Just saw this and thought I would pass it on. eNature is offering free wildlife ringtones for your phone: http://wild.enature.com/ringtones/
Note the links ("mating calls", "migratory birds", etc) about 1/2 way down the page to find other wildlife ringtones. Looks like this is a new (Beta) feature for this site, so hopefully they will be adding additional animals/birds to the list.
Wildlife Ringtones
