Earth’s temperatures are getting warmer. In fact, sixteen of the seventeen hottest years on record have occurred since the year 2000. These warmer temperatures are driving larger, long-term changes in our planet’s weather and climate. Scientists refer to these changes as “climate change.”
In a few places, climate change might be welcome, but around the world, warmer temperatures and other changes are leading to a host of problems from rising sea levels to more extreme weather events and the spread of harmful human diseases.
Professor Scott Mills, from the University of Montana, wanted to see how climate change might be affecting one particular animal called the snowshoe hare.
Snowshoe hares live in regions of North America that receive snow every winter. The hares, in fact, change their coat color from brown to white and back again every year. This helps camouflage them against their background—and hides them from the eyes of lynx, owls, and other hungry predators.
Here’s the thing: snowshoe hares can’t choose when they molt, or change their coat color. Molt timing is controlled by their genes, which are part of the DNA inside their bodies. If a hare’s genes make it molt to white in October, but snow doesn’t fall until December, the hare will stick out like a light bulb against the brown earth. And that’s a problem. Why? Because almost everywhere on earth, the length of time with snow on the ground is growing shorter and shorter.
To find out if shorter winters might harm hare populations, Scott and his team spent three years tagging and following hares. They measured how many were born, how many died, and what they died from. They also recorded whether the hares were matched or mismatched against their backgrounds.
They discovered that predators killed mismatched hares significantly more often than hares whose coats match their backgrounds. Scott and his team also calculated that over the next one hundred years, this greater mortality, or death rate, could lead to the decline or disappearance of many snowshoe hare populations.
The good news? Different hares molt at different times. This may help some hare populations adapt to shorter winters and longer periods without snow.
Hares are not the only animals affected by shorter winters. More than twenty species of animals including lemmings, weasels, hamsters, and Arctic foxes change their coat colors every year. Scott’s research helps us predict what might happen to these animals—and decide what we can do to protect them.
Scott’s discoveries about Montana snowshoe hares, together with experts’ predictions about our future climate, indicate that hares will be mismatched between 5-½ and 10 weeks by the end of this century.
Before tagging and putting a radio collar on a snowshoe hare, Professor Mills and his team must weigh and measure it.
This snowshoe hare has been tagged and fitted with a radio collar—and is now ready to help scientists learn more about snowshoe hare survival.
Even from a great distance, a mismatched hare stands out like a glowing light bulb. (Photo Courtesy of L. Scott Mills research laboratory)
Besides serving as popular prey for predators, snowshoe hares are irresistibly cute. This is a young hare, also called a leveret.
Sneed B. Collard III is the author of more than eighty award-winning books, many focusing on science and the natural world. His entertaining memoir Snakes, Alligators, and Broken Hearts—Journeys of a Biologist’s Son recounts his challenges and adventures growing up as the son of divorced biologist parents, and the experiences that would one day lay the foundation for his writing career. He is a dynamic speaker and offers school and conference programs that combine science, nature, and literacy. To learn more about him and his talks, visit his website, www.sneedbcollardiii.com.
This book was reviewed by Vicki Cobb in the Huffington Post: "The Cheeseburger of the Forest".
MLA 8 Citation
Collard, Sneed B., III. "Hopping Ahead of Climate Change." Nonfiction Minute, iNK Think Tank, 15 Nov. 2017, www.nonfictionminute.org/hopping-ahead-of-climate-change.
Are skunks aggressive, dangerous animals? Or are they peaceful animals that try to avoid trouble? Well, biologists who study skunks think of them this way: if life were a sport, skunks would be known for their strong defense and for playing fair.
Skunk stinkiness comes from a chemical weapon called musk. Foxes, weasels, and some other mammals also produce musk, but skunk musk is especially strong and long-lasting. And only skunks use musk to defend themselves from attack.
Picture a skunk ambling along in the night, looking for food. It digs in the soil to get tasty earthworms and beetle grubs. The black and white fur that comes with just being a skunk sends a warning. This color pattern is unusual among mammals. It signals: "Beware, don't mess with me!"
Suppose a coyote or other predator ignores this first warning. It steps toward the skunk. When a skunk feels threatened, it faces the danger. It raises its tail and tries to look as big as possible. It stamps its feet and clicks its teeth together. It may growl or hiss.
Oh, oh! Despite all of these warnings, the coyote growls and comes closer. Now the skunk gets really serious. It twists its body into a U-shape, so it can see the coyote and also aim its rear end toward it. The skunk's tail arches over its back, away from its rear—the final warning. This gives the skunk a clear shot, and also protects its own fur from the stinky musk. Skunks try to avoid smelling bad!
From two grape-sized glands, a skunk can spray musk as a fine mist, or squirt a stream. It can squirt accurately for about 12 feet (3.7m), and hit an attacking animal right in the face. The musk stings the predator's eyes, and can blur its vision for a while. And it stinks! Animals hit with this musk learn to never bother a skunk again.
A skunk's glands store enough musk to fire a half dozen shots but then need a week or so to produce more. This is seldom a problem, since a skunk sprays only when its life seems to be in danger. Some skunks can go for months or even years without spraying musk. That's fine with them. Skunks want to avoid trouble, and "play fair" with their many warnings.
A skunks’s stripes point to where the spray comes out. A 2011 study found that animal species that choose fight over flight when faced with a predator often have markings that draw attention to their best weapon. So while a badger has stripes on his face to highlight his sharp teeth, skunks’ stripes are perfectly positioned to highlight their ability to spray potential threats. By http://www.birdphotos.com via Wikimedia Commons
Skunks are so nice that some people want to keep them as pets. The striped skunk is the most social skunk and the one most commonly domesticated. The legality of keeping skunks as pets in the US varies by state, with it being illegal in a majority of them. By Matt MacGillivray via Wikimedia Commons
Larry Pringle has written many animal books, among them The Secret Life of the Red Fox. His The Secret Life of the Skunk will be published by Boyds Mills Press in 2019. It is about spring and summer in the lives of a mother striped skunk and her kits.
ML 8 Citation
Pringle, Laurence. "How Skunks Play Fair." Nonfiction Minute, iNK Think Tank, 8 Nov. 2017, www.nonfictionminute.org/how-skinks-play-fair.
We give 'em reading that gets 'em talking!
Learn from many voices....