The baby killer whale was first spotted Tuesday, and government whale observers confirmed the birth on Wednesday, The Seattle Post-Intelligencer reported. The calf is the fifth born to J14, also known as Samish, a 33-year-old female.

Orcas, or killer whales, are assigned identifiers that include a letter representing the pod and a number giving their rank within it.

The Puget Sound Orcas spend the summer. In late fall, they move out to sea and travel up and down the U.S. West Voast until late spring.

Numbers of Orcas in the sound dropped in recent years because of a decline in one of their main food sources, salmon, boat traffic and toxic pollutants. Those are especially dangerous because they build up in females' fat and are transmitted to their calves during gestation and nursing.

Experts say that J43 is lucky to be Samish's fifth calf because the mother has had "a chance to offload a lot of her toxins on the other calves," said Susan Berta, one of the founders of Orca Network.