Ecology

Does model averaging make sense?

Brian Cade published a scathing condemnation of current statistical practices in ecology. It promises to be highly influential; I have seen it cited by reviewers already. I agree with a great many points Brian raised. I also disagree with one very central point.

Accounting for exposure days

Every year I suggest a student use Terry Shaffer’s log exposure models for nest survival (Shaffer 2004). And every year I spend hours trying to figure out why the code in the help section of ?family doesn’t work. So this year I’m writing it down.

How do predators change population growth, part II?

Last week I starting thinking about how predation might affect a species that otherwise experiences logistic growth due to intra-specific competition. I looked at predators with both Type I and Type II functional responses to their prey. What about predators with Type III responses?

How do predators change population growth?

Predators are one of the factors contributing to death rates, and so if a species has any predators at all, predation is part of the logistic model.