Well I think it depends on what exactly your hypothesis is.
In our case, we had reason to believe that during a trapping session the detection decreases from day 1 to day 3. Thus we only cared about the day of the trapping session.
If you think every day could be different and want to test that, then you could do the same thing I showed, but have a unique factor value for each day. You would need to figure out if that hypothesis makes sense to you.
An alternative that you might consider is thinking of covariates that would predict detection like temperature, precipitation, or day of the year (Julian day). Those might be easier to interpret than a unique value for each day of sampling.