Nova Scotia young lobster population shows no sign of decline, says DFO

Federal fisheries scientists say their most recent sampling of juvenile lobster in southwest Nova Scotia indicate a decade-long trend of abundant populations is holding steady.

"It's closer to the long-term average. Not the extreme high or low. Somewhere along the middle of what we've seen," said Adam Cook, a federal research scientist.

Canada's Fisheries and Oceans department has three sites in southwest Nova Scotia where it captures juvenilelobsters afterthey settle to the ocean floor.

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Two methodologies are used: Diver-based suction sampling;and passive collectors in boxes placed on the ocean floor. Both quantify newly-hatched and older juvenile lobsters at the end of the larval settlement season between August and October.

Fisheries and Oceanshopes settlement sampling can be a predictor of future populations when they mature to market size in seven or eight years.

"We are cautiously optimistic," Cook said of the fall 2015 survey.

Cause for caution

Cook saysthey're years away fromestablishing a baseline.

Settlement sampling in Nova Scotia and elsewhere in the Maritimes was established after lobster populations soared overthe past decade.

Many factors have been put forward to explain the increase, including a corresponding decline in the population of codfish which prey on juvenile lobster.

The department has no experience to compare with lower lobster populations in the 1980s and 1990sandsays time would also smooth out any variablesbetween sites.

"The more places where you get those extremes, the broader the variability the less certain you are of the central tendency or where the middle is, or what is the average," Cooksaid in an interview at the Bedford Institute of Oceanography.

In the Gulf of Maine, whereidentical sampling has been underway since the 1980s, recent years have shown a decline in young lobsters.

Cause for hope

Decline has not shown up in Nova Scotia's lobsters, Cook said.

"We're optimistic because things have continued to trend up and we haven't seen any indication of things moving downward quickly. That is where some of our optimism is coming from," he said.

"Our trawl surveys are still showing a large number of lobster out there. But, [we're]cautious because there is a lot of variability in the data we are collecting.

In additionto settlement samplingFisheries and Oceans also relies onlog book information from fishermen, catch rates and its own at-sea surveys to evaluate the state of the lobster stock.

"We are seeing some of the highest abundances we've seen on record," Cook said."These are some of the highest landings we've ever seen."