Thanks for checking that out. I was able to reproduce the problem and found the code used with 'hcov' had a bug for sessions with only females. I have put a new version at https://www.otago.ac.nz/density/zip/secr_4.3.2.zip (Windows binary) or https://www.otago.ac.nz/density/zip/secr_4.3.2.tar.gz (source). I hope this is the end of the problem, but of course let me know if it isn't.
Murray