The Island of Giant Mice

Two thousand miles east of the coast of Argentina, Gough Island rises out of the Atlantic Ocean in an awesome display of ancient volcanic activity. A green carpet of windswept mosses and grasses covers 35 square miles of jagged peaks and steeply sloping valleys. Waterfalls spill out of craggy cliffs and fall hundreds of feet to the sea, which runs uninterrupted for another 1,700 miles before crashing into the tip of South Africa. It is one of the most remote places on our planet.

Four miles west of the University of Wisconsin– Madison campus, the Charmany Instructional Facility is a low-slung labyrinth of concrete hallways lined by bright fluorescent lights and permeated with a smell that is equal parts animal and antiseptic. Part of the UW School of Veterinary Medicine, Charmany is nearly half a world away from Gough Island (pronounced “Goff ”). Yet the two locations share a common trait— they both are home to the largest mice on Earth.

In terms of body size and weight, Gough Island mice are twice the size of their mainland cousins, notes Bret Payseur, a geneticist with a joint appointment in CALS and the School of Medicine and Public Health. “The amazing thing about them being twice the size is that they’ve only been on the island a couple of hundred years,” he says. The island’s early rodent settlers were a more moderate-sized strain of Mus musculus, house mice stowaways in the holds of sealing ships from Western Europe. But somewhere along the line, Gough Island mice outgrew that ancestry—doubling in size over the course of only a few hundred generations. “That’s incredibly rapid evolutionary change,” Payseur says. “It’s some of the most rapid that I know about.”

In the canon of origin stories, however, this tale reads more like a mystery. How did the Gough Island mice get so big so quickly? It could be that a genetic mutation proved so advantageous that huge mice became the norm. Or maybe conditions on the island favored preexisting genetic traits that had lain dormant until the mice became castaways. For the time being, however, the Gough mouse story is transcribed only in A’s, T’s, C’s and G’s—the nucleic acids that write genetic code. Payseur hopes to translate that text. What he finds could not only shed light on evolution in action. It could also help illuminate the genetic mechanisms underlying human metabolic diseases like obesity and diabetes.

The Island Rule

While Gough Island mice are unusually large, it isn’t unusual for small animals on islands to grow bigger than their mainland counterparts. The phenomenon is often referred to as the “island rule,” which states that, in general, small animals tend to get bigger and large animals tend to get smaller once they’ve been island castaways for some period of time. There are, of course, exceptions. But from giant Komodo dragons to extinct pygmy mammoths, examples of the island rule run throughout the animal kingdom.

The gigantism effect of this rule seems to be especially pronounced in rodents. Human history is full of daring adventure on the high seas involving fearless mariners and the obligatory stowaways—mice and rats. As a result, the world’s islands are full of transplanted rodents. Biologist J. Bristol Foster first posited the island rule in a 1964 paper in the journal Nature, titled “The Evolution of Mammals on Islands.” In his study, Foster looked at 69 populations of island mice off the coasts of Western Europe and North America. The mice in 60 of those populations were measurably larger than their mainland cousins. Since that study, time and again, scientists find mice and rats on islands that are markedly bigger than genetically similar mainland populations.

This is notable because, in evolution, random genetic mutations or suddenly shifting environmental conditions can lead a species down a certain path. Which means that chance plays a big role in charting a species’ history. “If you ‘run the tape’ once and go back and run it again,” Payseur says, “you would expect different outcomes because of that role of chance.” When patterns like the island rule appear in evolution, he says, “People get very excited. It suggests that what underlies the patterns is a common mechanism that would tell us something important about how evolution works.”

Payseur’s scientific background is anchored in evolutionary biology, and the natural history of species on islands has fascinated him throughout his career. After early work with primates in Madagascar, Payseur realized that, while there is a lot one can do in primate research, keeping captive colonies of lemurs in a lab and breeding the thousands of crosses needed to actually get at answers wasn’t one of them. So he turned his attention to mice.

“The great thing about house mice—and I know most people don’t think house mice are great—is that the strains or lines of mice that people study in the lab are descended from wild house mice, including the wild mice that often inhabit islands,” Payseur says. “So they’re kind of cousins evolutionarily and share a lot of the same traits. That means we can use the genetic tools developed for the lab strains of mice to understand what’s happening in wild mice.”

He’s looking to these small creatures to answer some very big questions. “In the very long term, what I would like to answer with this research is, ‘What types of genetic changes are responsible for the extreme body size on islands?” Payseur says. “Are they the same on different islands? Do we see the same genes popping up over and over again, or do organisms take different paths to get big?”

Knowing that he would have the time, money and resources to deal with only a single strain of island mouse at a time, Payseur decided to start with the most extreme example of the island rule that he could find. He turned to colleagues who studied house mice in the field—and every one of them pointed him to Gough Island.

An Incredible Journey

Most researchers simply order mice via catalog, usually from what Payseur calls “the world center for mouse genetics,” the Jackson Laboratory in Maine. A copy of their glossy catalog lets researchers pick trait-specific lines of mice, from body size and coat color to preassigned conditions like immunodeficiency. Then, simply place an order and wait a few days for the mail to arrive. Gough Island mice aren’t in that catalog. Which means that Payseur had to figure out a way to get mice from an incredibly remote island with a grand total of six to eight full-time human residents, all of whom were busy with their year-long stint staffing the South African National Antarctic Programme’s weather station.

The solution came in the form of an unusual and macabre adaptation of behavior in Gough Island mice. In addition to developing bigger bodies in their few hundred years on the island, they have also developed an appetite for bigger food—the chicks of nesting seabirds, which they, quite literally, nibble to death. Luckily for Payseur, there are quite a few people concerned about those seabirds.

Gough Island is officially a possession of Britain and part of the Dependency of Tristan de Cunha. It is also listed as a World Heritage Site by the United Nations Educational, Scientific and Cultural Organization, which recognizes Gough as a pristine, primarily untouched ecosystem. Its towering cliffs, according to the UNESCO description of the island, “host some of the most important seabird colonies in the world,” from the endangered Tristan albatross to the Atlantic petrel to the Northern Rockhopper penguin. Under such circumstances, a population of non-native, quick-breeding, bird-eating mice is of grave concern—especially to the governments and scientists tasked with preserving the island’s biodiversity.

Peter Ryan, director of the Percy FitzPatrick Institute of African Ornithology at the University of Cape Town, South Africa, says that, especially where petrels and albatrosses are concerned, Gough Island mice are a threat to breeding populations. Ryan has been an honorary conservation officer in the Tristan de Cunha islands since 1989 and has witnessed the decline in seabirds firsthand. When Payseur reached out to him in 2008, Ryan was working with Richard Cuthbert, a scientist at the Royal Society for the Protection of Birds, on a census of sorts to help the British government plan an intervention—or, rather, an eradication.

The mice “were easy enough to catch,” Ryan wrote in an email recalling Payseur’s request. “They occur at very high densities and we’d been live-catching lots of mice to estimate their movements and densities and to conduct poison trials to ensure that all were susceptible to the poison bait.” Ironically, in order to study how best to kill them, the researchers had the live traps, food, bedding and other paraphernalia needed to keep the mice alive for study.

The “big issue” Ryan recalls, was shipping them. Eventually, the crew of the S.A. Agulhas, a South African Antarctic research vessel, agreed to give the mice a lift, but “Even this was a bit tricky, because we had to convince them that the mice wouldn’t be able to escape.” In the fall of 2008, 50 Gough Island mice boarded a boat and took the return trip to the mainland, specifically Cape Town, South Africa. After a lot of paperwork they were sent to Johannesburg, with inspections and quarantines and mountains of paperwork piling up as they made their way by plane to Europe, then to Chicago and, in a final car ride, to the campus of the University of Wisconsin–Madison, where postdoctoral researcher Melissa Gray was waiting.

That September, Gray had just begun her stint in Payseur’s lab. The idea of working with mice excited her, since, as with Payseur’s initial study of primates in Madagascar, the Channel Island foxes she had been working on promised to be a difficult study organism. When a mentor suggested she reach out to Payseur, Gray says, “It was a perfect connection.” She had a background working on island populations and the genetics of size and “Bret already had this project and nobody to work on it.” Plus, she wouldn’t have to wait long to get going. “I started in Bret’s lab in September,” Gray recalls, “and the mice arrived in late October.”

Immediately upon their arrival, the Gough Island mice alleviated any concerns about their suitability as a study subject. “Basically it was a cardboard box with some breathing holes and food stuffed inside,” Gray recalls. But when she opened the box, “It was amazing,” she recalls. Ryan had sent 50 mice off to Wisconsin. Forty-five survived the trip and, even better, they’d managed to produce a couple of litters along the way. They hadn’t even begun their experiment, and already the Payseur Lab was growing a colony of Gough mice. “In a way, we ended up with more than we started with, which is crazy with the amount of stress they were under,” Gray says.

After that initial excitement wore off, the real work began. First, Gray had to randomly breed several sets of mice to ensure that their large size was genetic and not the result of conditions on the island. When those lines came out as big as the wild-born mice, she could turn her attention to creating the first lab-raised line of Gough Island mice, inbreeding some promising strains of mice to create lines that were genetically identical, which makes gene mapping much easier. These mice would then serve as the lab’s breeding colony, slated as mates for lab mice with a mainland heritage.

One way to think about the process—to borrow a metaphor from Mark Nolte, a current postdoctoral researcher in the Payseur Lab—is to imagine two decks of playing cards, one red and the other blue, where each card is a gene. Each deck represents a chromosome, a long strand of DNA wrapped around proteins that carries genetic instructions from a parent to its offspring. When sexual reproduction occurs, each parent contributes a copy of one of their two chromosomes to their offspring.

Imagine the Gough Island mice as having two blue decks of cards—one deck for each chromosome—and the mainland mice as having two red decks. Their initial mating yields what’s called a “filial generation one,” or an F1 baby mouse with two distinct chromosomes, one with all blue cards and the other with all red cards. But when an F1 mouse mates with another F1 mouse, those decks get shuffled. These “filial generation 2,” or F2 mice, hold the first key to untangling the riddle of the evolution of Gough Island’s giant mice.

Breaking the Code

In a small, windowless room at the Charmany Instructional Facility, doctoral candidate Michelle Parmenter lifts two wriggling brown mice out of separate plastic cages by the base of their tails. One is from a line of laboratory mouse with a lineage that runs, if one looks far enough back, to a population of U.S. house mouse. The other is also a strain of laboratory mouse, although it’s of the lab’s own creation—its Gough Island heritage evident in the way it dwarfs its companion when nestled side by side in Parmenter’s hand.

Parmenter, Nolte and a half-dozen Payseur Lab undergrads spend a large portion of their time taking measurements, plopping each of the 480 mice in the room—increasingly inbred descendants of the original Gough mice—one by one into an empty container of French onion dip and putting it on a scale.

Parmenter has slipped on tough blue “bite gloves” before handling the mice— and one mouse’s attempted nibbles remind her why she needs them. “Okay, you’re trying to bite me,” she announces, putting the critter down. “These bite gloves are good, but they’re only so good.”

A smaller mouse, on the other hand, sits meekly in her palm. Parmenter and Nolte say there are a lot of anecdotal differences in behavior between the Gough line of mice and their mainland counterparts. Gough mice scrabble at the corners of their clear plastic cages and frantically scale the grates near their water bottles like monkey bars. The mainland mice spend more time quietly nestled in the shredded paper bedding provided for burrows. When working with the mice, Parmenter and Nolte put them in deep plastic basins, since the Gough mice seem to be strong jumpers and more aggressive. In comparison, says Nolte, “I could work with classical laboratory strains of mice on a level surface and they wouldn’t go anywhere. They wouldn’t even try to escape.”

While they enjoy discussing the potential evolutionary drivers behind some of this observed behavior, what is really exciting to Parmenter and Nolte is what these mice are now telling them at a genetic level.

By crossing mice from Gough and the mainland strain, the Payseur Lab has produced about 1,400 F2 mice. They’ve extracted DNA from each one, sent those samples to a lab for analysis and, in return, received a genomic portrait of each mouse’s DNA. Combing through all of that is a slow process, says Parmenter, but already they are finding hints of the genetic code responsible for their remarkable size.

“Imagine I take the two decks of cards—or ‘chromosomes’—and spread them out, and I can go down each row and say, ‘Oh, there’s a mainland chunk of DNA,’ or ‘Hey, that one came from Gough,’” Nolte says. When you do this enough, patterns begin to appear. “If you take your largest mice and spread their decks, you notice that at the same position on the chromosome they all share the same Gough DNA.” When a big enough percentage of large mice show the same chunk of genes at the same position on the genome, Nolte says, it indicates that, somewhere in the region, there is a gene responsible for size.

That strong association, however, isn’t exactly a smoking gun. When the project began, says Payseur, a prevailing thought was that the rapid evolution in Gough Island mice would be the result of mutations in just a couple of key genes. But in a September 2015 paper in the journal Genetics, the lab published its first genetic mapping results from the F2 crosses, reporting that 19 different sections of the genome appear to play some role in the rapid and extreme size evolution of Gough Island mice. Each of those 19 sections is comprised of anywhere from 400 to 1,400 genes, which means there is much more work to do.

Right now, the process “is not getting at a specific gene,” says Gray, who was the lead author of the Genetics paper. “It’s saying, ‘Okay, this chunk of genome right here somehow corresponds to body size.’ So if you want to tease that apart more, you have to shuffle the deck again. And then shuffle it again.” Keeping your eye on the right card gets difficult. “You really need a lot of samples to get past the noise,” she says, “and that’s a challenge about a project like this. You need a lot of individuals, and that means a lot of money and a lot of time and a lot of mice.”

The Search for a New Island

As the “giant mice” experiment currently stands, the Payseur Lab will, eventually, uncover specific genes that are responsible for the Gough Island mouse’s astounding size, work that could have implications for research on things like human metabolic diseases or even breeding livestock.

“When you look at domesticated animals, size is one of the most important traits because it’s correlated with characteristics like productivity,” Payseur explains. “There’s a lot of interest in CALS in understanding the genetic basis of size variation—in that context it would help select for increased body size and know what genes confer the response. Maybe there’s a more efficient way to ‘build the animal.’”

But if Payseur is to truly unravel the evolutionary mystery of the island rule, he’s going to not only need more time, money and mice—he’s going to need a new island.

The idea is to run the same experiment with another population of large island mice and see if evolutionary patterns emerge. Do some of the same 19 genetic regions his lab has identified show up in those mice, or did they get bigger through a completely different mechanism?

“It would be nice to choose an island because it has similar ecological conditions to Gough that might have driven the same kind of body size increase,” Payseur muses. “But another consideration is, it would be nice to choose an island where the mice have come from a different part of the world. I’m in the throes of figuring that out right now.”

Either way, it’s not a decision that will be made quickly. And the project, which is funded in part by the National Institutes of Health, is slated to run for several more years, meaning that large mice will be calling a UW–Madison lab home for a while.

Gray has already moved on from the project, taking a job as a research scientist at Exact Sciences, a Madisonbased biotech company. Both Nolte and Parmenter realize that they’ll also head elsewhere in their careers before the full story of the Gough Island mice can be translated. But they admit to hoping that they’re still around when the next cardboard box full of large, wild mice arrives in the lab.

“Just knowing that Bret is pursuing a new island population makes us all giddy,” Nolte says.

Payseur shares their excitement, but he knew when he launched the study that he was signing on for what could end up being a career-long project.

“I think that genetics is the most powerful way to answer evolutionary questions,” he says. But getting at answers can be “more complicated than one might imagine,” Payseur admits. “It would be nice to have a simple explanation, but I tend to be attracted to more complicated projects.”

In one respect at least, things might be finally getting a little less complicated for the Payseur Lab: Wherever they turn next for a population of giant mice, the island in question will be a little less remote than Gough. And the mice involved will be a little smaller. And, just maybe, writing the next chapter of this story will be a little bit easier—aided by a key created from the genome of the largest mice on Earth.

 

The Fox, the Coyote­—and We Badgers

Once upon a time during the last few years, a red-haired girl new to the University of Wisconsin–Madison crested Bascom Hill and cast her eyes upon the cozy arrangement of buildings and lawns, the tree-lined city by the fair lake. Her nature and upbringing led her to think: Yes, this is good. I should meet the right boy here. I hope the food is good.

The UW–Madison campus is a well-worn locale for such scouting. Last year 31,676 prospective students scoped out dorms and classrooms. Hundreds of elite athletes measured the environment against their precise needs. Thousands more informal visits were made, all driven by the same question: Can I thrive here?

But our young visitor is in a new class altogether—wild members of the canid clan. As it happens, their food is quite good, and she—technically a vixen, or female fox—did find the right dog. After spending a winter holed up under Van Hise Hall, she gave birth to a litter of eight, and in early March of 2014 began to let the young kits gambol about.

They were a campus sensation—stopping lectures, cars and buses, inspiring a popular Tumblr blog, drawing hundreds of rapt spectators. Their appearance provided a fortuitous teachable moment for David Drake, a professor of forest and wildlife ecology and a UW–Extension wildlife specialist, who was just beginning to delve deeper into studying the foxes and coyotes of Madison.

Coyotes have been intermittent, if secretive, Madisonians for more than a decade. In the last few years reports of coyotes by visitors to Picnic Point have been rising, and people from the Lakeshore Nature Preserve asked Drake if he could investigate. But the rise of the urban fox population is a relatively new canine twist.

“It’s very timely,” says Dan Hirchert, urban wildlife specialist with the Wisconsin Department of Natural Resources. While no comprehensive data have been collected, from where he sits foxes and coyotes are gaining throughout the state. And while the coyotes have been present for a couple of decades, the fortunes of the fox seem to be following the rise in urban chicken rearing.

Because most wildlife research happens in rural areas, we may not know as much as we think about our new neighbors. “Does what we’ve learned about these animals in the wild apply in urbanized settings?” asks Drake. Most major cities employ a forester, but very few cities have a wildlife biologist on staff. Much more common is the pest management paradigm: animal control.

“It doesn’t make any sense to me,” Drake says. “If 85 percent of Americans live in cities, why aren’t we doing more? That’s where people are interacting with wildlife.”

These questions prompted Drake to found the UW Urban Canid Project, a hyperlocal study with far-reaching implications.

“The number of urban canid sightings on campus, primarily red fox and coyote, have been on the rise and have been met with mixed emotions from all different members of society,” notes Drake. “This research aims to understand more about the complex interactions between coyotes, foxes and humans in this urban area—as well as provide information and resources for residents to reduce the potential for conflict with these amazing creatures.”

As morning light seeped into a cold January dawn, David Drake and his grad student Marcus Mueller prepared to lead a small convoy from Russell Labs, winding toward the wild corners of campus to check 18 restraint traps that had been set the evening before.
“Are you feeling lucky today?” Drake asks, climbing into the truck.

“Always,” says Mueller.

“I had a hard time getting to sleep last night,” says Drake. “This is like the anticipation of Christmas morning. Every day you go out to see if you caught something.”

First stop is the old Barley and Malt Laboratory, between the retaining wall of University Avenue and the physical plant. It hardly seemed like habitat, but Mueller traced a clear track laid down by the repeated passage of many small feet. The animals were using the buildings for cover, in transit to someplace else.

Drake is hopeful—he’d already received a call from someone who’d seen a fox at 5:20 a.m. on the football practice field. “They were running through Breese Terrace all last year,” he says. At least one fox was digging in an area under the west side bleachers of Camp Randall for a possible den, notes Drake, but no kits were ever seen there. “It is funny to find these spaces on campus that the animals are using,” says Drake. “I ride my bike by here every day and never really thought about it.”

And in one of the three traps an annoyed raccoon waits impatiently. Donning protective gloves, Drake and Mueller release the coon, who scuttles away, anxious for cover.

Next stop is a small cattail marsh next to Willow Beach, behind the new Dejope Residence Hall. The day before, Drake and Mueller had baited the marsh with parts of a deer carcass. On the short trail we flush an eagle from its perch, perhaps planning its own morning snack of carrion.

This little ecological pocket typifies the habitat opportunities that fox and coyote are exploiting. It’s not big enough to call home, or even to get a regular meal. But link it together with dozens of other nooks and crannies and dumpsters around campus, and the sum total is a complex and productive niche.

Fox and coyote are urban adapters: flexible enough to range across a variety of landscapes, from rural to urban. For animals to survive in a city, they typically need to be this kind of habitat generalist, able to exploit a range of hunting and scavenging environments.

The other part of the equation is habituation—how animals get accustomed to human activities. As a species moves into the city, those who survive realize over time that bad things don’t necessarily happen when they encounter humans. Instead of running at the first sign of people, they sit and watch. This knowledge gets passed down from mother to pup, eventually leading to the Van Hise foxes romping in full view of adoring crowds.

The restraints behind Dejope are set for fox, and this morning there is nothing. Drake looks around and connects the dots in the surrounding environment. West across the ice is University Bay Marsh, where four more restraints await. A few ticks to the north is Picnic Point, and the lake beyond.

The last traps of the day are located in the Biocore Prairie, where the research began when a few trail cams confirmed that a group of coyotes were ranging through the preserve, and probably enjoying the fruits of the Eagle Heights gardens as well.
Drake hopes to learn how urban agriculture is influencing canid behavior. Backyard vegetable gardening is flourishing, and each year more city dwellers add chicken coops to their homesteads.

The chickens are an obvious attraction—chickens have probably been preferred canid targets since even before their domestication. Gardens also attract the small mammals that canids prefer. They will even snack on berries and vegetables.

Last year Drake secured four radio collars—two for each species—and, with the assistance of Lodi trapper Mike Schmelling, researchers were able to collar a pair of coyotes and one fox. Among the first discoveries was that the animals are running the frozen lake. The researchers learned this when one collared coyote disappeared. At first they suspected a malfunction, but a citizen report led them to Maple Bluff, where they reestablished radio contact. The coyote had apparently run all the way across the lake, possibly snacking on ice-fishing gut piles along the way. Another ran north and was killed by a car on County M, near Governor Nelson Park.

This year the research hits full speed, with 30 fox collars and 30 coyote collars available. The ambitious work plan includes collaring an entire fox family, kits and all.

And in the snow-covered landscape of the Biocore Prairie, the first glimpse of the third restraint trap offers a rush of hope. The area around the restraint is beaten up, with dark leaves interrupting the white. An animal was clearly held at some point, but all that’s left is a bit of hair and a kinked and ruined cable.

Back in the truck, Drake teases Mueller. “Marcus, I don’t have a good feeling about your luck.”

“Not yet, anyway.”

“You’re not an unlucky person, are you?”

“I hope not.”

“Because I have fired more than one graduate student for being unlucky . . .”

It’s just as dark and even colder the next morning, yet the party adds an undergraduate wildlife ecology student, Cody Lane, and Laura Wyatt MS’87, a program manager with the Lakeshore Nature Preserve. John Olson, a furbearer biologist for the DNR, is in town, and has come to check out the project before putting in a day of lab work.

Behind the Barley and Malt Laboratory, Olson kneels down to evaluate the tradecraft of the empty restraint—a simple loop of airline cable noose suspended from a dark length of stiff wire. “They don’t even see these as traps. They see them as sticks,” Olson explains.

These unique cable restraint traps were named and developed with DNR assistance as part of a national humane trap research program in the early 2000s. “The important thing with these kinds of sets is non-entanglement,” he says. The radius of the multistrand wire must be clear of any potential snags. The size of the loop is determined by the animal you’re selecting, while a stopper keeps it from getting too tight. It works much like a choker collar.

During testing they trapped just over 200 coyotes, and only two died. One had a bad case of mange and died of exposure. The other was shot by someone who didn’t realize the animal was restrained. “It’s a very safe tool,” Olson says. “Cable restraints never damaged any coyotes in the three years that we studied them.”

The convoy moved on to Willow Beach—and, finally, success. A young male fox waits suspiciously, huddled in the reeds. The wind probes at his deep winter coat while the party retreats and summons Michael Maroney BS’85, a veterinarian with the UW–Madison Research Animal Resources Center.

Together Mueller and Maroney estimate the fox’s weight at 12 pounds, and draw a mix of ketamine and xylazine. Mueller secures the animal with a catch pole while Maroney injects the cocktail into the rear leg muscle, provoking an accusing glare from the fox. The clock starts. Within six minutes Maroney looks at Mueller and announces: “He’s clearly gorked.”

Everybody laughs at the non-technical yet thoroughly accurate terminology, and the work begins. They figure they have about 40 minutes. Laying the animal out on a white towel atop a blue tarp, Mueller secures a cordura muzzle, then pulls out electric clippers and shaves one dark foreleg to make it easier to find a vein. Maroney watches his technique while the undergraduate Lane records data.
The fox breathes steadily, and the three talk quietly, as if he were only asleep. Without the wind ruffling his coat, the fox seems smaller, more vulnerable. After the blood draw, nasal and fecal swabs are taken, and the mouth examined. Finally, they weigh the animal—a sturdy 13.5 pounds—and affix the radio collar.

Removing the muzzle, they carry him away from an opening in the marsh ice—a gorked animal doesn’t always behave rationally—and lay him out again on the tarp, out of the wind. A few minutes later and a dark ear twitches, as if to displace a fly. A few more minutes, and the ear twitches pick up. Suddenly the fox stands up shakily, and surveys the audience of onlookers. He quickly takes cover in the marsh, where he gathers his wits for a few more minutes, then slips from view.

Mueller and Drake are giddy, ebullient. “We are off and running,” says Drake. “That was pretty cool.” Last year it took forever to catch a fox; this year they begin with one. “Great start,” says Mueller, and then recounts the steps to himself in a low voice, as if to help remember: the sedation, the blood draws, the recovery.

Mary Rice first saw the coyote in her backyard sometime in the summer of 2012. It was getting dark, and first she wondered, “Whose dog is that?”, followed quickly by: “Oh, my god, a coyote.”

“We were a little alarmed,” she says.

Rice canvassed the neighbors, warning them there was “a coyote lurking” about. Some didn’t know, others did, and some even thought they’d seen wolves. She was wondering how to deal with it, who to call, when she saw another one, smaller. “Remove one, there will be another,” she realized.

A graduate coordinator in the Department of Food Science, Rice remained somewhat unsettled for a few months, worrying about her cats and unsure about her own safety. Then one day at work she learned about Drake’s UW Urban Canid Project and decided to give them a call.

“Can you try to track it and figure out what it’s doing here?” she asked. “We can hopefully live with it. If we’re not going to be able to remove it, maybe we can learn from it and learn how to live among them.”

Before long, with the cooperation of another neighbor, a restraint trap was set. This was Mueller’s first solo set: he decided where to put it, and configured and camouflaged it. Within a week, in early March they had a 36-pound male coyote who had been cutting behind a brush pile. On her way to work, Rice stopped to see the animal and help the team record its vitals. She couldn’t wait to tell her coworkers why she was late.

Rice’s coyote experience is a perfect example of how the project can work, says Drake, with outreach engaging members of the public and connecting them with scientists in the field. On most trap-checking mornings Drake’s team has company—each day a new handful of visitors. Sometimes they’re wildlife students or other friends of the program, but often they’re just curious early risers who follow the group’s progress on social media.

And with hundreds of followers on Facebook and Twitter, public fascination is strong. Because of our strong cultural connection to dogs, our affinity may even be a little hardwired. From Wile E. Coyote and fox or coyote tricksters in folklore to the Fantastic Mr. Fox, these are animals we all know on some level, however mythic.

Still, fox and coyote don’t get quite the same reception. The fox is easy to anthropomorphize. It’s small, cute and generally non-threatening. Coyotes aren’t typically seen as often, and your first thought can be, like that of Mary Rice: Whoa, that’s a pretty big animal.

“Just because you see a coyote doesn’t mean it’s a bad animal, and doesn’t mean it’s going to create problems for you or that you should be afraid of it,” says Drake. The key is to not create, or exaggerate, a conflict. And that’s almost always about food. It’s important to secure bird feeders and outside pet food, and to take care with pets out of doors. If the coyotes become too bold, make an effort to scare the animals away. “We’re really trying to help people to understand how wonderful it is to have these animals here, but also to be vigilant,” Drake says.

“Are you nocturnal yet?” I ask Mueller as I climb into a white UW van at 9 p.m. in early March. He laughs—it won’t be long now. As soon as early-morning trap checks are done, he’ll be swinging full-time on the second shift. These dogs are nocturnal, and if you want to learn where they are at night, you’ve got to get out there with the radio tracker.

The research plan calls for tracking each animal at least once a week. Some nights it’s boring, and Mueller catches naps between hourly triangulations. But the newly collared fox has been a real challenge. He was tracked one night moving from south of Fish Hatchery Road and Park Street all the way up to John Nolen Drive, where he spent time on frozen Monona Bay and eventually made it to Muir Woods on campus. That’s about four miles as the crow flies—never mind the urban labyrinth he had to navigate between those points. He did all that traveling within a five-hour period.

“It truly was a game of cat and mouse trying to keep up with him that night,” says Mueller. Is he a young transient who hasn’t yet established a home range? Is he trying to find a mate? Or can home ranges for urban foxes really be that big?

Some nights Mueller can track only one animal, but on others they are close to each other. On one recent night the fox and the coyotes were all on campus, just a short distance from each other. “I was flying all over campus,” says Mueller. “It was a crazy night of telemetry.”

It was a perfect scenario for answering a really big question. In wilder terrain foxes and coyotes are mutually exclusive, but Madison is different. “We know from the animals we’ve got on radio that the fox and the coyote are sharing the same space, and sometimes they are sharing the same space at the same time,” says Drake. “They are crossing paths.”

Are the foxes using humans and elements of our built environment to protect themselves from coyotes? Or are there simply enough resources that they don’t have to compete as strictly—more rabbits and squirrels, more compost piles and chicken coops?
The scientists are a long way from answering those questions. First they need to relocate the coyote.

Mueller parks around the corner from Mary Rice’s house in a residential pocket south of the Beltline and raises the antenna, a three-element Yagi that looks like a refugee from the old days of analog TV.

The first reading comes from the west, and from the strength of it Mueller guesses we’re a mile or more away. Crossing back over the Beltline, a little under a mile as the crow flies, and another reading: now the signal’s coming from the east. Another three-
quarters of a mile into a dead-end parking lot, and the signal is now east and south. But back over the Beltline.

In quarter-mile and half-mile increments Mueller is in and out of the van, swinging the antenna around, squawk box to his ear, taking compass readings. After a few more readings he finalizes the coyote’s location in a small wetland not far from one of the many bike paths that probe south from the city. He stayed put until 2 a.m., when Mueller called it a night.

“I can’t wait,” says Mueller, thinking ahead 12 months, when he’s got hundreds of hours of data plotted on a map and can begin to see patterns. “The underlying goal of this project is to be able to coexist with these animals more effectively, to avoid conflicts,” he says. “We don’t want to have to remove coyotes from a population because they are too habituated to people.”

As a summer job during college, Mueller used to take calls at a wildlife rehab center in Milwaukee. “A lot of times people just don’t know much about the ecology and life history of these animals, and that lack of understanding leads to fear,” he says. One call in particular stuck with him, a man worried about a turkey walking around in Milwaukee.

“He said, ‘You’ve got to take it back to nature. It’s not supposed to be here,’” Mueller remembers. But the turkey had already redefined nature—and so have coyotes and foxes and deer and raccoons and . . .

“Cities aren’t going anywhere,” says Mueller. “And the way that these animals are adapting, I think it’s only going to allow for more animals to continue this trend.”

Keep up on all the latest information from the UW Urban Canid Project at their new website, http://uwurbancanidproject.weebly.com/, as well as on Facebook and on Twitter: @UWCanidProject. If you have any questions, or are interested in observing or volunteering, please email: uwurbancanidproject@gmail.com.
To see more campus fox photos by E. Arti Wulandari, visit: http://go.wisc.edu/campusfoxes.

Making It Personal

It was one of the strangest homework assignments Erin Syverson had ever had. The senior genetics major was asked to open a small vial and start spitting.

“I would much rather have gotten my blood drawn, but it’s a simple, effective way to collect DNA at home without a medical professional,” notes Syverson, who submitted her saliva to 23andMe, a private company that analyzes a person’s DNA—all 23 pairs of chromosomes, hence the name—for $99.

Syverson underwent the analysis as part of Genetics 677, Genomic and Proteomic Analysis. While DNA testing is not required for the course, professor Ahna Skop encourages her students to undergo it. Students may use their own results as the basis of their individual semester-long class project, which requires doing in-depth research about a particular genetic disease or disorder and presenting findings in class and on a website the student creates.

“Because they have a vested interest in their project, they are emotionally engaged and seek out answers from me, their classmates and beyond the classroom—for example, from doctors and their families,” says Skop. “The payoff I see in my course is deeper, longer-lasting learning due to this emotional investment.”

Those benefits are being cited all around the nation as more and more college genetics courses encourage students to get tested. They were confirmed by a recent study in the journal PLOS One showing that 70 percent of students who underwent personal genome testing self-reported a better understanding of human genetics on the basis of having undergone testing. They also demonstrated an average 31 percent increase in pre- to post-course scores on knowledge questions, which was significantly higher than students who did not undergo testing.

Syverson didn’t end up basing her research project on her own results, but she still found the testing worthwhile. “Through learning to interpret my own results and scrutinize them, I have learned a lot about not only the diseases they tested me for, but also how to think critically about genetic results,” she says. “I’ve also learned a lot about the state of the field and how to explain it to others, which will be very helpful for my future career as a genetic counselor.”

The course will be offered again next spring. Student presentations are posted at
http://gen677.weebly.com/projects.html.

Protecting our Pollinators

People and bees have a long shared history. Honeybees, natives of Europe, were carried to the United States by early settlers to provide honey and wax for candles. As agriculture spread, bees became increasingly important to farmers as pollinators, inadvertently fertilizing plants by moving pollen from male to female plant parts as they collected nectar and pollen for food. Today, more than two-thirds of the world’s crop plants—including many nuts, fruits and vegetables—depend on animal pollination, with bees carrying the bulk of that load.

It’s no surprise that beekeeping has become a big business in the farm-rich Midwest. Wisconsin is one of the top honey-producing states in the country, with more than 60,000 commercial hives. The 2012 state honey crop was valued at $8.87 million, a 31 percent increase over the previous year, likely due in part to the mild winter of 2011–2012.

But other numbers are more troubling. Nationwide, honeybee populations have dropped precipitously in the past decade even as demand for pollination-dependent crops has risen. The unexplained deaths have been attributed to colony collapse disorder (CCD), a mysterious condition in which bees abandon their hives and simply disappear, leaving behind queens, broods and untouched stores of honey and pollen. Annual overwintering losses now average around 30 percent of managed colonies, hitting 31.1 percent this past winter; a decade ago losses were around 15 percent. Native bee species are more challenging to document, but there is some evidence that they are declining as well.

Despite extensive research, CCD has not been linked to any specific trigger. Parasitic mites, fungal infections and other diseases, poor nutrition, pesticide exposure and even climate change all have been implicated, but attempts to elucidate the roles of individual factors have failed to yield conclusive or satisfying answers. Even less is known about native bees and the factors that influence their health.

Poised at the interface of ecology and economy, bees highlight the complexity of human interactions with natural systems. As reports of disappearing pollinators fill the news, researchers at CALS are investigating the many factors at play—biological, environmental, social—to figure out what is happening to our bees, the impacts of our choices as farmers and consumers, and where we can go from here.

KnowHow: How Birds Find Their Way

It’s a great biological mystery—how millions of migratory birds make epic journeys between their breeding and wintering grounds every year, rarely losing their way.

They actually use some of the same tools we do—but theirs are inborn. “Migratory birds and humans need at least a map and a compass to find their way—a map for route and distance, and a compass to stay on course,” notes Stan Temple, an emeritus professor of forest and wildlife ecology.

“Many young migratory birds are born with an innate map that gives them direction and distance to travel during migration,” says Temple. This is evident from the many young birds that make their first migration without their parents. They get a sense of direction—their compass—from environmental cues.

Other birds, such as the young of swans, cranes and some other large birds, are born with the instinct to migrate but learn a migratory route from their parents during their first migration.
”We have strong evidence of celestial cues, the earth’s magnetic fields and other environmental cues,” says Temple. “Birds use the most accurate navigational cues available at the time, often the sun and stars. When skies are overcast, birds may fall back on geomagnetic cues.”

Celestial Navigation
Birds can get a mind-boggling wealth of information from the positions of the sun and stars—patterns that constantly are changing throughout the day, throughout the seasons and from northern to southern hemispheres.

Human sea-goers use a clock, a compass, maps and a sextant to navigate by stars and sun. (The clock is essential.) Avian travelers are equipped with several internal clocks and a genetically programmed map.

Geomagnetic Navigation
Migratory birds can use the earth’s magnetic field as a compass. The earth’s magnetism is strongest at the poles and progressively weaker toward the equator. Birds may identify north-south directions by sensing differences in the strength of the earth’s magnetic field. Very recent studies have identified a region of the migrating bird’s brain that can detect magnetism.

Geographic Mapping/Landmarks
Birds learn to use landmarks—such as mountain ranges, shorelines and large lakes—from their first migration. Landmarks are most useful as a bird gets close to its destination.

Grow Fish

WITH MANY WILD FISH STOCKS in decline from overfishing and other threats, aquaculture—the managed cultivation of fish—has taken on a larger role in feeding the nation’s growing appetite for seafood. But are farmed fish really any freer from contamination than wild ones?

That all depends, says Jeff Malison, director of the CALS aquaculture program in the Department of Animal Sciences.

“No fish is going to be pollutant-free,” he says. “But yes, farmed fish can have much lower levels (of contaminants) than wild fish—at least they have that potential.”

Because farmed fish accumulate toxins from the environment and their food just like wild fish do, the key to producing a “clean animal” is to grow it in fresh, unpolluted water and feed it a diet free of toxic ingredients, Malison says. But farmed fish also have a fin up on their wild kin: They grow much faster, which means they have considerably less time to collect pollutants during their short lives. Pond-raised rainbow trout, for example, are usually big enough for the dinner plate by one year old, whereas wild trout of the same size might be three to four years old.

Wisconsin happens to be among the top 10 producers of farmed rainbow trout in the country. But before consumers rush out to buy farm-raised filets of other popular Midwest fish, such as yellow perch and walleye, they should know that fish farming is hardly routine. Malison points out that we raise only about six to 10 bird and mammal species for meat, but we eat around 200 species of fish, each with its own set of environmental needs and tolerances. And with the exception of a few species, most fish have yet to be bred for captivity.
“Even though it was practiced in China 4,000 to 5,000 years ago,” says Malison, “aquaculture is still relatively young as a technological industry.”

The aquaculture program has been working since the 1970s to improve two critical factors that limit the production of fish: reproduction in captivity and the costs of raising juveniles. The diminutive yellow perch is a prime example. Because it takes many perch to make a meal, farmers need to grow lots of them. “And when you need lots of them you’ve got to make sure the cost of the babies is really, really low to develop a profitable industry,” says Malison. “So we’ve been doing a lot of research on reproduction to try to reduce the cost of fingerling production.”

CALS researchers have also studied walleye, but for a very different reason. Carnivorous and aggressive, “it’s really kind of a rascal in captivity,” Malison says, noting that farmed walleye have a tendency to attack their own mates. To solve this problem, his group is now using Wisconsin Department of Agriculture, Trade and Consumer Protection funds to breed the brutish walleye with a closely related fish, called the sauger. The result is a much more docile fish that also grows faster.

The success of these projects will surely expand the choices consumers have at the grocery store. But another goal is to expand the state’s aquaculture industry, which also encompasses bait fish and fish for stocking lakes and rivers. And as Malison notes, Wisconsin has plenty to bring to the table—water resources, farming expertise and, of course, the market. Fish fry, anyone?

Carin Christensen

Christensen is a wilderness ranger in the largest national forest in the United States, the 17-million-acre Tongass National Forest. Covering most of southeastern Alaska, the reserve encompasses the world’s largest temperate rainforest and Alaska’s famous Inside Passage between the mainland and coastal islands. Christensen works on a variety of projects to balance the multiple uses of the forest’s resources, including planting and maintaining lichen to monitor air quality. When she’s not busy working in the Tongass, Christensen performs in a folk band called the Western Hemlock Society.

Jim Harris

Harris served as president and CEO of the International Crane Foundation until 2006, when he stepped down to spend more time on conservation projects overseas. Now a vice president for the organization, he is particularly focused on projects in China, where six of the country’s eight crane species are threatened by human development pressures. Harris believes that a narrow view of conservation too often pits people and wildlife in conflict. His work focuses on communicating the local benefits of conservation, allowing stakeholders to become allies.

Eduardo Santana Castellón

After earning his master’s degree, Santana Castellón went to the University of Guadalajara in Jalisco, Mexico, where he championed the creation of the Sierra de Manantlán Biosphere Reserve. Considered one of the most significant conservation areas in Latin America, the reserve harbors an amazing richness of life found few other places in the world, including a species of wild corn that was believed to have gone extinct. After completing his Ph.D. on the dynamics of bird communities in western Mexico’s cloud forests, Santana Castellón returned to the University of Guadalajara as part of its faculty, where he has received national and international distinctions for his conservation work.

Jim Wesson

In the Chesapeake Bay, Wesson is leading an innovative project to restore the one of the bay’s signature features: oysters. Troubled by environmental pollution, oysters filter water and create niches for other aquatic species to thrive, making them a key link in the bay’s ecosystem. As part of the Virginia Marine Commission’s Division of Fisheries Management, Wesson led a project to construct artificial reefs to help re-establish the shellfish. Young oysters are raised for a year and then transplanted onto the reefs by volunteers. Wesson was spurred to action in part by personal history. He grew up in a family of commercial blue-crab fishermen and had seen the effects of declining oyster populations firsthand.

Jerry Bartelt

As chief of the wildlife and forestry research section of the Wisconsin Department of Natural Resources, Bartelt’s charge was to provide the best possible science to guide the state’s natural-resource policies. In 15 years on the job, he and his team tackled large-scale problems such as dealing with chronic wasting disease in deer and identifying sustainable farming practices that support wildlife and the environment. Bartelt recently took a two-year leave to lead the writing of a new DNR handbook on ecosystem-management planning. He credits CALS for instilling a sense of pragmatism that guides his approach to his work.

Matt Becker

Becker is chief executive officer of the African Wild Dog Conservation Trust, where he is working to save the second-most endangered carnivore in Africa. Only 2,000 to 5,000 of the dogs remain in the wild, primarily in protected reserves, but Becker’s organization is working to preserve the species and its habitat through research, community education and cooperative conservation efforts. He’s pursued alliances with the World Wildlife Fund and authorities in Zambia, where many of the dogs survive. This isn’t Becker’s first work with endangered species: Prior to going to Africa, he studied gray wolves in Yellowstone National Park.