Blog #481 Sunshine at Last!
Meteorologists report this is the 6th day of sun in all of May with more rain in the forecast. This is good for the plants but potentially damaging to the Ospreys. Foul weather rots eggs and makes hunting difficult to impossible at a time when the hatchlings are most vulnerable to the starvation, cold, and predation. Despite the challenges of fishing in windy, rainy conditions, Orpheus succeeded in keeping the family fed by catching small, nearshore fish and making up for deficiencies with large trout whenever there was a break in the weather.
A foggy morning feeding the 2 ½ week-old chicks, Salt Point Osprey Nest Cam.
The 3 week-old chicks in their reptilian phase, courtesy of YouTube.
Oakley, the eldest chick, just turned two-weeks old and is passing into the Reptilian Phase, where the now darker, scaly chicks. In this transitional phase Oakley’s buff down is quickly replaced with a dense, dark, wooly down, which will last another two weeks. While in the Reptilian Phase the chicks resemble prehistoric raptors with enormous beaks, oversized bluish-grey feet, and long, black talons. Eleven day-old Ori is still covered with the camouflaging striped gray and buff-colored down, while Oney is darkening and moving into the Reptilian Phase as well.
An artist’s vision of feathered Bambiraptor, courtesy of Wiki Fossil.
With their prehistoric-looking deep orange eyes, enormous beaks, and protruding pin feathers, these young birds instinctively crouch at danger akin to the ancient theropods from the Cretaceous period 65 million years ago. Of the dinosaurs in the Cretaceous Era, the Dromaeosaurs—the birds—survived. The Bambiraptor, a ground-dwelling, feathered Dromaeosaur with hollow bones and a skeleton almost identical to that of the modern roadrunner, shares many traits with modern birds. Bambiraptors were two-feet long, weighed five pounds, and were vicious hunters of other dinosaurs. Bambiraptors, residing on the lineage leading to modern birds, could not fly because their arms were too short to function as wings.
The three Salt Point nestlings are feeding well and growing like rapidly. Instead of having teeth to grind food, Ospreys digest their food using a two-part stomach. The first chamber is known as the crop, an enlarged sac-like section of the esophagus, where saliva-like chemicals begin to break down the food. The partially digested food is moved to the second chamber called the gizzard. Here the food is ground using sand and grain ingested by the bird and stored until digestion can be completed. As the young become satiated on fish, their crops are noticeably distended with food.
Salt Point’s siblings are imprinting and forming critical attachments with their parents and learning to be Ospreys. Ursula has taught them to lay flat and remain still the instant she gives a sharp warning—a harsh Cheerp! The chicks rely on camouflage to keep them safe in the nest. When seen from above by aerial predators such as bald eagles and crows, the chicks blend in thanks to their dark sides and light stripe down the back making them look like sticks in an empty nest.
All three little ones are becoming mobile and able to back up to the nest rim to squirt feces over the nest although they sometimes miss. At feedings, the ball of sleeping chicks perks up with the eldest, Oakley, pushing his way to Ursula. Initially, Oakley and sometimes Oney, dominate feedings, but once satiated, the other siblings are fed. Their enlarged crops tell show their needs are being satisfied.
At ten days old, the chicks begin a rapid growth spurt, which accelerates around day 20 (see graph below). From day 30 to roughly day 33, a maximum growth rate transforms their appearance and size daily. By day 35, the males plateau while the females continue to grow, eventually becoming about 25% larger than the males. This growth pattern is common in most raptors and results in sexual dimorphism in Ospreys. Females need to be larger to defend the nest, but the males must remain sleek, fast, and agile to be successful hunters.
Mother feeding reptilian phase chick, courtesy of Dify Osprey Project.
The breeding season is a great race against time for all: the sooner the Osprey chicks grow and fledge the nest, the more time they will have to refine their flying and fishing, essential life skills they must master before their long migrations in September.
Eyes to the sky!
Candace
Candace E. Cornell
Salt Point Natural Area
Cayuga Lake Osprey Network
Eyes on Ospreys!
WATCH!
Salt Point Osprey Cam 2025 LIVE! authenticated
Salt Point Osprey Nest Cam 2019-24
READ!
VISIT!
Complete Cayuga Lake Osprey Trail
Cayuga Lake Osprey Trail Nests Driving Tour
PROTECT:
• Stay 100-300 feet away, back off if bird vocalizes immediately!
from Osprey nests during the breeding season.
• Always carry binoculars to view wildlife from afar and use you car for a blind.
• Collect and dispose of used fishing lines, twine, nets, and plastics
which can kill Ospreys and other animals of the lakeshore
FIND A BABY OR INJURED ANIMAL?
Call the Swanson Center at 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.
Please donate to keep these doors open.
Comments
Post a Comment