Us and fish
Do Now – Watch and Take Notes
 The history of the Newfoundland Cod
Fishery
 http://www.youtube.com/watch?v=3fCX6
XKzbUY
Questions:
1.
How many people in Newfoundland lost their jobs?
 How would the equivalent of that job loss affect the city
of Chicago?
2. Who else was affected by the fishery collapse?
3. What type of economic ripple effect do you think the
loss of this resource had on people? Think beyond
the fisherman.
Case Study: Newfoundland Cod
Overfishing Impacts Everyone
Tragedy of the Commons
Theory developed by Garrett Hardin in 1968
Definition:
The depletion of a shared resource by individuals, acting
independently and rationally according to each one's selfinterest, act contrary to the group's long-term best interests
by depleting the common resource.
Turn and talk: Explain this definition to each other and rewrite in your own words AND come up with an example (other
than fishing)
Tragedy of the Commons
When individuals don’t think about all parties
involved and utilize an apparently abundant
resource to extinction.
Importance of Healthy Fish Populations
– For Humans
1. Fish provide 20% of the protein consumed
by 2.6 billion people in developing
countries (Hauge et al, 2009)
2. An Est. 150 million people world-wide are
employed in the fishing industry (Hauge et al,
2009)
3. $71.5 Billion was made in export and sale of
fish and fish products in 2004.
4. Eco-Tourism impacted by ripple effect of
species loss due to one population collapse
Importance of Healthy Fish
Populations – For Humans
SUMMARY:
 Loss of major food source in many countries
Equivalent of nearly every fast food restaurant
suddenly closing and nothing replacing them.
 Loss of economic stability
 Job loss – 150 billion unemployed world-wide
 $71.5 billion revenue loss world-wide
 Economic Instability = Social Instability

Developing Nations Fishing Boats
Developed Nations Fishing Trawlers
Impacts of Overfishing on
Biodiversity and Ecosystems
1. Loss of major predators (like cod) causes shifts in
2.
3.
4.
5.
population and changes in ecosystems (Haute et al,
2009)
Migration routes of fish change due to loss of older fish
and behavioral changes to adapt to smaller school sizes.
Current fishing practices lead to high volume “bycatch”
(unwanted fish).
Trawling can cause damage to 20-80% of marine fauna
effectively destroying sea floor habitats. (Nellemann
et al, 2008:10).
Loss of biodiversity causes increases in both algae
blooms (red tide) and oxygen depletion. (Jackson et al,
2001).
Impacts of Overfishing on
Biodiversity and Ecosystems
http://youtu.be/ulucJnxT7B4?t=20s
Impacts of Overfishing on
Biodiversity and Ecosystems
SUMMARY
1.
Impacts predator/prey relationships causing booms or
crashes in non-fished populations
2.
Causes changes in evolution, behavior and migratory
patterns of current fish populations
3.
Fishing practices negatively impact non-target fish
and habitat of fish
4.
Leads to increases in algae blooms and oxygen
depletion
Untrawled Seabed VS Trawled
Seabed
Exit Slip
On a half sheet of paper with your name on it, answer
the following questions:
What is the Tragedy of the Commons, in your own
words.
2. Which of the human impacts to overfishing do you
think is most concerning? And Why?
3. Which of the biological impacts to overfishing do
you think is most concerning? And Why?
1.