Advertisement
  1. News
  2. /
  3. Environment

Hurricanes may spin a more aggressive population of spiders, new study shows

The study suggests storms make spiders more active in protecting their nests, and they pass the trait down.
New research shows that the more aggressive the Anelosimus studiosus spider is, the better chance they’ll survive a hurricane. [Special to the Miami Herald] [Special to the Miami Herald]
Published Aug. 22
Updated Aug. 22

This story was written by Alex Harris, climate change reporter for the Miami Herald.

If you live in Florida, you know the psychological toll hurricanes have on humans. We panic, we obsess over the latest weather report, we rant about horrendous evacuation traffic.

What’s far less known is the effect of hurricanes on non-human residents. One new study shows storms have a surprising evolutionary impact on spiders — producing a more aggressive population of arachnids.

That’s the conclusion of a paper published Monday in Nature Ecology & Evolution, which found that aggressive spider colonies survive and reproduce better after storms than docile ones, a finding based on a series of storms that made landfall in Florida and Georgia. The study is part of an emerging field of research aimed at understanding how climate change can alter the way wildlife and bugs evolve. Another hurricane-specific study last year found that lizards with longer legs do a better job of surviving hurricanes.

“The impact of these storms on wildlife are mostly a big question mark on our white board,” said one of the paper’s authors, Jonathan Pruitt. “Hurricanes could be shaping that evolutionary history of animals and we don’t even know.”

New research shows that the more aggressive the Anelosimus studiosus spider is, the better chance it will survive a hurricane. Their cobwebby nests can be anywhere from golf ball sized to basketball sized. [Special to the Miami Herald] [Special to the Miami Herald]

Predicting where storms will hit (and getting there in enough time to collect usable data) is difficult work. It’s part of the reason why scientists say research on the evolutionary impacts of hurricanes on specific wildlife populations is challenging. Most studies tend to focus on mortality or habitat loss — the immediate aftereffects.

RELATED STORY: Scientists coax imperiled Florida coral to spawn in a lab for the first time

The latest study from Pruitt — research chair in the department of psychology, neuroscience and behavior at McMaster University in Ontario, Canada — focused on how one type of bug adapts and survives.

The study included data from three 2018 storms, Tropical Storm Alberto, Hurricane Florence and Hurricane Michael, with most of the research spots in Florida. In each case, Pruitt had to try to predict where a storm would hit and rush over to find out what the spider population was like before a storm. Then he’d wait it out in a hotel room for a couple of days before heading back out in his F-150 truck to check on his spiders.

“The largest bugaboo about this research is coming back to these sites after the storm,” Pruitt said. Luckily, the Floridians and Georgians he ran into were happy to break out their chain saws and carve him a path to the spiders.

Pruitt focused the research on Anelosimus studiosus, a tiny, saffron-colored spider with a ruffled pattern on its globe-shaped behind that lives in the Eastern U.S. He called them “junk spiders” that make their cobwebby nests, which can be anywhere from golf ball-sized to basketball-sized, over water.

RELATED STORY: How green is Ron DeSantis on climate change? We ask because...

How can you tell if a spider is more aggressive? You use “a vibrating narwhal,” as Pruitt puts it.

“Traditionally we use a vibrator, but for this I used a mechanical toothbrush,” he said.

He wrapped the toothbrush in wire until it had a point sticking out (like a narwhal horn) that he used to gently poke a piece of paper he stuck to the spider web, making the paper flutter like a trapped insect.

“The spiders find that irresistible,” said Pruitt.

If the spiders rushed out to defend their web immediately, Pruitt called them aggressive. If they hung back a bit, he categorized them as docile. He found that areas that were often hit by storms had more aggressive spider populations, compared to less vulnerable areas. Those aggressive spiders did a better job of having babies and keeping those babies alive — making hurricanes a form of natural selection favoring more combative arachnids.

One of the first studies to talk about the impact of hurricanes on wildlife was published in Nature last summer. It involved lizards — and a leaf blower.

RELATED STORY: Florida newsrooms band together to cover the effects of climate change

Lizards with longer arms and bigger toe pads, researchers found, were more likely to survive the hurricanes that battered Turks and Caicos in 2017. In a case of making lemonade out of lemons, the researchers from Harvard University and the Paris Museum of Natural History didn’t originally intend to study the effects of storms on the local lizard population, but Hurricanes Irma and Maria changed their plans, said one of the authors, Harvard post-doctoral fellow Colin Donihue.

Researchers found that long-legged lizards with bigger toepads survived hurricanes better than their short-legged brethren. [Special to the Miami Herald] [Special to the Miami Herald]

“A really novel twist to Jonathan’s study is he actually went down and anticipated where hurricanes were going to hit and went down and got the data,” he said. “My data collection was entirely serendipitous.”

Donihue and his team wrapped up their initial research four days before Hurricane Irma hit in September, which was quickly followed by Hurricane Maria. That’s when they decided to come back six weeks later and see what happened to the lizards.

The end of the field work left them with plenty of questions and no guarantee of another storm, so the scientists decided to rig up a high-powered red leaf blower and a camera to capture exactly what happens when these lizards encounter high winds.

The result: riveting photos and videos of the tiny reptiles hanging on for dear life, and a better understanding of how they survive hurricane force winds.

“There’s really been very few studies that document any non random mortality or natural selection,” Donihue said. “It’s something we just completely overlooked, well, forever.”

The work done by Donihue’s team has set off “a little flurry of interest” among other scientists, he said. They’re all trying to find out the evolutionary impacts of hurricanes, especially as research shows climate change could be making storms stronger. He and Pruitt are both continuing to research what happens to wildlife after storms, and they hope other scientists will too.

“Extreme climate events, hurricanes specifically, could have really important consequences for all the species on the planet and not just as mortality events but as readjustment to evolutionary trajectories,” Donihue said. “As hurricanes become more severe in the future it could have an even more severe impact than we know of now.”

This story was produced in partnership with the Florida Climate Reporting Network, a multi-newsroom initiative founded by the Miami Herald, the South Florida Sun Sentinel, The Palm Beach Post, the Orlando Sentinel, WLRN Public Media and the Tampa Bay Times.

ALSO IN THIS SECTION

  1. Waves crash in front of an American flag that is planted on a jetty during a high surf from the Atlantic Ocean, in advance of the potential arrival of Hurricane Dorian, in Vero Beach on Sept. 2. GERALD HERBERT  |  AP
    Their efforts underscore the risks of a warming planet for the state’s future.
  2. Florida Gov. Ron DeSantis talks to reporters in Tampa on Aug. 21. Delays in his filling vacancies on the state's five water management district boards have twice led to those agencies canceling meetings to levy taxes and set budgets, which one expert said was unprecedented. OCTAVIO JONES   |   TIMES  |  Times
    Vacancies lead to canceling two agencies’ budget meetings.
  3. Reclaimed water rates are increasing 6 percent in St. Petersburg.
    Potable, waste and reclaimed water fees will all increase. So will garbage fees, though the stormwater fee will drop for some.
  4. In this Sept. 13, 2019 file photo, young climate activists march with signs during a rally near the White House in Washington. At left is the Washington Monument. In late September 2019, there will be climate strikes, climate summits, climate debates, a dire climate science report, climate pledges by countries and businesses, promises of climate financial help and more. There will even be a bit of climate poetry, film and music. (AP Photo/Susan Walsh) SUSAN WALSH  |  AP
    Organizers expect millions to take part in marches, rallies and sit-ins for what could be the largest ever mass mobilization on climate issues.
  5. Trash collects in JoeÕs Creek Watershed, Pinellas Park Ditch, on  Sept. 17, 2019 in Pinellas Park. The grasses and sediment acts as camouflages for an alligator to the right of the trash.  TRACEE STOCKWELL   |   TIMES  |  Tampa Bay Times
  6. Neighbors had objected to the Lago Verde mine in north-central Pasco and then the adjoining Seven Diamonds LLC mine for the past seven years. The Seven Diamonds mine is now adding 60 additional acres to increase in size by one-fifth.
    The Seven Diamonds LLC mine is adding 60 acres, increasing in size by one-fifth.
  7. An man wades through flooded streets with bags of groceries in the Shore Acres neighborhood of St. Petersburg during Tropical Storm Colin in 2016. LOREN ELLIOTT  |  Loren Elliott / Tampa Bay Times
    The city plans to adjust its stormwater billing so homeowners with the most impervious surface area pay the most.
  8. A tegu lizard belonging to the Florida Fish and Wildlife Conservation Commission is displayed during a press conference. Tampa Bay Times (2014)
    The invasive lizards, which can reach five feet in length, are well established in east Hillsborough.
  9. Rendering of the new Shore Acres Recreation Center that will replace the current structure at 4230 Shore Acres Blvd. NE, St. Petersburg Wannemacher Jensen Architects
    The long-desired project is praised, but some neighbors worry about its proposed height and a new entrance and exit on busy 40th Avenue NE
  10. An administrative judge said a Pasco County ordinance allowing solar farms in agricultural districts did not violate the county's comprehensive land-use plan. Times
    An ordinance did not violate the county’s land-use plan that is supposed to protect rural Northeast Pasco, a judge said.
Advertisement
Advertisement
Advertisement