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Four Fish ppt

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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-nchips”) 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
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