2. What conclusion can you draw from this graph?

3. Oceans today contain only one-tenth of the large-bodied animals they once did

4. Emptying the oceans
We are placing unprecedented pressure on marine resources
Half the world’s marine fish populations are fully exploited
25% of fish population are overexploited and heading to extinction
Total fisheries catch leveled off after 1998, despite increased fishing effort
It is predicted that populations of all ocean species we fish for today will collapse by the year 2048

5. The total global fisheries catch has increased

6. (kilograms per person) World Fish Catch Per Person
Per Capita Fish Catch 25 20 15 10 5
1950
1970
1960
2000
1990
1980
(kilograms per person)
Per capita catch
Year
World Fish Catch Per Person

7. (thousands of metric tons)
Fish Population Estimates
800
600
400
200
1960
1970
1980
1990
2000
Year 80 70 60 50 40 30 20
(thousands of metric tons)
Harvest
(kilograms/tow)
Abundance 10

8. We have long overfished
People began depleting sea life centuries ago
Some species hunted to extinction: Steller’s sea cow, Atlantic gray whale, Caribbean monk seal
Overharvesting of Chesapeake Bay oyster beds led to the collapse of its fishery, eutrophication, and hypoxia
Decreased sea turtle populations causes overgrowth of sea grass and can cause sea grass wasting disease
People never imagined that groundfish could be depleted
New approaches or technologies increased catch rates

9. A Systems View

10. Sonar
Uses sound waves that allow fishermen to quickly locate fish and/or see the bottom
Targets specific species
Image:

11. Fishing has industrialized
Factory fishing = highly industrialized, huge vessels use powerful technologies to capture fish in huge volumes
Even process and freeze their catches while at sea
Driftnets for schools of herring, sardines, mackerel, sharks
Longline fishing for tuna and swordfish
Trawling for pelagic fish and groundfish

12. Fishing practices kill nontarget animals
By-catch = the accidental capture of animals
Driftnetting drowns dolphins, turtles, and seals
Fish die from air exposure on deck
Banned or restricted by many nations
Longline fishing kills turtles, sharks, and albatrosses
300,000 seabirds die each year
Bottom-trawling destroys communities
Likened to clear-cutting and strip mining

13. Modern fishing fleets deplete marine life rapidly
Grand Banks cod have been fished for centuries
Catches more than doubled with immense industrial trawlers
Record-high catches lasted only 10 years

14. Industrialized fishing depletes populations
Catch rates drop precipitously with industrialized fishing
90% of large-bodied fish and sharks are eliminated within 10 years
Populations stabilize at 10% of their former levels
Marine communities may have been very different before industrial fishing
Removing animals at higher trophic levels allows prey to proliferate and change communities

15. Several factors mask declines
Industrialized fishing has depleted stocks, global catch has remained stable for the past 20 years
Fishing fleets travel longer distances to reach less- fished portions of the ocean
Fleets spend more time fishing and have been setting out more nets and lines, increasing effort to catch the same number of fish
Improved technologies: faster ships, sonar mapping, satellite navigation, thermal sensing, aerial spotting
Data supplied to international monitoring agencies may be false

16. We are “fishing down the food chain”
Figures on total global catch do not relate the species, age, and size of fish harvested
As fishing increases, the size and age of fish caught decline
10-year-old cod, once common, are now rare
As species become too rare to fish, fleets target other species
Shifting from large, desirable species to smaller, less desirable ones
Entails catching species at lower trophic levels

17. Consumer choices influence fishing practices
Buy ecolabeled seafood
Dolphin-safe tuna
Consumers don’t know how their seafood was caught
Nonprofit organizations have devised guides for consumers
Best choices: farmed catfish and caviar, sardines, Canadian snow crab
Avoid: Atlantic cod, wild-caught caviar, sharks, farmed salmon

18. The Big Question Fish Populations are declining
The Human Population is increasing exponentially
What can be done to sustain fish as a viable food resource for the human population?
What YOU can do: Choose to eat sustainably harvested seafood

19. Aquaculture Methods Is Aquaculture the Answer? Trade-Offs Aquaculture
Highly efficient
High yield in small
volume of water
Increased yields
through cross-
breeding and genetic
engineering
Can reduce over-
harvesting of
conventional fisheries
Little use of fuel
Profit not tied to price
of oil
High profits
Advantages
Large inputs of land, feed,
And water needed
Produces large and
concentrated outputs of
waste
Destroys mangrove forests
Increased grain production
needed to feed some
species
Fish can be killed by
pesticide runoff from
nearby cropland
Dense populations
vulnerable to disease
Tanks too contaminated to
use after about 5 years
Disadvantages
Trade-Offs
Aquaculture
Aquaculture Methods
Is Aquaculture
the Answer?

20. More Sustainable Aquaculture
Reduce use of fishmeal as a feed to reduce depletion of other fish
Improve pollution management of aquaculture wastes
Reduce escape of aquaculture species into the wild
Restrict location of fish farms to reduce loss of mangrove forests and other threatened areas
Farm some aquaculture species (such as salmon and cobia) in deeply submerged cages to protect them from wave action and predators and allow dilution of wastes into the ocean
Set up a system for certifying sustainable forms of aquaculture
Solutions
More Sustainable Aquaculture

21. Relevant Laws UN Law of the Seas
Magnuson-Stevens Fisheries Management and Conservation Act (Magnuson Act)
Marine Sanctuaries Act
Oceans Act of 2000
Endangered Species Act (ESA)
Convention on International Trade in Endangered Species (CITES)
Lacey Act of 1900

22. Laws Related to Fishery Management
Magnuson Act
Establishes 200 mile fishing area
Set up regional councils that
Set quotas
Set size limits
Set seasons
Protects habitat
Minimizes bycatch
Rebuilds overfished stocks
UN Law of the Seas
Nations have jurisdiction over Exclusive Economic Zones (200 Miles)
Sea Floor sovereignty up to 12 miles offshore
Allows for Individual Transferable Quotas which can be sold to others

23. Fisheries management Based on maximum sustained yield
Maximal harvest while keeping fish available for the future
Managers may limit the harvested or restrict gear used
Despite management, stocks have plummeted
It is time to rethink fisheries management
Ecosystem-based management
Shift away from species and toward the larger ecosystem
Consider the impacts of fishing on habitat and species interactions
Set aside areas of oceans free from human interference

24. We can protect areas in the ocean
Marine protected areas (MPAs) = established along the coastlines of developed countries
Still allow fishing or other extractive activities
Marine reserves = areas where fishing is prohibited
Leave ecosystems intact, without human interference
Improve fisheries, because young fish will disperse into surrounding areas
Many commercial, recreation fishers, and businesses do not support reserves

25. Reserves work for both fish and fisheries
Found that reserves do work as win-win solutions
Overall benefits included…
Boosting fish biomass
Boosting total catch
Increasing fish size
Benefits inside reserve boundaries included…
Rapid and long-term increases in marine organisms
Decrease mortality and habitat destruction
Lessen the likelihood of extirpation of species

26. Areas outside reserves also benefit
Benefits included…
A “spillover effect” when individuals of protected species spread outside reserves
Larvae of species protected within reserves “seed the seas” outside reserves
Improved fishing and ecotourism

27. How should reserves be designed?
20-50% of the ocean should be protected in no-take reserves
How large?
How many?
Where?
Involving fishers is crucial fisheries in coming with these answers

28. Laws Related to Habitat Protection
Oceans Act of 2000
Established Presidential Commission to
Examine Federal Ocean Policy
Promote protection of marine environments
Prevent marine pollution
Marine Sanctuaries Act
Protects habitat of marine organisms
Protects animals from being harvested in that area

29. Laws Related to Species Protection
ESA
Identifies and lists endangered species
Prohibits the harm or harvesting of listed species
Protects habitat
CITES
Identifies and lists endangered species
Prohibits international trade in listed species
Lacey Act of 1900
Prohibits sale of illegally harvested species
Forces legal methods

30. Conclusion
Oceans cover most of our planet and contain diverse topography and ecosystems
We are learning about the oceans and coastal environments, intensifying our use their resources and causing severe impacts
Setting aside protected areas of the ocean can serve to maintain natural systems and enhance fisheries
We may once again attain the ecological systems that once flourished in our waters

31. QUESTION: Review
Which of the following does not mask the decline of fisheries?
Fishing fleets travel longer distances
Fishing fleets spend more time fishing
Fishing fleets use traditional methods of fishing
Data supplied to monitoring agencies may be false
Answer: c

32. QUESTION: Review
Marine reserves have all the following benefits except:
Fishing increases in the reserve
The size of fish increases
Larvae can “seed” areas outside the reserve
Decreased mortality and habitat destruction
Answer: a

33. QUESTION: Interpreting Graphs and Data
What does this graph show about the future of global fisheries catch?
China will be a major player in applying fishing pressure
China will be player a smaller role in applying fishing pressure
The world will decrease its fishing pressure
The U.S. is not included in this graph
Answer: b

34. QUESTION: Interpreting Graphs and Data
Which conclusion can you draw from this graph?
Oceans today contain far fewer fish
Oceans today contain far more fish
It is easier to find fish today
There is little correlation between fishing and fish stocks
Answer: b

35. QUESTION: Viewpoints
If a developer wants to build a community on an estuary, providing jobs but eliminating the marsh, what should be done?
Let the developer build; we need the jobs
Let the developer build, but make him/her pay for any damage from storms
Let the surrounding landowners vote whether to let the developer build
Prevent the development; the potential damage is too great
Answer: any

36. QUESTION: Viewpoints
Do you plan to alter your decisions about eating seafood?
Yes; I will be more selective about what I eat
No; I will continue to eat the same type and amount of seafood as always
Answer: any

37. Fishing Methods Bycatch:
Spotter airplane
Fish farming
in cage
Trawler
fishing
Purse-seine
sonar
trawl flap
trawl
lines
trawl bag
Long line fishing
lines with
hooks
Drift-net fishing
fish caught
by gills
float
buoy
fish school
Bycatch:
Different types of fishing practices result in different animal/species being killed as bycatch:
Nets kill dolphins, porpoises and whales
Longline fishing kills birds, and
Bottom trawling devastates marine ecosystems.