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Where do birds go to die2007-11-24 17:26:45

Very rarely do you see dead birds

Answers:

How long do birds live?

One might suppose that this question could be answered 鈥?indeed it often is answered 鈥?by a simple table of ages per species. Any such table is however likely to be very misleading.

A bit of background

Animals vary enormously in their reproductive strategies. Some 鈥?such as most fish 鈥?provide no care or protection to their offspring, but produce immense numbers of eggs in the hope that a few will survive. (These are known to ecologists as r-selected species.) Others produce only a few offspring but give them care and protection so that a higher proportion of those few manage to survive. (These are known as K-selected species.)

Humans are right at the extreme 鈥淜鈥?end of the spectrum. Most humans, at least in the developed world, live long enough to have children.

Birds also tend somewhat towards the 鈥淜鈥?end but not so far as humans. Passerines in particular (which include most common garden birds) produce large numbers of offspring, the majority of which do not suvive to adulthood. Great * for example produce clutches of 8-12 eggs. If all these survived to reproduce, Europe would be knee-deep in Great * within a decade or so. But many die either in the nest or soon after fledging. Many more do not make it through their first winter.

Average age

So what鈥檚 this all got to do with ages?

If you calculate the average age of a bird species, the calculation is dominated by the 70% to 80% of birds that die very young. The fact is that most bird species have an average lifespan of just a few months.