November Morning

By Megan Isadore, Executive Director, River Otter Ecology Project
December 1, 2015

Teasing out social structure and behavior is an important part of our work. The way otters use their habitats, bring their young and interact with their prey species provide clues to what allows them to thrive in our watersheds, as well as to how they affect the animals around them. Here’s an account of a very special field day to bring you cheer on this Giving Tuesday. THANK YOU for supporting us and making our work for otters and their watersheds possible. Please donate if you can.

The Early Otter Gets the Bird
We arose at dawn and headed down the trail in a chilly breeze, very glad for our extra layers of long underwear, hats and gloves. Sunlight sparkled on the feisty swells in the lagoon, and we heard waves crashing at the shore. Deer grazed nearby, kites and red tailed hawks flew above, a raven sat on a fence post gnawing on a bird head. Quail called, their plaintive wild chi-caaaaaaa-go chi-caaaaaaa-gos alerting us to their flocks gleaning the fields. A ferruginous hawk flew over, and we thrilled to her glorious pale underwings.

We sought otters, and for a while there was no telltale ripple or bubble on the bright waters. Then there was….and two, three, no – four small sleek heads swirled to the surface, followed by long flexing bodies and muscular tails. The mother and her three youngsters, just a few months shy of their first birthday! They swam purposefully back the way we had come, and we followed them at a respectful distance. We stayed well behind, and some distance back from the shore, to avoid stalking. They paid no attention to us, but were intent on the flocks of hundreds of coots, mixed in with pied billed grebes, goldeneyes, mallards and various other ducks and shorebirds. 

Many people don’t realize that river otters actually eat quite a few water birds, especially in fall and winter along our coastal waterways. We find gull, coot, pied billed grebe and cormorant feathers in their scat on a regular basis from fall into winter. Because river otters are warm-blooded animals who spend quite a bit of their time in cold water, without the protection of the thick fat layer most marine mammals carry, they have high caloric needs to keep warm, and they hunt often. It takes just a couple of hours for a fish meal to go through their systems.

This day, the coots were spooked by our presence and took off in a flurry, then noticed the otters. Some flew one way, and some the other, some settled back onto the water and the otters took advantage of the confusion. When the feathers settled we saw two of the otters with a bird each, followed closely by the other two. One bird flapped, but was held tightly by the otter…the other appeared unmoving. All four otters swam directly to a quiet cove, and the larger juvenile dragged her still-flapping coot out of the water, then disappeared into the pennywort in the shallows. We snuck around them, staying far back from the bank, and crouched down to make ourselves inconspicuous. We were rewarded with superb viewing of the otter making very short work of the coot while the two other juveniles fished for themselves in the shallows, catching their own dinner.

When the pups are young, their mothers hunt for them, and bring prey to them in their dens. Once they’re old enough to learn to swim and fish, the mothers still catch fish for them, but also teach them how to dive and catch their own prey. River otters’ whiskers, or vibrissae, are extraordinarily sensitive, allowing them to hunt effectively in murky waters. They’re opportunistic carnivores, catching whatever fish, shellfish, insects, frogs, birds or small mammals they’re able to get.

It was interesting to note that the two fishing for themselves did not try to grab the coot from their sibling, though they nosed around him/her a bit while the feeding went on. One did collect a discarded wing and took it to a rock to eat. Meanwhile, the smallest otter stood on the bank and began to chirp rhythmically in the contact call we hear between families. A few minutes later we saw the mother, who had disappeared with her bird (possibly a grebe), swimming back across the cove. And then one of our favorite otter behaviors happened. Though they had been separated for only about 10 or 15 minutes, and the mother had been close by the whole time, a joyous reunion occurred, with mother and pup nosing, hugging and grunting the “happy otter” greeting. Another of the pups joined in, and the three rolled and nuzzled in the water. I truly love to see the affection otters show one another in their family groups.

At last, everyone fed and together, the four headed back toward one of their resting spots. It had clearly been a successful hunt. Full of fish and coot, the otters were ready to nap.