BIO 4130 Lecture 8: Lecture_8_Jan_30
9 Jul 2020
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Document Summary
Complete counts of individual organism in a population are often di cult or impossible. Several methods are used to estimate population size and density. Quantitative area - and volume - based counts. N = entire population, n = sample of population. Density (# individuals per unit area or per unit volume) Some data can only provide an index of population size or distribution that is related to actual size or distribution in unknown ways. Quadratsshouldberepresentativeof the entire areacoveredby thepopulation by manyquadrats as possible are used. Quadratlocations are selectedatrandom or on a regularly spared grid. Random sampling = every member of the population has an equal chance of selection. Haphazard sampling = items are picked with the goal of emulating randomness. Example afishspeciesw a totalpopulationsizeof n 20 in a lake. Sampling is performed again and 5 sh are captured (c), 1 of them is a marked sh (r for recaptured).
