Low power LED lights could raise Canadian snow crab catchability, according to a study presented by PHD candidate Khanh Nguyen at the fourth International Marine Conservation Congress, reported The Fish Site.

Nguyen, who is based in Marine Institute, Memorial University of Newfoundland, described in his presentation a method of raising snow crab catchability by exploiting the animal's natural reaction to lights.

The first phase of the research was conducted under laboratory circumstances, where they were focused on the responses of legally sized male snow crabs. The crabs were exposed to five different colored LED lights, blue, green, red, purple and white, and crab’s movement were measured.

The crabs did not respond significantly to red and green LED lights, but 75% of the snow crabs were inclined to move towards white and blue LEDs, while 85% shied away from purple lights.

In the second phase of his research, Nguyen took the LEDs to sea, and tested the lights on inshore fishing vessels. Newfoundland and Labrador snow crabs were caught with smaller vessels (under 20 meters), while using baited conical mesh traps stringed together with soak times ranging from 24-48 hours.

The Catch Per Unit Effort (CUPE) of the low powered LEDs were compared by embedding the different colored LEDs onto certain traps, and traps without LED enhancements were used as the control group.

White LEDs emerged as the most effective in raising CPUE, increasing the catch rate by 77% compared to the control group nets.

Improving snow crab catchability with LED lights could reduce the number of trips fisherman spend to reach the allocated catch quota, by lowering it from the typical 8-9 trips to about 5 trips, explained Nguyen.

This could reduce operational costs including fuel requirements, and improve financial viability of the snow crab industry.

Snow crab fishers have shown interest in Nguyen’s research, and have inquired about adopting the LED lights during the next crab catching season.