1Science, 166: 72-76, 19692Kudela et al., Oceanography18: 184-197, 2005Ch. 12, Figure 2--FAO fish catch data3Example of following twocohorts through time toexamine mortality andrecruitment (populationdynamics)4Why do we care aboutcohorts, age structure,etc?It is advantageous (froma catch/valueperspective, and froman ecologicalperspective) to removefish at intermediateages…Ch. 12, Fig. 105FishingPressure• Before 1950, >90% of fish caught werefor human consumption• Since 1950, world fisheries increased6X, but only ~50% of fish go to feedhuman populations (as fish)678910Fishing and theFood Chain (Web)• To assess thisscientifically, we canassign a trophic value toeach organism• Sustainable fisheriesgenerally start with lowvalues111213Is everythingdriven by top-down impacts,primarily due tohumans?1415-Collapse of Cod-Decline of herring-Northern prawns-Argentinian hake-squid161718The Rise of “Slime”http://news.nationalgeographic.com/news/2009/10/photogalleries/ocean-mucus-sea-pictures/192021MotivationMotivation “…analyze, describe and predict FORAGING HABITAT ofAtlantic bluefin tuna in order to understandhow changes in the oceanographic settings mightinfluence their distribution.”Part of PHD thesis:ANDREAS WALLI,Ocean Sciences, UCSC22Block et al., Nature 434, 1121-1127 (28 April 2005) | doi: 10.1038/nature0346323Tank feeding experimentsTank feeding experimentswith internal temperature sensorswith internal temperature sensors2425Can we link Fish Foraging to Phytoplankton?26SeaWIFS27Capture dominant chlor_a signal in backtracked positionseg.Tuna Respond toPrimaryProduction….Overall•ABFT prefer elevated primary productivity during area restricted search (669.56 ± 468.22 mg C m2) compared to times in migration phase(190.56 ± 303.03 mg C m2) (KS test, n = 1258 days,
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