Observation of Aerial Aggression involving a Bald Eagle (Haliaeetus leucocephalus) and a Turkey Vulture (Carthartes aura).
March 7, 2025
Suffolk County New York
This author observed a Bald Eagle demonstrating aerial aggression, territorial defense or assertion of dominance over the Turkey Vulture during an early morning late winter walk in north central Suffolk County on March 7, 2025. The observations below were made along the Brookhaven Town Rail Trail (or North Shore Rail Trail) a ten mile (10.4 miles, 16.7 km) multi use recreation path that courses through a brushy and wooded corridor and follows the old Wading River Branch Long Island Rail Road right-of-way.
The day began with clear skies and seasonal temperatures of about 40o F and with winds out of NW that were reported locally as 10-15 mph with higher gusts.
Both the Bald Eagle and the Turkey Vulture have become relatively common over the last several years. As a native of Long Island, NY I can attest to the fact up to about a decade ago Bald Eagles were very rare sights, if seen at all. The Turkey Vulture was also a rare mostly summer visitor. But recently these large scavenger birds are more common, and are now observed in winter as well.
There is a well established colony of TurkeyVultures and Black Vultures (Coragyps stratus) in Riverhead, NY. There, a densely developed business and commercial district where in recent decades clusters of ‘big box” retail stores, fast food establishments and hundreds of acres of asphalt surfaced parking lot, have been built and create both wider more consistent source of food, from waste disposal practices and rodent pests, and suitable atmospheric conditions (unstable air generating thermal currents that form over effectively heated roads, parking lots and heated buildings ) that favor the these large birds. The urban generated thermals (from asphalt coated rooftops and heated buildings) persist even in winter months. Then too the surrounding woodlands and agricultural areas provide roosting, foraging and nesting sites. C.atratus is often claimed to be extending its range due to “ human generated global warming” but “anthropogenic urbanization”, more roads, heated buildings traffic, and more waste food may be a much greater factor.
On March 7, 2025, walking west on the Rail Path I observed a Turkey Vulture flying about 150 feet above the Rail Path about a quarter mile away. This vulture with its red head, brown or pale wing undersides, and relatively long wide tail may have been one I observed earlier in the winter, roosting on a tall tree in the vicinity. (The Long Island Lighting Company electric pylons which are sited along this former railroad corridor have a height of about 118 feet and provide a means of estimating heights as well as distances since they are emplaced at intervals of about 100 meter (328 feet) apart.)
The Turkey Vulture taking advantage of a faint updraft and flying in its typical “vulture” circling pattern, slowly gained altitude above the pylons. I continued to observe it, as it rose higher and completed several graceful circles. The large bird with wings held in a ‘v” dihedral rocked back and forth as it responded to gusty winds.
While observing the vulture’s flight just to the west of me, I became aware of another large raptor coming into my peripheral view. This bird seem to have come from a wooded parcel with tall trees located behind me. This bird flew directly and seeming purposely toward the Turkey Vulture keeping to a low level below the top of the pylons. As it passed near my location, I could clearly see the white head and tail of a mature Bald Eagle. It continued to fly toward its quarry, then, as it approached closely, it rose directly below the spiraling vulture and began to fly in a wide circle below the vulture.
The vulture perhaps aware of its continued to gain altitude, to a point well above the pylons. The eagle shortened the radius of its circular path, apparently rising on the same current as the vulture, and flew in smaller circles around the vulture as they both rose higher.
The steady NW wind began to drift both birds to the southeast causing the circling pair to pass nearly directly above me. At this point the vulture, still well above the apex raptor, took advantage of the NW wind, set its wings and flew out of its circular pattern to begin a long downwind glide to the SE. The Bald Eagle followed.
I watched as the vulture flew off with the eagle in what seemed determined pursuit until both birds, the vulture ahead and the eagle in pursuit were well out of sight.
Though we often think of the Bald Eagle as a “fish hawk”, it often eats carrion too and will aggressive take over a carcass from the less aggressive Turkey Vultures. Turkey Vultures have an excellent sense of smell and can located well carrion before it is observed by other scavengers. For this reason other scavenger birds such as the Black Vulture will fly above Turkey Vultures and when they descend onto a road kill site—they have detected by scent the Black Vultures will follow.
Eagles are bigger than any other raptor in its range and will exert its dominance aggressively.
This observation between Turkey Vulture and Bald Eagle appears to be an example of aerial aggression and harassment of a turkey vulture by the apex scavenger in the area to assert dominance over a particular feeding or roosting area.
Bald Eagles will steal food as well, or seem too. On another recent occasion I observed an Osprey (Pandion haliaetus) flying over near-by Mt Sinai Harbor, with a herring or bunker in its talons. A Bald Eagle swooped down on the osprey in an apparent attempt to force it to release its prey. But the smaller osprey flew in such a way to avoid the aerial attack, still holding on to the prey. But a second more determined attack from above by the larger bird caused the fish hawk to drop the small fish which splashed into the bay. The Osprey flew off. The eagle made no attempt to retrieve the fish—which was clearly visible on the surface and simply flew off in another direction. The effort was perhaps simply to establish dominance and indicate “don’t fish here, this is my area”.
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