The site is by and large impressively professional (try saying that ten times fast) but one usage error in a forum description keeps catching my eye:
Hearbirds Course DiscussionHearbirds teaches you to recognise birds by there songs. Discuss the course here.
This ought to say "by their songs." Yes, I'm pedantic. Comes from working in (among other disciplines) proofreading and copyreading. Can't turn off those pattern sensors!
