SCIENCE LAB SCALES : FISH

Stork Of The Sea

While on dad duty, this fish carries a mouthful of babies

Lurking among the underwater plants in Australia's ponds and streams is a fish called the mouth almighty.

The species is named for its impressive jaws, which snap up passing prey. But the males also use their almighty mouths to gently carry as many as hundreds of babies.

The dads do this oral caretaking, called mouthbrooding, for two or three weeks at a time. Like other mouthbrooding fish, they do so at great personal cost. Yet, according to a new study, mouth almighty fathers sometimes carry babies that aren't their own.

''If it's true, it's actually pretty neat,'' said Tony Wilson, an evolutionary biologist at Brooklyn College who wasn't involved in the research.

The study's lead author, Janine Abecia, is a Ph.D candidate in Australia, where she has been studying the mouth almighty, or Glossamia aprion, as well as the blue catfish Neoarius graeffei. Both live in Australia.

Fathers of both species scoop fertilized eggs into their mouths and carry them until after the young have hatched.

Her research has suggested these two species don't eat at all when they're on dad duty. ''I opened up the stomachs of mouthbrooders, and they were empty,'' Mrs. Abecia said.

Research in other kinds of mouthbrooders - which can be fathers or mothers, depending on the species - has shown that they don't eat either.

Having a mouth stuffed with offspring may also make it hard to breathe. And it seems to slow down the parent, potentially making it harder to escape predators, Mrs. Abecia said. [Elizabeth Preston].