An organism’s niche includes the range of abiotic and biotic conditions it can tolerate. 

In the case of the cottontail rabbit, its niche includes the ranges of temperature and humidity that it can tolerate, the plants that it eats, and the predatory hawks and coyotes with which it coexists.

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#Unit 10. Ecological Principles

R0<1, The population eventually declines to extinction 

R0=1, The population size remains constant

R0>1, The population increases

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#Unit 10. Ecological Principles

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#Unit 10. Ecological Principles

λ represents the finite rate of population change over some time interval, often a year

λ = N1/N0

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#Unit 10. Ecological Principles

Populations grow when R0 or λ>1, populations decline when R0 or λ<1, and are at equilibrium when R0 or λ=1

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#Unit 10. Ecological Principles

The simplest method to measure population density is to visually count the number of organisms in a population in a given habitat.

TLS Online TPP Program

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#Unit 10. Ecological Principles

Quadrats - A square frame often, but not always, measuring 50 × 50 cm.