Bryan Hamilton wrote:I've been working through some of the issues discussed on this thread and have a couple follow up questions.

1. With a "largish" p, abundance estimates from open population, JS models are more robust What constitutes a largish p?

Everything is better with high p. The answer to the question of 'how high is high enough for CJS abundance estimates to be useful' will depend on many things (including how you define useful). Simulation is your friend, here...

2. Heterogeneity in capture probability between uncaptured and recaptured individuals is likely, violating the assumption of equal capture probability. Does anyone know of a reference for this? I feel like I've come across something but can't recapture it.

Burnham, K. P., and W. S. Overton. 1978. Estimation of the size of a closed population when capture probabilities vary among animals. Biometrika 65:625–633.

Burnham, K. P., and W. S. Overton. 1979. Robust estimation of population size when capture probabilities vary among animals. Ecology 60:927–936.

Rosenberg, D. K., W. S. Overton, and R. G. Anthony. 1995. Estimation of animal abundance when capture probabilities are low and heterogeneous. Journal of Wildlife Management 59:252–261.

and, probably the most referenced cite:

Seber, G. A. F. 1982. The estimation of animal abundance and related parameters. Second edition. Arnold, London, United Kingdom.

For a nice review of such things,

Chao, A. 2001. An overview of closed capture-recapture models. Journal of Agricultural, Biological and Environmental Statistics 6:158–178.