Could weather patterns help predict the frequency of rattlesnake bites?

SALT LAKE CITY — Nature is full of all manner of surprising relationships that challenge us. As naturalist John Muir observed, "When we try to pick out anything by itself, we find it hitched to everything else in the universe."

Nature's web binds creatures and circumstances together that couldn't seem more different. Hummingbirds are one example — they are among the most beloved birds on the planet, but few people realize that they rear their young swaddled in nests made of spider silk.

It's something to think about this Halloween season, as faux spiderwebs and, perhaps, some real ones abound in spooky seasonal displays.

Hummingbirds are hardly the only example of nature's peculiar pairings. A growing body of research has discovered a probable connection between rattlesnake bites and the West's most valuable resource — water.

Utah, like its sister states, has recently labored under a prolonged and oppressive drought. As recently as 2021, Utah's governor encouraged the people of Utah to pray for rain.

In 2023, relief finally came — in a big way. Utah's 2023 winter snowpack smashed records, and the resulting runoff granted the arid state a new lease on life and a chance to recuperate severely dwindled water stores. The trend has continued, though, at a reduced and somewhat inconsistent pace in 2024.

But what does snowpack and precipitation have to do with rattlesnakes?

There have been an unprecedented number of rattlesnake encounters on Utah's trails this year. On one day in particular, within one hour of hiking along a trail I've traveled more than 100 times in the past decade — I matched the total number of previous rattlesnake encounters.

While anecdotal, to be sure, my experience is hardly isolated. At the same time Utah was celebrating record snowfall, California was also "getting pummeled" by intense rain and snowstorms.

The record moisture led to an explosion of vegetation and abundant food for rodents — a favorite menu item for rattlesnakes. According to the owner of one snake removal company in California, with more abundant prey, rattlesnakes can become "bolder and more active." This claim is seemingly supported by a study of snakebite frequency, which shows the number of bites rose and fell in relation to periods of drought and no drought.

Researchers then concluded, "Patterns of precipitation and drought had a significant and predictive effect on snakebites in California."

But, is the same true in Utah?

"We don't have the data to support whether or not there is an increase in rattlesnake activity following previous years of better-than-average precipitation and snowpack in Utah. However, food availability would have an impact on rattlesnake behavior, especially in years where there may be an increase in small rodent populations," said Alyssa Hoekstra, herpetology coordinator with the Utah Department of Wildlife Resources.

She explained the resulting increased rattlesnake activity wouldn't be immediate following a storm. "Typically you would see it delayed a season or two when rodent populations increased with increased vegetation," Hoekstra said.

She said the greater abundance of food would also "lead to activity such as mate searching" among rattlesnakes, potentially making them more visible.

While state wildlife managers don't have data to directly tie increased rattlesnake activity to precipitation patterns, Hoekstra said, "It would be a good hypothesis for why we would see an increase in rattlesnake activity."

As studies in California suggest, there is little evidence in Utah to show that the number of snakebites increases after heavy snowpack or precipitation.

Not every snake envenomation is reported to Utah Poison Control, however, so data is incomplete, said Amber Johnson, director at Utah Poison Control.

Interestingly, 2012 saw the greatest number of reported rattlesnake bites — 36, to be exact. That year also happened to be the year following the winter of 2011 — one of the heaviest snow seasons in recent memory.

But what of 2024? After the record-shattering winter of 2023, is there evidence that snakebites saw a noticeable increase?

With potentially more bites to come (bites can occur as late as December), it's difficult to know where the 2024 calendar year will end. But thus far, there have been 24 rattlesnake bites reported to Utah Poison Control this year, Johnson said, adding the yearly average from 1997 to the present is 25 bites.

Whether sufficient data will ever be compiled to definitively link snowfall and precipitation to rattlesnake bites in Utah is unclear. But there is good reason to seek a more than superficial understanding of the natural world and nature's surprising connections.

While spiders and snakes commonly top lists of the creatures people fear most, both are valuable natural mechanisms that regulate bug and rodent populations.

"Rattlesnakes help maintain a balance," said Hoekstra. Beyond regulating rodent populations, she said rattlesnakes help regulate the diseases rodents sometimes carry, including Lyme disease, by consuming both the rodents and the ticks living on the rodents.

The study of their venom has led to breakthroughs in medical research and helped create medicines to benefit humans.

These "creepy crawlies" perhaps don't have the most glamorous job and they aren't likely to win many beauty contests — but the work they do is vital, nonetheless.

Little wonder that rattlesnakes are protected, according to the Utah Division of Wildlife Resources. If you encounter a snake on the trail or in the backcountry, Hoekstra advises leaving it alone.

"Give it a wide berth and continue on your way," she said. "The best thing for people to do is just to be aware of what animals they can encounter."

If you or someone you know does get bit, Johnson advises, "Always stay calm." Remove any rings, jewelry, or tight clothing near the bite site before swelling sets in and "seek medical help as soon as possible."

Marking the bite site with a pen and making note of the time can also be very helpful.

Johnson further advises against using any kind of bandage, wrap or suction on the bite sight, or attempting to cut the wound open to extract the venom. Doing so can "concentrate the venom leading to further tissue damage," she said, adding that the most important thing one can do is get "a medical evaluation as soon as possible to make sure you don't need additional treatments like anti-venom."

Speaking of personal experience, I've had a few very close calls recently. Fortunately, I've emerged from each encounter unscathed.

Having accidentally come within biting range on more than one occasion, I can attest that rattlesnakes prefer to avoid conflicts when given a chance and very rarely bite without provocation. Still, it's best to give them plenty of space and know how to respond should the need arise.

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