Spring in Berner’s Bay

so much to discover and ponder!

Every year, exciting things happen in Berners Bay. Eulachon (a.k.a. hooligan) run into the rivers to spawn. Herring come in great shoals and often spawn on the rocky shoreline there. And, of course, hordes of their predators come to feast. Every year, also, a little group of kayaking friends tries to be there when all that show is going on. It’s a bit of a lottery: sometimes we find an almost empty bay; sometimes we hit it big-time. This year was a good one!

We got off the beach in Echo Cove by nine o’clock, in good paddling conditions. On the way up-bay, we saw several humpback whales, cruising around, frequently lunge-feeding. This was a good sign that there might be a show developing in the bay. A strange sight was a northern harrier being chased by a squad of gulls. Had it tried an on-the-water snatch, arousing their defensive reaction?

A snarling, writhing ball of dark fur resolved itself into two river otters as we passed. “Otter-wauling” seems to accompany the mating process in otters for some unexplained reason. Although otters mate in spring, the undeveloped embryo does not implant in the female’s uterus until fall, and the cubs are born the following spring. Delayed implantation is common among members of the weasel family.

Way back last fall, we rented the Forest Service cabin for the last weekend in April. Because there were six of us and the cabin is small, two of us chose to set up our tents near the cabin. Cosiness is nice, but there are limits…

Arriving at the cabin about noon, we had plenty of time for settling in and then doing a bit of exploring. Some of us hiked over to the waterfall to see if dippers live there (they do). Along the quasi-trail that squirms along just above the edge of the cliffy shoreline, we found the feathery remains of some predator’s lunch. A few yards farther one, there was another one. And then another. We puzzled over the identity of the feathered prey—black and white, yes, but there are many black and white birds. Then we found yet another scattering of feathers, with some bones and a bill. Aha! These were the remains of a Common Murre. As we scrambled along, eventually we found nine of ten leftovers from the lunch of the predator(s)—probably eagles. So we called this route Murre-der Row.

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Field sketch page documenting Murre-der evidence. Illustration by Katherine Hocker

That evening, things were popping right in front of the cabin. Bonaparte’s Gulls were diving for tiny fish near the shore—probably catching young pink salmon that had hatched recently. A shoal of herring arrived and predators soon followed. Sea lions, mostly juveniles, were having a grand time, often porpoising in pursuit of their dinner. Some invisible underwater predator, presumably a big fish such as a king salmon, was terrorizing the herring too. Panicked herring were leaping every-which-way out of the water. Some of them stranded themselves, or stunned themselves, on the shoreline rocks. The local raven took full advantage of these freebies, making regular trips, fully loaded with fat herring, from the rocks to a particular place (presumably a nest) south of the cabin.

This same raven, or its mate, had earlier scavenged things from the outflow of the tiny stream by the cabin, where previous cabin users had dumped their garbage. Body parts of Dungeness crab still lay near the tideline, along with bits of cauliflower (!), which were wisely rejected.

As twilight crept in, we heard the song of our first Hermit Thrush. A fine ending to a good day.

Otters

they are surprisingly social

A week or two ago, I enjoyed watching a young otter, grooming and snacking, on the banks of my home pond. The next morning, when I peered out my windows, it was clear that the otter had come back, leaving a furrow in the snow, across the frozen pond, under my front-entry deck, and around the house. A few days later, it was back, scouting around the house and garden and checking out the pond, leaving a new furrow in the snow. Perhaps it has a regular (but temporary) route it follows, revisiting places where foraging has been successful in the past.

I’m guessing that this individual is a member of the family we often saw in the Dredge Lake area last fall. There were four big offspring with their mother. The young ones often stay with their mother into the winter and then disperse to live on their own. Dispersal distances are sometimes quite long, averaging almost forty miles for females in one Alaskan population (and slightly less for males).

otter-2-jos
Photo by Jos Bakker

Young otters continue to grow for several years, although they are said to be sexually mature when two years old. But males may not be “accomplished breeders” until they are five to seven years old, according to the literature. Mating usually occurs in spring in Alaska, but otters, like other members of the weasel family, have delayed implantation of the embryo. This means that the early embryo floats around in the female’s uterus for many months in a state of arrested development. Eventually, the embryo attaches to the uterus; active development begins and takes about two months.

The otters I’ve seen here in Southeast have been solitary or clearly a family group of mother and offspring. So I was very surprised to read that otters can be highly social. Males sometimes form long-term groups that forage together, perhaps breaking up in the breeding season when males go looking for mates, but then re-gathering for the rest of the year, and even staying together for several years. Nonbreeding females may join such groups. Occasionally a weaned offspring delays dispersal, staying home and helping the mother with the next litter.

As I skied around in the Dredge Lake area recently, I saw a long, brown shape poking around under the edge of the ice near a patch of open water. The otter emerged and foraged in the shallows until it noticed me, standing stock still on the trail. Then it bolted upstream. A bit later, I found a nice otter trail over the ice of one of the ponds, going out to a small area of running water and coming back toward the river. Hungry otters often cruise widely in their search for edibles. Almost any kind of meat is fair game for otters; although their mainstay is fish, they also eat mollusks, crabs, worms, frogs, and even occasional birds and small mammals.

Although their official common name is ‘river otter’, some folks call them ‘land otters’, perhaps to distinguish them from sea otters. Both common names are a bit misleading, because the versatile ‘river otters’ forage not only in rivers and streams but also on land and in the ocean. We often see them on rocky beaches when we are kayaking. I once watched an otter diving repeatedly down to a submerged bar between two islands; this was a banquet in salt water, apparently, because the otter brought up something edible on almost every dive.