Eagle egg hatch in jeopardy: expert
Last Updated Tue, 02 May 2006 16:10:58 EDT
The remaining egg in a British Columbia eagles nest is at a critical period if a healthy eaglet is to be born, an expert says.
Millions of internet viewers have flocked to a website streaming live video from a webcam focused on the Hornby Island nest.
Retired accountant Doug Carrick set up the camera, which has been trained on a pair of eagles standing watch over two eggs. One of the eggs has since vanished.
While the remaining egg appears to be in the hatching process, or pipping, Brian Keating said there may be a problem.
"It's been pipping for a long time," said Keating, the head of conservation outreach at the Calgary Zoo.
If the pipping stage isn't completed within 48 hours or less, the inside of the shell could dry out, preventing the chick from rotating. The chick could also become stuck to drying blood inside the shell.
"That chick may be glued inside its egg, can't move, can't get out," Keating said. The mother eagle, he said, won't intervene to assist the chick.
"The mother eagle will let the baby eagle accomplish that on its own," Keating said. "It's a very strenuous, very difficult period of time for the baby chick."
Eagle chicks develop a specialized pipping tooth – a knob on the beak that falls off after it's hatched. They also have a very fat pipping muscle in their neck to help them crack through the membrane and shell, Keating said.
"If [it's] malplaced, that can be a problem," he said.
Missing egg's location unknown
Keating said while the webcam video is inconclusive, there are a number of possible explanations for the missing egg.
"Maybe the egg is buried in the nest, or it was pushed out and taken by some kind of nocturnal predator," he said.
Ravens may have swooped in and snatched it if the eagles were briefly scared away from their nest.
"I've actually seen ravens carrying duck eggs away from a duck nest," Keating said, "so ravens are completely capable of picking up that egg."
Eagles will come to the eventual conclusion that the egg won't hatch if it remains intact well beyond the 35-day incubation period.
Carrick, 73, received federal and provincial government approval to set up the webcam while the eagles were on their annual migration. Located 40 metres up in his neighbour's tree, the webcam is attached to a video cable that runs to Carrick's television.
His website has been receiving more than three million hits a day from visitors around the world.