OverfishingKarina AtanasovaNina IlievaIvoslav Ganchev10/7

The Problem • Catching too many fish which leads to

extinction of their population in certain areas (1)

• The rate of catching fish is higher than the rate at which fish reproduce (2)

• Current levels of fishing• It is unsustainable• The damage – considered even greater than

that of pollution (2)• Causes: need for fish; unsafe fishing methods• 1950-1994 increased with 400% (2)• 1997-1998 – 93 million tons fish caught • Recently – reduction observed (climate

changes)

“Fishing Down the Food Chain”• Aiming for smaller species that would normally not be used with a

commercial purpose, called “small-pelagic fish” (3)• Habitat – near the surface; great significance (3) • Food chains are destroyed • Only medium fish and plankton are alive• WHY?

– Big fish are caught= not eating medium fish– Medium fish stay alive– Medium fish eat small fish– No small fish– Nothing eats the plankton– (3)

Bycatch

• The bycatch – catching unwanted species while aiming for another (1)– remains unused; sometimes returned (called “discard”)– dangerous; bycatch may die after returning to the water– NMFS (National Marine Fisheries Service) call it “the problem of the 1990s”

(9)

• Many fishing methods involve bycatch which makes them damaging

• Fish dies -> Consequences for the ecosystem? Diversity?

„„The big fish, the bill fish, the groupers, the big The big fish, the bill fish, the groupers, the big things will be gone. It is happening now. If things will be gone. It is happening now. If

things go unchecked, we'll have a sea full of things go unchecked, we'll have a sea full of little horrible things that nobody wants to little horrible things that nobody wants to

eat. We might end up with a marine junkyard eat. We might end up with a marine junkyard dominated by plankton.”dominated by plankton.” – Dr. Daniel Pauly, Professor and Director of the University of

British Columbia's Fisheries Centre (8)

Damaging Methods of Fishing Bottom-trawling

• Throwing a modified net in the sea (that weights more than a ton)

• Killing many marine species• Extremely destructive (5)• The greatest bycatch (damaged in

the net) (9)• Measures: it is banned in certain

areas in the world like the South Pacific (11)

Gillnetting

• Putting a net (invisible to fish) that captures fish (9)

• Mainly used for salmon, cod, sardine (4)

• Often damages other unwanted fish/marine species (4)

• Northeast• Bycatch – large fish (ex. sharks)

(4, 9)

“Safe” Methods of Fishing

Harpooning (4)– the species can be identified before being killed

– Used for capturing large fish (ex. swordfish, bluefin tuna)

– Prevents bycatch – fish can be released easily without being damaged

Trolling (hook and line) (4)

– No damage to the fish– fish may be released after

identification if it is unwanted – Used for salmon, albacore tuna,

etc.

Other Measures

No-take zones • Better for the fish (environment)

– Fish are protected form overfishing– The fish increase in size – The variety of the species increases– The food chain is proper, the ecosystem

is restored– Example: England- lobsters have

increased 6-7 times for 5 years (10)

• Better for the industry– As the fish grow in size there are more fish to sell– The profits are more

Overall Impact

• Many fish and marine animals have been extinct and would continue to vanish

• The ecosystems are damaged• Fish decrease in size and number• The fish industry suffers from the bad effects

on the fish• Unemployment

Cod in Newfoundland (Canada)• Where: Newfoundland (Canada)• What: Cod• The Problem: decrease in cod population as

well as on the fishing industry – Impact on the environment: cod almost extinct – The industry: unemployment; no fishing industry

(7)

• Measures taken: In 2003 fishing cod was banned in the area

Bluefin Tuna in the Mediterranean• Where: Mediterranean• What: Bluefin Tuna • The Problem: the problem with overfishing there has

been existing for long time – Impact on the environment: number of tuna has

dramatically decreased – The industry: industrial fishing – mainly

responsible for the problem• Measures taken: there are plans for the fishing to be

banned there during the season when tuna reproduces (6)

Works Cited

• 1. Koster, Pepijn. "Overfishing - A Global Disaster". Overfishing. 2007. Web. 8 June 2010 <http://overfishing.org/pages/what_is_overfishing.php>.

• 2. "Overfishing". See the Sea. Web. 8 June 2010 <http://see-the-sea.org/topics/commerce/overfishing.htm>. • 3. "FISHING DOWN THE FOOD CHAIN". Green Peace. Web. 8 June 2010

<http://archive.greenpeace.org/comms/fish/part3.html>. • 4. "Fishing Methods". Monterey Bay Aquarium. Web. 8 June 2010

<http://www.montereybayaquarium.org/cr/cr_seafoodwatch/sfw_gear.aspx>. • 5. "Bottom Trawling: Overview". Oceana. Web. 8 June 2010 <http://na.oceana.org/en/our-work/promote-responsible-

fishing/bottom-trawling/overview>. • 6. "Soon no bluefin tuna to be fished in the Mediterranean". WWF. 11 Sept 2006. Web. 8 June 2010

<http://www.wwf.org.au/news/soon-no-bluefin-tuna-to-be-fished-in-the-mediterranean/>. • 7. "Cod's warning from Newfoundland". BBC News. 16 Dec 2002. Web. 8 June 2010

<http://news.bbc.co.uk/2/hi/science/nature/2580733.stm>. • 8. Koster, Pepijn. "Overfishing - A Global Disaster". Overfishing. 2007. Web. 15 June 2010

<http://overfishing.org/pages/why_is_overfishing_a_problem.php>• 9. Castro, Kathleen, Williams. “Bycatch”. Rhode Island Sea Grant. 2003. Web. 15 June 2010

< http://seagrant.gso.uri.edu/factsheets/Bycatch.html> • 10 . "Marine No-take Zones Are Succeeding beyond Expectations." Conservation and Environmental Science News. Web. 15

June 2010. <http://news.mongabay.com/2008/0716-hance_fishing.html>.• 11 ."Visible from Space Bottom Trawling Impacts." EurekAlert! - Science News. Web. 06 June 2010.

<http://www.eurekalert.org/pub_releases/2008-02/s-bti021508.php>.• http://privatelibrary.typepad.com/.a/6a01156f7ea6f7970b0120a566f154970c-800wi• http://www.oceanconservancy.org/images/content/pagebuilder/23588.jpg• http://4.bp.blogspot.com/_4CTvIprhy6M/SxWbINCA1JI/AAAAAAAAAMU/tuRAVAyOsRU/s1600/ltompzones.gif• http://moldychum.typepad.com/moldy_chum/images/2008/08/11/gillnet_damage.jpg• http://www.greenpeace.org/raw/image_full/australia/admin/image-library2/before-and-after-view-of-botto.jpg• http://www.buyecofriendlyproducts.com/wp-content/uploads/2009/07/Seafood-farming.jpg• http://photos.mongabay.com/08/0108_Overfishing.jpg• http://endoftheline.com/files/10021232140490fish-on-slab-550.jpg• http://www.montereybayaquarium.org/cr/cr_seafoodwatch/content/images/gear/harpooning4.jpg