Nova Scotia scientists believe they have located the breeding ground for the endangered North Atlantic right whale in the Gulf of Maine.

The research increases the chances of survival for the species, says conservation biologist Tim Frasier of Saint Mary’s University in Halifax.

"The mating ground is particularly important," said Frasier from his DNA analysis laboratory. "If you want to conserve a species the main animals you want to protect are the ones that are reproducing."

Scientists believe the population of the ponderous mammals has dwindled to fewer than 500.

In recent years, the whales have been killed by entanglement in fishing gear, or by being hit by passing ships.

Research published by Frasier and other scientists in the journal Endangered Species Research indicates right whales breed each December and January in the Gulf of Maine's Jordan Basin. The region straddles Canadian and American waters.

The finding could be used to reroute shipping traffic — something that has already happened in the Bay of Fundy where right whales gather in the summer.

Whale promiscuity made job tough

Locating the breeding ground required a combination of aerial surveys, field data and DNA testing.

Right whales are promiscuous and mate year-round wherever they are. Males — whose four to 4.5 metre-long prehensile penis is one of the largest in the animal kingdom — have nothing to do with rearing young.

DNA testing was needed to establish paternity.

Scientists tracked back one year from when mothers give birth to calves and tried to pinpoint where the mother and fathers were at that time.

Surveys established that place as Jordan Basin in the Gulf of Maine.

"This has required a huge effort from many different people and many different research teams putting their data together," said Frasier.

"That’s the only way we could have gotten this done was with 30 years of data. It was many millions of dollars to do this."