Chapter+15

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1. check its stomach contents; determine trophic level of organisms within the stomach; 2. a) both have been declining over the study period; rate of decline is faster in fresh water populations; rate of decline is more constant in marine/accelerating in freshwater; b) freshwater fisheries are more established/have been overfished for longer; freshwater populations smaller/more susceptible to disruption; 3. Increasing age means Increasing size Increasing size means broader range of prey including larger fish/higher trophic level fish; 4. age correlated with trophic level; lowering of trophic level means lowering of mean age; 5. greater biomass of lower trophic level means higher sustainable yield; allows higher trophic levels to recover;

page 171 1. Both are top predators; Both occupy more than one trophic level; Both can be predator/prey of the other; Belastoma has higher productivity; 2. Ranatra and Belostoma both can be considered as secondary, tertiary and quartenary consumers; 3. metaphyton--> Hyalella-->Telebasis-->Belostoma 4. first rung is sum of metaphyton and epiphyton energy values; first rung labelled as producers or with species name; second rung is labelled primary consumers; second rung shown 5% as wide as first rung; 5. __final-initial__ x 100% = -95.3% initial 6. Some organisms can occupy more than one trophic level at the same time; some organisms can occupy different trophic levels at different points in their life cycle; 7. Determine the fraction of each organism's diet coming from each specific trophic level;

page 172 1. 12.5 degrees celsius; 2. 13-1 degrees celsius (mean annual temperature) & mean annual rainfall from 250-745 3.Four ecosystems will be affected; Amount of desert will increase. Tundra will decrease. Boreal will decrease. Temperate forest will decrease.