Wednesday, April 02, 2014

Big Jump at Eaglecrest

The Big Jump happened at Eaglecrest on April 1 at 4:42PM PDT, although it didn't go quite as expected. We believe that Wilma laid seven eggs of her own and incubated four additional eggs laid by Trudy, the intruder goose. Six goslings hatched. Of those six, four jumped at roughly 24 hours and two were unable to rise to their feet. All four that jumped made it safely to the pond.

Canada goslings are precoccial birds. They require very little direct parental care or feeding following hatch. Their parents will protect them from predators and other geese and help them find food, but they don't incubate the young after hatch or bring food to them in the nest. Canada goslings need to be able to get on their feet quickly, since the entire family leaves the nest roughly 24 hours after hatch starts.

The goslings that didn't jump were never able to get to their feet or move significantly from one place, which indicates they experienced some kind of damage during development in the egg. One of the goslings had already completely dried off, indicating hatching had happened some time ago. The other, while still wet, was unable to get up or propel itself at all. Canada goose hatchlings should be able to come to their feet very quickly once hatched. That those two didn't indicated something was wrong.

So why did two of the embryos fail to develop properly? We don’t know for sure. The eggs could have been injured in the struggles between Wilma and Trudy or damaged because Wilma couldn’t incubate, turn, or aerate all eleven eggs properly. From our point of view, two goslings died without reaching their feet and one egg failed to hatch. But from the goosey point of view, four goslings survived to fledge. Would waiting another twelve to twenty hours have saved the two goslings that failed to rise? No, but it might have harmed the successful hatchlings, who needed nourishment they couldn't get in the nest. Fred and Wilma gave their healthy, living offspring an excellent chance at survival by jumping when they did.

Some video of the goslings from Eaglecrest:

New goslings – MsDebbiB: http://youtu.be/DAp15Xu_rm8
Gosling leg stretch – Eaglewhisperer18: http://youtu.be/QsOIW3VKG2g
Wilma’s little goslings – Mocha Mama: http://youtu.be/uxnIZVrAzGU
The Jump! – Mocha Mama: http://youtu.be/sUHSmVge3-0
Waddle to the pond – Mocha Mama: http://youtu.be/C91I5Pl_pqA
Goslings swim - MsDebbiB: http://youtu.be/LijKt2jfczc

To learn more about incubation and heat/cold damage, follow this link:
http://www.brinsea.com/customerservice/poweroff.html

To learn more about the differences between altricial and precoccial birds, click here:
http://goo.gl/qC70ut

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