Tag Archives: food sources

Bullwhip Kelp (Nereocystis luetkeana)

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Walk along the beach. All kinds of things wash ashore, including kelp.

Bullwhip Kelp washed ashore

There is a good chance you can find a fresh piece of dark olive-brown Bullwhip Kelp. Storms and strong waves will occasionally tear pieces of the plant and throw them onshore. Sometimes the rough water can destroy a whole kelp forest.  

The idea of a kelp forest might be new to you. They are very similar to land, or terrestrial, forests…just wetter. A kelp forest has a canopy which supports sun-loving organisms and leaves. It also has a partially-shady middle section (with a very strong stalk) and darkly-shaded seafloor which acts as a nursery for new plants.

Where Found

Bullwhip kelp grows on rocks found in low to subtidal zones at depths up to 100 feet. It prefers semi-exposed habits and high-current areas. Offshore beds in deeper water may persist for several years.

Bullwhip kelp is found along the North American Pacific Coast from Alaska south to northwest Baja California, Mexico.

Plant Parts

Like land plants, kelp has leaves or ‘blades’ that can reach up to 13 feet long and nearly six inches wide. These leaves form the canopy cover and are often produced annually. Blades hang on for up to 18 months (depending on the weather and other conditions).

Numerous blades (30-64) sprout from a floating bladder. This bladder contains carbon monoxide which helps keep the blades in the sunny canopy.

Bladders connect to a long hollow flexible stalk, or stipe, which resembles an enlarged whip (i.e., the name sake). The stalk is very strong and has a fist-sized holdfast (think root-like structure) that grips onto the rocks.

Ecosystem support

Kelp forests offer protection and food for a variety of species besides human. This includes urchins, fish, invertebrates such as shrimp, snails (like Black turban snails), and brittle stars and worms. Marine mammals include whales, otters, seals, and sea lions, and shore bird such as great blue herons, snowy egrets, and cormorants also depend on kelp.   

Gives a whole new meaning to ‘kelp bed’ eh?

Reproduction

Kelp can form large forests or small beds. Different species of kelp often grow together favoring different depths and exposure.  

Bullwhip kelp drops mature spore patches to the seafloor near the parent’s holdfast which creates dense forests. It is the only kelp to do that.

Uses

Bullwhip kelp is edible and can be enjoyed dried, raw and/or picked. For a pickle recipe see Monterey Bay Seaweed (http://www.montereybayseaweeds.com/the-seaweed-source/tag/bullwhip+kelp).

Pacific Northwest Coastal Tribes used the kelp for creating a number of different products such as fishing lines and nets, ropes, and lightweight storage containers. It was also used for steaming and shaping various woods to create halibut fishing hooks and Yew bows.

Fresh kelp could also be eaten or included in recipes for cakes, curry, and chutney. It has also been used for pharmaceutical supplies, poultry feed, dairy products, and finishing agents.

But wait there’s more…

There are theories that kelp forests may have helped colonize the Americas. I can hear the disbelief in your laughing from here…  

Suppose that huge kelp forests stretched from northeast Asia to the northern American Pacific coasts.

These forests could have provided food and game, and buffered rough water and potentially acted as a highway for ancient colonists (and not just humans).  

Next time you see this lowly plant washed ashore and shredded from a storm, consider… “Did this plant make it possible for you to wiggle your toes in the sand today?”

Perhaps without it, explorers may not have survived the treacherous trip here. Certainly, food for thought!

REFERENCES:
–Wikipedia, Nereocytis (https://en.wikipedia.org/wiki/Nereocystis) and Kelp forests (…kelp_forests)
–Island Herbs (http://ryandrum.com/articlekelp.html)
–Bull Whip Kelp (https://bit.ly/2CINwuf)

Albacore TUNA (Thunnus alalonga)

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Where does the tuna in your sandwich come from?
               That can over there.
Is that where it lives?  
                      Mmmm it seems a little small.
How does the tuna get into the can?
                               I don’t know but probably angry.

What you know may not be what’s important.

If you have only seen something in a little can it may be difficult to envision it as a top level, hard hitting ocean predator. Tuna is more than what you see in the can.

Dressed like a rock star

Albacore Tuna are handsome fish with torpedo-shaped bodies, smooth skin, and long, streamlined fins. The pectoral fins may be at least half the length of their bodies. Their metallic, dark blue back and silvery white sides make them nearly invisible in the water.

They can grow up to nearly four feet in length and weigh almost 80 pounds. In our waters they average 20- to 30-inches and up to about 35 pounds. These fish belong to the North Pacific stock and are generally juvenile or sub-adult fish that have not spawned.

Eats like an athlete

Albacore can swim over 50 miles per hour which facilitates long annual migrations and successful predation. They have a high metabolism and thus may consume as much as 25 percent of their own weight every day. 

Albacore tuna are unique among the tunas because their primary food sources are octopus and squid, versus fish. As a top ocean carnivore, they prey on schooling stocks such as squid, sardines, anchovy, crabs, lobsters, shrimp.

Albacore predators include larger species of billfish, tuna, sharks, and humans.

Hunting and Hunters

This fish has a highly evolved circulatory system that regulates body temperature, increases muscle efficiencies, supports high metabolism, and high blood pressure, volume and hemoglobin.

All of this helps tuna increase their ability to absorb oxygen. They lack structures needed to pump oxygen rich water over their gills. To compensate they must constantly swim and keep their mouths open to breathe.

Going to School

Similarly-sized Albacore swim together in a school. Each school is very large and can be up to 19 miles wide. Migrating Albacore may cover over 50 miles each day when migrating. Migration timing and distance vary based on oceanic conditions.

There are six distinct Albacore stocks that generally do not mix (North Pacific has two groups one that heads for Baja California and the other for the coasts of Oregon and Washington). Other stocks include Atlantic and Indian oceans, and the Mediterranean Sea.

Migrations

North Pacific 2- to 4-year old Juveniles begin in spring and early summer from waters near Japan. They spawn between March and July. Females broadcast eggs near the surface for fertilization. They may release between 800,000 and 2.6 million eggs every time they spawn.

By July, they move into inshore waters 15-200 miles off the U.S. Pacific coast and hang out through September. They spend fall and winter in the western Pacific Ocean.

Management of

The migration across several international boundaries complicate specie management along with its economic importance. The gross national product of several countries depends on the tuna.

In the U.S., the National Oceanic Atmospheric Administration (NOAA) Fisheries have been tagging and studying the fish and recommending management actions to avoid overfishing. Several stocks are in significant decline and the species’ overall population trend is decreasing. Albacore are considered to be ‘Near Threatened.’

Bait and Switch

Albacore demand is sometimes fraudulently met through substitution.  Escolar (Lepidocybium flavobrunneum) has been frequently substituted, or ‘confused,’ with Albacore.

Escolar are known to create potential health problems when consumed. While it is not toxic per se it has caused enough concern for several countries to ban it.

REFERENCES:
–Oregon Dept. of Fish and Wildlife (https://myodfw.com/fishing/species/albacore-tuna, commercial landing statistics, and 2018 Albacore Annual Reports)
–NOAA Fisheries (https://www.fisheries.noaa.gov/species/pacific-albacore-tuna)
–Wikipedia Albacore (https://en.wikipedia.org/wiki/Albacore)
–The Atlantic, 59% of the tuna Americans eat is not tuna (https://www.theatlantic.com/business/archive/2013/02/59-of-the-tuna-americans-eat-is-not-tuna/273410/