Seaweeds and People and of the Canadian West coast by Bridgette Clarkston

Seaweeds and PeopleRaincoast Education Society

Tofino, B.C. Canada Dr. Bridgette Clarkston© Bridgette Clarkston 2014

(all images taken by B. Clarkston unless otherwise stated).

What is a seaweed?

What is a seaweed?

•aquatic

•marine

•multicellular

•attached

•make their own food

Brainstorm: how do people use seaweed?

Brainstorm: how do people use seaweed?

• beer bong / piping

• skipping ropes

• medicine–iodine supplement

• antiseptics

• cultivate lab organisms

• food

• catching herring spawn

• baking supplements in place of gelatin

• carrageenan for cooking

• Turkish towel as toothbrush / washcloth

• garden fertilizer

• mattress stuffing

• art / music

A global perspective Images: Google search

Images: Google search

Monte Verde, Chile Images: http://www.pasthorizonspr.com/index.php/archives/10/2011/the-seaweed-trail-peopling-the-americas

Images: http://www.pasthorizonspr.com/index.php/archives/10/2011/the-seaweed-trail-peopling-the-americas

http://www.pasthorizonspr.com/index.php/archives/10/2011/the-seaweed-trail-peopling-the-americas






Japan and Nori

• harvested since 6th century

• for many centuries, nori fishers simply gathered what could find at low tide.

• cultivated since 16th century

Utagawa Hiroshige’s “One hundred famous views of Edo”, #109 (1857)

Japan and Nori

• harvested since 6th century

• for many centuries, nori fishers simply gathered what could find at low tide.

• harvest and processing into nori sheets done by hand

• cultivated since 16th century

• “pole” method invented 1821

• nets across poles 1930’s

However, yields remained modest and crops unreliable from year to year…until…

A connection was made between the Porphyra crop and the work of a scientist far, far away in Britain…

Seaweeds used in many cultures…

contemporary uses of seaweeds

Photo: algaebase.org


http://algaebase.org/


When did you last use seaweed?

1.In the last 24 hours.

2.In the last week.

3.More than a month ago.

4.Ew, never.

seaweeds have many uses…

Can we categorize our list of uses?

food, a.k.a. “sea vegetables”

Which is the sushi seaweed?









Pyropia yezoensis, a.k.a. nori





B.C. First Nations Group and (or) language family (territory) Name for seaweed (usually Porphyra)

In general, picked, fermented, dried, compressed, redried, chopped, stored, cooked in myriad of ways…

Europe

• Porphyra/Pyropia eaten in Wales, Scotland, Ireland, N. England, Norway, Finland.

• Called “laver” or “sloke”

• Pounded, stewed to jelly or mixed with oats…

• 200 tonnes collected annually in Wales until 1980’s (pollution)

Seaweed nutrition: minerals, Calcium

Dry weight (8g typical serving)

•Ulva 37% RNI*

•Cheddar cheese 5% RNI

* RNI = UK version of recommended daily intake

Kombu/konbu

WakameNoriDulseIrish moss

Sea lettuce

Seaweed nutrition: minerals, Iron

* RNI = UK version of recommended daily intake

Dry weight (8g typical serving)

•6.4mg Palmaria (dulse)

•1.6mg steak (raw sirloin)

•Bioavailability (absorption and retention unknown for most seaweeds)

•One study found lower bioavailability in Porphyra sp.

Kombu/konbu

WakameNoriDulseIrish moss

Sea lettuce

Seaweed nutrition:

fatty acids

• Humans require omega-3 and omega-6 fatty acids in diet.

• Seaweeds up to 2% dry weight of lipids, mostly fatty acids.

• In fact, are the producers of the fatty omega-3 and omega-6 fatty acids in fish, shellfish.

Seaweed nutrition:

vitamins

• Have fat-soluble and water-soluble vitamins

• Produced by seaweed to protect against damage caused by uv light

• One of few plant sources of B12.

Seaweed nutrition:

protein

• Some species relatively high in protein

• Porphyra/Pyropia can be up to 47% protein (dry weight)*

• Bioavailability improved by “physical processes” or fermentation.

*Varies by season and species

chemical extracts





chemical extracts





chemical extracts

chemical extracts





chemical extracts

Materials

•Bull kelp stipes used by some First Nations for fishing lines, ropes, bulbs as containers.

•Tough stipes of some species used to make beach hockey sticks. Holdfasts carved into round hard balls.

Where does all the seaweed come from?

Most is farmed, Nori by far the largest crop

Wild harvest too, but on smaller scale





seaweeds as inspiration

art – Euthora timburtonii example

art

design

biophilia

What about biofuels?

Which examples are new to you? Which is the most interesting to you?

Future uses and the connection to conservation

Important to collect sustainably

• If required, get a license (Alaska, Washington, California)

• Know your limits (10lbs / day wet weight in California)

How to collect seaweeds sustainably

Guidelines from: Jennifer Hahn. 2010. Pacific Feast. Skipstone.


• Don’t pick whole seaweed

• Take from blades well above growing zone (meristem)—on a kelp, this is between stipe and blade

• Use scissors or knife if possible

meristem

cut here



• Don’t pick whole seaweed

• Take from blades well above growing zone (meristem)—on a kelp, this is between stipe and blade

• Use scissors or knife if possible

cut here


• Collect only a little across the whole bed

• Collect only what you need

• Leave holdfasts

• Be aware of what you’re walking on (don’t crush the animals!)



• Collect only from clean sites

• Be respectful of traditional First Nations’ land



Thank you. Questions?

Science

Seaweeds and People and of the Canadian West coast by Bridgette Clarkston