Snowshoe hares are lynxes’ top prey.

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Long-Distance Lynx

Scientists are tracking these wildcats as they make epic journeys across North America

Early on a September morning in 2017, nature photographer Tim Newton was awakened by what sounded like “a herd of ravens” outside his house in Anchorage, Alaska. Newton went to the window and saw what he thought was a stray cat on the deck below. Two more ran by. Newton nearly shooed them off, but something stopped him. The creatures had black tufts sticking up from their ears. “I thought, ‘Well, that’s maybe not a domestic cat,’” recalls Newton. He was right: They were juvenile lynxes.

Newton got his camera, took some pictures, and was about to go on with his day when he heard a mewing sound. It was a mother lynx in the grass next to the deck calling her kittens! “As she called several more times, they all came out of the grass one by one,” Newton says. He began taking pictures from behind the screen door. The lynx kittens came up onto the deck, sat down, and stared at the camera trying to figure out what was making the clicking noise. Eventually, all seven kittens were on the deck, with the mother lynx standing beside them. Newton snapped a family photo.

Tim Newton is a nature photographer in Anchorage, Alaska. One early morning in September 2017, a strange sound outside his house woke him up. When Newton went to the window and looked at the deck below, he saw what he thought was a stray cat. Then two more ran by. Newton almost shooed them away, but something stopped him. The animals had black tufts sticking up from their ears. “I thought, ‘Well, that’s maybe not a domestic cat,’” says Newton. He was right: They were young lynxes!

Newton got out his camera and took some pictures. He was about to go on with his day when he heard a mewing sound. It was a mother lynx in the grass next to the deck, calling to her kittens! “As she called several more times, they all came out of the grass one by one,” Newton says. He began taking pictures from behind the screen door. The lynx kittens came up onto the deck, sat down, and stared at the camera trying to figure out what was making the clicking noise. Eventually, all seven kittens were on the deck, with the mother lynx standing next to them. Newton snapped a family photo. 

Tim Newton, [email protected]

The Lynx family portrait Newton took from inside his house in 2017

Lynx Boom

Newton is just one of many Alaska residents who have been spotting lynxes in recent years. Lynxes are medium-sized wildcats that live in the forests of Alaska and Canada, as well as in some of the lower 48 states. They are known for their tufted ears and their appetite for snowshoe hares.

Today, lynx sightings are more common because populations are pretty high, says Knut Kielland, an ecologist at the University of Alaska Fairbanks. People might be seeing more lynxes now because the wildcats are moving around looking for their next meal.

Snowshoe hares are lynxes’ favorite prey. The hare population rises and falls in a 10-year cycle. Because lynxes depend on snowshoe hares for food, lynx populations tend to follow the same pattern, but their peak lags a year or two. Hare populations peaked in fall of 2018. Soon, the hare population will crash, and after that, the lynx population will likely follow suit.

Newton is just one of many Alaskans who have seen lynxes in recent years. The medium-sized wildcats live in the forests of Alaska and Canada, as well as in some of the lower 48 states. They are known for their tufted ears.

Today, lynx sightings are more common than they used to be. That’s because populations are pretty high, says Knut Kielland. He’s an ecologist at the University of Alaska Fairbanks. People might be seeing more lynxes now because the wildcats are moving around looking for food, he says.

Lynxes’ favorite prey are snowshoe hares. The hare population rises and falls in a natural cycle that lasts 10 years. Lynxes depend on snowshoe hares for food, so their population usually follows the same pattern. A year or two after the hare population peaks, the lynx population does too. Hare populations peaked in fall of 2018, so there are a lot of lynxes this year. Soon, the hare population will fall again, and the lynx population likely will too.

Wild Studies

Daniel Cox/Getty Images

A snowshoe hare boom is an exciting time for scientists like Kielland who study the wildcats.  He’s the lead scientist of the Northwest Boreal Lynx Project. This collaboration between the University of Alaska Fairbanks, the National Park Service, and the U.S. Fish and Wildlife Service has been tracking the movement of lynx populations over the course of an entire snowshoe hare population cycle.

One of the most perplexing lynx behaviors that scientists want to understand is why the wildcats go on long-distance journeys called dispersals—sometimes traveling hundreds of miles. Scientists studying lynxes had received many reports of trappers who had caught a lynx with an ear tag or radio collar far from the place it had been tagged. But there wasn’t much data about these treks. Now, Kielland and his colleagues are working to collect data on how common these dispersals are, how far the lynxes travel, and where they go.

Conservationists could use information about the habitats the lynxes pass through to protect them. The big question, of course, is why the lynxes make these treks in the first place. Researchers hope that their tracking data will help them figure that out.

A snowshoe hare boom is an exciting time for scientists like Kielland, who study the wildcats. He’s the lead scientist of the Northwest Boreal Lynx Project. Scientists from the University of Alaska Fairbanks, the National Park Service, and the U.S. Fish and Wildlife Service work together on the project. They’ve been tracking where lynx populations have traveled over the course of an entire snowshoe hare population cycle.

Kielland’s team has some big questions about lynxes. For example, they knew that lynxes sometimes go on long-distance journeys called dispersals. The wildcats can travel hundreds of miles on these trips. Scientists studying lynxes sometimes tag the animals with an ear tag or radio collar to keep track of them. They had received many reports of trappers catching a lynx far from the place it had been tagged. But scientists don’t know much about these treks or why lynxes make them. Now, Kielland and his colleagues are working to collect data about dispersals. They want to know how common these journeys are, how far the lynxes travel, and where they go. Conservationists could use that information to protect the habitats the lynxes pass through.

Lisa Hupp/USFWS

A researcher attaches a GPS collar to a lynx. It will track the cat’s movements.

Since 2015, the researchers have trapped and outfitted lynxes with GPS collars that record their locations as they roam. The trapping and collaring typically happens in March and April. Every four hours, the collars send out data about where the lynxes are. Sometimes, the collars fall off or stop working when their batteries die. Occasionally, trappers catch collared lynxes and return the tracking devices to the scientists. Kielland and colleagues have collared about 170 lynxes since the start of the project.

Since 2015, the researchers have trapped lynxes and placed GPS collars on them. They typically do this in March and April. The collars record the wildcats’ locations as they roam around. Every four hours, the collars send out data about where the lynxes are. Sometimes, the collars fall off or stop working when their batteries die. Occasionally, trappers catch collared lynxes and return the tracking devices to the scientists. Kielland and his team have collared about 170 lynxes since the project started.

A Long Trek

The project has shown that each lynx’s movements is different. Some stick around their home range. Other lynxes go exploring—as Kielland calls it­—and then return home. But lynxes do not migrate seasonally, summering in one place and wintering in another. Instead, the ones that go the distance are more likely to travel in a one way dispersal that Kielland and his team are researching.

Dispersals are also more common than researchers knew. “What we’re finding out now is that it’s on a fairly large scale. Lots of animals do this, apparently, and they’re going really long distances,” says Kielland. For example, a collared lynx nicknamed Hobo traveled 2,174 miles from June 2017 to July 2018. “That was really quite something,” Kielland says.

Yet scientists aren’t exactly sure what the reasons are for these epic journeys. The main hypothesis is that lynxes disperse when food is scarce. But hare hunting is unlikely to explain everything about lynx movements.

“It’s still unclear to me why they would end up moving so far. You would think that they should be able to find some food eventually. They shouldn’t have to go hundreds of miles to find it,” Kielland says. He concludes that other factors are likely involved. “There are other things that go into the matter of being a lynx,” he says. Someday, the project might help reveal what those things are.

The project has shown that each lynx’s movements is different. Some stick around their home range all year. Other lynxes go exploring and then return home. But unlike some animals, lynxes do not migrate one way for  summer and back the other way for winter. Instead, the ones that make long journeys are more likely to travel one way and then stay put. 

Dispersals like this are also more common than researchers knew. “What we’re finding out now is that it’s on a fairly large scale. Lots of animals do this, apparently, and they’re going really long distances,” says Kielland. For example, between June 2017 and July 2018, a lynx nicknamed Hobo traveled 2,174 miles. “That was really quite something,” Kielland says.

Scientists still aren’t exactly sure why lynxes make these epic journeys. The leading hypothesis is that the predators disperse when food is scarce. But that probably doesn’t explain everything about lynx movements. “It’s still unclear to me why they would end up moving so far. You would think that they should be able to find some food eventually. They shouldn’t have to go hundreds of miles to find it,” Kielland says.

Use information about time, distance, and rates of speed to learn how different lynxes travel. Round your answers to the nearest hundredth. Record your work and answers on our answer sheet.

Use information about time, distance, and rates of speed to learn how different lynxes travel. Round your answers to the nearest hundredth. Record your work and answers on our answer sheet.

A lynx named Goldie left the Sukakpak Mountain area north of Wiseman, Alaska. Goldie reached the mouth of the Yukon River 66 days later. She traveled about 690 miles. How many miles per day was that?

A lynx named Goldie left the Sukakpak Mountain area north of Wiseman, Alaska. Goldie reached the mouth of the Yukon River 66 days later. She traveled about 690 miles. How many miles per day was that? 

Knut Kielland tracked a lynx that traveled a total of 700 miles in 2.5 months. Rather than dispersing, the lynx went exploring, then returned home. How far did it travel per week?

Knut Kielland tracked a lynx that traveled a total of 700 miles in 2.5 months. Rather than dispersing, the lynx went exploring, then returned home. How far did it travel per week?

A. It took a lynx named Moana 7 weeks to travel 420 miles from Wiseman, Alaska, west to Kotzebue this spring. About how many miles did Moana travel per day?

A. It took a lynx named Moana 7 weeks to travel 420 miles from Wiseman, Alaska, west to Kotzebue this spring. About how many miles did Moana travel per day?

B. If Moana traveled at that same rate for 16 days, how far would she travel?

B. If Moana traveled at that same rate for 16 days, how far would she travel?

C. Alaska measures about 2,400 miles from East to West. Traveling at this rate, how long would it take Moana to travel all the way across Alaska?

C. Alaska measures about 2,400 miles from East to West. Traveling at this rate, how long would it take Moana to travel all the way across Alaska?

A. In June 2017, Hobo—one of the first collared lynxes to go on a dispersal—traveled a total of 2,174 miles in 56 weeks. On average, how many miles did Hobo travel per day?

A. In June 2017, Hobo—one of the first collared lynxes to go on a dispersal—traveled a total of 2,174 miles in 56 weeks. On average, how many miles did Hobo travel per day?

B. After the dispersal, Hobo spent the winter in Faro, a town in Canada’s Yukon Territory. During that time, a period of 177 days, he didn’t travel at all. Use this new information to get a more accurate estimate of how far Hobo traveled per day.

B. After the dispersal, Hobo spent the winter in Faro, a town in Canada’s Yukon Territory. During that time, a period of 177 days, he didn’t travel at all. Use this new information to get a more accurate estimate of how far Hobo traveled per day.

C. If Hobo had continued at the same rate as in 4B, how many days would it have taken him to travel 150 more miles?

C. If Hobo had continued at the same rate as in 4B, how many days would it have taken him to travel 150 more miles?

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