What is the feminine form of GANDER?

Geese:
Male is a gander.
Female is a goose.
Young is a gosling.

Female is goose.
Male is gander.
Young is gosling.

In English there are no masculine or feminine forms. English uses gender specific nouns for male or female; for example:

The gender specific noun for a male is a gander.

The gender specific noun for a female is a goose or a hen.

Goose terminology

A gosling is a baby goose.

A female is a goose or hen

A male is a gander

A group on the ground is a gaggle

A formation in the sky is a wedge or skein