Eagle Nesting in Georgia Soars to New Heights

Social Circle, GA
Wednesday, May 3, 2017 - 13:45

 

 

The number of active bald eagle nests in Georgia reached a record high this year, the state Department of Natural Resources announced today.

Statewide aerial surveys detected 218 occupied nest territories. That eclipses the previous record of 210 in 2015 and marks the third straight year that more than 200 active bald eagle nests have been documented in Georgia.

Mirroring a comeback across the species’ range, bald eagles have rebounded in the state from no known nests in 1970 to nests this year in at least 68 counties, according to survey leader Bob Sargent. In the last 10 years, the number of occupied nest territories in Georgia has almost doubled.

“The recovery of the bald eagle in Georgia is a truly inspiring success story. This is a 7-foot-wide soaring example of the effectiveness of the Endangered Species Act,” said Sargent, a program manager with DNR’s Nongame Conservation Section.

At least 142 of this year’s nests were successful, fledging a total of 218 young eagles, an average of 1.5 per successful nest. Four nests appear to have fledged as many as three young. In 2016, 149 of the 201 occupied nesting territories were successful, fledging an estimated 240 eaglets.

The dip in fledgling estimates this year compared to 2016 does not concern Sargent. He explained that adults were still incubating eggs in many southwest Georgia nests during the follow-up flight in March. Since fledging of nestlings from those eggs, although likely, could not be assumed, those numbers were not added to the total.

The Nongame Conservation Section monitors eagle nesting through helicopter surveys in January and again in March and early April. The initial flights are focused on finding all active nests: those with eggs, eaglets, an adult in an incubating posture or evidence that eagles have been prepping the nest for use. The second round of surveys is aimed at determining the reproductive outcome of those nests and checking recently reported new nests.

Factors feeding the national bird’s recovery include a U.S. ban on DDT use in 1972, habitat improvements after enactment of the federal Clean Water and Clean Air acts, protection through the Endangered Species Act, increased public awareness, restoration of local populations through release programs, and forest regrowth.

In 1989, the Southeastern recovery plan set 20 occupied nest territories in Georgia as a goal. “It was an especially low bar in terms of measuring success because the species was in such dire straits here,” Sargent said.

Yet while the recovery of the bald eagle is encouraging, “there continue to be reasons for concern,” he added.

Along Savannah River reservoirs, for example, nest numbers are lower than expected. One reason why is avian vacuolar myelinopathy, often referred to as AVM, a neurological disease deadly to coots and the bald eagles that prey on them. This winter, 10 eagle carcasses were found at Clarks Hill Lake (Strom Thurmond), an AVM hotspot. The cause of death for those eagles that could be necropsied was AVM, Sargent said.

Sargent also reiterated the unexpected downside of an increased eagle population, including more birds being hit by cars as eagles, mostly sub-adults, eat roadkill; incidents of eagles being shot; and, birds suffering lead poisoning after scavenging animal carcasses containing lead shot, bullets or slugs.

The public is encouraged to report eagle nests via www.georgiawildlife.com/bald-eagle, (478) 994-1438) or bob.sargent@dnr.ga.gov. Such reports led to 12 of the 17 new nests this season. (Tip: Osprey nests are sometimes confused with eagles’. If unsure, check out the differences online, including at http://bit.ly/2ptuRtm.)

DNR works with landowners to help protect bald eagle nests on private property. Although de-listed from the Endangered Species Act in 2007, eagles are protected by the Bald and Golden Eagle Protection Act, the Migratory Bird Treaty Act, and state law. In Georgia, the species has a state classification of threatened.

The surveys of these iconic birds are part of the DNR Nongame Conservation Section’s mission to conserve nongame wildlife – native animals not legally hunted or fished for – and native plants and natural habitats.

The resurgence of bald eagles is supported in part by Georgians who buy or renew an eagle or hummingbird wildlife license plate. These tags cost only $25 more than a standard license plate and $19 of each purchase and $20 of each annual renewal goes to help conserve bald eagles and hundreds of other Georgia plant and animal species listed as species of conservation concern.

Learn more at www.georgiawildlife.com/conservation/support. See how that support is put to work www.georgiawildlife.com/conservation/AnnualReport.

SURVEY SUMMARY

  • Occupied eagle nest territories: 218
  • Successful nests: 142
  • Young fledged: 218
  • Counties with active nests: 68
  • Lead nest counties: Chatham, 22; Decatur, 18; Camden¬, 13, McIntosh, 13; Glynn, 11, Liberty, 11


SURVEY INSIGHTS

Round-one Flights: DNR eagle nest surveys consist of two rounds of flights, each taking five days. The first round is called occupancy flights. Flown between the second and fourth week of January, these flights are focused on finding all active nests in the state. An active nest is one with eggs or an adult eagle in an incubating posture, eaglets (rare in Georgia in January), or evidence eagles have been prepping the nest for use. To make the best use of helicopter time, occupancy flights focus on nests used the previous year, reports of possible new sites and examination of areas with a high probability of supporting new nests. Reports by biologists and other residents accounted for 12 of the 17 new nests this year and monitoring of 11 nests from the ground.

Round Two: The second round of flights, from mid-March to early April, is aimed at gauging the reproductive outcome of nests visited in January and visiting reported new nests. By late winter, most nests either have eaglets ranging in age from 4-14 weeks old or they are empty because the nesting effort failed or, in a few instances, the eaglets have fledged.

Nest Timing: DNR survey leader Bob Sargent said there is a marked latitudinal gradient with regards to the timing of the nest cycle. Eagles on the coast nest earlier and fledge young earlier than those in the mid-state, and much earlier than those nesting on the perimeter of mountain reservoirs. And as with all birds, the causes of nest failure vary and can include severe weather, death of one or both parents, insufficient food available to rear young and predation of eggs or young by raccoons, great horned owls and other wildlife.

After Matthew: Sargent was curious to see how coastal nests fared in the wake of Hurricane Matthew. Yet only five nest trees appeared to have fallen because of the October storm, despite swaths of devastated forest on Little Tybee, Ossabaw, Blackbeard and St. Catherines islands. On the flipside, Sargent found five new nests on the coast. About 35 percent of the state’s active nests were found in the six coastal counties.

Pilots Key: By the end of the surveys, Sargent and DNR pilots Maj. Gary “Doc” Watson and Capts. Ed Watkins and Steve Turner had peeked into 293 nests from Walker to Camden counties. Sargent calls the pilots “ornithologists in training” and said their part in the surveys goes beyond flying. “They often find the nests before I do, they are as fascinated by the big birds as I am and they are especially conscientious about keeping a safe distance from the nests – for the eagles’ sake – while giving me the best possible look at the contents.”

Nest Trees: Data collected about the nest trees this survey season show that of 263 current or recent nest trees examined, 251 (95 percent) were pines, mostly loblolly, but also longleaf, white and Virginia pine. Eleven of the remaining 12 trees were cypress, and nine of those were on the coast.

Sargent often gets calls from the public about “eagle nests” in dead trees, especially the very tops of the trees, and on high-voltage towers, cell phone towers and bridge structures. Sargent’s preliminary analysis indicates that only 19 of the 263 nest trees examined were dead or dying, and about five nests were at the very top of the trees. No eagle nests were documented on manmade structures, but many osprey nests were seen on towers, river channel markers and bridges. The latter species often nests in dead trees.

Oddly enough, one tree on Blackbeard Island featured three eagle nests stacked one above the other like apartments; the top one was occupied. On Wassaw Island, Sargent saw a great horned owl incubating eggs in a nest that had been built by eagles, which is not an unusual occurrence.