1. Humans and the Sea -- Fisheries, management, and sampling
Millions of people depend on fisheries… in what ways?
Food
86 million tons/year
Jobs
Products & materials
Recreation & entertainment
Sport fishing
Diving & tourism
Aquarium trade

2. …thus, competition for resources
Lots of people in the world… and, like other natural predator/prey relationships, we take advantage and harvest many marine organisms
…thus, competition for resources
Marine ecosystems provide over 30% of worldwide animal protein consumption
How much is this?

3. Are these levels sustainable? How do we prevent overfishing?
Depends on what, where, and current practices

4. …stresses on fisheries
What is the 2010 demand for fish?
10-40 million tons above production
Cultural practices, consumption, etc., varies worldwide
E.g. average fish consumption/person/year
Japan = 37.7 lbs
U.S. = 16.6 lbs

5. Where are the richest fishing grounds?
Areas of upwelling, bordering continental shelf where primary production is higher
Most of the largest takes are around industrial nations
Exploited for the longest time
Most fishing grounds in Atlantic, Pacific, Mediterranean are in decline or exhausted
Why and How is this happening?

6. Gill net: Northeast and worldwide
Fig. 17.6
Gill net: Northeast and worldwide
panel of webbing of clear monofilament line; can be set at any depth; fish can’t see the net, so they swim right into it and are caught.
Lots of bycatch (“junk”/non-target) -- animals that are too large to pass through the webbing (mammals, turtles, etc.)
Purse seines:
Vertical, weighted net encircling aggregates; pulls bottom closed (drawstring) preventing fish from swimming down
Unintended bycatch; i.e. dolphin, sharks, sea turtles
Hook and line, and long-line:
Commercial rigs can setup miles of unselective longlines (lots of bycatch)
hard to be selective with this gear…but, possible. E.g., choosing bait, jigs, lures, and hook sizes known to catch their target species.
Trawls / Bottom trawl: single most important fishing method in the Northeast
produces the most noticeable bycatch problem & demolishes the environment
bottom trawl is a funnel-shaped net that is dragged on the bottom of the sea
Mortality: damaged in the net, brought up from the depths too quickly, or thrown back too late.

7. What are the most important fish?
Schooling fish
Herring, sardines, anchovies…
Over continental shelf & upwelling areas
Caught by purse seines
Demersal cold-water fish
Cod, pollock, haddock…
E.g. Alaska pollock is largest fishery of U.S.
Caught by trawls
Over exploited; closed many fisheries in the last decade
Open-ocean fish
Tuna (skipjack, yellowfin, albacore, bigeye, bluefin)
Caught by seines, longlines, and gill nets

12. Can we use methods that are more sustainable and environmentally responsible?
Harpooning
Harpooners catch large, pelagic predators such as bluefin tuna and swordfish.
Hook and Line
Hook and liners target a variety of fish, ranging from open ocean swimmers, like tuna and mahi mahi, to bottom dwellers, like cod
Trolling
Trollers catch fish that will follow a moving lure or bait, such as salmon, mahi mahi and albacore tuna.

13. Policies, regulations, & enforcement
Fig
Policies, regulations, & enforcement
Balance between population size, natural mortality, and fisheries
Sustainable?
# of fish caught ≤ # fish reproduced
Use sustainable fishing methods (globally, change our ways) to prevent population / fisheries collapse

14. Research and Restoration provides evidence/data to inform regulations

15. “spaghetti” tags
Archival tags
Satellite tags
Acoustic telemetry

16. Mariculture / Aquaculture
Fig
Mariculture / Aquaculture
Farming
Open vs. closed
Pros vs. Cons
High production at expense to environment; ie, wild populations, disease, pollution, etc.
Use of genetics & biotech
Faster growth, disease resistance, etc.
Salmon, shrimp

28. Human Impacts – our role, impacts, and responsibilities
Habitat destruction
Fisheries
Resource management
Recreation
Aquaculture
Pollution
Coastal runoff
Sewage
Oil
Introduced species
Invasive / pest species
What can we do instead?
MPA
Marine Protected Areas
Know our impacts and respect that we are just one species of nature
Be an informed consumer
Reduce, reuse, recycle