Dispatch #16
In the first weeks of May,   the porous limestone country north of Winnipeg, Manitoba, becomes the scene of  greatest orgy in nature, as thousands  of red-sided garter snakes emerge from their winter dens and procreate in huge, writhing mating balls. All garter snakes den communally, but this is the largest gathering of snakes on the planet, the only place where you can take in ten thousand at a glance. It is an  anachronistic expression of the riotous abundance of life that once proliferated, comparable to the mile-long clouds of pierid butterflies that you can still be enveloped in along the Congo River,   and particularly heartening because snakes have always been the most persecuted group of animals.

        My eight-year-old son, Zachary, belongs to  seven generations of naturalists, going back to Russia in the l830s. Most of  them were lepidopterists; Zach is the first to exhibit a deep fascination for reptiles and amphibians. Part of this undoubtedly has to do with Steve Irwin, the fearless,  boundlessly enthusiastic  Australian “crocodile hunter” on t.v., whom Zach and his two brothers and millions of other kids are devoted fans of. But Zach possesses a remarkable empathy for other forms of life that I have encountered in only a few people in  thirty-five years of writing about the natural world and those who study it.    I’ve learned a lot from him about snakes, salamanders, frogs, and turtles--  subtly beautiful creatures I had never paid much attention to, watching him  turn over rocks in Montreal’s Mount Royal Park, which we live on the edge of,  and uncover hundreds of red-backed salamanders, or net aquatic forms of red-spotted newts in ponds around our country place in the Adirondacks. Turning up a corn snake on a Vermont farm, a western diamondback on an Arizona ranch within minutes of his arrival on the scene, Zach has shown me that reptiles and amphibians are far more ubiquitous and omnipresent than I had suspected, even with the assault they are under from so many quarters.  

        Zach’s mom, my wife, grew up in a village in Uganda, where a spitting cobra once slithered into her hut, and flying snakes took off from the tips of tall grass and caught small birds in mid-air. Like many people, she is terrified of snakes, and it took months of  pleading by Zach before she finally agreed to let him have a pet snake, a rough green snake, whom he named Minty. Minty was  maybe twenty inches long, impossibly thin, and  totally docile.   Zach posed for our latest Christmas card with  Minty curled around his fingers. But one morning a few months later, Zach  found Minty dead in his terrarium. There had been no indication anything was wrong with him.  Zach was inconsolable. To cheer him up, I decided to take him to  see the snakes in Manitoba.

      Their sexual frenzy usually peaks around Mother’s Day, but this year it was taking longer for them to come up from their subterranean hibernacula, the lack of insulating snow cover over the bitterly cold winter having driven them further down, and the bacchanal was only just getting underway when we arrived on Victoria Day weekend (the Canadian equivalent of Memorial Day weekend), a week later. 

       Flying into Winnipeg, we headed north up  into the interlake region,  between Lake Manitoba and Lake Winnipeg, most of which is dead flat, like most of the province. Only scattered copses of the original aspen parkland remained, like little islands in a sea of wheat and flax. After an hour or so, the soil got noticeably thinner. Cattle were grazing in rocky pastures, and in places the limestone bedrock was exposed. We could see scratches on it from the immense glaciers that had slid over it ages ago and brought down granite boulders from hundreds of miles to the northeast. The deeper gouges were filled with   finger lakes, swamps, and marshes full of frogs. This was great habitat for snakes, but not for humans, and like most of  rural Manitoba, and the interlake region is losing population. The dens are near an old Jewish colony called Narcisse, which only lasted from l903 to l914 and was abandoned after the railroad passed it by. All that is left of Narcisse is its graveyard, which is kept up by one of the descendants of the nineteen families who emigrated from Ukraine; he owns big malls in Winnipeg.  Chatfield, the next settlement to the north, is down to nine full-time residents. So it is  safe to say that the greatest vertebrate biomass in the r.m., or rural municipality, of Armstrong, which Narcisse and Chatfield are in, is not human, but reptilian.

      Four of the dens, containing an estimated fifty thousand snakes, are in the fifteen-thousand acre  Narcisse Wildlife Management Area, which was created from the Nariccse communal pasture  in l982. We rendezvoused there with Bill Preston, the emeritus curator of herpetology at the Manitoba Museum and the author of The Reptiles and Amphibians of Manitoba. Bill has been visiting the dens for forty years and was instrumental in getting them protected. “When I first got here,” he recalled, “there was a guy named Pikowski who collected the snakes for biological supply houses, and native Ojibwa snake-pickers would set down sheets of tarpaper in ditches overnight, and in the morning hundreds of snakes would be warming  themselves up under them. Many of the biggest snakes were shipped to the States, where they were sold to pet stores and  dissected in high-school and college labs. We had a meeting at the museum, and got the province to limit collecting to only in the fall, then we got it stopped altogether and  the four most productive dens annexed as provincial crownlands. 

      Why is Manitoba, at the northern limit where reptiles can live, so congenial to garter snakes ? I asked. Bill attributed this to the combination of the karst topography providing roomy chambers for them to den together in, and the availability of an abundance of frogs.  The winters here can go down to fifty below Fahrenheit, but  the  caverns stay forty degrees above year round. But the snakes also den in shaley cliffs, and in the granitic  Precambrian shield, to the east. Fifty dens are known in the province, but there are undoubtedly many more. 

         The red-sided garter snake, Thamnophis sirtalis parientalis, is one of thirteen subspecies. Its lateral lines vary from pink to orange to yellow; the top line is usually yellow, but not always. How the colors vary from den to den and relate to predation and mating success is under study. 

        Dian Neuman, a young interpreter with the provincial conservation department, took us to Den 3, a sinkhole (where one of the underground chambers had collapsed) on whose floor dozens of snakes were probing their way among newly leafed-out burdock and stinging-nettle plants. Some had formed   wriggling balls. “So far it’s been more of a trickle than a flood,” Dian told us.  The den was fenced off, to keep schoolchildren from going down into the pit and stomping the snakes, which used to happen. Now schoolchildren across Canada are taught that May is snake emergence month, and are assigned essays to write about the importance of helping the snakes get across  highways as they disperse to their summer range. Some of these snakes had already climbed  the walls of the sinkhole and were making their way into the woods. Zach was in seventh heaven, almost in a trace, picking one after another up gently and unhesitatingly and holding it for a while before placing it back in the grass. The snakes were totally docile; this is the place for someone with a phobia about snakes to come and get over it.   “I have never caught so many snakes in my life,” Zach exclaimed. “This is the most wonderful thing that has happened to me. I wish you good luck and hope you  don’t get eaten or stepped on or run over,” he said to one that Dian identified as a female. The females are longer and thicker. Some have the girth of a loonie (a Canadian dollar coin) or even a toonie (a two-dollar coin). Unless they are gravid, their tail bases taper more abruptly than the males’, whose thicker tail bases house their hemipenes, or paired copulatory organs.  

     The vast majority of the snakes we were seeing were foot-and-a-half-long, year-and-a-half-old males. The males emerge first, in great number, and heating themselves up in the strong spring sunlight, wait for the females, who emerge singly, nervously, exuding attractive-smelling pheromones. Most of them are quickly mobbed by the males. Up to two hundred males will vie for the chance to penetrate them. We saw several dead females who had been smothered in the melee. Some females manage to run the gauntlet of the males and to sneak off to safety. Some are chased up into bushes or trees, where the bigger males are lying in wait for them. We saw several saskatoon shrubs, in white flower, englobulated with mating balls, dripping with snakes.

       After inseminating the female, the successful male plugs her with  gelatin secreted from his liver, which soon hardens, and she emits different, unattractive pheromones. The other males leave her alone, and she makes her way to the summer range,  along with other inseminated females, and ones who have eluded the males and will meet up with boyfriends later, in less stressful circumstances, and smaller males who have little chance of squirming and muscling their way up to the female in a mating ball.  Heading  for the swamps and marshes at the top speed of a person walking, they feast on wood frogs and boreal chorus frogs. The imperative is now to eat. Each snake has lost ten percent of its body weight over the winter, Dian explained, and has been losing another one percent a day since it emerged. But many don’t make it. Some are caught by crows, hawks, seagulls, bald eagles, thirteen-striped or Richardson’s ground squirrels. Others are run over by cars and trucks.

        We were joined by Dan Roberts, Manitoba Conservation’s “wildlife technician” for the interlake region, who told us that last summer eight thousand snakes were killed on Highway 17, which runs along the western edge of the park. Even though twelve new culverts had been put under the road and a long fence along it, thanks to the generosity of  Hydro Manitoba, the province’s power company.  “There are more things we need to do to the fences, right where they meet the culverts,” Dan said. Another fifteen to twenty thousand snakes perished in the winter of l998-9, when a sudden frost caught them before they had descended below the frost line. “The dens have not made a comeback from this disaster,” he told us. 
     We saw several dead snakes whose livers had been pecked out by crows. Seagulls were wheeling and crying in the air. You’d think there would be a feeding frenzy at the dens, and some do experience massive predation, but not these; apparently the birds find the newly emerged snakes still too cold for their liking.
     Even with all this attrition, enough females make it to the swamps, where they bear up to twenty live young (garter snakes are ovoviviparous, as opposed to oviparous), which they have nothing further to do with. The gelatinous plug falls off, and the females mate again. One brood can have several fathers, but the female has young only every two years. She can store the sperm, sequestering it over many ovulation cycles yet still keeping it viable, before she finally gets pregnant. Dian said that one female in a lab had young seven years after her last contact with a male ! The young snakes spend their first winter at the summer range, in anthills and other warm places, and in their second fall, they return to the dens with the others. 
       Dan took us to three other sinkholes that were in the Narcisse community pasture. One had maidenhair ferns sprouting from its walls, and several very large, old females. Garter snakes can live for eight to ten years. In another, a group of six young males were poking their head up of the sinkhole floor, like  human teenagers scanning the scene for female action, although their flicking tongues were more important for sensing it than their eyes. 

      We spent the night in Inwood, twenty minutes south. Each town in rural Manitoba has a statue of its “mascot,” some animal-- a beaver, a stag, a turtle, a catfish, a giant mosquito—that is like its  totem, asserting itself against the endless flatness. Inwood has a statue of two huge entwined garter snakes. There was a lunar eclipse that night that turned the moon blood-red for an hour. The province was parched from several years of drought, and the next day the temperature went up into the eighties, bringing up the snakes in force, but also creating the most dangerous forest-fire conditions in Manitoba’s history. We returned to the Narcisse dens, but had to share the experience with twelve busloads of schoolchildren. Dan had said that landscape architecture students at the University of Manitoba were working up an ecotourism master plan for the park, which would determine its human carrying capacity. A stewardship program for the dens on private land was also being developed. 

     Zach and I decided to find our own den, where we could commune with the snakes in peace. The interlake region is absolutely saturated with garter snakes, so we had no trouble finding one,  in an abandoned quarry, whose limestone had been crushed to make air strips during the Second World War.  The snakes were oozing out of the fissures and crevices in one of its khaki walls. Many had already made their way up into the aspen parkland, so many that we had to watch where we were stepping. “You went right under my sneaker. I could of squished you,” Zach admonished one.  The  crackling and rattling grass that they were slithering through was so loud that it sounded like a cornfield being skeletonized by grasshoppers. The woods were alive with all kinds of creatures : mourning cloak, Melbert’s tortoise-shell, and polygonia anglewing butterflies had also emerged from their hibernacula; fritillaries and blues were skipping about. A few hundred yards behind the trees we could hear the clucking and chirruping of some northbound sandhill cranes. I followed four snakes, flowing together as if they were a single serpent, in a concert of contact, the female a head ahead of the three males, who were flanking her, riding shotgun. It was a sight that dispelled any doubts one might have about the beauty of snakes. I remembered a passionate apologia for them that a half-crazed American herpetologist who had been wandering in the Congo basin for twelve years and was probably never going to go home and write up his disseration, gave me twenty years ago : “Snakes are so clean. They have no arms or legs, they can’t talk, they can’t hear, they can barely see, they can never close their eyes (which is how the superstitition about their hypnotic powers got going). They don’t have bladders, they don’t get parental care—and with all these handicaps, how is it that every snake from the day he is born knows how to swim, to climb, to crawl on the earth, to catch food, to run from people who want to kill it ? How is it that they have successfully invaded every habitat ? I think snakes are just the most beautiful creatures God created. Even more beautiful than women. They’re ballet in motion.”
       In another den, where thousands of snakes had surfaced, we found Dr. Rick Shine, a behavioral ecologist from the University of Sydney, who has been coming here for five years, picking ones he wanted to study more closely and putting them in a cotton bag. Dr. Shine was very busy—the morning hours were precious—and he had no time to answer my beginners’ questions. But he said we could meet that afternoon for a chat at the research station in Chatfield. Why have you been coming here all the way from Australia, which (as anyone who watches Steve the Crocodile Hunter knows) has one of the world’s most spectacular herpetofaunas ? I asked.

       “I study snakes all over the world,” Dr. Shine replied, “but there are more snakes per square meter here than anywhere on the face of the earth, and they are very docile and unafraid of humans, so this system provides a unique opportunity to conduct all sorts of behavioral experiments that aren’t possible anywhere else. Many involve their extraordinarily sophisticated chemical and hormonal communications systems, which human don’t have. With a single flick of their tongue, they can tell the sex and the body length of  another snake, and whether it belongs to the same den. We’ve discovered that some males mimic the females, producing the same sexually attractive pheromones when they first emerge from hibernation. We call them she-males. They only do this for a day or two, then switch back to being hot-blooded males. What the benefit of this  could be is very puzzling. Perhaps it is that  during this short period they are vulnerable to attack by crows, so being covered by lots of other snakes protects them.”

        What degree of choice does the female in a mating ball have over which male she will be inseminated by ? Does she gape her cloacal aperture for the one who pushes her buttons ?   Dr. Shine doubted that the female could be very selective in such a chaotic situation. “There is a strong element of sexual coercion at the den,” he said. “The males are stressing the females, and form mating balls even with juveniles. But once a female reaches the summer range, she is probably able to exert more choice.

        “My colleague Dr. Bob Mason of  Oregon State University at Corvalis, who has been coming here for twenty years,” he went on, “has marked some of the snakes, and has discovered that they disperse up to twenty kilometers from their den, and that almost every snake comes back to the same den, and that each den is genetically unique. Whether they follow pheromone trails when they disperse and return, we don’t know. They probably use a whole range of navigational techniques—compass, sun orbit.”
       I asked Dr. Shine, who was impatient to get back to his work—he and several of Dr. Mason’s graduate students had been poring over notebooks of data—what he found so interesting about snakes, and there was a pause as he decided whether he was going to dignify the ignorance of this query with an answer. “I think snakes are very beautiful, mysterious, elegant, and glorious,” he said at last.

       The sex ratio of each den, by the way, is about equal, even though the ones you see are overwhelmingly males.  

       The garter snakes around here den not only in sinkholes and quarries, but in old foundations and wells. They have colonized the Inwood creamery, and even the crawlspace of Inwood Manor, the local old folks’ home, and crawling up its vents have appeared in its hallways and rooms, scaring the daylights out of the residents. “They seem to like the manor and just in the last few years they’ve gotten bad,” the manor’s cook told me when we dropped in that afternoon. “We saw probably a dozen over the winter, but now they have probably left to wherever they go. They do their snake business in the summer months. This summer we’ll be doing major excavation around the whole building so they won’t be able to get in anywhere, so that should take care of it.”

     We spoke with a white-haired woman named Ethel Dadswell, who was knitting in the television room. Ethel was the resident snake-catcher. “I hate them-- enough to pick them up and throw them out the door,” she told us.

     Why are people so afraid of snakes ? I asked. 
      “You’ve got to admit they’re a nasty-looking thing,” Ethel said. “Okay, you can see them outside, and that’s fine. But when you’re sitting here reading, completely relaxed, and there’s one in the corner, with its head reared up and looking around—that’s not a pleasant thing. I’m one of the people that nothing much bothers. If something needs to be done, I’ll do it. But others have a very real fear. They scream and scream and get frantic and can hardly breathe. That’s not a nice thing, when it can be controlled. I’d like someone to tell me why they’re so precious. What good do snakes do ?”

      “They eat bugs and help keep things in balance,” Zach said. 
       “They  keep down the frog population,” I suggested. 

       “They torture the frogs,” Ethel countered. “A frog is a nice thing. Frogs don’t do us any harm. Where I grew up, in Norris Lake, eleven miles south of here, when spring came, the frogs used to sing me to sleep, but here you don’t hear anything because there are so many snakes. If all they do is kill the frogs, then I’d rather not have them. This thing that they’re absolutely harmless—that doesn’t apply to anything. Not even people.” 

          “I don’t see how anyone can not like snakes,” Zach got up the gumption to say. 
          While we were talking, a big forest fire, one of dozens that had broken out in the province that day, was raging to the east. The entire town of Fraserton (pop. tk) had to be evacuated. But in the middle of the night there was a thunderous downpour, saving Manitoba from disaster. In the morning Zach and I went to pay a last visit to our secret den, to say goodbye to the snakes and see what they do on a rainy day, whether the wetness had slowed their emergence and dampened their ardor. Some were out and about, but not as many as the day before. Zach picked one up from a large, writhing pile. He turned over a rusty metal plate, exposing hundreds more. “Come on, Zach, we have to go,” I said. 

       “Just one more snake,” Zach pleaded, and he picked up another one,  and laying it back down softly on the scree said, “Bye snakey. I love you.”