Munida gregaria

Munida gregaria is a species of squat lobster found along the eastern seaboard of the South Island of New Zealand, around the southern coast of Tasmania and in a few locations around southern Tierra del Fuego. Its specific epithet ("gregaria") derives from its behaviour in the immature phase to form very large shoals or swarms of many tens of thousands of individuals in shallow coastal waters. This can result in mass strandings.