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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
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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 • 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 • (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???
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!
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