Year-round plasma steroid hormone profiles and the reproductive ecology of gopher tortoises (Gopherus polyphemus) at the southernmost edge of their range.

•The first year-round sex hormone profiles for wild gopher tortoises.•Male testosterone is elevated from September to December, and in June.•Female testosterone and estradiol are elevated from August to February.•Female progesterone increases in November and December to a peak in March.•Hormone profiles suggest an extended breeding season in populations below the freeze line.