BLOG #377 Osprey Breeding Timeline

 Ursula and Orpheus of Salt Point flying together, courtesy of Cindy and Karel Sedlacek. 

Ospreys follow a strict breeding schedule, one you can almost set your clock by until, that is, recently.  The arrivals began around April 1, but arrival dates have been creeping forward over the last ten years as  the climate changes. This blog examines a brief timeline of the typical Cayuga Lake Osprey breeding  season. 

NESTING FACTS 


Clutch Size: 

Number of Broods per year: 

Egg Length: 

Egg Width: 

Incubation Period: 

Nestling Period: 

Egg Description: 

Condition at Hatching: 



End of March-Early April 

1–4 eggs 

1 brood 

2.2–2.7 in (5.5–6.8 cm) 

1.6–2.0 in (4.2–5 cm) 

36–42 days 

50–55 days 

Cream to pinkish cinnamon; wreathed and spotted with reddish brown. Capable of limited motion. Covered with down and with eyes open. 

After overwintering in Central or South America, the male typically begins his migration to his Finger  Lakes breeding ground in March and arrives in the Cayuga Lake basin at the end of March-early April.

Early April  

The female typically arrives about a week after the male. It’s a busy month as the pair works to create a  nest or to build upon a previous nest. As soon as the female arrives breeding begins and three weeks  later the female lays her first egg. 

Ophelia arrives at her nest, courtesy of Cindy and Karel Sedlacek. 

Orpheus scraping an egg cup in the nest while Ursula eats fish.

May 

Ospreys mate frequently for three weeks. Initially it is to get the female’s gonads to ripen her eggs for  breeding, but during the third week these copulations serve to fertilize the eggs.  

Orpheus about to mate with Ursula. 

Orpheus mating with Ursula.

End May–Beginning of June 

When the nest is ready, the female will lay 1–3 eggs. The female primarily incubates the eggs for 36–42  days, but at Salt Point, the male Orpheus is keen on sharing this duty.  

Mother Ospreys and three eggs, courtesy of Okoboji Osprey. 

Summer 

The Osprey chicks will begin to hatch at the end of May or beginning of June. The female will keep the  chicks underneath her wings to keep them warm until they begin to grow feathers. Both parents care for  the chicks—the male provides the food and the mother watches the kids. When the male catches a fish,  he eats the head then brings the rest of the fish to the female and the chicks in the nest. 

Mother and her weeks old offspring, courtesy of Okoboji Osprey.

Late July 

The chicks will match the size of the adults within about 55 days, at which point they will begin to test their  wings. The largest chick usually begins to fly first, followed by the others. They will fly progressively longer  and longer distances to gin expertise. 

Three young and their mother (center), courtesy of Cindy and Karel Sedlacek. 

Three juveniles and their father carrying at stick, courtesy of Cindy and Karel Sedlacek.

August 

Fish represent about 99 percent of osprey diet: the fledges must learn to fish. Their parents do not  explictly teach them to fish; they may learn from watching one another. The adult female usually migrates  to its wintering area a week or so before the young fledge (take flight). 

Male eating a fish at Stewart Park, courtesy of Cindy and Karel Sedlacek. 

September 

The Osprey begin their migration south at about the beginning of September. The male in the Cayuga  Lake Basin leave after the full-grown chicks although there are claims males can depart before the young.  All migrate and overwinter independently. The chicks stay in their overwintering location through 

Female juvenile starting its fall migration, courtesy of Cindy and Karel Sedlacek.

a full calendar year before returning to establish their own nest within approximately a 50-mile radius of  their birth. (See Blog #378 Dispersal.) 

Eyes to the sky! 

Candace 

Candace E. Cornell 

Friends of SaltPoint, Lansing, NY 

Cayuga Lake Osprey Network 

cec222@gmail.com 

  

EYESTOTHESKY! 

WATCH! 

Salt Point Osprey Nest Cam 

READ! 

OnOspreyTime: Ospreys of Salt Point 

VISIT! 

Cayuga Lake Osprey Trail


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