Re: Long, long last gasp. (fwd)

[John Bois <jbois@umd5.umd.edu>]

On Sun, 1 Feb 2004, Dann Pigdon wrote:

> Even wild colonies are quite active during the day - especially since
> they must avoid predators like raptors and pythons while they roost.
> During the breeding season they have been known to form huge
> super-colonies of several million strong (something that tests both the
> eardrum and nose of any researcher). Fishing eagles and pythons hardly
> make a dent in such numbers though.

If they come together in very large colonies at one time then they are an
ephemeral resource (from a predator's perspective).  But what I'm not
understanding is how, in normal times and population densities they avoid
predation.  And, if they are accessible (because they're flying about in
daylight--and, in any case don't seem to have a very effective hiding
place) why they don't fuel a population explosion in predators?

> They don't just exist in tropical or sub-tropical areas either. Both
> Sydney and Melbourne have sizable and permanent populations.

So what's going on?  Why are they extending their range and why do they
seem to be unchecked?  I lived in Melbourne from 1950 until 1976 and
didn't see a single flying fox.  How have they been able to manage this
invasion?  Sounds like predator extirpation to me.  Or are we supplying
them with better fruit now in Victoria.
Thanks.
John Bois.