Conjoined gray whale calves_1
© Farah CastilloConjoined gray whale calves.
Scientists in Mexico's Laguna Ojo de Liebre, or Scammon's Lagoon, on Sunday discovered conjoined gray whale calves, and it could be the first documented case of Siamese twin gray whales.

Conjoined twins have occurred in other species, notably fin, sei and minke whales. However, an online search and a search of the database at the Natural History Museum of Los Angeles County did not reveal published instances of conjoined gray whale twins.

Conjoined gray whale calves_2
© Jesus Gomez
Unfortunately, the twins discovered in Scammon's Lagoon did not survive and most likely were miscarried. The the carcass is only about seven feet long, versus the normal 12 to 16 feet for newborn gray whales.

Alisa Schulman-Janiger, an American Cetacean Society researcher, pointed out that the twins were severely underdeveloped and wondered whether the birth or stillbirth might also have killed the mother.
Conjoined gray whale calves_3
© Grabriela Rodriguez
The twins' carcass has been collected for study.

The first and third images with this post were posted Sunday to the Guerrero Negro Verde Facebook page, with the translated statement, "Unfortunately, the specimen died. [Its] survival was very difficult." The middle image was posted to Facebook by Jesus Gomez.

Gray whales are arriving in Scammon's Lagoon and other lagoons along the Baja California peninsula, after a nearly 6,000-mile journey from Arctic home waters. They give birth during the southbound journey, or in the lagoons, and nurse their calves for several weeks before embarking on their northbound journey back to the Bering and Chukchi seas.


According to NOAA, the Pacific gray whale population numbers about 21,000.

Most calves are born during the last week of December and the first two weeks of January.