Tag Archives: Fisheries

The California Halibut Part 1

First, they wait, buried up to their eyes…  As soon as their prey is within reach…AMBUSHl!  TEETH! GOT EM. And guess what? Halibut can chase their food as well, even leaping out of the water to do so.. if it’s their favorite (anchovies)…  Who doesn’t love anchovies?!

california halibut

Paralichthys californicus, the California Halibut, is a large flatfish found in nearshore waters, though they can be found as deep as 600ft.  Full grown halibut can get up to 5ft and 72lbs. You may see more of them in shallow waters from February to September because this is when the adults migrate from the continental shelf to spawn.  Juveniles spend their days in shallow-water bays and estuaries, making them especially vulnerable to habitat destruction by human activities such as dredging and pollution. Let’s be careful, friends!

california halibut 1

Halibut, despite what you may think, are laterally flattened fish, as opposed to dorso-ventrally flattened.  One side of their body always faces up, and the other always faces down, with the halibut always swimming on its same side.  With both eyes on the top facing side of their body, halibut rely heavily on a visual ambush as a method for feeding. They may be hard to spot due to their ability to change their skin pattern and camouflage with sandy and rocky bottom terrain, but this helps them to ambush their prey by catching them off guard.  

california halibut 2These fish are most abundant from central California to Baja california, and tip the charts as far as “yum” factor.  In fact, California halibut is one of the most important commercially-fished species among all state-managed fisheries.  To learn more about halibut, like how its eyes migrate to one side of its face, look out for part two!

SOURCES

comic: http://talesofabsurdity.com/comic/today-in-fish-news/

https://www.montereybayaquarium.org/animal-guide/fishes/california-halibut

https://www.wildlife.ca.gov/Conservation/Marine/NCCFRMP/Halibut-Studies

What’s Up with Upwelling?

It’s a universal understanding amongst all fishermen (and women!) that there are good fishing days, and most definitely bad fishing days. Sometimes all it takes is being in the right place at the right time or maybe even sporting some good ocean karma. There is, although, some technicality and logic behind it all to ensure the most optimum of catching days. It may be hitting up the right location, using the right bait, or stalking bait-balls offshore all afternoon. But what initially attracts the fish to congregate in these places? The obvious answer is food, which could be from a variety of sources. One of those sources is upwelling.

coastalupwellingUpwelling occurs all throughout the globe and in different natures. Essentially what happens is surface water along coastal shores is being pushed offshore by the influence of steady winds. As this happens, the pushed out surface water is being replaced by bottom water that is being drawn up through a current. This bottom water is cold and high in nutritious goodies. We see this exactly at the equator where trade winds blow from east to west drawing water away from South America and towards Indonesia. Prime fishing spots are located just off the coast of Ecuador and Peru. nutrientupwellingAlternatively along the California coastline, winds blow southward from Alaska towards Baja. Here, coastal waters, with the influence of the earth’s rotation, are instead pushed out 90 degrees from the direction of the wind and travel out into the Pacific. We call this process Ekman Transport where our rotating earth creates a force that drags the wind-induced currents to the right in the northern hemisphere. This is reversed in the southern hemisphere where it would travel to the left of the wind. We don’t see this happen at the equator, although, because the earth is wider and spins faster there. Ultimately, the same result occurs where water is transported away from the coast and cold, nutrient-rich waters from the bottom are moved to the surface.

This transport of nutritious bottom water along the California Coast promotes prime fishing, especially for local fisheries in our area. The next time you go fishing and can’t find that trusty bait ball of yours, stick close to the shore. Also keep in mind how this natural process might change this upcoming year with El Niño. Typically, strong dissipation in coastal upwelling is observed more south around the equator during this type of event, but we may see some changes along the Southern California coast.

Written By: John Cornett

Photo Credits:
Coastal Upwelling – https://www.climate.gov/news-features/features/upwelling-crisis-ocean-acidification
Nutrient Upwelling – http://oceanservice.noaa.gov/facts/upwelling.html

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