Newest cougar cubs in Santa Monica Mountains, P-59 and P-60, are ready for their closeups

Two new mountain lion cubs have been discovered in the Santa Monica Mountains, the latest offspring of a frisky male whose mating habits reveal a troubling pattern for wildlife in the area, the National Park Service said Tuesday.

P-59 and P-60 are a brother and sister who were located by Park Service and California Department of Fish and Wildlife biologists earlier this month in the central portion of the range, officials said.

The cubs’ mother is 2-year-old P-53, the youngest female in the Park Service’s wild animal study in the Santa Monica Mountains. This is P-53’s first litter and her age falls within the normal breeding range for her species, the Park Service said.

But it’s the mountain lion who mated with P-53 that poses a long-term concern for the health of the cougar population, the Park Service said. Officials believe the father of the cubs is P-12, who also mated with P-53’s mother, P-23, and P-23’s mother, P-19, and P-19’s mother, P-13.

“If P-12 is in fact these kittens’ father, that also means he’s their grandfather, their great-grandfather and their great-great-grandfather,” Jeff Sikich, a biologist with Santa Monica Mountains, said in a statement. “Inbreeding to this degree really highlights the need for providing safe passage across the 101 Freeway so new mountain lions can enter the population and breed.”

P-12 is the first mountain lion believed to have crossed into the Santa Monica Mountains from the north and brought with him something of a “genetic rescue” because of all the breeding that occurred once he arrived, the Park Service said.

Some argue that a wildlife crossing needs to be built over U.S. Highway 101 so other mountain lions can reach the range unhindered and increase genetic diversity in the population.

“P-12’s arrival ushered in a new era, essentially becoming the new king of the mountains” as the prior dominant male’s genetic line dissipated, the agency said online.

DNA tests will confirm whether P-12 is indeed the father of P-59 and P-60, the Park Service said. Experts believe he is the father and P-53 is the mother because of their behavior in the months leading up to the litter’s birth.

Residents in April reported hearing mountain lion activity near their property at about the same time as P-12 and P-53 were believed to be in the area. Since female mountain lions gestate for 90 days, park employees tracked P-53’s movements and noted she was nesting for longer periods than normal.

The Park Service has been studying the big cats in and around the Santa Monica Mountains since 1996 to determine how they can survive in an increasingly fragmented and urbanized environment.

joseph.serna@latimes.com

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