Bird library

There are natural history libraries where most/all fo the books are field guide and art books. Not sure they are publically open though.

I stayed in a Scottish manor a couple of years back that had one - obviously the interest of some former Lord who had a few hundred or so.

This is what you were dreaming of, perodicticus:
http://www.ouls.ox.ac.uk/isbes/alexander

Edited for typo

Another possibility:

http://www.birds.cornell.edu/Adelson

Hello Perodicticus! That sounds like a very pleasant dream. Yes, there are many brick-and-mortar bird libraries. I would guess that most countries have at least one library devoted purely to birds. Here it is the Phelps Collection library (no on-line catalogue). If you have any interest at all in birds, you can quite easily spend a day looking through the archives there. The aforementioned Alexander Library at Oxford is truly stunning as is the library at Tring (http://www.nhm.ac.uk/research-curation/library/index.html), not just for the size of their holdings, but also for the historical significance of much of the material.