David K. Ellifrit/Center for Whale Research, permit number: NMFS 21238.
- Southern Resident killer whales take care of their sons much longer than their daughters.
- Scientists have observed them feeding their sons well into adulthood, an expert said.
- As food is scarce for these whales, that strategy may now be threatening their ability to survive.
Southern Resident killer whales look after their sons well into adulthood, and it may be threatening the population's ability to survive, according to a study published Wednesday.
Daughters find their independence early on in life, but moms continue caring for their sons and sharing food with them throughout their lives.