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Four Fish
Paul Greenberg
Four Fish• Wild Harvest of the Ocean is now 90 million
tons/yr. (catch = 170 billion lbs.) thus we are REMOVING more fish (per year!) than can “naturally” restock themselves…this leads to exploitation…illegal
• Amt. = 6X greater than in 1950! fishing…domestication…aquaculture…“games” in science with farming…ignorance (on purpose?) of ocean policy and…extinction? Or (at least) a 1,000 sushi dinner
• We need “4 or 5 oceans” to support our demand!
Four Fish
• “The King of Fish” (Salmon)• The (used to be) “Commoner” (Cod)• “Holiday Fish” (Bass)• “One Last Bite”(Tuna)
Four Fish• MAJOR ISSUES:
- Trophic Structure (need more “feed” than fish produced/caught and thus ruining ALL marine food webs)- This can lead to pollution/bad conditions/biomagnification of contaminants- Habitat Destruction (fishing methods hurt a lot more than target)- Livelihoods of fishermen?- Price of “demand” (to expensive to eat healthy?)
Four Fish
• MAJOR ISSUES (cont.):- “Farming” uses open ocean areas as “pens,” best use of ocean?- Are these animals really “wild?”-Maritime history lost?- Laws/Enforcement issues?
Four Fish…a travellers’ story
• Salmon lead cavemen to mouths of rivers (they came to us!)
• (Sea) Bass lead us to nearshore/coastal rocks and reefs (but in the ocean!)
• Cod lead us (so brave!) offshore to continental shelves (and long fishing trips)
• Tuna…the final frontier…leads only a true fisherman for the hunt to the open sea
Salmon
Salmon
Salmon
• 1st wave representative of human exploitation• Domestication was launched ON PURPOSE to
head of extinction
Salmon
• Wild Alaskan• Nova Scotian (lox in NY!)• Atlantic (all farmed)• Pacific (king/sockeye/pink/chum…)these are
the great migrators and best sustained (most common/cheapest in markets today) but are 40% extinct (you eat farmed)
Salmon
• THE KING OF FISH• Needs clean, free-flowing, freshwater (to
spawn)• Swim (upstream) against the current• Do not eat after they spawn so must reserve a
lot of fat to make trip back (the “good for us” fat we eat it for) thus very strong (hence name = “king”)
• (Wild) Filter Feeders (zooplankton)
Salmon
• Problem?• They typically need clean, free-flowing,
freshwater (to spawn) and are strong enough to swim (upstream) against the current
• However, we have found that only WILD species can actually do this (what few we have left) and “farmed” (that are released) genomes have lost that “instinct”
• Long Term implication???
Salmon
• Problem?• But still we farm (pg. 49 book)• PCB’s• Wild salmon “eat differently” (zooplankton)
than farmed (fish pellets) too• So? less “value” to us?? & more fish “out” to
produce them? (trophic structure NIGHTMARE)
Salmon• Future?• Eat “Wild Salmon” RARELY as the delicacy of all
delicacies! (& prices reflects)• Or eat a(n) AqaAdvantage (genetically modified)
version - eats less and is always female/sterile so doesn’t “impact” wild stock (can’t mate)
• Closed System Aquaculture (separate stocks)• Science – get them to eat something else (algae)
& impact trophic structure(s) less?• Pg. 74 book
Cod (USA)
Cod
• (Now) Lives further offshore where continental shelf slopes off (but can live/feed a lot closer)
• Gather, closer to bottom, in these areas annually to mate – a “congregation”
• But fishermen knew of this “event” and created large scale trawlers to catch them (in mass #’s)
• Large-scale trawling = habitat destruction too• Their prey collapsed as well (eat alewives/herring
– need rivers!) from mills/industrialization
Cod• Gadiform (also haddock/hake/pollack) make up 1/3 of all
britian’s (sea)food diet because it’s cheap (think “fish-n-chips”) and flaky/white (tasty!)
• Gadiforms are “lazy” (move slowly…because they live in colder waters) thus not a lot of “red” meat (muscle) and not a lot of blood through bloodline (doesn’t taste “fishy”)
• (“Lazy”) don’t travel to far/fast (easy to catch) & easy to “contain” (eat directly from surrounding environs as filter feeders…will eat almost anything but prefer small fish)
• Store oil in liver (not flesh) thus can be “stored” longer (great industrial fish)
Cod
• Used to have so many you could “walk across” the water on their backs (the “commoner”)
• Most common characteristic was its very high abundance
• Cape “Cod” (New England = most common fishing areas); closed 1994 (Fed. Gov’t)
• Now we have industrial fishing (factories) to turn it in to a “commoners” staple (canned)
Cod
• McDonald’s “Filet-o-Fish” was Cod & only $.25 (1962)
• But we “selected” for larger fish (removed from stock) & when smaller ones reproduced the genome was changed (not as viable/large)
• First fish to introduce OVERFISHING concept and cod crisis (1994) lead to the “Sustainable Fisheries Act”
• (note) Filet-o-Fish now pollack (same thing is “crab” in California Roll)
Cod• What will “replace” it? • Alaskan Pollack (now) – but issues w/ fishing
methods (mid-water trawl only?) and amt’s decreasing (increased pressure) so - what later?
• Hoki (gadiform/lives in same area), Basa, Tra and Tilapia (these are FRESHWATER FISH!) all breed easy and don’t “disrupt” oceanic food chains
• Note: All have “MSC” (Marine Stewardship Council) “certification” of Sustainability but isn’t it odd (sad!) that we’re replacing a saltwater fish w/ a freshwater species???
(Striped) Bass (local)
Chilean Sea Bass (Patagonian Toothfish)
Bass
• Means any white, meaty fish in that family but typically refers to European Sea Bass
• “Bass” means “bristle” (germanic) = 5 (odd) spines (rays) on dorsal side
• Others are: “Branzino,” “Chilean Sea Bass” (Patagonian Toothfish), Striped Bass (here!) & (the future?!) Asian Sea Bass (barramundi)
• A Perciforme (order of fish that are “perch shaped”) that can dive deep w/ a developed swim bladder thus more “white” meat w/ less bones in the way (good/easy to eat) but not too deep (easy to catch)
Bass
• “Holiday Fish” because now (pretty) expensive• Lives in shallow, coastal, waters so 1st fish we
“easy” reached (so easily outstripped by early settlers)
• Swim bladder prevents extreme depths• Anadromous: Many spawn in freshwater &
live in seawater (need both conditions)
Bass
• Humans select to “domesticate” animals that are:
- Hardy- Endowed w/ an inborn liking to man- Comfort-loving- Able to breed freely- Needful of only a min. amt. of “tending”
see pg. 90text
Are Bass good for this?…nope
• Humans selected to “domesticate” bass but:- Do not easily breed in captivity (they actually change
their hormones when stressed)- Even when they figured out how to inject artificial
hormones the fish actually “cleaved” them (again – no go)
- Eat fish in wild (need to many) or rotifers (freshwater zooplankton) in captivity but these (in high #’s) lead to bacteria and you need phytoplankton to control them (i.e. hard to feed). Tried “sea monkey” too (same issue)
- But something good did come of it…
Bass…the ROSETTA STONE?
• This was the fish (when studied) that unlocked the secrets of development for every major commercial ocean fish species.
• Hormones for breeding, dietary changes, juvenile development/needs, environmental factors and implications (light cycles needed in captivity etc.)
• Template now used for almost ALL fish we eat!
(Atlantic) Bluefin Tuna
Bluefin Tuna
Tuna
• Pgs. 206 & 215 • Deepwater zones past the continental shelf so
harder to get to…but a “true” fisherman’s” dream to catch
• “STATELESS FISH” - Deepwater zones mean they are PAST the EEZ and “regulations” are very hard to enforce
• “Gold Rush of wild food” (sushi)
Tuna• 48 species – “fastest, most powerful fish” in the
world (“tuna,” in greek, means “to dart”)• Lightening fast (+ 40 mph)• (Largest = Atlantic Bluefin) has a range that
encompasses entire ocean and can easily be 14’ and 1000-1500+ lbs.
• WARM-BLOODED (tail development for vibration…not effort!)
• Others include longfin albacore (canned) & yellowfin/bigeye (“ahi”) but not in as much danger…eventually (replace all) w/ “Jack?”
Tuna
• Of 48 species – (largest) Atlantic Bluefin most prized
• Single fish price (at market) in excess of $150,000 (hence #’s have crashed)
• Over 90% of (ABT) species extinct/overfished – why?
• Pressure and very slow growing (7 years to sexual maturity and longer for “giants”) so can’t restock popultion
Four Fish
• Now let’s return to 2 slides from the beginning…what do you think?????
Four Fish• MAJOR ISSUES:
- Trophic Structure (need more “feed” than fish produced/caught and thus ruining ALL marine food webs)- This can lead to pollution/bad conditions/biomagnification of contaminants- Habitat Destruction (fishing methods hurt a lot more than target)- Livelihoods of fishermen?- Price of “demand” (to expensive to eat healthy?)
Four Fish
• MAJOR ISSUES (cont.):- “Farming” uses open ocean areas as “pens,” best use of ocean?- Are these animals really “wild?”-Maritime history lost?- Laws/Enforcement issues?
What should you eat?• Hook and line fisheries (pay attention to
methods) for habitat destruction minimalization• Vegetarian fish (watch what you eat eats) for
lower trophic structure impact• Aquaculture species with sound husbandry• “Dining on a 500 lb. fish is the equivalent of
driving a Hummer” (don’t eat the big fish – or support industries that do!)
• What else? (MSC, BOI seafood watch etc.)• ?? Eat Whale?? (what’s the difference!?)
(LT) How to “Make it Better?”
• Pg. 246 & 252 book• Reduce global fishing pressure• Create significant no-catch areas• Global protection of species that migrate (watch
markets)• Protection of lowest trophic structure species too!• Aquaculture species that are: efficient, nondestructive
to wild systems, limited in #, adaptable, function in a polyculture
• KEEP THE LAST “WILD FOOD” WILD!
(LT) How to “Make it Better?”
• Educate yourself (& others)- Know what you order/buy (see next 2 slides)- know COOL (Country of Origin Labeling)- Know how caught- Know how preserved & shipped (i.e. “Frozen at Sea” may decrease carbon footprint)- Is “wild” really WILD? (or farmed?)- No such thing as “organic” fish
Albacore (tuna)
Bluefin (Tuna)Note: Yellowfin looks similar