Lingcod are found in one place on earth: the western coast of North America. Vancouver Aquarium researchers have been studying them in the wild for 37 years. One thing we do know: lingcod populations are currently only at three to five per cent of what they were a century ago, and it has taken the last couple of decades (since restrictive regulations were put in place) for lingcod populations to start recovering, but we want to know why.
To add to our knowledge on how lingcod populations are faring, we conduct an annual Lingcod Egg Mass Survey to gather important information about this local species. The 2013 Survey takes place February 2 through March 10, 2013. During this time, divers will gather data on lingcod egg masses, such as the number, size, condition, and position of egg masses, as well as whether or not a guarding male is present. Data such as these help us determine the health of local lingcod populations.
This is a fun project for people just starting to dive or wanting to learn more about a local fish – lingcod are one of the most recognizable fish in our local waters, and everything wants to eat lingcod eggs, even sea stars. When in the business of guarding eggs, they want to be seen! Check out this video to learn more about the secret life of the lingcod.
This year, the short winter days and chilly ocean will have persuaded lingcod to mate and lay their fluffy-looking egg masses by rocky shores. We’ve been using the number of egg masses laid in a year to find out if these fish are recovering after nearly a century of intense fishing.
The secret life of the lingcod
This fish is not hard to find: lingcod can reach over a meter long, and the males aggressively guard their nests. Some lingcod have been observed guarding more than one egg mass, which is especially risky as they are easily picked off by a hungry sea lion or human hook. Egg guarding is key to this species’ survival; an unguarded egg mass is quickly shredded by greenlings, crabs, cod, or crafty sea stars.
The thousands of eggs guarded may yield only a handful of adults. Egg-laying females take three to five years to mature.
So much of lingcod lives still remain secret because we know so little about them past the 40-meter depth that divers can access. While most lingcod are territorial, migratory populations have also been observed. The lingcod we are studying live close to shore and are targets for legitimate sport fishing. By counting what we can see close to shore, we can measure population size, population age structure, success in reproduction, as well as the hidden impact of illegal fishing.
We need divers!
We need volunteers on the reef, on lookout for lingcod and their egg masses. Record the date, duration of dive, and numbers observed on that dive. Anything you observe on the dive is potentially useful so describe anything interesting – we can use photos, videos, stories, poems and songs about a lingcod dive. And remember, ‘zero lingcod’ is still useful data! For more information, visit here.
If you can’t dive, you can still hang out with fearless lingcod right here in the Vancouver Aquarium’s exhibit Treasures of the B.C. Coast. We have been raising them successfully for 30 years.