When the patch occupancy rate (c) equals the patch extinction rate (e), patch occupancy (p) is
a. 1.5
b. 1
c. 2.0
d. 0

When the patch occupancy rate (c) equals the patch extinction rate (e), patch occupancy (P) is 0

Explanation:

According to Levin's model (1969):

dP/dt = c - e

where P represents the proportion of occupied patches.

c and e are the local immigration and extinction probabilities per patch.

Thus, the rate of change of P, written as dP/dt, tells you whether P will increase, decrease or stay the same:

The rate dP/dt is calculated by the difference between colonization or occupancy rate (c) and extinction rate (e).

c is then calculated as the number of successful colonizations of unoccupied patches as a proportion of all available patches, while e is the proportion of patches becoming empty. Notice that P can range between 0  and  1.

As a result, if the patch occupancy rate (c) equals the patch extinction rate (e), then patch occupancy P equals to 0.

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