Day of the Animals (1977)

A bunch of backpackers in the wilderness run into a heap of trouble from crazed animals...
Stars a cast of several sci-fi veterans: Christopher George (Project X, The Immortal, Grizzly), Leslie Nielsen (Forbidden Planet), Paul Mantee (Robinson Crusoe on Mars), Richard Jaeckel (The Green Slime, Latitude Zero), Lynda Day George, Michael Ansara (Voyage to the Bottom of the Sea, Star Trek's Day of the Dove), Andrew Stevens (The Fury), and Ruth Roman.
I think the problem with most of these sci-fi/horror pictures of the later seventies, including the 'eco-terror' trend, is that they and the genre simply ran out of steam by the year (1977) of this film; the earlier ones, though not very good to begin with, still had some energy & poked a little fun at themselves. These later ones seemed to take themselves too seriously and were more dull. The beginning of this has some info to read, explaining in pseudo-scientific fashion what "could" happen (ozone layer, etc.), almost as if this were a documentary.  This type of gobbledygook reached a nadir a couple of years later in The Dark, where-in a similarly solemn explanation was offered for the appearance of a crazy alien from outer space.
The film moves pretty slowly; the group of backpackers, led by guide Christopher George, aren't very interesting. Ansara does OK as an Indian but Roman is downright annoying; most everyone else is forgettable. I will say this: Leslie Nielsen, billed after George, is a hoot as the defacto villain of the group. Nielsen's problem during his early Hollywood years was that he was a bit wooden playing dull heroes. Much later in life, he found a new niche in wild comedy (after Airplane-1980).
In between, he tended to ham it up as nasty sorts, as if he was preparing himself for the turn to all-out comedy.  In the one almost-clever plot development, it's revealed that not just animals are affected by the change in our atmosphere; certain people are, as well (aren't we also animals - mammals - just with more intelligence?). Nielsen, who starts out as a threatening closed-minded bully, becomes a downright dangerous psychopath by his last scene. I admit I enjoyed watching Nielsen chew up (not literally) the scenery here.
Chris and Lynda Day George were married and probably enjoyed playing their roles together out in the wilderness and getting paid for it. This didn't translate well to the audience. Bobby Porter, who plays the kid, also played a chimp in Battle For the Planet of the Apes (1973). Nielsen grabs him and calls him a little cockroach here. Most of Porter's career was as a stuntman. Not helping the slow pace are the numerous pointless shots thrown in of various creatures wandering in the woods - there's one of a tarantula, for example, crawling over a rock, meant to evoke a sinister feeling, and you expect it to bite one of the humans later. But, it doesn't. BoG's Score: 5 out of 10

Some trivia: sources say that the budget for this was $1.2 million, one of Girdler's higher budgets; Grizzly (1976) cost just under a million, while The Manitou, his biggest, cost $2.6 million.