Crowds of pinnipeds are returning to their rookeries on California beaches this time of year to give birth to their pups. The most common of those pinnipeds right now -- from San Luis Obispo northward -- are Pacific harbor seals and northern elephant seals.
Their rookeries aren't exactly private. There are even boardwalks stretching above some of them, where humans can actually witness seal mothers giving birth and nursing their newborn pups.
But that exciting proximity can come at a potentially deadly cost.
Harbor seal pups live on the beach for a couple of months while their mothers feed on fish in the ocean. From the water, mothers keep a watchful eye on their pups -- and if a pup's mom sees a human or a human's canine companion getting too close, she will abandon her pup.
Elephant seal pups are born unable to swim, and have to spend lots of time learning in shallow waters.
They may not learn properly if this crucial growth process is disrupted by beachgoers -- and that can spell doom for the pups and, in turn, the health of the entire herd.
Dr. Abby McClain, a veterinarian at the Northern California Marine Mammal Center in Sausalito, says pupping season typically brings an influx of starving newborn pups.
The Marine Mammal Center currently has more than 80 young patients.
McClain says many of them either became separated from their mothers during storms and washed ashore, or they were likely abandoned.
The number of the center's patients isn't unusually high for this time of year. What's more concerning to McClain is the high number of negative human and dog interactions over the past two years.
She says there were more than 100 such known encounters, way up from previous years. It puts the future of the statewide seal population at risk, she says.
McClain says people should enjoy their time observing seals but always keep their distance.
"If these negative encounters continue to increase, we are likely not going to be able to enjoy this for much longer.”
If you encounter a seal pup of any kind, McClain says to put a healthy distance between yourself and the pup.
As a guide, she says if you are taking photographs and do not have to use your camera zoom, you're too close.
So, that selfie with a seal -- no matter how tempting -- could cost the seal pup its life.
Photos of seals taken from a safe distance are appreciated by the Marine Mammal Center. They use them to keep track of strandings and to assess a potential rescue.
To report a marine mammal in California that appears ill, abandoned or in danger, call the 24-hour hotline: 415-289-7325.