Blog #461 Sneak Peek at Osprey Season 2024
Ospreys are philopatric—they return to their area of their birth after the spring migration. Second-year males heading north for the first time will return to their natal areas and try to settle nearby. Females also return to their natal area but breed farther from the area to prevent inbreeding.
To maximize enjoyment of watching an Osprey family, learn about their life history and the stages they go through during their breeding season. This is simple as they nest in the open and are large enough to observe from a respectful distance of 300 feet. Find a nest you would like to observe from the Cayuga Lake Osprey Trail and plan to visit it at least once a week to see a new family of Ospreys be born, grow, and thrive. Once the chicks hatch, they mature quickly.
I. Arrival at the Nest
Ursula with her heavy necklace returns to Salt Point, courtesy of Cindy Sedlacek.
Once a pair has claimed or reclaimed their nest, they will be busy fetching sticks and other nesting materials to repair their nest from winter damage. If you see a pair sitting together, note their size. Females are 25% larger than their male mates and sport a brown spotted “necklace” on their chests. The necklace varies from faint and narrow to broad and dark. Adult males have a white breast and sometimes have a faint breast marking as well. As the breeding season progresses, the adult male’s feathers will turn darker from a buildup of waterproofing preen oil he applies daily. By contrast, the adult female’s feathers tend to bleach in the sun after a long season on the nest.
II. Nesting and Courtship
Established pairs use the same nest for life while repairing it every spring. New pairs may take over abandoned nests or start new ones on sturdy substrates. Both mates collect nesting material. The male gets the bulk of branches and heavy sticks while the female collects more delicate mosses and grasses for the egg cup. The male will continue to add to the nest all season. Males have an interesting way of shaping the nest cup. I call it the “snowplow.” The male lies on his belly and kicks nesting material backward toward the nest rim, reminiscent of a snowplow. Osprey nests can grow quite large over years, weighing in excess of 500 lbs.
Courtship begins as soon as the mated pair reunites, or a new pair bond is formed. The definitive way to distinguish male from female is to watch their pair bonding. In successful copulations, the male mounts the female while she pulls her tail to the side and bows her head. Frequent mating during the next 14 days serves to bring the female into breeding condition, raising her reproductive hormones to levels that allow successful breeding. It is only the last few copulations that fertilize the eggs.
When you watch courting Ospreys, you will see more than just repetitious mating. The male must be attentive to his mate and bring her ample fish if she is to breed. The pair will sit side-by-side in the trees, quietly vocalizing or flying together, looping and circling to cement their bond. Many observers view these private interactions as intimate and romantic.
Orpheus shapes the nest using his legs as a “snowplow.”
Osprey pair about to mate, courtesy of Cindy Sedlacek.
Orpheus ate the head of the fish he is giving to Ursula, courtesy of Cindy Sedlacek.
Remarkable Osprey ‘sky dances’ are performed by courting males to entice their mates even further. The male performs his sky dance—an aerial ballet performed with a stick, fish, or empty talons—while his mate sits on the nest. The male flies a few hundred feet up, hovers while calling out, and suddenly drops 50 or so feet. Here he hovers, cries out, and suddenly dips again. He rises and dips until reaching the nest to present his prize to his mate.
III. Egg Laying and Incubation
After a few weeks of courting, the female’s ovaries have matured and are ready to produce eggs. The longer a pair has been mated, the sooner the female will enter breeding condition. Females lay 1–4 eggs, laying one every 1–2 days. Laying usually takes place in the morning. Laying is accompanied and followed by incubation, which is evidenced by adults taking turns sitting low in the nest. Some males offer minimum help with incubating, but Orpheus is very much a hands-on—sorry: talons on—dad. He often pushes Ursula off the nest to get a turn. During incubation, the female often sits low on the nest, making the nest seem deceptively empty from the ground level. The incubation period can last 35–43 days, with the female doing the heavy lifting through sun, wind, rain, and other forms of inclement weather. (Mother Ospreys are the heroes of our story.)
Snow covered female Osprey tending eggs, courtesy of Cindy Sedlacek.
IV. Hatching
Hatchlings leave their shells 35–43 days after incubation begins. For a few days prior to hatching, the embryo and adults communicate with soft peeps through the porous eggshell. Hatching is an arduous process for the tiny chicks as they fight to enter the world. When the nestling is free of its shell—sometimes taking up to a day—it is feathered, and its eyes open. After a few hours, the hatchling dries off and is hungry for fish.
Look for the male bringing food to the nest and making "head bows" into the nest center. The male and female often have a tug-of-war over the fish when he first arrives at the nest and sometimes insists on feeding the youngsters himself. Typically, the female grabs the fish and feeds her chicks one at a time, usually with the loudest one getting fed first.
The fast-growing chicks can usually be seen poking their heads above the nest rim within 2–3 weeks, making mealtime the best time to view them. Chicks feed eagerly and noisily. Hatchlings walk to the rim of the nest to defecate.
Month-old nestlings poking their heads above the nest rim, courtesy of Andy Morfew.
By four weeks, the nestlings are easy to see, when not sleeping in the shade of their mother’s wings. The young birds chirp to welcome their father-carrying fish to the nest. The nestlings have also been taught to lay flat if danger is near.
VI Fledgling
Chicks begin flying when they are 7–8 weeks old and are still fed by the adults until they migrate. The first flights are enjoyable as the young awkwardly perfect their skills and turn into graceful flyers.
Ospreys are our bell-weather of lake health and water quality. If Cayuga Lake’s chemistry became off balance, the Osprey would vanish. These fish eaters are also top predators and central in the lake’s ecosystem.
Eyes to the sky!
Candace
Candace E. Cornell
Friends of Salt Point, Lansing, NY
Cayuga Lake Osprey Network
Guest Photographer:
Musician and Director of Data Administration and Reporting at Cornell University, Cynthia Sedlacek is a rising artistic talent. Cynthia’s affection and admiration for raptors are evident in her exciting photographs Ospreys nesting around Cayuga Lake and the red-tailed hawks of the Cornell Campus. Her photographs of local Ospreys are incomparable as she captures their essence—their inner bird. From the hard-to-see nestlings to the fast-flying adults, Cindy goes catches all aspects of Osprey life in the Cayuga Basin. She and her husband, Karel, are also avid nest monitors for the Cayuga Lake Osprey Network and video stream footage of the campus hawks.
EYES TO THE SKY!
WATCH!
Salt Point Osprey Nest Cam LIVE!
READ!
On Osprey Time: Ospreys of the Finger Lakes
VISIT!
Cayuga Lake Osprey Trail Nests Driving Tour
Complete Cayuga Lake Osprey Trail
HELP PROTECT OSPREYS:
• Stay 100–300 feet away from Osprey nests during the breeding season.
If the birds get overly stressed, they may abandon their nest and eggs.
If the Osprey vocalizes or flies from the nest, you are too close!
BACK AWAY IMMEDIATELY.
• Carry binoculars to view wildlife from afar.
• Help keep local waters clean, healthy, and safe.
• Pick up used fishing line and tackle, twine, nets, and plastic garbage along the shore,
which can kill Ospreys and other animals living along the lake shore.
• Join the Cayuga Osprey Network, and volunteer to help monitor Osprey nests: cec222@gmail.com.
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