August 18, 2024
In recent weeks I have observed a pair of Osprey (Pandion haliaetus ) nesting at the top of a 36 meter (118 ft) steel, single-pole electric transmission pylon just west of Peachtree Lane at: 40. 56. 21 N, 73.00.35 W in Brookhaven, Township, near the village of Mount Sinai, on Long Island in New York’s Suffolk County. The pylon nest site is well away from surface bodies of water such as ponds, marshes or the marine environment. Long Island Sound is about 2 miles (3.2 km) from the nest. The only significant fresh water ponds are located in a golf club about two mies from the nest site. The Peach Tree Road nest site is about 2 miles due south of the Long Island Sound shore, and two miles (3.2 km) from Mount Sinai Harbor. It is also about four (4) miles from Port Jefferson Harbor which is located to the northwest.
The question this author asked was where were these inveterate piscivorous “fish hawks’ exploiting fish upon which they depend for 99% of their diet? Or were they exploiting in part the small mammals such as woodchucks, marmots, field mice and cotton tailed rabbits which were all very common along the transmission line right-of-way clearings just below their nest? Or have they found adequate source's of fish? How far away did they have to fly to feed? Were they successful?
Several examinations of the area below the 118 foot high nest revealed only fish remains which were dropped or fell from the nest above. This author observed fragments and parts of fish bodies, such as gill covers, fish vertebral bone and ventral fins of small bony fish. The species of these scant piscine remains were not apparent.
How far away from potential fishing sites?
The Peachtree Lane nest site is located on the North Shore of Long Island about 1.8 miles from the center of Mount Sinai Harbor, a body of water of about 500 acres in area which is confluent with Long Island Sound about two miles (2 miles 3.2 km) to the northwest of the nest site. There are two active Osprey nest sites at the Harbor.
Potential Fishing Sites Inland.
A number of fresh water man-made ponds are located to the southeast of the nest site or inland. Twelve of these small ponds ( estimated average size about 360 ft x 170 ft or @ 1.4 acres surface area ) are located within the bounds of the Willow Creek Country Club golf course, situated to the southeast of the nest site. The center of the Club is about two (2) miles south-southeast of the nest site. The farthest pond in this group is 1.6 miles distant while the closest is about 4,200 ft ( 0.79 miles) from the nest site. The largest pond has an area of 800 x 100 ft (1.8 acres surface area). There may be a total pond surface area in this area of about 16-17 acres at the Willow Creek Club located about two miles (as the crow flies) from the Peach Tree Road pylon nest site
Other than these, a solitary small pond about 1+/- acres in area (also man-made) is located just 3,500 feet (0.7 miles) due south of the nest site.
Two gravel extraction companies are active southeast of the nest site. One of them (with no name) is located just west of Yaphank-Miller Place Road at 2.9 miles distant fro pylon site.
While the Roanoke Gravel and Sand Pit pond is 4.5 miles southeast of the nest site. This body of water has an estimated 113 acres of surface area.
Conclusion:
Though the Peachtree Lane nest site is not situated on the shore of a marine embayment or of a lake, the distance to such bodies of water are relatively short. A number of small fresh water ponds occur at 3.2 km away with about 16-20 acres of total surface area. At the same 2 mile (3.2 km) distance lies the expansive Long Island Sound, which is confluent with shallow water marine bays and harbors with large areas of surface water at similar distances. Thus the nest site seems sited in a location which provides easy access to both fresh or marine exploitation areas for Osprey at almost equal distances away.
The 118 foot high transmission line pylon provides a structurally sound base for a bulky heavy nest and its height and metal surface provides almost absolute security from terrestrial predators. To protect the power lines from damage from growing trees the surroundings are clear cut of trees by the L.I.utility company. This tends to provides unfettered flying space around the nest as well as security from avian predators such as crows and other raptors. Osprey may prioritize the location of a nest sites for its security from predators and its structural soundness over the distance to its fishing sites.
While boating in Mount Sinai Harbor this author observed an osprey flying directly over head carrying a small fish in its talons. I assumed it was one of the two pairs nesting on the shore at the Harbor. The fish hawk appeared to be returning to its nest site with its prey. As it passed over-head, a second large black bird with prominent white head appeared flying close behind the hawk. The American Bald Eagle (Haliaeetus leucocephalus) seemed to make an attempt to force the fish hawk to release its hard won prey (a small fish about the size of a sea perch, cunner or bergall). The osprey twisted and turned in the air, but encumbered with the fish held head-first in its talons, failed to out pace or out-maneuver the larger bird. Finally, perhaps to get away, it dropped the fish into the bay, where it dissapeared below the surface. The eagle swooped down over the location, but abandoned the chase and flew off in one direction, while the osprey flew in another..but with no fish.
Note: On this date the author observed the response of the (assumed male?) Osprey at the Peachtree Lane Nest to the presence of a Red Tailed Hawk (Buteo jamaicensis). The Ospreys ignored the presence of the hawk while it perched on an adjoining pylon about 100 meters (328 feet) away. When the hawk flew off its perch, it passed within a 50 meter radius of the nest, the smaller Osprey, then took off in pursuit. The hawk descended quickly and flew into the forest canopy presumably to escape.
Addendum: On August 29, 2024 I observed the Peachtree Lane nest site again. The nest atop the pylon appeared to be deserted. I searched the grassy area around the base of the pylon where I observed several dried gill covers of what appeared to be clupeiform (herring like) fish and the dried head of what appeared to be a Bunker or Atlantic Menhaden (Brevoortia tyrannus). This seems to confirm that the Osprey were fishing in Long Island Sound or Mount Sinai Harbor about two miles away.
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