On the water

a whale watch trip stirs up questions

I don’t get to go whale-watching very often, but when I do, I usually see something interesting and new questions frequently get stirred up.

One trip gave us a good view of humpback whales doing their locally famous bubble-net feeding. Most of us here have seen this behavior at one time or another, but somehow it has not become ‘old hat’. How does a group of whales decide which one will create the rising, circular curtain of bubbles that rings a school of little fish? How did they invent this foraging tactic in the first place? Did it really originate here, and get carried to Prince William Sound whales by a wandering Juneau whale? How do they coordinate the upward rush of several whales through the panicking fish and avoid crashing into each other?

Another trip brought a troop of Dall’s porpoises, cavorting around the bow of the ship. The group grew, as additional individuals came zooming in from who knows where. They played there for some time, to the great delight of all on board. Then they disappeared, apparently on some magical signal; suddenly they were simply gone, vanished out of sight. Why did they all gather by our ship? And why did they go?

Then, in early September, we watched a small pod of orcas cruise by Little Island, where hundreds of Steller’s sea lions, of all sizes, had hauled out. Even the few sea lions that happened to be in the water a few feet from their dry confreres on the beach did not seem to be alarmed at the orcas passing nearby. Mammal-eating orcas don’t use their sonar to find prey, because mammals can hear the beeps. So we thought that these must be a resident, fish-eating bunch of orcas, using their sonar to find fish and therefore no threat to the sea lions.

As the orcas went on down along Ralston Island, we learned that this was actually a group of transient, mammal-eating predators, identified by a known mark on one of them. Nevertheless, no prey was visible and they acted (to our eyes) as if they were hunting fish: sudden, brief changes of direction and quick dives. This led to the question of whether mammal-eating orcas might sometimes snack on fish as well.

Then a small band of juvenile sea lions came into view from the opposite direction, seemingly oblivious of the jinking-around orcas—until the two groups of animals were very close. Then the sea lions really freaked out, caught between the rocky shore and the orcas. Much frantic splashing and churning about! As the orcas placidly went on their way, the sea lions calmed down and swam toward Little Island. What was going on here? Mammal-eating, transient orcas with already full stomachs? Just fun and games for the orcas? Mistaken identification by the sea lions?

Later that same afternoon, we encountered a scattered group of humpbacks doing nothing very exciting. But alongside our boat there appeared a solitary sea lion with something in its teeth. That sizable something was tossed and thrashed about until it was just a rag (and a few loose bits for the attending gulls). Finally we got a closer look and saw tentacles with sucker discs, just before the whole thing disappeared down the gullet of the sea lion. The octopus was caught at depth of over four hundred feet, not a very deep dive for a sea lion.

Early September observations

bear behaviors, sleeping shorebirds, and a diligent squirrel

The numbers of sockeye in Steep Creek had declined markedly, but there were still enough that a female bear with two cubs was able to catch five of them in about thirty minutes. When I came upon them, mama and one cub were busily chowing down on a fresh sockeye, while cub number two was perched up in a big spruce. Pretty soon, mama went out and got another fish—it took her maybe three minutes—to share (somewhat grudgingly, it seemed) with the first cub.

Suddenly, we all heard a loud ruckus just down the trail, as two young bicyclists approached. Fortunately, a ranger was on duty in the area and the raucous disturbance was quelled. But the bears were agitated, and cub number two was sent up the tree to join number one. After a watchful period, the female went back to fishing and caught three more fish in less than twenty minutes, but she didn’t share them.

Another pleasing bear observation: one day I drove up Riverside Drive, with no other vehicles in sight. Out of the brush on one side of the road popped a young bear. It looked both ways, saw me coming, and stopped. I stopped too. Then the bear took another look and rambled safely across the road. A street-wise bruin!

The Crow Point trail near the Boy Scout camp was littered with washed-up, pecked-over chum carcasses. I salvaged some nice clean vertebrae that still had all the ribs and dorsal spines attached: these were useful to me for clarifying a few long-standing puzzles of comparative anatomy—comparing the spinal columns of deer, bears, whales, and whatever else I can get my hands on.

Out on the sandy beaches, I found five dowitchers, all sleeping, with long bills tucked over their shoulders into their feathers. Some were standing on two legs, some on one leg. I was amused to see that as the tide came in, the one-legged individuals just hopped a few steps up-beach without bothering to lower the second leg—which of course was fully functional but resting comfortably up in the belly feathers. I’m not sure the birds even came fully awake—they seemed to go right back to sleep.

Signs of autumn were everywhere: gold leaves of mayflower, orange and red leaves of fireweed, all-shades-of-red leaves of highbush cranberry. Bands of migrating warblers were on the move, searching among the leaves for insects to fuel their southward journey. Mixed flocks of Lincoln’s sparrows and savanna sparrows rustled about in the brush. When I got back to my car, I fund a woolly-bear caterpillar crawling up a rear tire. I suggested to it that a wheel well was probably not a good place to pupate and assisted its transfer to a more productive spot.

tussock-moth-with-spots-2
Woolly bear caterpillar

Back home, I glanced out a window and saw a red squirrel trying to haul a thick, four-inch-long, white cylinder (maybe a mushroom stem) up a tree. The squirrel was having a tough time with this object, which often seemed to crumble or break, so the squirrel lost its tooth-hold. Somehow, the squirrel always managed to catch the thing when it started to fall, but progress up the tree was slow, irregular, and arduous. But the object got shorter with every attempt to haul it up to the next level; by the time the hard-working squirrel was out of sight, its prize was only about an inch long.

The annual Juneau Symphony whale-watching cruise was a treat: Great food, lovely string quartet, good conversations, and best of all, spectacular whale-watching. Several humpback whales were busy in the area just south of North Pass. All of them were lunge-feeding—making shallow dives and surfacing on their sides with mouths agape as they surged forward. A group of three whales seemed to collaborate; they came up side by side, so close together that it was hard to sort out which jaw belonged to whom. We saw an occasional pectoral fin waving, or half a fluke emerging. This activity went on a good long while; I had never seen such prolonged, concerted lunge-feeding before. We could not identify the prey that was so assiduously sought, but we did not see small fish jumping off to the side in efforts to elude the giant maws (as we often see when the whales feed on schools of small fish), so perhaps krill were the big attraction for the hunters.

Winter to spring

diverse sightings in a cruel (?) month

A poet wrote “If winter comes, can spring be far behind?” For Juneau in 2013, the answer is Yes! We’ve had, I think, three big snowstorms in April. Another poet wrote: “April is the cruelest month…” and, this year (so far!), that seems appropriate (with apologies to said poets for taking their lines quite out of context! Also to my long-gone eleventh-grade English teacher, who would be rolling her eyes and shaking her head, because the lines floated into my head, out of context, but not the poets; I had to look ‘em up to refresh my so-called memory. Sorry, Miss Dahl!).

The snow seems likely to bring temporary hardship to many creatures. The nesting hummingbird is sitting tight but no doubt having a hard time finding enough food for herself. The ducks on my pond are swimming through thick slush. Juncos, which typically forage on the ground, are driven to visit the seed feeders hanging over the pond; they cling with some difficulty to perches made for smaller birds. Mountain goats may stay at low elevations longer than usual, because the snow is too deep in their alpine haunts, and any newborn kids become more vulnerable to bear predation than they would be in the alpine zone. Will the early blueberry flowers get pollinated if the bumblebees are obliged to retreat to their nests?

But beautiful it is; as the annual Audubon cruise to Berners Bay set out in a snowstorm, we told ourselves that there is no place more beautiful than Juneau.

The spring run of eulachon (hooligan) in the rivers of Berners Bay had not yet begun, and there were no signs of herring spawning. But there were obviously forage fish in the bay, because their marine predators were busy. Tightly packed squads of Steller sea lions splashed and dove in unison, chasing some kind of small fish, or rafted up to rest in between foraging forays. A rocky reef was lined with bald eagles, with harbor seals scattered around just offshore. We saw humpback whales doing something that most of us had not seen before: five or six whales were foraging together, shoulder to shoulder in a tight bunch, often making short dives simultaneously. Some lone humpbacks foraging elsewhere in the bay came and joined in. My guess is that there were several small schools of forage fish in the bay, as a preamble to the big spawning events, and the predators concentrated their efforts because the prey had a patchy distribution.

Along with the usual assortment of gulls and sea ducks, we saw yellow-billed loons, which commonly winter along the shores of the northeastern Pacific. They look a lot like common loons and are indeed closely related, but they have a pale, slightly up-tilted, bill. These birds would be staging for a northward migration to the Arctic tundra where they nest, probably about the middle of June. They have to wait for the tundra lakes to thaw, so they can hunt for fish and various invertebrates; if they go north before leads open in the ice, many would die. Breeding pairs get together on the nesting grounds, and each female commonly lays two eggs that hatch around midJuly. It takes about three years for the young birds to mature and find their own mates.

yellow-billed-loon-winter-plumage-by-bob-armstrong
Yellow-billed loon, winter plumage. Photo by Bob Armstrong

There are reportedly fewer than about three thousand of these loons in Alaska. Their populations may be limited by the availability of suitable habitat—they need lakes with early ice-out, protected shorelines for nest sites, stable water levels so the nests don’t get flooded, and clear, shallow waters for foraging. They also may have to compete with other loons for suitable habitat.

Another wintry foray in April took us on snowshoes up the forested route to Cropley Lake. Among the interesting observations was a well-gnawed tree where a porcupine had found dinner. Much of the bark was gone. Porcupines feed on the inner bark and commonly reject the tough outer bark. The unusual thing was a deep, very tidy, circular mat of outer-bark chips closely packed at the base of the tree. We’ve seen lots of porcupine-chewed tree but had never seen (or ?noticed) how the chips piled up so neatly. We also found a little hemlock tree that had contorted itself into a full circle in its struggle to reach the light. Never give up!

Visiting Benjamin and North Islands

so much to discover!

By sheer good luck, our little kayak excursion to Benjamin and North islands happened to coincide with the only three consecutive days of sunshine in late-mid July. Sometimes happiness is sun, flat water, good company, and no pesky bugs. Really! No bugs!

There were three of us, all taking much pleasure in poking around on shores and in forest, just looking to see what we could see. And there was plenty for curious naturalists to find and contemplate.

Humpback whales were cruising around on all sides, and the whoosh of their breathing was a frequent backdrop. Sometimes there was a honking sound along with the breath, and we wondered if that was some kind of communication or if it was inadvertent, like a snore. A small group of juvenile sea lions attended us, popping up in close-packed unison on one side and then on the other, staring and snorting, apparently very curious. There was only one sea lion on the traditional haulout rock; it looked rather thin and unwell. A little pod of orcas foraged around a rocky point, and we were pleased to see two very small babies, along with two females and a ‘teenager’.

guillemot
Pigeon guillemot. Photo by Katherine Hocker

Adult pigeon guillemots were common, floating and diving, and making short flights that showed off their flashy red feet. We saw no juveniles, however, so the chicks were presumably still lurking in their cliff-crevice nests. A few marbled murrelets, including one juvenile, whistled and dove, and we also tentatively identified an ancient murrelet.

Pink salmon were jumping, and an unwary pink was lugged by a parent eagle to a nest, where noisy nestlings expressed their appreciation. Another eagle caught a large, unidentified fish, breast-stroked with it to a rock, stood on the still-flopping fish for a while, and eventually toted it off into the forest.

Choruses of shrieking oystercatchers indicated their frequent displeasure at some disturbance—by others of the same species, or by an overhead eagle, or whatever. One pair of oystercatchers dive-bombed a rock-perched eagle, bedeviling it until it gave up and retreated to the trees. Another pair of oystercatchers guarded two big, fuzzy chicks that made themselves ‘invisible’ by creeping in between shoreside boulders.

A rocky ledge held a crowd of gulls of various sorts, among which we spotted several black-legged kittiwakes, perhaps wandering over from Glacier Bay. Their short, black legs and long, black-tipped wings made them readily distinguishable from the ordinary gulls. Scattered along the mussel beds we saw several black turnstones, already headed south, apparently, and a lesser yellowlegs. Squadrons of harlequin ducks scuttled along the rocky shores, getting away from us as fast as possible without flying. Most of these were in female plumage and might have been some of this year’s young.

Patches of bright yellow-green seaweed caught our eye; they were especially vivid when seen through sunglasses. These turned out to be ‘sea-sacs’, hollow, finger-like algae at about the mid intertidal level. We later learned that, although this species is technically a red alga, it turns eye-smiting yellow-green when mature. Water oozes in and out of a small hole at the tip. Sometimes amphipods chew holes at one end of the tube and crawl into a ready-made protective house.

We hauled out on a beach for a snack and a stretch, and amused ourselves for a while by sorting pebbles. Here is a pile of the pretty-colored ones, or the super-smooth ones, or the ones with especially nice patterns or shapes. Just like kindergartners! But it got too hot in the sun–even the stones were distinctly hot to the touch—so we retreated to our boats and to more mature considerations, such as Should we have afternoon tea now or later?

Our camp was in a well-used site above a wide beach. Considering how much use this place gets, there was very little trash left lying about; we only filled about half of a big, yellow litter bag. However, there are limits to what we’ll pick up, and we were sorry to see that some recent campers clearly had no idea about proper camp sanitation and courtesy to subsequent campers.

Among the found objects on the beach was part of the well-cleaned head of a fish—probably a flatfish of some sort. Only a lower jaw and some flat plates were still linked together, and the jaw had several rows of small, curved teeth and a little bony spur at the front end. All three of us are profoundly ignorant about the functional anatomy of fishes, but we enjoyed our small deductive exercise in arriving at a guess that it came from a halibut.

Perhaps it doesn’t take much to engage the attentions of curious-minded folks! But what fun!