eagle conservation and management plan for Marine Corps Base Quantico reveals that there were only approximately 30 breeding pairs of eagles in Virginia in the 1970s; however, there were over 730 pairs in the coast region as of 2011 and 850 statewide. The Chesapeake Bay region offers rich prey resources and high-quality habitat for the eagles.
Kristy Craig, a natural resources specialist at Marine Corps Base Quantico, said last year there were four active bald eagle nests aboard the base, meaning an eagle laid an egg and reared young in the nest. There are additional nests aboard base that were not used. So far this year, three of the nests are in current use, though eagles do not all nest at the exact same time, so it is possible one or more will become active in the coming weeks.
Rohm said that eagles are believed to mate for life and that they practice nest-site fidelity, meaning the same pair will come back to the same nest yearly to lay eggs. Eagle nests are large, heavy structures — some weigh as much as 4,000 pounds — so a pair of eagles will build one and use it for years. A new breeding pair may find an existing unoccupied nest and use that instead of building one.
According to information provided by the Smithsonian National Zoological Park, “Bald eagles have lived up to 48 years in zoos, although their life span in the wild is likely far shorter.”
In light of an eagle strike by an aircraft last year over the Potomac River in the vicinity of the base, Rohm said MCBQ is currently working representatives from West Virginia University, the Great Lakes Cooperative Ecosystem Studies Unit, Virginia Department of Game and Inland Fisheries, and the U.S. Geological Survey to conduct more intensive monitoring. Approximately 10 eagles will be captured, fitted with leg bands and small backpacks containing recording and tracking devices and released. The data collected will reveal the territorial ranges, flight paths and circadian rhythms of the birds residing in the area.
According to the conservation plan, research on the movement of eagles can be used to help identify time periods (daily and seasonally) when the potential for a bird/aircraft strike is high and also to evaluate the need for and effectiveness of nest removal near the airport.
Those on the survey flight Saturday spotted approximately five from the air this year, whereas 25 sightings were made last year.
Rohm does not believe this is a cause for concern, however, and feels the airframe used may have been a factor in the different number of definite sightings. Last year’s aerial survey was conducted in a CH46 helicopter, which has more windows and flies slower than the MV-22, meaning more volunteers had a clearer viewing opportunity. Different environmental factors such as temperature and wind may have also affected the number of birds actively flying around that morning, compared to during last year’s survey.
Base residents are welcome to view the eagles and their nests from a distance. However, under the provisions of the Bald and Golden Eagle Protection Act, it is illegal to “pursue, shoot, shoot at, poison, wound, kill, capture, trap, collect, molest or disturb” an eagle or its nest or eggs. The U.S. Fish and Wildlife Service website states that “A violation of the Act can result in a fine of $100,000 ($200,000 for organizations), imprisonment for one year, or both, for a first offense.”
—Writer: ebaker@quanticosentryonline.com