Carrots and their wild relatives

a complex family of plants

Species of the carrot family (formerly named Umbelliferae, now Apiaceae) are still called umbellifers informally, referring to the structure of the flat-topped inflorescence, called an umbel. The nominate example of this family is the domestic carrot, which typically has a thick, straight, tapered taproot containing of about 15% carbohydrates, some vitamins and minerals, and a lot of water (according to one source). Carrots were originally domesticated in Asia, over a thousand years ago. Parsley, parsnip, and celery are other familiar members of the family. They have many wild relatives, of which perhaps seven genera are said to occur in the Juneau area.

The roots of these species are sometimes described as taproots and sometimes as clusters of fleshy roots; and sometimes the same species is described has having both kinds of root systems. Frustrated by the vagueness and possibly conflicting descriptions, I dug up a few specimens of four fairly common species to see for myself. Because I don’t know how long or how vertical a root must be, in order to be called a taproot, here I will just mention there being a main root, if a thick one occurs at the base of the stem. Thick and fleshy roots, in general, are storage organs for these plants, a source of energy for growth and reproduction.

Out on local beaches and gravelly meadows, we find beach lovage (Ligusticum scoticum). The roots of beach lovage are a popular bear food, as seen recently in the meadow near the Boy Scout camp. In the big meadow at Eagle Beach this year, lovage plants had been common but were almost entirely demolished by hungry bears. The roots were gone, leaving a few reddish leaf stalks near the hole. Elsewhere in North America, other lovage species are sometimes called ‘bear-root’ in Native languages, reflecting harvesting by bears. My excavations indicated that lovage usually has a short (about an inch or two—just a little snack!) main root, bearing several thick, fleshy side roots, in total perhaps equivalent in size to a small-to-medium carrot.

Those side roots may be likely to break when a bear digs for the main root, leaving fragments that can regenerate; a big, carroty main root might not be able to do that, because the whole thing probably would be dug up. Various Native groups that harvest some of these carrot-family relatives take just the main root, leaving the side roots for future growth. Could it be that short main roots with storage in side roots are somehow an adaptation (in part) to the risks of being dug up—a way of surviving (via regenerating fragments) that’s not available to strictly single-main-rooted forms?

We have two species of Angelica: sea-coast angelica or seawatch (A. lucida) and, less commonly, kneeling angelica (A. genuflexa). Both are dug up by bears, which eat the roots and sometimes the lower stem and leaf stalks. My little excavations indicated that there is usually a short main root with some fleshy side roots.

Hemlock parsley (Conioselinum pacificum) that I excavated all had a short main root supporting a cluster of fleshy roots, but another local naturalist found one with a long main root. A year or two ago, there were many reports of bears digging up this plant in the Eagle Beach meadow. This year in the same part of the meadow, I found that, while bears had taken almost every lovage root in part of the meadow, some hemlock parsley was still standing there.

A field of hemlock parsley, shortly before bears demolished the plants. Photo by Doug Jones
Conioselinum root. Photo by Bob Armstrong

Cow parsnip (Heracleum lanatum) has a hefty, sometimes both fat and long, main root, sometimes with side roots, but I have not seen evidence of bears digging up this plant. I’ve seen the seeds in bear scats, where they eventually germinate quite well. In addition to domestic livestock, marmots, bears, deer, moose, and many other animals in other areas are known to eat the upper, vegetative and floral parts, which one report says provide a decent source of protein. Stems and leaves are reported to be a major food source for bears in Montana. However, I’ve not observed vertebrate use of this species here; other local naturalists have documented that the leaves are eaten by marmots; stems and leaves may be eaten occasionally by bears and rarely by mountain goats. That begs a question: why are there so few observations of wildlife use of this very common plant here?

The stems and leaves of sweet-cicely (Osmorhiza) are part of bear diets at least in some regions, but the two or three local species are not very common here and I’ve not seen signs of vertebrate usage.

Pacific water-parsley (Oenanthe sarmentosa) is suspected of being poisonous, largely by taxonomic association with highly toxic relatives. However, cattle are reported to eat the foliage without ill effects. I found no information about wildlife usage.

Cicuta douglasii (Douglas water-hemlock) is extremely poisonous to grazing livestock and probably bears and moose too, although I have found no reference to wildlife usage. The roots and base of stem are said to particularly toxic. (Note: this is not the same as the species called poison hemlock, Conium maculatum, which reportedly does not grow near Juneau.)

Humans eat many of these species, presumably avoiding the most toxic ones; however, some toxins are found in other carrot-relatives– Be careful of eating these species. Ligusticum roots and leaves have made good human food, although it has been used by certain Native cultures to poison fish. Heracleum flowering stems can be eaten, if peeled; but the juices of this plant contain furanocoumarins that on human skin may be activated by sunlight to produce nasty blisters. Angelica stems and leaf stalks are edible; Conioselinum roots are used by humans in some regions. Roots and leaves of Osmorhiza are said to be edible. Despite rumors of toxicity, Oenanthe roots and stems are eaten by people in some places.

Note: “hemlock” derives from old English words meaning straw or stalk and plant; in other words, a plant with hollow stems. That has nothing to do with our local tree of the same name! The hemlock tree got its name, supposedly, because of a perceived similarity of the smell of its crushed foliage to the smell of the poison hemlock plant.

Three vignettes

a portrait of the naturalist in her own element

— Worming my way through the throngs of tourists, who were jabbering in at least four languages, I finally could peer over shoulders and outstretched arms with attached cameras. And there they were, the objects of all this attention: a female black bear with three tiny cubs of the year. Both tourists and bears were well-behaved. The bears lolled about between the platform and Steep Creek, occasionally nibbling on a leftover bit of sockeye.

After a while, Mom got up and sauntered a few feet away, where she munched on some greens. Her salad. A bit later, she walked slowly into the creek and, in one quick rush, caught a salmon. Crunch, crunch, crunch. She took it back to the cubs, and that was the main course.

Then they all ambled off through the brush, appearing a few minutes later under the next viewing platform. There they all snuffled around in the low vegetation, picking nagoon berries. Even the cubs know what to look for. Dessert!

— Between the north end of Fifth Street in Douglas and the gravelly part of the Crow Hill Road lies a short trail. Access into and out or a steep little ravine is assisted by knotted ropes, providing a new experience and a small thrill for the youngsters with us.

A small distance along is an old concrete dam on Bear Creek. Thanks to the works of Earl Redman and Bob DeArmond, I found a little information about the dam and the creek in the State Historical Library. Bear Creek was once known as Mission Creek, because of a nearby Quaker mission (the missionaries sometimes had a hard time with the miners…but that is another story). The first record of activity on the creek was an 1882 water claim for mining use. In 1888, a short-lived mining claim saw some sluicing and tunneling action at the very end of the Treadwell orebody.

The concrete dam was built in 1934, to supply water to the town of Douglas. It no long backs up water and the little creek flows unimpeded through the base, but I failed to find out when it ceased to impound water. Judging from the vegetation in the valley, it was many years ago. The trail goes right along the top of the dam, with concrete railings on both sides. I’m sure there are folks in town who remember the history of this little dam, and I’d love to know more about it.

— The top of Thunder Mountain on a warm, sunny day in mid August was a floral paradise: Splendid arrays of the intensely blue broad-petaled gentian, whose flowers open and wait for visiting bees only in the sun; patches of the low-growing, single-flowered harebell, with its up-turned blue cup; tall monkshood with deep purple flowers; pink subalpine daisies; tall groundsels presenting their crowns of yellow sunbursts.

The ground-hugging dwarf willows were sending white tufts into the breeze, dispersing their seeds to parts unknown. Bog blueberries grew in mats over the thin soil, and some patches of them were loaded with ripe fruit.

There are spectacular views down to the glacier, the Valley, and the islands, to the bridge and on southward, and up to Heinzleman Ridge (and a possible mountain goat). The only birds were two ravens overhead, in leisurely conversation, and a few savanna sparrows (probably), dodging around in the low vegetation.

An interesting find was a single plate from the back of a chiton. A little more searching revealed a total of seven plates, weathering out of a pellet cast by some bird, perhaps a raven. So that’s one way the remains of intertidal creatures can end up in the alpine.

Lunchtime on top of Thunder has a lot to offer! Well worth the steep climb up and the long trek down through a string of pretty meadows, a scattered stand of yellow cedars, and through the woods and mud along an old pipeline to the East Glacier trail.

Roadside natural history

buzzing bumblebees and rototilling ravens

Cruise around Juneau on most any day, and chances are good that you’ll see something interesting or beautiful or both—things you can enjoy without driving into the ditch!). For instance, as pleasant relief from our customary shades of green and gray, there are the blue lupines and forget-me-nots and the creamy elderberry flowers.

At the end of May this year (a late, late spring), the shooting stars were finally coming into gorgeous bloom in the meadows between Freddie’s and the Lemon Creek junction. Look for swathes of pink flowers amid all the burgeoning greenery. And perhaps consider that these flowers, with their reflexed petals and all the reproductive parts hanging out in front, are pollinated by bumblebees. The bees land on the flower and buzz, so the pollen is shaken out onto the bees. Although the bees take some of the pollen home to feed their offspring, some of the pollen is transferred to the next shooting stars that the bees visit, and those flowers can then set seed.

You might see a gang of ravens rototilling a patch of mown grass. They dig up the old grass and the soil surface, leaving tufts of dry grass all around. There must be some kind of grub or worm that attracts all this attention. I’ve seen similar activity in other places, sometimes by crows. Robins too will rototill patches of moss. I’d love to know what they’re searching for!

rototilling-ravens-cropped-for-paper-David
Photo by David Bergeson

We often see deer and porcupines grazing along our roads, and sometimes flocks of siskins or crossbills come down to get grit or salt. But it’s bears that generate the most excitement from folks that are passing by. We can see roadside bears in several places, but possibly the most common area for bear-spotting is the ‘new’ Auke Bay by-pass.

Bears often come to forage on greens, such as dandelions, that grow alongside the roads, and they are fun to watch and photograph. However, there are two unfortunate side effects of this attraction. One is tha numerous cars may line up at the edge of the road, creating what is known as a ‘bear jam.’ This becomes a traffic hazard, with open car doors and people walking around, paying more attention to bears than to traffic.

The second unfortunate side effect is that over-eager photographers often crowd the bears, which can make the animals nervous. A nervous bear is unpredictable and may try to swat or charge a person that comes too close, perhaps leading to human injury. Injury to a human—even when the human brought the injury upon itself—sometimes results in (unfair) lethal action against the bear. Or possibly a nervous and annoyed bear might suddenly bolt across the highway, maybe with cubs in tow, and become a traffic casualty. Obviously, the bottom line is “Give the bears their space!”

Even whales can be seen from some of the highway pullouts (there are not many places in the world where you can do that!). When you see a humpback whale, consider that it feeds on small fish such are herring, which feed on krill and copepods (small invertebrates, which eat plankton)—and the phytoplankton (microscopic floating algae) get much of their nutrition from nutrients washed down in the streams from the forest, rocky peaks, and glaciers. In a sense, the rich foraging for whales that come here mostly in summer is provided, partially but ultimately, from the forests, muskegs, and glaciers.

Some roadside places offer good spots for watching ducks and gulls and maybe American dippers, as they forage and loaf around. Sheep Creek delta is one such place, for example, with pullouts right near the bridge.

July observations

an insectivorous squirrel, a piscivorous bear, jostling salmon, and ferny thoughts

–Out of the corner of my eye, I noticed a cottonwood branch twitching strangely. I looked up, expecting to see a bird. Instead, there was a red squirrel, bouncing out along the branch, stopping every so often. When it stopped, pieces of leaf fluttered down to the ground. A squirrel eating cottonwood leaves?? But why by-pass most of them, then? I reached for my binoculars and zoomed in.

I could see that some of the leaf pieces were yellow, not green. Then I could also see that the squirrel was not nibbling on leaf stems or leaf blades but rather it seem to be briefly manipulating each chosen leaf. Aha! Yellow leaf bits falling, squirrel picks only certain leaves…That squirrel was foraging for leaf rollers! This seems to be a good year for leaf roller moths, whose caterpillars use silk to bend leaf blades into protective tubes in which they live and feed. But there was little protection from this hungry squirrel, which cruised branch after branch, foraging all the way on juicy morsels of fat and protein.

Mine was not the only such observation: A naturalist friend observed another enterprising squirrel selecting rolled-up alder leaves. The squirrel noisily chewed open the leaf roll and ate the delicacy within, then moved on to more branches and more leaf rolls.

–It’s bear-watching season on Steep Creek near the visitor center, and one day I saw a yearling about twenty feet up in a cottonwood, in an odd pose with its rear end up and head down. Its hind feet were on one branch and its fore feet were on another, lower branch. Those front feet were deftly manipulating a salmon carcass, adeptly turning it first one way and then they other, occasionally flipping it over. The little bear eventually stripped that carcass down to spine and tail and let these remnants drop. Then it spent several minutes cleaning up its front paws and scampered up another fifteen feet to have a nap.

Young black bears usually separate from their mothers in their second summer. By then, they have learned a good deal about suitable foods and foraging, but they sometimes have a little trouble getting enough to eat. This little guy seemed to be doing just fine. However, it looks to be a rather poor year for berry crops, so it will be interesting to see how yearlings do this fall.

–While I was at Steep Creek one day, I watched the sockeye as the females were tail-flapping to disperse the sediments so they could lay their eggs in clean gravels, and the males were jockeying for position near nest-building females. Breeding males are deeper-backed than females, because they develop a slight hump on the back. The hump is probably a visual signal to other males, making its owner look big and hefty. Male pink salmon commonly develop such large humps that one of their other names is ‘humpy.’ But both sockeye and pinks can use the hump in the same way: when two males are side by side, contending for access to a female, the male with the taller hump leans over the smaller male in a literal put-down.

The first time I saw this behavior was while I was watching pink salmon coming into Sawmill Creek in Berners Bay. The male pinks in that creek seemed to have unusually tall humps, perhaps in part because the accessible part of the stream is quite short and flat, so a streamlined body is not so important. But it could also be partly because competition among males in that stream is, for whatever reason, particularly intense, making a big hump especially advantageous.

It was in Sawmill Creek that I watched a male pink that had such a huge hump that its body was shaped more like a dinner plate than a fish. This male would come closely alongside another male and lean that tall body over the less well-endowed male, forcing the smaller male to lie on its side until it could flap away. Since that time, I’ve seen this behavior several times, in sockeye as well as pinks. It seems to me that this is a form of physical domination, perhaps just short of a direct attack with toothy jaws.

–A friend and I are learning how to identify the local ferns. On a recent walk with that goal, my friend noticed a sizable brown caterpillar on a northern wood fern. The caterpillar was gnawing away at the fern frond, and nearby we saw several other chewed wood ferns. No other ferns on our walk showed signs of insect damage, but a botanist friend recalled seeing severe damage on lady fern on Admiralty Island a few years ago.

Most ecologists seem to agree that, in general, relatively few plant-eating insects specialize on ferns, and ferns get less damage from insects than flowering plants, even though there have been many millions of years for insects to evolve toward eating ferns. So how do ferns avoid heavy damage by insects? One suggestion is that ferns have general chemical defenses that reduce their value as food (just as tannins, for example, make many tree tissues hard to digest) that could be more difficult for insects to overcome than specific toxic defenses such as alkaloids; insects have evolved many specific detoxification mechanisms that allow them to utilize flowering plants that contain toxins.

Insects in August

nesting bees and willow galls

An observant friend was hiking up Mt Juneau one day in mid August. He was apparently the only one of the hiking group to notice a bumblebee that was digging a hole in the dirt at the side of the trail. A little farther along, he spotted another one, doing the same thing. I am envious, because this is something I’ve never seen here.

These bumblebees are queen bees that will hibernate in such holes over the winter. It seemed early to be thinking of hibernating, but perhaps our cold summer is sending them to bed before fall really arrives. Or perhaps they need to scout around for a while to find a suitable site. The queens have already been fertilized by the males, and these newly-fertilized queens are the only ones to live to next year: the males, the worker bees, and their queen-mother all die.

bumblebee-digging-nest
Bee digging nest

Next spring, the queens will emerge and forage on flower nectar and pollen. Each one will build a small nest of plant fibers and lay a few eggs, usually less than ten or so. Sometimes the mothers-to-be take over old mouse nests for rearing their broods. The queens provision the nest with pollen, on which the larvae feed. After roughly three weeks, the larvae become worker bees (sterile females). The queen makes several broods during the summer, each batch of short-lived workers helping to feed the next brood. Bumblebees live in much smaller colonies than honeybees; most nests are only two or three inches in diameter.

Both kinds of bees, however, are seriously declining, apparently because of virulent pathogens to which they have little resistance. The decline of the bee populations becomes a serious problem for humans, because so many of our fruits and vegetables are pollinated by bumblebees and honeybees. Think tomatoes and squashes, peas and beans; think apples and cherries, blueberries and blackberries and strawberries…the full list is very long indeed. If a solution to bee declines is not found, our diets will be much impoverished.

Out near the glacier, watchful rangers noticed a bear, which had just feasted on sockeye salmon, nipping off certain willow leaves. Each of the selected leaves had at least one and sometimes six or eight spherical lumps near the midrib. A few of the lumps were reddish on top, but most were pale green. Each one was about the size of the end of my finger.

These round lumps are galls, produced when an insect lays eggs on the plant. The insect’s activity, and that of the developing larva, manipulates the plant’s hormones in a way that induces the plant to divert some energy and materials to making the gall.

The galls are hollow, each inhabited by an insect larva that feeds on plant tissue inside the protective sphere. Dissection of a few galls by a helpful researcher at the Forestry Sciences Lab showed that the larvae are Hymenoptera—the order that includes bees and wasps. A little further research identified the gall as belonging to a kind of sawfly that specializes on willows. They are called sawflies because each female has a long ovipositor (egg-placer) with which she saws a hole in plant tissue to house the egg.

From the larva’s perspective, the gall provides not only a degree of protection from many (but not all) enemies, but also nutrition. The lining of the gall contains lower concentrations of several defensive chemicals than the outer part of the gall or the rest of the leaf.

From the willow’s perspective, the gall does relatively little harm to the plant. But male willows may be attacked more heavily than females by the galling insect—in at least one willow species, males provide more nutrients because they have more nitrogen, phosphorus, and potassium in the leaves than females. In some cases, the gallers prefer to use willows that grow most vigorously and have the longest shoots.

What might the bear be getting from its selective foraging? No one knows!

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.

Here and there in summer

alpine sights, body-checked by a grouse, some thoughts on bear viewing, and wildlife on the home front

–In early August I went up Gold Ridge in hopes of finding the big, blue, broad-petalled gentian in bloom. Being a rather impatient sort, I’d tried earlier, in July, with no luck. But on this warm, sunny day, there were a few in bloom and more with buds. Higher up on the trail, I didn’t spot any, and they probably bloom slightly later up there. However, the mission was successful on this day, and a search later in the month should find lots more.

broad-petaled-gentian-by-bob-1
Photo by Bob Armstrong

Even if there had been none of those beautiful gentians, the day was a good one. A mountain goat was silhouetted on the ridgeline; young marmots gamboled about, while a big adult lazed on a boulder. There were several bear scats along the trail and, of course, I could not resist inspecting at least the most recent one. It was full of salmonberry seeds, along with some vegetation fibers; because the salmonberries at this elevation were not yet ripe, I knew that this bear had been foraging down lower.

Bird life was not well-represented, however: a pair of curious ravens, a robin, and an invisible sparrow pip-pipping in the alder brush. It is always a little sad when the season of bird song is over for the year. Nary a grouse or ptarmigan to be seen, and I’d seen only one brood in July. Although apparently no official census has been conducted, they seem to be much scarcer on the ridge these days than they were a few years ago. Back in 2005, the area was opened to hunting, and it is very likely that hunting has reduced the grouse and ptarmigan populations. Many of those birds were habituated to people on the trails, and many of us thoroughly enjoyed seeing them and their chicks almost any time we ventured up the ridge. Shooting them would have been easy (and very unsporting). It seems that, for the sake of a few hunters, the pleasure of many observers was reduced.

–When the sockeye come in to Steep Creek, the bears can feast. This summer, the one we know as Nicky came down late, as usual, and she does not have cubs; she’s around eighteen years old and may be slowing down a little. The cubs of Bear 153 put on a good show one evening: swinging on the willows, tussling in the grass, getting startled by a big salmon thrashing upstream, tipping over the camera gear set (by permission) in the stream, cavorting in the shallows. I had dropped by, intending to stay just a few minutes, and ended up staying almost two hours.

The few times I have gone out there to bear-watch, the crowds have been quite well-behaved, not needing much guidance from the rangers about proper conduct in bear country. But with so many people visiting the area, someone (or someone’s dog) inevitably makes a wrong move that makes the mother bears nervous and concerned about their cubs’ safety. This is a time to be especially observant of bear body-language and to give the bears even more space than usual. These bears are quite used to people and normally behave extremely well; we can keep them that way, for all of us to enjoy, if we ourselves behave properly. A new guide to staying safe around bears, including some new information, is in the works; it will be available from ADFG.

–When we were in Bartlett Cove, Glacier Bay, one day in June, we stumbled upon a female grouse that clearly had chicks somewhere nearby. Standing on big rock, she clucked and fussed, even when we stood back to see what might emerge from the tall, dense beach grasses. I circled slowly back around her rock, hoping to see the chicks as they crossed a narrow path. Well! Mama did not like that one bit, and as I inched forward, she gave a body slam to my shoulder as she flew ahead, sounding the alarm. As far as that female was concerned, I had invaded her space and she was not going to stand for it! Then we saw the eight or so chicks—they had already crossed the path and were not close to the mother’s rock at all. Nice big chicks! They all took flight away from the presumed danger (us), followed by mama.

The next day, we managed to upset a pair of greater yellowlegs as we walked out into some extensive beach meadows. Both adults yelled and swooped at us, so we knew that there were chicks in the area. We never did see those chicks, well hidden in the tall grass, and the tumult subsided as soon as we moved out onto the open beach.

–My home pond was a happening place this summer. Four different broods of mallards made it a regular stop on their rounds through the neighborhood. First, there was a brood of ten ducklings (known as the Tens), then a brood of five (the Big Fives), a brood of eight (the Eights), and a later brood of five (the Little Fives). Seldom was there more than one brood on the pond at a time; if two broods happened to be there, one dominated the area under the hanging seed feeder. There was a nice rain of seeds falling from that feeder, as the juncos scratched among the loose seeds and the jays tipped the whole feeder off balance. This was manna from heaven! And not to be shared. The Eights would advance upon the Little Fives, pushing them into a corner of the pond, and go back to gobble up falling seeds. On another day, the roles would be reversed, the Little Fives winning the prize. The Big Fives sometimes charged at The Eights, relegating them to the far upper end of the pond, and went back to snarf up the seed rain.

Several broods of juncos (and their parents) grew fat on the seed offerings, and I watched the young ones gradually acquire their adult plumage. Bears wandered through but did not bother with the inaccessible feeder. I watched two predators with evil intentions about ‘my’ ducks, but they departed, still hungry. A roaming dog threatened one brood, and the mother duck led that dog a merry chase in her version of a broken-wing act: back and forth went dog and duck, the duck always just two or three feet ahead of the dog. She could have just flown away, but she was intent upon keeping that dog away from her young ones. The dog did not respond to orders from the shore, so eventually, my quick-thinking neighbor jumped in and grabbed the dog, and peace was restored.

The ecology of fear

the far-reaching effects of a universal emotion

What do animals do when they are frightened? They increase vigilance, scanning their surroundings with all available senses. Some ‘freeze’ in hopes that immobility renders them invisible. Some hide, in the best available cover. And some run. Any of those responses interferes with other necessary activities. In addition, the bodies of frightened animals respond to fear by increasing the production of stress hormones, and that increases the heart rate, the metabolic rate, and thus the expenditure of energy. Prolonged fear adds negative impacts on the immune system and reproductive physiology. All of these negative effects have consequences not only for individual animals but for their populations.

It doesn’t much matter if the cause of fear is a real threat or something merely perceived to be threatening. Failure to evade a threat bears a high cost and is often lethal, so even a perceived threat generally necessitates a reaction, just in case it is real. Play it safe, so you have a chance to play another day!

The importance of a perceived risk of predation was shown experimentally in a population of song sparrows in British Columbia. The perceived risk of predation was manipulated by using playbacks of predator calls, every few minutes all day and night long, four days on followed by four days off, throughout the entire nesting season. Some nests were exposed to various kinds of predator calls, such as hawk, owl, crow, and raccoon; as a control for the generation of extra noises, other nests were exposed to calls of non-predators (loon, goose, seal). Playbacks began well before female sparrows built their nests.

Nests were located before any eggs were laid. Direct predation on nests was prevented by netting and electric fencing, and video cameras recorded the entire nesting cycle.

The results for song sparrow reproduction were striking. Female sparrows exposed to predator calls built their nests in denser vegetation than those exposed to non-predator calls. Nests exposed to predator playbacks contained fewer eggs and hatching success was lower. Females with nests exposed to predator calls were jumpier, left the nest more often and stayed away longer, with the result that their chicks got chilled. Chicks in nests exposed to predator calls were fed less often by their parents, so they weighed less. As a consequence of chilling and fewer food deliveries, chick mortality was higher than in nests exposed to non-predator calls. The reproductive output of the population of sparrows with the perceived risk of predation was reduced by forty percent, compared that of the population without the perceived risk. It is likely that the ultimate difference between the two populations was even greater than forty percent, because deprivation during growth usually has continuing negative effects into adulthood.

Other studies have shown similar effects of perceived predation risk on the biology of other species, including elk and snowshoe hares. When hares were regularly exposed to the mere presence of a dog (a potential predator), their stress hormones increased. Females then produced smaller litters and the young hares (leverets) were unusually small and thin.

In addition, the risk of predation commonly affects where animals live and so can limit the availability of suitable habitat. For example, marmots avoid habitats where the detection of predators is impaired. Juvenile salmon and several other freshwater fishes avoid habitats pervaded by alarm cues from the bodies of dead or injured companions (although risk taking is likely to increase if the animals are not well fed). In the presence of tiger sharks near Australia, dugongs became wary and tended to move into different areas. Bears become less active in daytime and more active at night when close to roads and development. Wildlife abundance and activity is known to be lower near trails frequented by dogs.

By constraining habitat use, predation or risk of predation also affects foraging opportunities. For example, brown bears are dominant over black bears, which may avoid salmon streams visited frequently by brown bears; in such areas, black bears consume fewer salmon than where brown bears are scarce. Female bears, both black and brown, with cubs often avoid salmon-spawning areas frequented by male bears, to reduce the risk of infanticide; they have reduced intake of salmon and lighter-weight cubs as a result. For bears, fat mamas tend have bigger cubs and to be more successful in cub-rearing than thinner females, so risk avoidance has a cost (presumably a lower cost than with infanticide, however).

It is clear that predation risk and the perception of risk affect not only the behavior of individuals but also have probable consequences for animal populations, by affecting reproductive output. Furthermore, the consequences of fear may extend beyond the species that is directly exposed to the risk of predation, with cascading effects through the network on interacting species, although the magnitude of such effects probably varies greatly.

An example is found in invertebrates: when grasshoppers are stressed by the risk of predation by spiders, their body composition changes. Then, when the grasshoppers die and decompose, their altered chemistry slows the subsequent decomposition of the leaf litter. So materials are recycled more slowly, with other consequences still to be recorded.

A far more dramatic example was seen when elk in Yellowstone changed their patterns of habitat use to avoid wolves, moving uphill and losing much of the lush foraging near the streams. However, many other components of that ecosystem changed for the better. Vegetation near streams was no longer over-browsed; willows, aspens, cottonwoods recovered, which helped stabilize stream banks and improve fish habitat. When their major food plants (just mentioned) recovered, beavers moved back in, creating ponds that support fish, amphibians, and lots of insects on which other animals feed. Berry bushes also rebounded and were again able to produce good crops of berries, which feed bears, birds, and other animals. Good shrub cover in the streamside zones provides important nesting and foraging sites for songbirds, including Neotropical migrants. In short, dozens of species and the entire ecosystem benefit from a reduction of elk browsing in this area.

Little stories on the trail

a suspicious raven, a grumpy mother, and a stroll on the alluvial plain

Out on the wetlands in late September, I spotted a raven carrying a fish up into the conifers at the edge of the meadows. After eating part of the fish, the raven picked up the bedraggled remains and flew out to a mossy stump, where it cached its prey in a crevice. Then it hopped up to the top of the stump and looked carefully around in all directions for several minutes. It saw another raven, perched a hundred yards away, and me with my binoculars, and forthwith decided to move its catch far, far away. Sharing was not an option.

In mid October, the coho were getting ready to spawn in Steep Creek. One of the bear-watchers favorite bears, a cinnamon female called Nicky for the nick in her left ear, appeared with her chubby black cub. An expert fisher-bear, she caught a coho almost immediately and retired to the brush on the bank to eat it. Little cub wanted some too, and complained repeatedly, but mama was not about to share; she growled and moved the carcass away from every approach her offspring made. When she finally finished and the two bears wandered on upstream, a watching magpie came down to look for scraps.

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Nicky with a cub. Photo by Jos Bakker

About thirty minute later, upstream near the little waterfall, Nicky caught a second fish and carried it about forty yards away to eat it, calmly avoiding a cluster of people on the trail. Cubbie apparently managed to grab a chunk and eat all of it at some distance from mama. Nicky finished her catch, leaving only the dorsal fin. Then the little family moved on up the hill, leaving some very please bear-watchers behind.

The next day, she came through again, caught at least two coho, and added some northern ground cone to the meal. This time, she shared a little of the fish with the cub.

A little exploratory walk along Eagle River yielded several small mysteries. Invertebrates had left a variety of tracks in the mud. Worms, snails, slugs??—hard to know. But one long, thread-thin track ended at a tiny white spot less than a millimeter wide. My companion whipped out a hand lens to inspect the spot more closely and—oh my—it had a head end and it squirmed! This little maggot had travelled more than a foot, headed for who knows where. We released it to continue its trek.

Bears had been digging in many places, but the digs were several weeks old, so the tops of the dug-up plants had rotted beyond recognition. The remains of some of the dug-up roots had made new green shoots in preparation for next year, but slugs had eaten out many of them, leaving dry, brown bud sheaths behind. We were interested to find that the bear digs had exposed some inch-thick rhizomes (underground stems) that we traced back to lupine plants. This was the first we knew that lupines could spread in this way.

Strawberry plants are not common out there. But one, living dangerously at the edge of the overflow zone, had made an impressive runner, with the starts of about seven new plantlets at intervals. If they all survive the floods, there will be quite a family here.

On the bank of a slough, we noticed a few old bones poking out of the moss and mud. Looking more carefully, we eventually found several vertebrae, some ribs, and three leg bones. But whose?? A little forensic work made it likely that the bones had belonged to a long-dead bear.

Some other cool stuff: A flicker on the edge of a beach flew up into the nearby spruces; this seldom-seen woodpecker was probably on its way south. Some sedges with small, black spheres on the seed-head; they collapsed into dust at a touch and were probably the sporing bodies of a fungus. A Russula mushroom, whose broken, hollow stem revealed three dark, slender millipedes; what were they doing in there?

Every time we go out to find something of interest, we find at least two or three things! What fun.

 

Late August in Granite Basin

marmots, warblers, flowers and fruits… and a bear encounter

The day began under gray skies, but by midmorning the sun was lightening everyone’s mood. A sizable group of Parks and Rec hikers, including several visitors, headed up Perseverance Trail with plans to turn toward Granite Basin, a favorite destination of many locals.

Despite a few heavy rains in the past weeks, the trail was mostly clear of mud. A month before, the thick remnants of an old avalanche had extended over a piece of the trail and the creek. The snow pack did not melt away in the past two summers, so in July, we clambered over a heap of accumulated snow. But by late August, that old snow was gone, except for a small ledge.

The wrecks of alders and other shrubs littered the slope above the trail where the snow had lain, but many mutilated trees had produced a few late leaves. If they can get an earlier start next summer, before too long the slope may again support a cover of brush to make homes for warblers and sparrows.

Two marmots cuddled together on top of a big boulder, basking in the sun. Several clusters of mountain goats dotted Juneau Ridge. A few warblers flitted through the alders, stoking up their reserves for the coming migration. Copperbush still had a few flowers, but most of the flowers had made fruits that looked like tiny pumpkins with a handle (the remaining female part of the flower).

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Copperbush. Photo by Kerry Howard

There were quite a few ripe salmon berries—rather surprising in view of the many people who use this trail. Both red and yellow-orange fruits were fairly common. For the record, although there’s a myth that the red ones taste better than the yellow-orange ones, in fact the sugar content is equal. Blind taste tests with fully ripe berries showed that humans could not distinguish between the two colors by taste. We did a little berry-foraging for ourselves. So had a grouse or ptarmigan, because we found a scat in the trail was filled with salmonberry and blueberry seeds.

Wild flowers of several sorts still bloomed along the trail, and the native species of mountain ash bore its bright red fruits. A dipper searched along the edges of the pool at the entrance to basin and swam in the shallows after aquatic insects. The dippers’ customary nest site below the big waterfall had been under snow for the last two springs and was therefore unusable, but they may have nested in another site up on the back side of the basin.

Bears had wandered along the trail, leaving scats with seeds of devil’s club and vegetation fibers. Beside the trail was a wide swath of matted, broken stalks of false hellebore (a.k.a. corn lily), where bears had apparently gone after the basal parts of the plants. According to a hiker with extensive experience as a hunter, bears really do eat this plant. Although it is known to be very poisonous to humans, it’s not the only noxious (to us) plant that bears eat.

On the return trip down Perseverance Trail, several of us had a surprise. A female black bear with two cubs appeared in the trail. We stopped, and they ducked into the brush on one side of the trail. Unfortunately, that side was very close to the creek, with a steep drop-off, so there was no ready way for the bear family to distance themselves. Because we were in a group, we carefully passed by, speaking very politely as we did so. Mama sent the cubs currying up a tree and let us know her displeasure by rattling the bushes. That gave us a little adrenalin spike, for sure, but in reality, this bear was not being aggressive at all. She was just telling us in bear language to get lost, so she and her cubs could go on their placid way. So we did, and they did!