BIO220H1 Lecture Notes - Lecture 5: Escapement, Overfishing, Logistic Function
38
BIO220H1 Full Course Notes
Verified Note
38 documents
Document Summary
5 ecology and evolution of harvested populations i. Humans harvest plants, animals, other products from natural world. Some harvesting is inevitable for living organisms to survive: energy, biomass, nutrients. Simple models of species growth and harvesting strategies. Harvesting out the recruitment (the new individuals) Population able to grow, harvest new population, and same base continue to grow. Dt = change in time r= intrinsic rate of population growth of the species if left unchecked, population will grow exponentially. Harvest k/2 individuals per year: population is at maximum growth rate. Inflection point: maximum rate of population increase: multiplied per capita rate of increase and population size. Affect of harvesting on demographics of harvested species. Harvest k/2 individuals of each species per year: k/2 = maximum sustained yield (msy) Population always in region of max growth: highest chances of replenishment. E. g. , stock size and fishing effort consequences. Despite msy, there is economic pressure to harvest more.
