Thanks to Sierra for this:

When Elephant Seals Become Ocean Researchers

Marine mammals unlock the secrets of climate and the Arctic

By Kate Golden

Illustrations by Masha Foya

ON A FEBRUARY MORNING at Año Nuevo Reserve on the coast of Northern California, hundreds of gray-brown elephant seals lay strewn, lumplike, all over the beach. It was hard to hear anything over the honks and shrieks of status jockeying and sex dramas. The north wind gusted to 35 knots and blew a river of fine sand into everyone’s faces. At a dense seal cluster near the water, researchers and students from the University of California, Santa Cruz, knelt over an 815-pound female whose stern had been labeled “X1” with Clairol bleach.

X1 was everyone’s least favorite seal because she had a penchant for abandoning her pup to chase researchers. But she was zoned out for the time being, sedated for the hour they needed to sample her tissue, snip a whisker, swab her butt, and glue little boxes to her.

Over the past month, X1 had birthed, fattened, and weaned her pup, all without eating or drinking a thing, as per the seal usual. Then she had gone into estrus and probably mated, though it could be months before she implanted the embryo to make a pup. Having completed these shore to-dos, she would soon pop off to the Pacific for a solo trip.

“Heads up!” UC Santa Cruz distinguished biology professor Daniel Costa called out from the sidelines. Costa has run the seal research lab for decades and directs the university’s Institute of Marine Sciences. Today he was mainly acting as guide and bouncer. A young male, weighing about a ton, was galumphing toward them. One woman jumped up like a matador to brandish a bright-red scrap of tarp in the face of this aggrieved seal. He backed down. No one else in the X1 huddle looked up. They had a lot of work to do.

About three hours later, X1 woke up and waddled out to sea, joining an internet of animals—a network of seals across the planet that are sending us a constant stream of intelligence on the ocean.THE FEMALE ELEPHANT SEAL is an ideal data collector. (Males have a persnickety physiological reaction to injections that makes them more difficult to sedate.) Unlike some other species of seals, elephant seals don’t have to be caught, because they don’t give a flying fish about humans and because they are loyal to their natal beaches, where they mostly lie around and bark at other seals. Every year, they undergo a “catastrophic” molt, shedding their outer skin and fur all at once, which gives the monitoring equipment that researchers were gluing to them this morning a humane natural expiration date…

Read the whole article here.