A Rare Anomaly

This is a picture of a Canvasback nest with a runt egg next to a normal Can egg. Runt eggs (no known jargon) occur very rarely (perhaps 1 in 5,000 eggs) in most ducks.

They are not viable eggs, but an anomaly. Some piece of debris (yeah, not sure what) gets into the oviduct.

Then the detritus is treated like it was an ovulated yolk – it gets a coating of albumen and then shell and is laid. Never hatch.

Frank