Ivermectin actually isn't an effective wormer. If they had lice or mites, it would kill those, but it's not good for worms. If you can get Safeguard, that's a good choice.
They came through :) Does her undercarriage seem to hang pretty low to the ground? That is an indication of gender. Like the goose on the right in this picture:
On the left is a gander and on the right is a goose.
Body language can help you sex her - does she walk around proudly with her nose up in the air, or does she walk around with her head more lowered? When you had two, was the other one always putting itself between her and anything that might be a threat, or was it the other way around, or did...
- Yes, you definitely should get another goose. She would follow around the ducks and hang out with them, but it's not the same. They really need to have a friend of their own species. I had a single goose for a little bit and she is much happier now that she has a mate of her own kind and goose...