Tag Archives: invasive species

An Aggressive Jumping Ant With Jaws Like A Bear Trap Is Invading Southeastern U.S.

Meet the trap-jaw ant. This gnarly family of ants has massive mandibles which can open up to 180 degrees. These jaws are coated in tiny, extremely sensitive hairs, which allow the ants to snap their jaws closed faster than their brains can even process the movement (some claim they are the fastest jaws in the world).

The Odontomachus trap-jaw  ant

These formidable ants have another amazing (but rather scary) ability: when threatened, they snap their powerful jaws against the ground, creating a massive amount of force which shoots them upwards like a piece of popcorn.

With painful stingers attached to their abdomens, being surrounded by a bunch of these jumping ants could be a very unpleasant experience.

“They look like little hammerhead sharks walking around,”

said D. Magdalena Sorger, a scientist who has been studying these insects as part of her PhD research at North Carolina State University.

There are four species of trap-jaw ants native to the U.S., but Sorger’s research has focused on a particularly aggressive species of trap-jaw ants that originated in South America.

This invasive species of trap-jaw ant, known as Odontomachus haematodus, has actually been living in the States for around 50 years now, but studies have shown that the ant has been rapidly spreading along the Gulf Coast in recent years.

The invasive trap-jaw ant species Odontomachus haematodus (Courtesy of Alexander Wild)

Why are they only spreading now? Sorger isn’t sure yet, but suggests that they were either building up their numbers before spreading, or that changes in climate have allowed them to inhabit a wider range.

So, should we be worried about a trap-jaw ant takeover? That’s pretty unlikely, according to invasive ant specialist Andrew Suarez. He points out that unlike other invasive ants (like fire ants, for example), these South American trap-jaw ants,

”don’t have colonies with tens to hundreds of thousands of workers that can overwhelm the local fauna.”

He does point out that their sting is particularly painful however, and that some people may be allergic to the venom.

Read the original story from National Geographic here.

Feature image courtesy of Alexander Wild.

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2-Foot-Long American Bullfrog Sparks Concern In British Columbia (Photos)

Recently a man named Russ Schut was fishing in Sproat Lake, which is on Vancouver Island (Canada), just northeast of Washington state.

With just a worm as bait, Russ was able to haul in a 2-foot-long American bullfrog (which he released).

Russ Schut poses with massive bullfrog. Photo courtesy of Russ Schut

Schut posted this picture with the enormous frog thinking that it wasn’t particularly exceptional, other than being impressively large.

But according to GrindTV.com the photograph was noticed and has fueled concern that the,

 “…voracious amphibians are spreading unchecked across the British Columbia island’s landscape. Because they’re not native to the Canadian southwest and have few natural predators, such as alligators, water snakes, and kingfishers in their native American southeast, some of the bullfrogs are growing to abnormally large sizes.”

American Bullfrogs grow to an average length of around 7 inches and weigh up to 1.5 pounds, so the 2-foot-long Bullfrog caught by Russ Schut was defintly abnormal.

Gail Wallin works with the Invasive Species Council of British Columbia. She told Alberni Valley Times that these frogs are,

“Big and voracious…And when you’ve got a species like that, that can basically out-eat some of the native species; it will take away the forage that native species would use and at times they can be aggressive on other smaller-sized, earlier life-cycle frogs.”

A current study at the University of Victoria is mapping the rate of the bullfrogs’ spread. Wallin has theorized that they were initially introduced to the area by people emptying their aquariums, unaware of the environmental consequences.

A bullfrog with its eggs

According to National Geographic, American bullfrogs can lay as many as 20,000 eggs, with tadpoles sometimes reaching lengths of 7 inches. These bullfrogs populate quickly and with few natural predators in the area they also populate effectively. Suitably, a group of bullfrogs is called an army, or colony.

Though native to the American southwest, they now range throughout the continuous U.S., as far north as Canada and as far south as Mexico and Cuba. Their presence also has been documented in Europe, South America, and Asia.

As of now there is no plan to rid the region of the American bullfrog. Check out some images of the American bullfrog below.

New Study: Species Are Going Extinct 1,000 Times Faster Since People Arrived On the Scene

“We are on the verge of the sixth extinction… Whether we avoid it or not will depend on our actions.”

These are the words of Stuart Pimm, a well-known biologist and conservationist from Duke University. Pimm is the lead author of a new study which looked at the rate of extinction for plant and animal species, and how it has been affected by the rise of the human race over time.

Pimm has spent years researching how species emerge and disappear from our planet. He was less interested in the exact number of species that disappear every year, choosing rather to study the rate of disappearance for all species every year.

Stuart Pimm (Photo: Alex di Suvero/New York Times)

This “death rate” is simply the number of species that die out every year per million species. In 1995, Pimm had calculated the pre-human extinction rate to be 1, but further research and observations prompted him to refine this number to closer to 0.1 (meaning that only about 1 species per every 10 million total died out every year before humans emerged).

According to Pimm, that rate is between 100 and 1,000 today. There are lots of reasons for this, but it seems that by far the biggest factor is habitat loss.

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The exponential growth and spread of humans has encroached on the historical habitats of countless species, crowding many of them out.

Also, the introduction of foreign invasive species into new habitats (almost always caused by humans, whether intentionally or unintentionally), have posed another major threat to many species that were already struggling with declining habitats.

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Five times during Earth’s history, a large portion of all the plant and animal species have died out in what are known as mass extinctions. The last one, around 66 million years ago, wiped out all the dinosaurs, as well as 75% of the other species on Earth at the time.

Pimm and co-author Clinton Jenkins of the Institute of Ecological Research in Brazil believe that the rapid advancement of humans in modern times may be causing the 6th mass extinction.

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They do note, however, that modern technology has also given us invaluable tools to fight the trend, including scientific advances that help breeding programs and social media campaigns which can quickly raise awareness.

Whether we choose to actually use these tools to reverse the trend of extinctions remains to be seen.

Read more from the Post Bulletin here.

The Bright Side of the Polar Vortex: It’s Killed Off A Bunch of These Invasive Stink Bugs

The polar vortexes have brought a lot of damage, danger, and just general discomfort to people who are not used to such drastically cold conditions.

But there has been at least one positive effect of this weather. A team of entomologists at Virginia Tech lead by Thomas Kuhar has been gathering Asian stink bugs near their campus for 3 years.

The brown marmorated stink bug, properly known known as Halyomorpha halys, was mistakenly introduced in Pennsylvania in 1998 and quickly spread to 38 different states.

The brown marmorated stink bug (Photo: NPR)
The brown marmorated stink bug (Photo: NPR)

The bugs have been plaguing homeowners (they congregate in walls, shingles, and attics when it gets cold) and destroying crops across the country since they arrived in the late 90s.

The usual winter die-off rate is about 20-25% of the stink bugs, according to Kuhar and his team. This year, however they saw 95% of the population die off.

Read the full story from National Geographic here.

Feature photo courtesy of Leske, 2010.