ARTICLES

THE MYSTERY OF THE “MICE FROM THE SKY”

WHAT EXACTLY ARE LEMMINGS? HOW DO THEY LIVE? WHY DO THEY COMMIT MASS SUICIDE?

Sally Carrighar November 21 1959
ARTICLES

THE MYSTERY OF THE “MICE FROM THE SKY”

WHAT EXACTLY ARE LEMMINGS? HOW DO THEY LIVE? WHY DO THEY COMMIT MASS SUICIDE?

Sally Carrighar November 21 1959

THE MYSTERY OF THE “MICE FROM THE SKY”

WHAT EXACTLY ARE LEMMINGS? HOW DO THEY LIVE? WHY DO THEY COMMIT MASS SUICIDE?

To find her own answers to these fascinating puzzles this famed nature-writer spent an Arctic winter studying her own captive colony

Sally Carrighar

JUST ABOUT everyone knows that lemmings end their mysterious, short life cycle by mass suicide in the ocean — but no one knows exactly why. After studying these strange furry rodents in the far north all one winter I still don’t know exactly why either — but I have evolved a theory satisfying to me.

Few biologists have ever seen a lemming, even though they’re a species that determines the populations of many other species. When they march into the sea and drown, so few are left that one could believe they had become extinct. Then, in only three or four years, they reach fantastic density again.

During the time when so many are available a whole group of predators live on little else—and being so well fed. themselves breed at an abnormal rate. Other creatures like squirrels and hares, that ordinarily would be prey, are left alone and they too increase. Wolves ignore caribou when their hunger is satiated with lemmings.

The results extend a long way from the Arctic. Snowy owls thrive and multiply at the height of the lemmings' cycle. When they can

find no more, the owls’ hunger takes them south even into the Carolinas — and small birds and mammals there become the victims of owls they otherwise never would see.

Lemmings had aroused my curiosity for years. Some biologists are convinced the lemming hordes leave their birthplace because they exhaust the mosses and grass. Examinations of land over which they have passed, however, have proved that much nourishment still may be there.

For centuries the folklore of Europe has held that the migrating lemmings were seeking a former home on Atlantis, lands which existed in the miocene period and now are covered by parts of the Baltic and North Sea.

In every far-north country the primitive people call lemmings “mice from the sky.” The Eskimo word is “kay-loong-meu-tuk Several serious-minded Eskimos told me of seeing the lemmings come dow-n, “falling in bigger and bigger circles.” They described lemming tracks that “start where the lemmings land, w-ithout any footprints going to that place.”

continued on page 43

continued from page 26

“With food abundant in a warm burrow, they’d rushed into the cold salt waves. Why?”

I did not take the stories very seriously—until the day when I had a chance to see some of them for myself. It was early in April when Frank Ryan, the Eskimo postmaster at Unalakleet. told me that lemmings had landed that day on the end of the airsttip.

I hurried out. The black top was covered with less than an inch of new, light

snow_too shallow for any lemming to

tunnel under without thrusting up a ridge. And there indeed were the mysterious little trails just as the Eskimos had described them. In fifteen places a track began rather faintly, just as if the animal had come down and gently coasted onto the snow. I he tracks then continued more deeply and clearly, and led off to a clump of grass, where the lemmings evidently had burrowed among the roots.

I had been trying to find some live lemmings ever since 1 first came to Alaska. Unfortunately I had arrived during the low period of their cycle, and although my need for lemmings had been widely publicized, and many people were looking for them. I still had none.

When I saw the tracks out at the airfield. I thought my problem was solved. In the morning I’d dig up the grass roots and 1 felt certain I could find them. But by morning I had a fast-developing case of pneumonia and was bound for Nome and hospital on a mercy plane. When 1 returned a month later the lemmings had vanished.

l emming ghost towns

There was new hope, however. An air force major told me there w'ere “thousands" of lemmings on St. Lawrence Island. out in the Bering Sea within sight of Siberia. No commercial planes or ships made the trip that summer, but the air force and navy went out. and sometimes took civilians who had no other way of getting there. But both services refused my request for a ride. The authorities did not consider the catching of some "mice"—as they persisted in calling lemmings — important enough.

By the end of July I had given tip hope of reaching that island. I stopped at the Eskimo hamlet of Shishmaref for a final lemming hunt. The natives had reassuring answers to my questions about lemmings. Hundreds had been seen on the sand dunes—some within the last week. The pilot of my chartered plane left, promising to return in a few days, and I hired an Eskimo with a shovel.

The Eskimo, Foster Olanna. led me from the shore to some low mounds of sedges and cotton grass. Everywhere there were crisscross trails, used so recently that the new shoots of grass on the trails showed only as pale yellow tips. I he runways led to burrow entrances. Olanna started to dig, while I stood poised with a butterfly net to capture the lemmings.

The burrows were intricate passages up to a dozen feet long, all interconnected and with chambers opening off them. In each network one "room" was used exclusively for the animals’ droppings. We excavated a dozen little ghost towns —from which every resident had departed. To go where? Since this was a small island, the only direction the lemmings

could have taken was toward the sea— a migration of two hundred yards, but a death march.

Why?

The burrows looked comfortable. The runways led through food that was still

abundant. In what way were their lives made intolerable? What seemingly "unnatural" instinct overcame the instinct of self-preservation so that young and old took themselves out of this pleasant place to enter the cold salt waves? Now

more than ever 1 felt that somewhere 1 must find some live lemmings, study them, and hope they would reveal some hint of the curious impulse that destroyed them.

With my bags on the plane ready to

leave Shishmaref, I went for a short walk. A boat pulled up on the beach and a sailor jumped out. “Are you Sally Carrighar?” he asked. "We have come to take you to St. Lawrence Island.”

The Coast Guard cutler Clover was anchored offshore. The officers had heard about the woman who wanted lemmings so desperately. They had felt that the other services were a little ungallant, and had come to my aid.

There were signs of a gale as we rode out to the cutter. We headed north through waves as big as the cutter itself. It took us four days to travel the four hundred miles to the island. A radio message was sent ahead asking that some Eskimos be on hand to catch lemmings. A report came back that two or three dozen lemmings were caged and waiting in boxes on the beach.

We anchored in a turbulent channel. Nevertheless an Eskimo boat came alongside and was hoisted on deck. The captain said to the natives: “We have brought Sally Carrighar to your island to get some lemmings. We hear you have caught some and they're on the beach.”

“On the beach, all right,” said one of the Eskimos. “Only — not lemmings. Little animals, run every place on St. Lawrence Island. Just mice . . .”

Disappointment mingled with embarrassment as I looked around at the faces of all those men who had spent four days bringing me here on their ship.

Back at Nome, waiting for a taxi on the dock, I told my lemming troubles to Arnot Castel, a gusty little Frenchman who scampers around the Alaska coast picking up and delivering freight in a small boat.

“Let me take you to Barrow!” he urged. "You can always get lemmings at Barrow!”

I remembered the mountainous seas that have heaved up and dropped the Clover. What would Castel's boat do in such waters? I didn't care to find out. But I did decide that I would try Barrow first, next summer.

And at Barrow, the most northerly tip of Alaska, I found lemmings. On the endless tundra behind the town, again with an Eskimo and a shovel. I was digging out lemming burrow's without glimpsing a single occupant. Finally, however, I returned to the Eskimo home where I was boarding and heard the excited chattering of children. Eleven-yearold Joe Ningeok handed me a tin can. and I saw a ball of silky brown fur huddled in the bottom.

I put the small creature into the glassand-plywood cage I had brought, and watched with almost incredulous wonder this first of my lemmings. His fur was so long that it almost dragged when he walked. He had a blunt, upturned nose, ears almost lost in his fur. and a half-inch white tail, fully haired and arched up like a little husky's. He wagged it as he examined his new quarters, and had his say about all this with a sweet, plaintive chirring.

Spurred by Joe's reward, the children found five more lemmings. Six were all they were able to get, although they continued to hunt for the whole month I was there. And one had to be turned loose because he was so belligerent that he endangered the others. 1 could only hope fervently that my small colony would breed.

I had planned to stay in the Arctic only long enough to get some lemmings into a cage and on to a southbound plane. As their importance grew, however, I wondered whether the difficulty other naturalists had had in keeping lemmings alive could have been due to

taking the animals out of their own habitat. away from their own kinds of food, water, hours of daylight, barometric pressure, weather, relation to the magnetic pole — all those conditions may have more influence on animal lives than we know.

Once the thought was raised, there seemed only one thing to do: stay at Nome w'ith my lemmings.

Within a week I was living in a weather-worn house that was everything I did not w'ant—rooms too large and too many, too few conveniences, the whole house too dilapidated. The day I moved in I was too tired to go out to a restaurant. so I bought some eggs. Perhaps they had been in the store since the previous summer. Two exploded at the first tapping, and I broke eight before I found one that was edible. I decided I didn't want any dinner after all.

The moment was rather cheerless. To lighten il I put the eggs into a pan and took them out to a blue-eyed Siberian dog I had seen lying in front of the house. He rose, as all cautious animals do when approached, but he didn't come forward. I put the pan down and he lapped up the eggs.

A few' days later the dog—his name w'as Bobo—walked over and stood in

front of me at my open front door, his eyes even more intense than usual. An Eskimo who was working nearby called out: “1 think that dog smell your sky mice.” The sky mice. The priceless lemmings!

"No. Bobo—no!" I cried, and jumped up and went inside, closing the door behind me.

The lemmings soon w'ere proving every day that anyone who hopes to learn about the w'ay animals live in the wilds also needs to keep them for a time as captives. Out in the woods and fields everything happens so fast that what one observer may see is chancy, and many small, fascinating details may easily be missed.

On the vast expanse of the tundra, for example how could I have noted in my diary the following encounter between two of the six-inch creatures?

“Alliak. the first lemming found, was given a separate box yesterday. Today I put Eklasook. the one with the bright red-brown fur. with him. They ran to each other and caressed with their soft cushiony noses. I was gone an hour. When I came back Eklasook was asleep under some grass. Alliak was sitting up, grooming the fur on shoulders and head so that it stood on end and made his head look like a tiny lion's. Then he ran to Eklasook. They cuddled and slept. A pair?”

A cabinet maker in Nome constructed permanent quarters for my lemming colony, a glass-sided box to one end of which was attached the activity wheel I had brought from San Francisco. They ran on the wheel and I could measure the distance they covered each day. The cage was at eye level when I was reading or typing. I could look up and watch

their activities at close range. Into the cage we put soil, dried grass, moss and small pieces of driftwood, which lemmings nibble, no doubt for the salt, and on which they endlessly run and climb. I stored in an upstairs room quantities of natural materials for the winter months, several barrels of dried grass, a stock of driftwood sticks, a cubic yard of earth.

The new' vivarium had no more been set up than Eklasook produced the hoped-for increase in the colony. As soon as I put her into the new cage she be-

gan making a nest with frenzied urgency. She was extremely irritable, attacking the other lemmings and seeming half mad with tension. I moved her back into the old cage. Quickly she dug out a new burrow and carried quantities of nest material into it. To watch her work one would say she had only minutes to finish the job. Then she disappeared. By the next morning there were tiny squeaks from her cage. They continued all day.

Infant lemmings must be among the world’s most appealing creatures. When only an inch long they are fully furred

and proportioned. Eklasook had eight, the same number as her teats and a maximum litter. When they were two weeks old I made these notes:

“The small ones are tremendously busy digging burrows and every night rearranging them. They are also great climbers. They have many little peaceful encounters, the mild wrestling, nose to nose, typical of the adults . . . they all return to their mother frequently for reassurance. As an experiment I put two of the young in the cage of adults. They nosed up to the large lemmings in what

seemed an aggressive way but the adults treated them well.”

By late October, when I’d had the lemmings for three or four months, I thought I could detect clues in lemming characteristics that might explain why lemmings migrate, but nothing more by that time than the faintest suggestions. However enough had happened so that the project seemed well worth while, even though my personal living conditions grew worse with every week.

The autumn storms had begun, the crashing violence of the world’s worst w'eathcr. For a few nights I was afraid the house was haunted. Then I wished it would be. The empty rooms would have seemed more sociable if ghosts shared them. One night as I entered the house the rooms seemed larger, darker and lonelier than ever before. I sat down and took a long look at a certainty that kept turning into a question.

It concerned Bobo. The certainty was that I couldn't possibly have a dog in the same house with the lemmings. Yet I knew that I needed his company.

In the morning I went next door and discussed the matter with Bobo's owner who was soon returning south. "I would love to have Bobo if you have decided definitely you aren’t going to take him Outside. But I have to keep my lemmings alive because they are the reason I am here. Do you think Bobo would attack them?”

“On a trail he would,” she answered decisively.

We decided to try him in the house. We tied a rope to his collar, and both held it. When we entered the room and Bobo could see the lemmings behind the glass, he went nearly mad with excitement. He reared on his hind legs and tried to jump for the cage. With difficulty we led Bobo out. It was a sad day for all of us.

Next day I had to tell his owner: “I haven't been able to think of any way 1 could have Bobo.”

At those words Bobo rose. He stood motionless. Tension was gripping us all. Suddenly his self-confidence melted. Rushing forward, he shrank tight against me as a terrified child would. As a last resort the proud dog would appeal for protection; he sensed the emergency. I said: "Now, somehow, I'll have to take him.”

The solution to the lemming problem had presented itself: I would chain Bobo inside the house when he was at home. The chain would allow' him to come from the kitchen into the studio where I worked. There he would be close to the couch where I slept if at night he were lonely—but he could never go nearer than five feet to the lemmings.

Bobo scratched on my door at dusk. As he entered the kitchen I snapped the chain onto his collar. He did not move, but looked at me with such anger, such an expression of outrage, that my words of greeting failed in my throat.

I set out dishes of food and water. Bobo walked past them as if they—and I—didn't exist. He went into the studio,

IS YOUR SUBSCRIPTION DUE?

Subscribers receiving notice of the approaching expiration of their subscriptions are reminded of the necessity of sending in their renewal orders promptly.

The demand for copies to fill new orders is so great that we cannot guarantee the mailing of even a single issue beyond the period covered by your subscription. To avoid disappointment, your renewal order should be mailed to us promptly when you receive the "expiration” notice.

dragging the chain. Amazingly, he was ignoring the lemmings. He had not even glanced their way. The evening grew late. I dreaded to switch off the lights. In a kind of despairing fear, finally, I put them out.

At daybreak Bobo pulled his chain to the door, and I let him out. It seemed doubtful that he would come back, yet at dinnertime he was there. The evening’s events repeated those of the night before: the chain, the rejected food, the elaborate indifference to the lemmings, the refusal to acknowledge that I was there. A week passed with no change in our routine.

The weather outside turned into a fullscale. raging blizzard. The snowplow crews gave up. The oil trucks no longer could make. their rounds. The kitchen cupboard showed distressing gaps, but there was plenty of meat. A hunter had given me a forequarter of moose and the day the storm started I had bought several pounds of hamburger (at $1.50 a pound ) to see whether Bobo's hunger strike could be broken. It turned out that he scorned the hamburger but couldn't resist the moose meat. I ate the hamburger.

One evening about eight o’clock I unsnapped Bobo’s chain. He didn’t look up. He showed no surprise. But he slowly rose and with dignity walked to the door—on the way passing within two feet of the lemmings' cage and not even turning his head. When he returned he ignored the lemmings again, lay down, with a deep sigh relaxed and soon was asleep. I too relaxed, for the first time in weeks. I had a dog now that could be left alone with the lemmings quite safely.

They hate to be crowded

I was able to concentrate on finishing my book about arctic wildlife. Over the several months of watching and keeping records, several facts had developed that could have a bearing on a few of the unanswered questions concerning lemmings.

There was a great variation in their activity, or, as it seemed, their nervous tension, their restlessness. The weather might be an influence, but more definitely so was the phase of the moon. I had long known that I was apt to have migraine headaches near the time of full moon, and here were my little lemmings, nearly going mad for exactly the same two or three days. They fought so frequently that I had to keep a tub of water in which I could put them to calm them.

But it was the number of miles run on the wheel that furnished conclusive proof. Normally they would run about nine miles a day, but half again as far just before the earth came into line between sun and moon. Since those conflicting pulls are strong enough to cause maximum tides it would not be surprising if they could be felt by living creatures. If the lemmings’ periodic frenzy were intense enough, one of those times it might set off a migration.

But why would they not simply run around aimlessly near their nests—why leave their familiar environment? 1 had a clue to that too: my lemmings could not tolerate more than a certain degree of crowding.

Again and again I tried putting more and fewer of them into the big glass cage. In that space, four would live with little discord, except when the moon was full. If I introduced one more lemming, all five became desperate. Six or seven so disturbed one another that I never dared leave that many together for long. But even so two were killed in fights.

Since the lemming population increases phenomenally every three or four years, it may be that they reach a number intolerable to them and they try to escape from the crowding that so offends them. When lemmings do migrate, they have an impulse to run down. If they were attempting to get away from one another but were all running down, they would run together. Down the folds in the hills, down gulleys, down valleys: their direction would take them at last to the sea. That they w'ould cross rivers easily in their flight was evident from

their skill as they swam in my tub. And the ocean w'ould look to them only like another, very wide river.

Perhaps no one will ever know positively the reason why lemmings do migrate to the coast line and drown, but I had found with my little colony what to me was a satisfactory explanation.

I never did find, though, the explanation to one final enigma of the lemmings. Toward the end of my studies there were four lemmings left in the upstairs room, running about, spinning their wheel, chirring. Then from a cer-

tain day on there was complete silence.

With the help of some Eskimo boys I cleaned out the room. We sifted the earth in which they had burrowed; almost stalk by stalk we removed the grass they had not eaten; we took out the driftwood one piece at a time. No lemmings were there. They were just gone—a fact to be added to the rest of the lemming mysteries. ^

This is an excerpt from Wild Voice of the North, to he published soon hy Doubleday and Company.