cassowary biology

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tompm
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cassowary biology

Does anyone know the answer to any of those questions?:

- does fertility decrease with age? ("Our"male cassowary is more than 35 years old)

- how long does it take the female to produce another egg after laying one?

-apparently the male does not start brooding the eggs until the clutch is complete; how long can the  eggs survive in the open (this year the male ended up with the enormous number of at least 8 eggs, the first egg would have been exposed to the elements for about 5 weeks).

-what is a cassowary's life expectancy?

pacman
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sorry I can not answer your questions but will be interested in the answers when received

Peter

tompm
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Isn't it amazing and sad, how little is known about such a special bird?!

Christina

Qyn
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From what I can gather from a number of sources there is a great deal of conflicting information about the Cassowary, especially in the wild due their solitary and shy behaviour, but the expected lifespan is anywhere up to 60 years in captivity (a cassowary lived to 61 years at the Healesville Sanctuary) and maybe half that in the wild but that would be hard to ascertain I would think considering their habitat.

Most long-lived animals other than female humans remain fertile, even if not as potent, for most of their lives, so a 35 year old male cassowary probably is fertile even if less so than at an earlier age. The female may mate with different males one after another and is supposed to stay with each male long enough to dig a 4-inch nest in the ground where she lays three to eight eggs - from different sources it seems she either lays them all at once or up to 4 days apart (according to this link). The male sits on the eggs and cares for the baby cassowaries after the female leaves. Incubation takes about 50 days (can take 7-8 weeks). The chicks may stay with their father for up to 18 months (usually around 9 months) before going off on their own.

I read in one place that the male does not always sit on the nest but may guard the nest area from nearby however the hatching success rate is usually only about 50% in any case so maybe those left unattended, as in the egg you mentioned, may not hatch due to that inattention.

It is quite interesting to research but as I said the information is very variable.

I hope you update this thread to let us know the outcome.

Alison
~~~~~~
"the earth is not only for humans, but for all animals and living things."

tompm
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Thanks for the link, Alison!

This year is the first time, that someone found "our"cassowary's nest. For fear of causing him to abandon the eggs, it is not being observed regularily, and we never went near the area.

The female spent several weeks adding to the clutch and he has been presumably brooding it since mid July. As far as I know, he does not leave the nest once he starts brooding. We certainly have not seen him in our garden for the last 6-7 weeks (and the nest is pretty close by).

A local conservation group has started to organize collection and analysis of cassowary droppings to get some more facts on the numbers and relationships of the local cassowary population.

I shall post photos of dad with his new chicks as soon as he starts to visit us again.

Christina

Qyn
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Thanks Christina I would be interested to see the photos or read what else you discover.

Alison
~~~~~~
"the earth is not only for humans, but for all animals and living things."

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