Monk Seal Monday #58: Monk Seals and Hagfish.

Like we’ve shared before, one of the most crucial times of a monk seal’s life are those first weeks after weaning. No longer fed by their mother, weaners must discover on their own what’s edible and what’s not. Sometimes that involves ingesting some marine organism not typical of a monk seal’s diet, say a sea cucumber. Considered “generalists” by scientists, adult monk seals forage on the ocean floor, using their strong necks to flip over rocks at average depths of 200 feet and deeper, dieting on octopus, eel, flat fish, lobster, and squid.

But not weaners. For the first few months after weaning, they stick close to shore, discovering what’s plentiful and easy to catch. Like sea cucumbers.

Kauai’s newest weaner, RL52, is adjusting to life as a monk seal. Here, he sports sea cucumber goo on his whiskers. This is very typical of young weaners.

Photo credit: V. Bloy

Unfortunately, a young monk seal’s edible explorations also include some unsavory things like this plastic hagfish cone.

Photo credit: V. Bloy

Photo credit: V. Bloy

Photo credit: V. Bloy

While RL52 didn’t run into any serious trouble this time, other weaners haven’t been so lucky. A few years ago, a young seal hauled out with a plastic ring around his muzzle. That same year, another youngster hauled out with a decaying plastic water bottle around his nose. A weaner in 2017 was found rolling in a wad of monofilament fishing line.

Here are some more photos of RL52 interacting with the plastic cone.

Photo credit: V. Bloy

Photo credit: V. Bloy

Photo credit: V. Bloy

Photo credit: V. Bloy

Lucky for RL52, one of our intrepid volunteers waited for him to abandon the hagfish cone; then, she retrieved it to dispose of it properly.

Here’s what remained of the cone.

Photo credit: V. Bloy

But just what is a hagfish cone and what is it used for?

We’ll start with a hagfish, often called a slime eel.

Turns out, hagfish are some interesting creatures. They’re fish but have no true fins. Resembling an eel with a long, narrow body, hagfish measure some 20 inches in length. Their tails flatten at the end like a paddle. Hagfish have brains but no spinal cords. Journalist Susan Scott wrote this great piece about hagfish. It’ll explain how they got their nickname, “slime eel.”

Hagfish are tricky characters to catch. The typical method starts with a sealed bait bucket. Then, these plastic cones are inserted into a hole in the bucket. The fish swim in but cannot get out.

Unfortunately, these cones often get detached from their bait buckets and wash up on the beach.

This coming Saturday, June 8, celebrates oceans–World Oceans Day. There are many ways to join the celebration. One appropriate way would be to join Surfrider Kauai in cleaning up a beach. Here’s a link to their calendar of beach clean-up events. Another would be to attend this children’s play at Kukui Grove.