UO Second Age

i was running through delucia passage and found it it looks like a eagle but red and ive never seen it before was wondering if it is era accurate or not it does fire damage (like frost in ice)

Im not sure if this is the right forum board for this but i wanted to know if nightmares spawn only in the following locations.

1:East of Delucia
2:Oasis
3:Cyclops Valley

Thanks