A group of researchers at Memorial University say five deep-sea fish species have declined so much they now meet the criteria to be termed critically endangered.

The researchers were involved in an extensive study which looked at 17-years of data for blue hake, spiny tail skate, spiny eel and roundnose and roughhead grenadiers in the North Atlantic Ocean off this province.

They say the species have decreased in excess of 87 per cent over nearly two decades. Additionally, the research looked at declines over a 26-year period (1978-2003) for the two grenadier species and found decline rates in excess of 93 per cent.

Their research was reported in the Jan. 5 issue of the science journal Nature.

“Our findings are incredibly alarming and they show that the ocean's ecosystem is changing,” said Jennifer Devine, a biology doctoral student at Memorial who was one of the authors of the study. “We looked at research survey data collected by the Department of Fisheries and Oceans Canada. These fish are deep sea so they live in waters greater than 400 metres and extend to depths greater than 200 metres.”

Ms. Devine worked on the report with biology professor emeritus Dr. Richard Haedrich and Krista Baker, a former master's student at Memorial. She said their study proves that the world's oceans are in trouble. The report concluded that the five species have declined so much they now meet the World Conservation Union criteria for critically endangered.

“We are talking about thousands of fish disappearing,” said Ms. Devine. “They're not all gone. If you look hard enough you can find some of these species. But conservation should be at the top of our minds if the world wants these fish to survive. And, conservation measures are being initiated in the Northwest Atlantic to protect deep-sea species.

Ms. Devine said the five species are not commonly known throughout the world. “You won't find these fish necessarily on your menu,” she added. “But there are some markets for some of the grenadiers and the other three species are caught as bycatch and discarded.”

Ms. Devine said she hopes their research work will force governments around the world to move to protect these deep-sea fish.