Reindeer:
The whalers introduced them to South Georgia, and as they get culled every year we had one sent down to Halley (Antarctic).
Reindeer are well known for boom and bust population cycles on un-predated islands, as they eat themselves out of house and home.
Good, in a beefy sort of way.
Crabeater seal:
Also Antarctic, on the peninsula. We had a biologist studying them, which seemed to involve shooting them and removing selected parts. We went round afterward to collect the bodies to feed the huskies at the next base down the coast, so we helped ourselves to some samples.
Not too good, mostly because they hadn't been bled out after shooting, and we didn't get to them quickly enough.