Blog #314 What is going on in the nest?

What is going on in the nest? You can’t see from the ground.  What goes on in the nest during incubation? In short, not much. Ophelia spends her  days tending her eggs and keeping them safe. Orpheus spells her so that she can  stretch and eat her fish in a nearby tree. From the moment Ophelia wakes up until the  end of day, she sits and watches the goings on around the nest. She pays little attention  to the people and their dogs walking below the nest, but rather concentrates on the air  space above. She has made peace with the noisy house sparrow nesting in the bottom  of the Osprey nest. This is a commensal relationship, where the smaller bird gets a safe  home, but the Osprey receives nothing for the favor.  

Ophelia is aware of every crow, blue jay, and blackbird that flies by the nest as they  may steal her eggs. But it is the big, dark birds she is really searching for. Vultures,  although no threat to the family, put Ophelia on high alert. Aggressive red-tailed hawks  get a rude welcome at the nest, although they do not harm the fish hawks. Great-blue  herons are pests at the nest although they pose no danger. As long as there is a  predator guard to prevent climbers, the only real threats to the nest are great-horned  owls by night and bald eagles in the day. 

Siting Osprey nests in the open away from tall trees is essential for the family’s success.  Great-horned owls, nesting in the largest of trees, sleep during the day and hunt by  night. Great-horned owl chicks have voracious appetites, and the parents must satisfy 

them. The owls fly silently and easily pick off Osprey nestlings as they lay huddling in  the nest. They also grab an occasional incubating adult off the nest even though they  have comparable weights. These pounce-and-grab predators are incredibly efficient,  leaving only a few feathers in the aftermath of their attack. 

A bald eagle harassing an osprey to get the fish it is carrying, courtesy of Pinterest. 

Eagles, on the other hand, are both predators and pests to the Osprey. During the day,  eagles are kleptoparasites, harassing and stealing the Osprey’s hard-earned fish. If an  eagle repeatedly singles out a particular Osprey, the latter can become frustrated and  give up fishing for the day. (Gulls en masse will also harass Ospreys until they drop  their fish.) Omnivorous eagles will also take advantage of an unguarded nest by stealing  the fledglings.

Ophelia hunkered down and looking around. 

Another enemy of the Osprey is the ubiquitous mosquito. Night vision cameras are  valuable for watching Ospreys having restless nights, surrounded by a cloud of  mosquitos and constantly bitten as they doze. These bites can transmit deadly West  Nile Virus and other mosquito-borne diseases. An Osprey was captured at Myers Point  three years ago, which died of the virus. 

Ophelia’s waking hours are usually spent keeping a 360 degree view of the nest and  searching for the arrival of Orpheus and the presence of intruders and other unwanted  visitors. Her head is constantly scanning the skies. Like an itch needing a scratch,  nesting materials are constantly gathered and rearranged in the nest. Orpheus  continues to bring sticks to weave in the nest and piles of grass, mosses, and aquatic  weeds to protect the eggs. Orpheus and Ophelia repeatedly often stare intently at their  eggs, prompting some to refer to “admiration”. They roll the eggs and keep them  covered with protective grasses. The adults warm the eggs by directly transferring heat  from their bodies to the eggs. As the spring weather warms, the eggs have to be kept at  a constant 99 °F for approximately 32 days. Warm air and normal precipitation are  crucial during incubation. If there are periods of extended rain and low temperatures,  then the egg failure rates and young chick fatalities rise.

Ophelia rearranging a leaf in the nest. 

Incubating Ospreys can be sensitive to disturbance during the critical incubation period.  If they must leave the nest unguarded, the eggs are vulnerable to the sun’s radiation,  cool air, and predators—raccoons, snake, crows, jays, squirrels, etc. Ophelia incubates  through the night and about 70% during the day. Right now, the nests around the lake  look empty as the females lay low in their nests incubating. It’s only when you see them  roll the eggs or preen that their heads protrude above the stick nests. But like Ophelia,  these females are vigilent, protecting their eggs against April’s freezing temperatures,  showers, snow, and egg-cracking hail. 

Eyes to the sky!  

Candace 

Candace E. Cornell  

Friends of Salt Point & 

Cayuga Osprey Network  

Lansing, NY  

cec222@gmail.com

HELP PROTECT OSPREYS: 

• Keep a distance (100-300 feet) from active nests in the breeding season. If an  animal vocalizes when you are near, you are too close! BACK OFF IMMEDIATELY. • Carry binoculars to view wildlife from a distance. 

• Help keep local waters clean and healthy. Preserve and clean shorelines. • Recycle or dispose of used fishing line and other materials that can entangle  Ospreys and other aquatic animals. 

• Volunteer to monitor Osprey nests with the Cayuga Osprey Network. Write to:  cec222@gmail.com.  

EYES ON OSPREYS 

WATCH! 

Salt Point Osprey Nest Cam 2021 

READ! 

On Osprey Time—a blog on the Ospreys of Salt Point 

VISIT! 

Cayuga Lake Osprey Trail