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North Atlantic Ocean

Georges Bank - 1. Gulf of Maine. Georges Bank. 240 km (144 m). 45m (150ft) deep. Canada. “Hague Line”. USA. North Atlantic Ocean. Georges Bank - 2. Why is Georges Bank so good for cod? Great primary productivity because it is shallow so light penetrates to bottom

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North Atlantic Ocean

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  1. Georges Bank - 1 Gulf of Maine Georges Bank 240 km (144 m) 45m (150ft) deep Canada “Hague Line” USA North Atlantic Ocean

  2. Georges Bank - 2 • Why is Georges Bank so good for cod? • Great primary productivity because it is shallow so light penetrates to bottom • Cold, nutrient rich cool Labrador Current meets warm current of Gulf Stream • Extreme tides of Gulf of Maine help circulate nutrients

  3. Collapse of Fishery - 1 • Estimated biomass of predatory fishes such as cod in Atlantic has declined by 90% in last century(Christensen et al. 2003). • It is estimated that 66% of this harvest occurred in the last 50 years (Christensen et al. 2003). • How did this happen? Explanations include: • Post-war expansion of mechanized fishing fleets and development of huge “factory trawlers”

  4. Collapse of Fishery - 1 • Estimated biomass of predatory fishes such as cod in Atlantic has declined by 90% in last century(Christensen et al. 2003). • It is estimated that 66% of this harvest occurred in the last 50 years (Christensen et al. 2003). • How did this happen? Explanations include: • Post-war expansion of mechanized fishing fleets and development of huge “factory trawlers” • Popular misconception of oceans as limitless

  5. Collapse of Fishery - 1 • Estimated biomass of predatory fishes such as cod in Atlantic has declined by 90% in last century(Christensen et al. 2003). • It is estimated that 66% of this harvest occurred in the last 50 years (Christensen et al. 2003). • How did this happen? Explanations include: • Post-war expansion of mechanized fishing fleets and development of huge “factory trawlers” • Popular misconception of oceans as limitless • Aquatic environments difficult for people to envision

  6. Collapse of Fishery - 1 • Estimated biomass of predatory fishes such as cod in Atlantic has declined by 90% in last century(Christensen et al. 2003). • It is estimated that 66% of this harvest occurred in the last 50 years (Christensen et al. 2003). • How did this happen? Explanations include: • Post-war expansion of mechanized fishing fleets and development of huge “factory trawlers” • Popular misconception of oceans as limitless • Aquatic environments difficult for people to envision • Greed and lack of political will

  7. Collapse of Fishery - 1 • Estimated biomass of predatory fishes such as cod in Atlantic has declined by 90% in last century(Christensen et al. 2003). • It is estimated that 66% of this harvest occurred in the last 50 years (Christensen et al. 2003). • How did this happen? Explanations include: • Post-war expansion of mechanized fishing fleets and development of huge “factory trawlers” • Popular misconception of oceans as limitless • Aquatic environments difficult for people to envision • Greed and lack of political will • Failure to learn from previous collapses, e.g., halibut were “fished out” from Massachusetts Bay by 1850’s

  8. Collapse of Fishery - 2 • Signs of trouble were apparent by early 1970’s. Despite intensified fishing, landings of many Atlantic species had peaked and were already declining by the late 1960s. • Foreign fishing fleets, so-called “distant water” fleets, increasingly competed for fish on Georges Bank and other grounds. • Japan, Soviet Union, Poland, East and West Germany, Spain, Portugal and others • In 1976, the United States Congress passed the Magnuson Fishery Conservation and Management Act. This act established a 200-mile limit around US and banned foreign fishing within this area.

  9. Collapse of Fishery - 3 • Magnuson Act created 8 regional Fishery Management Councils (RFMC) to develop fishery management plans: • New England RFMC • Mid-Atlantic RFMC • South Atlantic RFMC • Gulf of Mexico RFMC • Pacific RFMC • North Pacific RFMC • Western Pacific RFMC • Caribbean RFMC • Two critical defects of Magnuson Act: • Councils dominated by commercial interests • Low-interest loans for fishing vessels

  10. Collapse of Fishery - 4 • Magnuson Act impacted Georges Bank cod fishing: • Since 1976, only United States and Canadian vessels have fished on Georges Bank • In the post-Magnuson act period, cod landings from Georges Bank peaked in 1982 • Hague Line boundary between United States and Canada on Georges Bank not settled until 1984; since then, each country’s fishing limited to its side. The eastern part of Georges Bank - most of which belongs to Canada - produces more cod • Changes in vessels and gear

  11. Gulf of Maine Georges Bank Area II Canada Area I “Hague Line” USA North Atlantic Ocean

  12. Response to Collapse - 1 • In 1994, NOAA (part of the Department of Commerce) closed Georges Bank Areas I and II due to collapse of ground fish • In 1996, Congress passed the Sustainable Fisheries Act, an amendment to the Magnuson Act that requires management for sustainability. Managers are to: • Identify and protect critical habitat (water and substrate) • Prevent overfishing • Rebuild stocks • Reduce bycatch

  13. Response to Collapse - 2 Some species of finfish (e.g., Atlantic herring) and shellfish, (e.g., scallops) have recovered in the closed areas and fishing has reopened. Cod have not recovered and are not likely to recover in short term. Constant commercial and political pressure to reopen fishing. US risks repeating permanent commercial collapse of cod that has happened in some Canadian waters. Perhaps only vocal public concern - similar to what happened for whales in the 1960’s - can halt this.

  14. John Dory (Zeus faber); to 90cm TL Worldwide distribution Photo by P. Wirtz

  15. Boarfish (Antigonia capros) Photo by J. Randall

  16. Squirrelfish (Holocentrus adscensionis); to 61cm TL; sounds; Western North Atlantic and Caribbean Photo by P. Wirtz

  17. Sonic muscles (SM) of squirrelfish originate on the cranium (Cr) and insert on the ribs (VR) adjacent to the swimbladder. From Carlson & Bass, 2003

  18. Silversides, Mullets, Grunion and Allies (Atheriniformes) Atlantic Silversides (Menidia menidia); 15cm TL; a key forage-fish of Atlantic coast salt marshes Photo by Don Flescher

  19. Silversides, Mullets, Grunion and Allies (Atheriniformes) White mullet (Mugil curema); 90cm max TL Catadromous Adults filter feed on algae and detritus Mugilidae 232 White Mullet Mugil curema WEB 02-519 132 mm TL

  20. Silversides, Mullets, Grunion and Allies (Atheriniformes) California Grunion (Leuresthes tenuis); to 25cm TL; spawn at highest tide line (3-4 nights after new and full moons); eggs remain in sand for ~10 days and hatch at the subsequent highest tide. Images and information from Steve Vogel, Cabrillo Marine Aquarium

  21. Needlefishes, Flyingfishes and Allies (Beloniformes) Belonidae 242 Flat Needlefish Ablennes hians WEB 02-523 725 mm TL

  22. Needlefishes, Flyingfishes and Allies (Beloniformes) Exocoetidae 244 Blackwing Flyingfish Hirundichthys rondeleti WEB 02-444 193 mm TL

  23. Pupfishes, Killifishes and Allies (Cyprinodontiformes) Sheepshead Minnow (Cyprinodon variegatus); 9cm total length; coastal marine and estuarine; can tolerate hypersaline pools.

  24. Pupfishes, Killifishes and Allies (Cyprinodontiformes) Mummichog (Fundulus heteroclitus); 15cm total length; coastal marine and estuarine; can tolerate hypersaline pools. Photos by J.F. Scarola and John Brill

  25. Sticklebacks (Gasterosteiformes: Gasterosteidae) 7 to 12 spines Bony plates on flanks and belly = Gasterosteiformes Ninespine stickleback (Pungitius pungitius); 9 cm max TL; anadromous, freshwater, brackish, marine. Male builds nest of plant debris glued together with a kidney secretion. Male guards eggs and hatchlings.

  26. Pipefishes and Seahorses (Gasterosteiformes: Syngnathidae) Tubular, pipette-like mouth Body armored with bony plates Dorsal fin Some species have a caudal fin; others have lost it Syngnathidae 281 Chain Pipefish Syngnathus louisianae WEB 02-522 229 mm TL

  27. Tubular, pipette-like mouth and “Coronet” of bony plates on head Swims with dorsal and pectoral fins; prehensile tail attaches to plants. Adults form monogamous pairs; males brood eggs for ~ 3 weeks in an external pouch known as a marsupium; hundreds of eggs in pouch Vulnerable. International trade is regulated (CITES II; May 15 2004).

  28. From Lourie, S.A., A.C.J. Vincent and H.J. Hall, 1999

  29. Common seadragon(Phyllopteryx taeniolatus); Eastern Indian Ocean

  30. Leafy seadragon(Phycodurus eques); Southern Australia (Eastern Indian Ocean) The “leaves” are skin flaps that help to camouflage the seadragon in its kelp-bed habitat.

  31. Scorpion Fishes and Allies (Scorpaeniformes) Marine Spiny Venomous Colorful Long-lived Temperate, tropical and deep waters

  32. Scorpion Fishes and Allies (Scorpaeniformes) Spotted Scorpionfish (Scorpaena plumieri); a moderately deepwater species from Western North Atlantic Scorpaenidae 291 Spotted Scorpionfish Scorpaena plumieri WEB 02-537 220 mm TL

  33. Scorpion Fishes and Allies (Scorpaeniformes) Copper Rockfish (Sebastescaurinus); 58cm max TL; Pacific Coast (Canada, to Mexico) Viviparous; planktonic larvae Photo by J. Nichols

  34. Scorpion Fishes and Allies (Scorpaeniformes) Bocaccio Rockfish (Sebastespaucispinis); 91cm max TL; Pacific Coast (Canada, to Mexico). critically endangered as of 1996; Pacific ocean perch (S. alutus), canary (S. pinniger) and widow rockfish (S. entomelas) also depleted Photo by Dan W. Gotshall

  35. Scorpion Fishes and Allies (Scorpaeniformes) • Why are species of rockfishes at risk? • The usual story of overfishing but in this case compounded by the biology of rockfishes. They are: • Slow growing, long lived (50-100 years) and slow to mature (20 years) • Low reproductive potential • Sedentary - easily fished out • Do not survive rapid trip to surface when caught

  36. Scorpion Fishes and Allies (Scorpaeniformes) 1. Searobins (Triglidae) are near-shore bottom fishes that walk on the tips of their modified pectoral fin rays Triglidae 297 Bighead Searobin Prionotus tribulus WEB 02-337 204 mm TL

  37. Triglidae 297 Blackwing Searobin Prionotus rubio WEB 02-482 347 mm TL

  38. Pufferfishes and Allies (Tetraodontiformes - commonly t-forms) A short vertebral column means an inflexible body This relates to alternative swimming modes and unusual defensive systems including spines, puffing, and toxins This in turn links to reef and near-shore habitats Two major subgroups of t-forms: “puffers” and “triggerfishes” Some place boxfishes with puffers; others with triggerfishes

  39. Pufferfishes and Allies (Tetraodontiformes - commonly t-forms) Photograph of specimen in field before preparation < 22 vertebrae Tissue sample Photograph of prepared dry skeleton Scrawled Filefish, Aluterus scriptus (Osbeck, 1765)WEB 02-479; 345 mm TL

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