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Nekton. Clupeidae American shad Alosa sapidissima. Engraulidae baelama anchovy Thryssa baelama. A. Bertrand. Scombridae Atlantic mackerel Scomber scombrus. Istiophoridae Striped marlin Tetrapturus audax. Molidae Sunfishes Mola mola. Cetorhinidae Basking shark Cetorhinus maximus.
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Clupeidae American shad Alosa sapidissima Engraulidae baelama anchovy Thryssa baelama
Scombridae Atlantic mackerel Scomber scombrus
Istiophoridae Striped marlin Tetrapturus audax
Molidae Sunfishes Mola mola
Cetorhinidae Basking shark Cetorhinus maximus
Myctophidae lanterfishes Gonichthys cocco Diaphus rafinesquii
www.nmfs.noaa.gov/prot_res/images/cetaceans/Pan_tropical_spotter.jpgwww.nmfs.noaa.gov/prot_res/images/cetaceans/Pan_tropical_spotter.jpg
Necktonic Organisms • Certain large crustaceans (i.e. krill) • Cephalopods (i.e. squid) • Fishes • Reptiles (i.e. sea turtles, marine iguanas) • Seabirds (Diving and swimming) • Mammals (i.e. seals, cetacean)
Trophic Flux Controls: “bottom-up”, “top-down” y “wasp-waist” Top- Down Bottom-Up Wasp-Waist (P. Cury)
Bottom-up Control P. Cury
P. Cury westerly weather North Atlantic Long term evolution between 4 trophic levels and North Sea Climate (Aebischer et al, 1990): Phytoplankton Zooplankton Kittiwake laydate Herring Kittiwake clutch Kittiwake chicks
Top-down Control P. Cury
A. Bertrand Top-down control: ‘Trophic Cascade’ concept Relative abundance Zoopl Phytopl Cod Capelin Before 1990 After 1990 Northeast Atlantic (Carscadden et al., 2001)
Top-down Control (Estes et al. 1998) P. Cury
Wasp-Waist Control P. Cury