Hi Jessica, I am curious: How frequent are your GPS fixes and for how many individuals do you have data?

In my opinion, an 8 month gap is too large to not somehow account for it.

If I understand you correctly, you were aiming have two years of data i.e. two summer/fall/winter and spring seasons, which means you were probably planning to account for inter-annual variability anyway. Does the gap affect all seasons in year 1 or only a subset? Could you not include individual and year (in addition to season) in your seasonal habitat and survival analysis to account for the gap/reduced sample size for some seasons?

Saskia Wischnewski as I currently am planning on defining the 4 seasons, the gap starts in mid-winter, and ends in mid-summer. You are right, I could just exclude the individual from the spring season, and use successful locations during portions of the winter and summer seasons.

Would annual estimates be biased?

Mhhh... I would omit all affected seasons (i.e. in your case winter, spring and summer) to avoid the bias as much as possible. After all, habitat use at the end of winter or the beginning of summer might not be reflective of the whole season.

How much gaps in the data/only having one year of data for some seasons for one of your individuals affects your results depends on number of individuals tracked (sample size) and the extend of you inter-annual/inter-individual variability in habitat use. How you minimize any potential bias depends on your question/hypothesis.

If in doubt, do the analysis twice with and without the incomplete data and see if it changes the results dramatically. It shouldn't.