Blog #475 The Critical Post-fledging Period

 

O’Leary takes off from his favorite perch, courtesy of Cindy Sedlacek.

Like going to school for the first time, the fledgling youngsters from Salt Point are being exposed to a whole new world beyond the nest. The 30-40-day post-fledging period, which runs from fledging until each bird migrates, is spent honing the life skills necessary for survival. First migrations are journeys of unknowns, hunger, and hazards that test the fledgling’s will and ability to survive. It is vital that each young bird starts her migration in the best physical and behavioral condition possible. Laying down enough fuel in the form of fat is essential for a sucesful migration. Departing on migration underweight and in poor condition is usually fatal.

Newly fledged Ospreys exhibit only modest control as they beat their wings continuously to stay in flight. Gaining altitude can be as problematic as steering. The youngsters stay close to the nest for their first week before venturing farther. As their confidence grows, so does their range.

An awkward landing on a dead branch, courtesy of Cindy Sedlacek.

By interspersing gliding flight with strong wing beats, the young birds can travel farther and faster up and down the lake. Their flights away from the nest can last several hours, but the fledglings usually return at mealtimes. Repeated exploratory flights around the region enable the young birds to create detailed mental maps of their natal territory, which they will follow on their spring migrations two years hence.

Orpheus will continue providing meals for his fledglings to keep them in good condition for their migrations. Like most fathers, Orpheus feeds his young at approximately the same amount as before fledging. If the young need more nutrition than Orpheus can supply, Ursula makes up the slack, leaving whole or partially consumed fish in the nest for the young to share. Other than that, Ursula concentrates on conditioning and gaining weight in preparation for her impending migration.

O’Connor Goes Fishing, courtesy of Cindy Sedlacek

No luck. O’Connor will try again, courtesy of Cindy Sedlacek.

While waiting for a meal at the nest, the young often rearrange the nest interiors, pulling out twigs and poking them inside elsewhere. Developing the dexterity necessary to manipulate sticks with the beak and talons is another life skill essential for survival and reproduction. However, the efforts of the young don’t contribute to nest maintenance.

Fishing is innate in Ospreys. Some researchers claim the parent bird teaches the young, but most disagree. However, fledglings from nests on or near the water have a distict advantage of beinging able to practice fishing more often. Fledglings living close to the water, such as the Salt Point brood, have been seen diving at just four days out of the nest. Frequently they fly along the water dragging their feet toi clean them after eating and probably because it is fun. They often pretend to hunt by grabbing and manipulating floating clumps of moss, algae, and twigs. Fishing practice rarely results in a fish but it provides vital learning opportunities. Fledgings from nests a mile or more away from the water get a later start on practicing dives. Even if a fledgling is sucessful at catching it’s own food, it will report to the nest at mealtime to solicit fish. One US study found some fledglings made their first sucessful dives at 11 days and all had suceeded catching a fish by 20 days after leaving nest.

Eyes to the sky!

Candace

Candace E. Cornell

Friends of Salt Point, Lansing, NY

Cayuga Lake Osprey Network

cec222@gmail.com

O’Shea looking for fish in the water, courtesy of Cindy Sedlacek.

Guest photographer:

Ithaca’s Cindy Sedlacek brilliantly depicts the Ospreys of Cayuga Lake with the intimacy of a true bird lover. Enamored by the animal’s gorgeous wings and graceful flight, her work is a tribute to the power and grace of these stunning raptors.

EYES ON OSPREYS

WATCH!

Salt Point Osprey Cam 2024 LIVE!

Salt Point Osprey Nest Cam 2019-23

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 300 feet away from nests during the breeding season. 

If the Osprey vocalizes, you are too close! BACK OFF IMMEDIATELY.

•Carry binoculars to view wildlife from afar.

•Recycle used fishing lines, twine, and nets, which can kill Osprey.

•Join the Cayuga Osprey Network: cec222@gmail.com.

•Help keep local waters clean, healthy, and safe. Pick up trash and do not litter. Trash stays in the ecosystem a long time before it disintegrates. Plastic just breaks down into smaller pieces.

• If you find an injured animal, that needs care call Swanson Wildlife Health Center

 (607) 253-3060 

The Janet L. Swanson Wildlife Health Center, an annex of the Cornell University Hospital for Animals, is a veterinary hospital dedicated solely to the treatment of ill or injured native wild animals. They provide expert medical and surgical care for over 1,000 patients annually, from locally and across the state of New York, with the goal of releasing them back to the wild. The Wildlife Health Center operates within Cornell University, a registered nonprofit, and relies largely on public donations.