Blog #448 Not All Make It!
Not all the offspring in an Osprey colony survive—it’s a sad fact, but a necessary one. Darwin’s survival of the fittest still holds true. Predation from bald eagles and great horned owls cull the less guarded nests of chicks. Foul weather can kill susceptible nestlings if the vulnerable chicks catch a chill. Inclement weather can prevent males from fishing, causing their offspring to starve. Fortunately, the Finger Lakes provide ample fish to feed their Osprey families making this less of a worry. We did lose the hatchlings in one of the Cornell Research ponds nests last month, but, overall, our nests thrive.
Osprey nests in the Barnegat Light colony in NJ, by contrast, suffered a number of losses due to volatile coastal weather. The youngest of Duke and Daisy’s nestlings died from starvation after thriving for 18 days. Cool temperatures and strong northeast winds churned the coastal waters, making it extremely difficult for male Ospreys to hunt fish. The Barnegat Ospreys’ main prey, Atlantic menhaden and summer flounder are difficult to catch at this time of year. The menhaden swim in the open ocean, and the summer flounders rest in the back bays, where wind driven waves make them nearly impossible to catch.
Winds also harmed Osprey nests further south. A four-week-old chick from a nest of four was lost at the Forsythe NWR, and two of three hatchlings died at Cape May Meadows. No doubt more nests were impacted.
Refuge managers feared that continued windy conditions would take more nestlings. Sadly, more tragedy would find the Barnegat Light nest. The second oldest nestling died a day later, also from starvation. And three strikes later, Duke, Daisy’s 17-year-old mate, was missing after a storm, leaving Daisy the sole provider. Only time will tell if Duke will return; he has a history of disappearing after storms. The 24-day-old chick hides when Daisy departs to fish. A nest camera shows Daisy and her chick are thriving. Yesterday, she brought two menhaden to her offspring.
Brood reduction, a common breeding strategy in raptors, eliminates the weakest nestlings to adjust the number of young in the nest to a maintainable level due to changing environmental factors. The youngest perish from starvation brought on by their inability to compete with their siblings to obtain food, is acute during periods of food limitation but not always.
Another form of Osprey brood reduction is siblicide. Asynchronous hatching sets up a size and developmental hierarchy among the chicks, with the oldest chicks most often dominating the younger chicks. Without interference from the parents, the strongest chick pecks their younger nestling(s) to death to survive. Siblicide ensures that limited resources are given to the strongest offspring with the greatest chance of survival. There are numerous videos available on YouTube showing Osprey sibling rivalry and siblicide. Watching these behaviors on a nest camera can be very difficult as the images tug at our heart strings. As you watch, keep in mind that death is integral to the continuation of life, it is the way of nature. And the surviving chick will be tough as nails.
Winds also harmed Osprey nests further south. A four-week-old chick from a nest of four was lost at the Forsythe NWR, and two of three hatchlings died at Cape May Meadows. No doubt more nests were impacted.
Refuge managers feared that continued windy conditions would take more nestlings. Sadly, more tragedy would find the Barnegat Light nest. The second oldest nestling died a day later, also from starvation. And three strikes later, Duke, Daisy’s 17-year-old mate, was missing after a storm, leaving Daisy the sole provider. Only time will tell if Duke will return; he has a history of disappearing after storms. The 24-day-old chick hides when Daisy departs to fish. A nest camera shows Daisy and her chick are thriving. Yesterday, she brought two menhaden to her offspring.
Brood reduction, a common breeding strategy in raptors, eliminates the weakest nestlings to adjust the number of young in the nest to a maintainable level due to changing environmental factors. The youngest perish from starvation brought on by their inability to compete with their siblings to obtain food, is acute during periods of food limitation but not always.
Another form of Osprey brood reduction is siblicide. Asynchronous hatching sets up a size and developmental hierarchy among the chicks, with the oldest chicks most often dominating the younger chicks. Without interference from the parents, the strongest chick pecks their younger nestling(s) to death to survive. Siblicide ensures that limited resources are given to the strongest offspring with the greatest chance of survival. There are numerous videos available on YouTube showing Osprey sibling rivalry and siblicide. Watching these behaviors on a nest camera can be very difficult as the images tug at our heart strings. As you watch, keep in mind that death is integral to the continuation of life, it is the way of nature. And the surviving chick will be tough as nails.
Screen shot of Daisy, with her live chick and two dead offspring, courtesy of Conserve Wildlife Fd. NJ.
Winds also harmed Osprey nests further south. A four-week-old chick from a nest of four was lost at the Forsythe NWR, and two of three hatchlings died at Cape May Meadows. No doubt more nests were impacted.
Refuge managers feared that continued windy conditions would take more nestlings. Sadly, more tragedy would find the Barnegat Light nest. The second oldest nestling died a day later, also from starvation. And three strikes later, Duke, Daisy’s 17-year-old mate, was missing after a storm, leaving Daisy the sole provider. Only time will tell if Duke will return; he has a history of disappearing after storms. The 24-day-old chick hides when Daisy departs to fish. A nest camera shows Daisy and her chick are thriving. Yesterday, she brought two menhaden to her offspring.
Daisy and her remaining chick, courtesy of Conserve Wildlife Foundation NJ.
After the winds leave, the colony will reach a new equilibrium of parents and offspring. Nests left with weaken nestlings will either rally or undergo brood reduction through starvation or siblicide.
Brood reduction, a common breeding strategy in raptors, eliminates the weakest nestlings to adjust the number of young in the nest to a maintainable level due to changing environmental factors. The youngest perish from starvation brought on by their inability to compete with their siblings to obtain food, is acute during periods of food limitation but not always.
Another form of Osprey brood reduction is siblicide. Asynchronous hatching sets up a size and developmental hierarchy among the chicks, with the oldest chicks most often dominating the younger chicks. Without interference from the parents, the strongest chick pecks their younger nestling(s) to death to survive. Siblicide ensures that limited resources are given to the strongest offspring with the greatest chance of survival. There are numerous videos available on YouTube showing Osprey sibling rivalry and siblicide. Watching these behaviors on a nest camera can be very difficult as the images tug at our heart strings. As you watch, keep in mind that death is integral to the continuation of life, it is the way of nature. And the surviving chick will be tough as nails.
Not all the offspring in an Osprey colony survive—it’s a sad fact, but a necessary one. Darwin’s survival of the fittest still holds true. Predation from bald eagles and great horned owls cull the less guarded nests of chicks. Foul weather can kill susceptible nestlings if the vulnerable chicks catch a chill. Inclement weather can prevent males from fishing, causing their offspring to starve. Fortunately, the Finger Lakes provide ample fish to feed their Osprey families making this less of a worry. We did lose the hatchlings in one of the Cornell Research ponds nests last month, but, overall, our nests thrive.
Screen shot of Daisy, with her live chick and two dead offspring, courtesy of Conserve Wildlife Fd. NJ.
Osprey nests in the Barnegat Light colony in NJ, by contrast, suffered a number of losses due to volatile coastal weather. The youngest of Duke and Daisy’s nestlings died from starvation after thriving for 18 days. Cool temperatures and strong northeast winds churned the coastal waters, making it extremely difficult for male Ospreys to hunt fish. The Barnegat Ospreys’ main prey, Atlantic menhaden and summer flounder are difficult to catch at this time of year. The menhaden swim in the open ocean, and the summer flounders rest in the back bays, where wind driven waves make them nearly impossible to catch.
Winds also harmed Osprey nests further south. A four-week-old chick from a nest of four was lost at the Forsythe NWR, and two of three hatchlings died at Cape May Meadows. No doubt more nests were impacted.
Refuge managers feared that continued windy conditions would take more nestlings. Sadly, more tragedy would find the Barnegat Light nest. The second oldest nestling died a day later, also from starvation. And three strikes later, Duke, Daisy’s 17-year-old mate, was missing after a storm, leaving Daisy the sole provider. Only time will tell if Duke will return; he has a history of disappearing after storms. The 24-day-old chick hides when Daisy departs to fish. A nest camera shows Daisy and her chick are thriving. Yesterday, she brought two menhaden to her offspring.
Daisy and her remaining chick, courtesy of Conserve Wildlife Foundation NJ.
After the winds leave, the colony will reach a new equilibrium of parents and offspring. Nests left with weaken nestlings will either rally or undergo brood reduction through starvation or siblicide.
Brood reduction, a common breeding strategy in raptors, eliminates the weakest nestlings to adjust the number of young in the nest to a maintainable level due to changing environmental factors. The youngest perish from starvation brought on by their inability to compete with their siblings to obtain food, is acute during periods of food limitation but not always.
Another form of Osprey brood reduction is siblicide. Asynchronous hatching sets up a size and developmental hierarchy among the chicks, with the oldest chicks most often dominating the younger chicks. Without interference from the parents, the strongest chick pecks their younger nestling(s) to death to survive. Siblicide ensures that limited resources are given to the strongest offspring with the greatest chance of survival. There are numerous videos available on YouTube showing Osprey sibling rivalry and siblicide. Watching these behaviors on a nest camera can be very difficult as the images tug at our heart strings. As you watch, keep in mind that death is integral to the continuation of life, it is the way of nature. And the surviving chick will be tough as nails.
Eyes to the sky!
Candace
Candace E. Cornell
Friends of Salt Point, Lansing, NY
Cayuga Lake Osprey Network
cec222@gmail.com
EYES TO THE SKY!
WATCH!
Salt Point Osprey Nest Cam 2022 & 2023
READ!
On Osprey Time: Ospreys of the Fingerlakes
VISIT!
Cayuga Lake Osprey Trail 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, flies in circles, or dives at you, back away Immediately.
•Carry binoculars to view wildlife from afar.
•Help keep local waters clean, healthy, and safe.
•Recycle used fishing lines, twine, and nets, which can kill Osprey.
•Join the Cayuga Osprey Network and volunteer to help monitor Osprey nests: cec222@gmail.com.
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