I'm looking to carry out a study which will involve a pairwise choice comparison. I am aiming to identify any patterns of preference by wild individuals (measured by abundance) when presented with four different types of refuge. I will be conducting it in the form of pairwise choice comparisons, e.g.

R1 vs R2

R1 vs R3

R1 vs R4

R2 vs R3

R2 vs R4

R3 vs R4

There will be four replicates of each of the six pairs, (i.e. R1 vs R2 x 4, etc.), and I will survey each pair and their replicates 19 times over a set period.

So, hoping this makes sense, can anyone help me with getting my head round the appropriate statistical test to use to analyse this data? If anyone can go one further and also tell me if my current methodology has a sufficient sample size for the suggested test, that would be amazing. I'm concerned that the subsequent sampling (18 re-visits) is pseudoreplication....