The following is based upon the estimated population sizes (figures taken from the British Wildlife Centre) of some of the country's indiginous mammels, starting with the most common and working up to the rarest. All estimates relate to populations pre breeding season.

0--Mole (est. pop. 31,000,000)
1--Hedgehog (est. pop. 1,555,000)
10--Stoat (est. pop. 462,000)
50--Red Deer (est. pop. 316,000)
250--Badger (est. pop. 275,000)
500--Fox (est. pop. 258,000)
750--Red Squirrel (est. pop. 160,000)
1000--Otter (est. pop. 12,900)
5000--Wild Cat (est. pop. 2,000)

I like this set, as I'm sure the number of posters with each number of posts follows a similar pattern.

Very clever! I can tell this contest is going to be a tough one as well!

Kingfisher