Placeholder goose

Placeholder Goose
"I was looking for an anti-swan, but none were to be found so I settled with the Placeholder Goose" - Wong Zhong Sun, talking about his new discovery

Placeholder Geese are waterfowl belonging to the tribe Anserini of family Anatidae. They are distantly related to swans and anti-swans, which they replace in a pseudecosystem if none are to be found. They are closely related to ducks and alarm-ducks

Etymology
Placeholder Geese are named because they are geese and because they replace swans and Anti-Swans if none are to be found.

Physical Peculiarities
Placeholder Geese lay fifty eggs a year.

Behaviour
As Placeholder Geese only exsist so that areas of the world that lack swans and anti-swans would have a substitute species instead of nothing, Placeholder Geese migrate in large zero-shaped formations of five to fifty members whenever a swan or Anti-Swan comes into the area.

Crusine
As swans and Anti-Swans are both much tastier than Placeholder Geese, Placeholder Geese are only eaten when there are none to be found. They are still very tasty.