Elephants are "on a collision course with the human race," says narrator Jason Robards in tonight's Survival Anglia special on CBS. It would seem that elephants would have the advantage in a collision course like that; but no, even these mighty descendants of the woolly mammoth are among the species endangered by encroaching civilization.

It's not poaching or hunting that threatens the elephant, according to "The Last Round-Up of the Elephants," but the destruction of the forests in which they live. The film, at 8 on Channel 9, shows how tribesmen in Assam, near the Burmese border, and in Sri Lanka are trying to protect the animal that is almost every kid's natural favorite. Their motives for doing so are selfish--the elephants are valuable members of the work force--but the outcome is still to be encouraged.

The film is slightly dry as TV nature documentaries go, but much of the footage shot by wildlife cinematographer Dieter Plage shows the Asian elephant as few other films have done. One elephant gingerly pushes over a palm with its trunk; another is subjected to the humiliation of being loaded onto a truck, as part of a relocation project that is definitely for the animal's own good. Still, it looks so forlorn peeking out the back--like Dumbo's mother.

Taming the elephants for manual labor "may appear cruel," Robards says--and yes, it does appear cruel, with no "mays" about it--but it is maintained that such a fate is preferable to alternatives like, say, extinction. Unfortunately, one of the jobs the elephants are best at is clearing forests; thus they are forced to contribute to their own undoing. Relocated elephants are carted out into the countryside, marked for identification with white numbers painted on their derrie res and introduced to a new environment, though not always successfully. Elephant Number 6 lumbers off and travels a quick 50 miles in order to return to her original stomping ground.

The program offers the hint of a happy ending. Although there may be only 40,000 Asian elephants left in the world, some societies are trying to keep them on the increasingly expressionless Face of the Earth; one of the last shots in the film finds expatriated elephants frolicking merrily in a monsoon. Nothing else weighing seven tons was ever as endearing.