Category: Other species


Our local dive club recently completed two dives for the Vancouver Aquarium Marine Science Centre’s 18th annual lingcod egg mass survey.

The survey is the result of concerns about the overfishing of this fish species and is conducted just after the spawn (January to February) when females leave the males to guard the egg masses from predation by species like sea stars. There are very few deadbeat dads in this species!

Lingcod male guarding eggs

Lingcod male guarding an egg mass (generally - the larger the egg mass, the older the female that laid it). Photo: Hildering

The data collected provide insight into the abundance and reproductive success of lingcod in B.C. and include: depth of the egg masses; their size (grapefruit , cantaloupe or watermelon sized); if the eggs are being guarded by a male; and their state of development (new, eyed or rotten). We are very fortunate that our area appears to have relatively abundant and large egg masses.

My understanding of the behaviour of these magnificent fish has now evolved  to where I take photos of the extremely territorial males guarding the large “orb of life” that is their many fertilized eggs (see the link below for a slide show). But it wasn’t always that way for me. I thought it might be entertaining to share the following much exaggerated perspective of a very new diver doing their first lingcod egg mass survey.

Eleven years ago, I had only ever done 14 dives and had never even seen a lingcod while diving. So, in preparation for the survey, I consulted my trusty field guide and felt well-prepared knowing the information below:

LINGCOD (Ophiodon elongatus)

  • Size: To 1.5 m , to 37 kg.
  • Description: Large head, mouth and teeth; dark blotches on a slender, tapering, mottled body.
  • Habitat: Adutls on rocky reefs and in kelp beds to 2,000 m; juveniles on sand and mud bottom.

But, nothing could have truly prepared me for meeting the awe-inspiring and highly dedicated lingcod Fathers for Future Generations Club.

That first experience with the survey 11 years ago led me to writing the following tongue-in-cheek “updated” field guide information in my dive log.

LINGCOD (Megadontos fishious)

  • Size: &%$#@ huge!!!!!
  • Description: Teeth sharp, large and fear inducing; species camouflaged for added surprise value; ability to make themselves appear even larger and more menacing by fanning out huge gill plates (opercula). Note: Wise for divers to retreat if this behaviour is observed.
  • Habitat: Adult males found anywhere that groups of slate carrying divers like to congregate.
  • Comment: Egg masses are said to have eyes at some stage of their development but no living diver can confirm that this is the case!

This is an awe-inspiring fish species indeed. I have even had a male knock my dive slate out of my hands during a survey. Ironically, I was recording “absent” under the column for whether a male was guarding the egg mass!

See my short slideshow on the species at this link (2.5 min).


Note that the common name of lingcod is confusing as they are not a cod nor a ling (another fish species).

For detailed information on the survey and on the biology of lingcod click here for the report on the 2010 survey (by Kevin Kaufman and Jeff Marliave).


 

While diving this morning, I came across a kelp greenling couple while they were courting (Hexagrammos decagrammus).

In addition to being fascinated by the courtship behaviour, I was struck by the intense colouration, especially of the courting male.

Mature male and female kelp greenlings look very different but I had never fully realized how their gender specific colour intensifies during courtship.

Mature males are blue/brown with blue patches but the colour of the head and eyes appears so much more stunning when the male is courting.

This 1.5 minute slideshow / video at this link shows the colouration and the courtship behaviour. Enjoy! (If having trouble viewing, choose a smaller video size at top of video’s page).


Nature gave us sockeye salmon this year. A red-scaled, bounding life source, some 34 million fish strong.

This has led to human voices shouting out in all from gratitude to greed; from delight to denial.

Predictably, sadly, there have been far too many who have been at the “greedy denial” end of the spectrum. I will not tire you with that here though.

I want to fish out two voices of sanity from the ocean of opinions. One voice is that of reporter Stephen Hume from the Vancouver Sun. The other is nine-year-old Avery Walker who I am privileged to have as a member of my Northern Vancouver Island Young Naturalists’ Club.

Stephen Hume, award-winning author,  in The Vancouver Sun: “Columnists who apparently wouldn’t know the difference between a sockeye and a sculpin cluck and scold in a Toronto newspaper. One enthusiastically advances the argument that we should whack 30 million of the 34 million returning salmon . . . . . Instead of permitting a lust for instant gratification to derail a natural process for rebuilding small stocks, now is the time for restraint, for harvest restraint is a critical investment in future abundance. So enjoy your sockeye. Be grateful for this gift from nature. But don’t let the gong show of greed sway us from good stewardship.”

Avery Walker - Salmon Superstar. Photo by Larry Walker and Anna Marchand.

Avery Walker, 9-year-old Young Naturalist, with his prize-winning submission to the Wild Salmon Circle’s “Spawning Ideas” contest: “I fish only with barbless hooks, I’ve taken all the treble hooks from the all the buzzbombs I have and replaced them with single barbless hooks. I don’t jig the fish, I fish the ones who bite. Sometimes this is really hard to do, because not all of my friends fish like this, and so they sometimes take home more fish than I do. I abide by the regulations about which salmon I can keep and which ones I can’t. I never go over my limit. Or keep undersized fish. Most of the time, I catch and release. I love to fish, and I want to be able to do it forever.”

Thank you Avery. Thank you Stephen. Thank you all who make choices that may allow us to have  . . . fish forever.

For insights into the need for precaution in managing the harvesting and threats to the Fraser River sockeye, please click here for information from “Save Our Salmon”.

Juvenile yellow-tail rockfish.

Recently, I noticed a lot of splashing in a tideline off Telegraph Cove, BC. I share my observations with you via the little video clip at the link below.

You’ll note that it looks like big rain drops are hitting the water.

I discovered that what was creating the splashing were juvenile yellow-tail rockfish feeding on zooplankton. The zooplankton, including a small species of krill, had been concentrated at the surface by the big tidal exchange. There had been almost a 4 metre exchange between high and low tide (more than 12 feet).

I also discovered a very unique larval fish in the tideline that day but will share that discovery in a future “The Marine Detective”.

Click here for the video of the yellow-tail rockfish feeding in the tideline.

Enjoy!

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