A genetic study of a species of whales sometimes targeted by Japan's scientific whaling program could aid management strategies for the animals, scientists say.

The study has helped define populations and subspecies of Bryde's whale, a medium-sized and poorly understood baleen whale, the Wildlife Conservation Society reported Thursday.

The research has confirmed the existence of two subspecies -- a larger variety that inhabits offshore waters and a smaller subspecies that frequents more coastal marine habitats.

"Very little is known about Bryde's whales in terms of where populations are distributed, the extent of their range, or even relationships among them at the population, subspecies and species levels," Columbia University researcher Francine Kershaw, lead author of the study, said. "Our genetic research will help define these groups and identify populations in need of additional protection."

Bryde's whales can grows to 50 feet in length and are found in tropical, subtropical, and warm temperate waters of the Atlantic, Pacific and Indian Oceans.

In addition to the impact of scientific whaling carried out by Japan, Bryde's whale populations are at risk from ship strikes, fisheries bycatch, hydrocarbon exploration and development in coastal waters, the researchers said.