After the presumed death of young orca J50, there are only 74 Southern Resident killer whales alive. But that number is misleading.

It may not sound like a lot, and it may not sound so dire to see the number 74. But that's how many Southern Resident orcas are left alive as young J50 remains missing and presumed dead by the Center of Whale Research.

The problem is 74 doesn't tell the full truth because the majority of Southern Resident orcas are not reproducing. It means the opportunity to have more births than deaths is dwindling.

There are nine reproductive females in J-Pod and only three produced viable calves in the recent decade. The pod now has three young females and seven young males. K-Pod only has one female reproducing.

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Take L-Pod for instance, there's really no whales that are reproductively capable, according to Center for Whale Research Founder Ken Balcomb.

"There's only about four females having babies in the last decade," said Balcomb.

Adding to that, 75 percent of the pregnancies are ending in miscarriage or death. Half of the babies in the "Baby Boom" have died.