h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Ah, to be a pelican! You'd have other pelican around to help herd fish into shallow pools and then share the feast. One hour of this gives you enough to eat, and then you have plenty of time to write the great pelican symphony or novel or whatever other example of fine art you want!

So the pelicans eat cormorants, which are endangered, but the pelicans themselves are also endangered? What a dilemma!

May I mention, though, that some species persist against all odds. I;m not saying that this is true of every species, but foxes in England have been hunted for centuries, but their population has stayed rather stable.

Do we know for sure that this isn't also the case with those cormorants and pelicans?

Hello again! Well there are ways to see if a species is in trouble. Over here we have actual counts of birds in wetlands called CWAC counts (Coordinated Waterbird Counts). These counts give very accurate numbers for waterbird populations all over the country. The thing to watch for is fast declines. That could spell trouble; there have been species that went extinct that had been considered safe, because some new factor suddenly impacted them causing them to decline rapidly, in some cases down to nothing. So ... if we see something suddenly dwindling we can try to quickly figure out what's going wrong.

Does it complicate matters if some of these species are capable of flying elsewhere? Migration is not extinction.

But I'm sure the people who count these birds know all that.

We're pretty clued-in down here, make no mistake! But you know, there's still much we don't know about migration, since we have some species that are mixed between migrating inside Africa, and migrating between Africa and Eurasia. Bird ringing can clear much of that up ...