an article in The Observer about Radio 4 that managed to describe keen listeners of the Today programme as "eagle-eared". Eagles, naturally, being well-known for their large and splendid ears.
If you check out the web version of the article (which I've just linked to), you'll see that the phrase in question occurs in the third par.
Googling "eagle-eared" leads to 2,810 results, a surprisingly high figure. Take out "eagle-eared bat", however, and you are left with only 329. So perhaps the phrase should be "eagle-eared-bat-eared"...
And does anyone remember the 1980s cartoon BraveStarr? The eponymous hero had, among other attributes, "eyes of the hawk" and "ears of the wolf" – or was it the other way round? Perhaps this YouTube video of the intro will refresh my memory...