Probability of Being Displaced

Hi all,

I'm trying to work out the probability of an animal being displaced from a resource at different life stages. For example there are five life stages from least dominant to most dominant. I would like to use some probability distribution to model the probability of the different life stages reaching the resource once one of the others is present.

So it´ll be a 'time until' distribution. Does anyone know which one is most suitable for my model.

I know this is a bit vague but I'm trying to get a start on this problem! Let me know if you'd like more details.