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16 Cards in this Set
- Front
- Back
Herring Species
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-Blueback
-Alewife -Shad -Located throughout the Bay and in tributaries -Seasonal... leave the ocean and swim into fresh water to spawn. Late in winter and early spring |
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Alewives and Blueback Herring
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-Enter Chesapeake March to spawn in tributaries
-Move into the Bay and spend the summer -Migrate into the ocean for the winter -Both species are important forage fish |
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Menhaden
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-not a herring per se.. ocean spawners
-members of clupeidae like the herring and alewife -migrate from ocean into bay in spring... return to ocean in the fall -Dense Menhaden schools in summer -important endangered fishery |
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Atlantic Manhaden- Keystone species
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-Forked tail swim up to 2 miles/day
-Well camoflaged-light on ventral surface and darkblue on dorsal -lateral line for sensing and maintaining schools |
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Consuming Menhaden
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-omega protein very significant
-not used for human food directly since it is oily and full of small bones -the most important fish caught along Atlantic and Gulf coasts |
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Menhaden Protein
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-Only about 10 cents at dock
-Used to make feed for chickens pigs and cattle -Important food for predatory fish like mackarel bluefish and rockfish. |
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Menhaden problems
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-threatened species in teh bay.. eastern stocks
-Menhaden crash may=ecosystem crash.. they control plankton and provide forage base. |
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Menhaden problem species affects others
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-lack of menhaden makes striped bass move to other invertebrates for food... less nutritional value.
-results in loss of muscle and decrease in length to weight ratio.. long, lean stripers. |
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Menhaden- bottom up control
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-Filter feeders.. reduce phytoplankton that decrease light and cause "dead zones"
-reduce impacts of "supply-side" nutrients -The chesapeake had a benthic filter feeder-oysters and pelagic filter feeder- menhaden |
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menhaden decline continued
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-large oceanic schools no longer abundant
-industry now focuses on estuaries particularly the chesapeake |
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Decline in menhaden
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causes an increase in jellyfish
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Emiliano Zapata
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-1877-1919
-mexican agrarian reformer -revolutionist -guerilla leader 1911-1916 |
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Omega
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-argues that menhaden are not being overfished and that there are no ecological associated with decline
-they have become a convenient political target of those with concerns about commercial fishing- large boats close to shore more conspiciuous -loss of adult fish in east coast areas due to cyclic trends in population -however, others argue that the industry destroyed its own fishery and that increased catch of zeroes (fish less than a year old) will cause more problems -argues that striped bass are eating the juvenile menhaden -increasing net sizes used would decrease catch of juveniles -soy products could replace much of the menhaden used. |
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Some options
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-increase mesh size
-close fishing season after dec 1 -put the bay off limits to menhaden fishing |
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Shad in the Chesapeake
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-shad are among the first to enter the bay in february
-spawn through april in fresh water -adult shad return to sea in june -young shad remain through summer and move to sea in fall -remain at sea for 3-6 years then return to spawn |
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shad- poor mans salmon
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-historically an important fishery... abundant
-food and even fertilizer -also culturally ingrained in pa and md. shad roe and shad bakes are common in the spring |