1 "qui semblaient occupés à transporter de la nourriture jusqu'à leur terrier". Why not "leurs terriers"? The English text is "their burrows", i e in plural.
2. "Elles sont restées à les regarder une dizaine de minutes". The first time I worked through this translation excercise I used "observer" as a translation of "observe", but this was flagged and not given as an alternative. Thus, in the second time around I used "regarder", but this time "observer" was the correct translation and "regarder" was not given as an alternative. I cannot be wrong both times🤔.