1) Detestable? Abomination? Way harsh! Actually, this list makes sense. All of these birds prey on living creatures. Most of them prey on animals such as rats, frogs, and insects. I can see how one might consider them detestable to eat for that reason.
2) Bats aren't birds but I don't fault them for not knowing that yet.
3) Mom, aren't you glad they didn't want to eat "the heron of any kind?" My Mom loves Herons.
4) And, for anyone who's curious what a hoopoe looks like (because I definitely was) here you go:

