Soungle.com searches a database of royalty free sound effects that you can listen to and download. It's produced by a company called Southern Codes (no, I have no idea either) and also provides access to musical instrument samples as well. The search functionality is very basic - little more than single keywords, but it did return a fairly impressive number of effects - 70 doors, 20 dogs barking, 86 for bird and so on.
This would be a really useful resource if you want to edit a video, or run a training session on bird calls, or put together presentations. Worth an explore, I think.