Cortes Island’s newest citizen science project, monitoring Dungeness crabs

Roy L Hales/ Cortes Currents - Cortes Island’s newest citizen science project, monitoring Dungeness crabs, was announced last Friday. Local Project leader Mike Moore, Helen Hall from the Friends of Cortes Island (FOCI) and Kelly Fretwell from the Hakai Institute joined Manda Aufochs Gillespie on CKTZ’s Folk U Friday.

Moore explained that when he was diving around Hernando Island in the early 2000s, he saw hundreds mating in the sand flats at Stag Bay.

“I recently started diving down on Hernando island again, just in the last five or six years and was really shocked. I could dive all season and not see a single Dungeness crab,” he said.

Moore cited two possible causes for their population decline:
crab traps and the “tremendous amount of fishing gear” in the ocean.
Juvenile Dungeness crabs are finding in difficult to form a shell because of the acidification of the ocean waters in the Salish sea

FOCI and the Hakai Institute have partnered on a Dungeness Crab monitoring project. They will be putting be a light crab trap in Cortes Bay. Fretwell explained that traps are being deployed in an area stretching from Southwestern and Southeastern Vancouver island up to Quadra and Cortes Islands. All of the lights will be turned on during the evening of April 15th.

“It's just a very cool visual is having all these little lights popping up around the Salish sea at the same time,” she said.

Moore added, “These traps are about 35 centimetres in diameter. They go a meter deep and float at the surface, but they hang down into the water column. They have battery operated lights that aluminate the water column. Larva plankton creatures are attracted to the lights and they'll swim towards it. It's a live trap. They just get held there under the lights. Then every two days normally, the trap keeper will come and pull it up onto the dock. in hot weather, we have to pull this trap every day.”

This is FOCI’s most recent citizen scientist project on Cortes Island. Previous ones include monitoring water quality in Hague and Gunflint Lakes, recording bird populations and observing sea star populations.

The later was another joint project with Hakai.
Fretwell observed that there were 21 people involved when this project launched on Cortes Island a year and a half ago. Now there are 100 involved in the Discovery Islands and they have collected 490 observations of sea stars.

Hall said, “Anyone can do this. You don't have to be a scientist. Anyone can take part and learn a lot more about the species and the habitats around you. it's a way of engaging people in the environment in a fun and interesting way,” said Hall.

Moore said he would like to see kids involved in the Dungeness Crab Monitoring program.

“If you want to learn more about the light trap project, you can go to https://sentinels.hakai.org/approaches/light-traps. You can also go to https://hakai.org/inaturalist/ to learn more about iNaturalist and there are links there out to our various iNaturalist projects that we have going on.”