Doubt about type of population

[jineth]

I have mark-recapture data from one population of tropical bats. I am interested in estimating abundance through three distinct areas of coffee agroecosystems in Colombia for six months. Also, I am interested in estimating population growth (λi), recapture probability (p) and survival (phi). I thought to take this group like a closed population, but I have a few number of recaptures. So, I´m not sure about how to assume this population. I´d like to know your opinion, when there are very few recaptures in a short sampling occasion where some bats died and born. What is it better? I should to assume that this population is closed or non-closured? What are you recommend me to use?

Any ideas are welcome!

Thanks!!

Jineth