Big Problem in the Big Easy: Invasive Cuban Treefrogs Move into Louisiana

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iStock

Louisiana is now home to one more frog species, and that's a problem. According to Popular Science, scientists have found invasive Cuban treefrogs at a New Orleans zoo, marking the first toehold the amphibians have been able to make in the U.S. outside of Florida.

Cuban treefrogs are native to Cuba, the Cayman Islands, and the Bahamas, but they came to the U.S. in the 1920s by way of the Florida Keys. They have since spread as far north as Jacksonville. The massive frogs—females can grow up to 6 inches long—are major pests, hunting several species of native Floridian frogs and out-competing others, clogging drains and setting up camp in toilets, and occasionally causing power outages when they decide to hide in utility boxes.

Now, the species is showing up in New Orleans, more than 430 miles away. They may have stowed away on a 2016 shipment of palm trees from Lake Placid, Florida bound for the elephant exhibit at New Orleans's Audubon Zoo.

A U.S. Geological Survey in the fall of 2017 captured hundreds of the frogs on and around the zoo's grounds. Over the course of four surveys, USGS scientists found 367 frogs and 2000 Cuban treefrog tadpoles. They drained the two pools where the tadpoles were swimming in the hopes of killing off any they missed, but the likelihood of reversing the spread of the frogs is low. The USGS warned in a recent press statement that "eradicating the recently discovered population in Louisiana is improbable." The frogs reproduce quickly and will eat almost anything. Based on the results of these surveys, it seems they have already driven out all the native frogs in Riverview, the section of Audubon Park where the tadpoles were found.

Brad Glorioso, the lead USGS ecologist on the study, explained that while stowaway treefrogs have trouble surviving when they make their way to higher latitudes, the climate around New Orleans seems to be more hospitable to them. "They often end up in places with unsuitable climates, but in south Louisiana, Cuban treefrogs appear capable of withstanding seasonal cold spells by seeking appropriate refuge," he said.

For now, the best scientists can hope for is keeping the frogs from moving across the river from the zoo into one of the large public nature preserves nearby.

[h/t Popular Science]

Climate Change Is Threatening Nearly All UNESCO Sites Around the Mediterranean

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iStock.com/tunart

The Mediterranean is home to some of the world's most famous cultural wonders, with 49 UNESCO-recognized world heritage sites in the region in total. Now, the organization warns that all but two of these sites are threatened by flooding and erosion linked to climate change, Artnet News reports.

For a recent study, published in the journal Nature Communications, a team of researchers looked at how various possible outcomes of rising sea levels could impact the Mediterranean coast between now and 2100. They found that even if global temperatures rise just 2°C (about 3.6°F) above pre-industrial numbers, the area's most treasured sites will still be at risk.

The places most vulnerable to rising sea levels include the Patriarchal Basilica of Aquileia, the Renaissance city of Ferrara, and the city of Venice. When it comes to erosion, Tyre in Lebanon, the archaeological sites of Tárraco in Spain, and the Ephesus in Turkey face the most pressing danger.

A handful of world heritage sites along the Mediterranean Sea, like the Early Christian Monuments of Ravenna and the Cathedral of St. James, could potentially be relocated as an extreme final option. Only two sites on the list—Medina of Tunis and Xanthos-Letoon—would be safe from the flooding and erosion spurred by climate change.

Rising global temperatures are on track to reshape coasts, not just in the Mediterranean, but around the world. In addition to historic sites, homes and airports are also under threat.

[h/t Artnet News]

New Study Reveals 'Hyper-Alarming' Decline of Rainforest Insect Populations

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iStock/jmmf

Climate change is decimating yet another vital part of the world's ecosystem, according to a startling new paper. Rainforest insects are dying off at alarming rates, according to a new study spotted by the The Washington Post. In turn, the animals that feed off those insects are decreasing, too.

In the study, published in Proceedings of the National Academy of Sciences, a pair of scientists from the Rensselaer Polytechnic University in New York and the National Autonomous University of Mexico studied populations of rainforest arthropods (an invertebrate classification that includes insects and spiders) in the El Yunque National Forest in Puerto Rico. They compared the number of insects lead author Bradford Lister found on trips in 1976 and 1977 with the number he and co-author Andres Garcia found on trips they took between 2011 and 2013.

Lister and Garcia used nets and sticky traps to collect insects on the ground and several feet above the ground in the forest canopy. They dried these captured bugs and measured the mass of their haul against the mass of insects found in the 1970s, finding that the modern net sweeps captured only an eighth to a fourth of the insects captured in the '70s. The mass of insects captured by sticky traps on the ground declined by 30 to 60 times what they were a few decades ago. They also tracked populations of lizards, frogs, and birds that live off those rainforest insects, finding that those populations had declined significantly, too, at levels not seen in other rainforest animals that don't rely on insects for food.

Tropical insects are particularly vulnerable to climatic changes, since they can't regulate their body temperature. During the time of the study, average maximum temperatures in El Yunque rose by almost 4°F (2°C). The warming climate is "the major driver" of this decline in arthropod populations, the study authors write, triggering a collapse of the forest food chain.

The paper has other scientists worried. "This is one of the most disturbing articles I have ever read," University of Connecticut entomologist David Wagner, who wasn't involved in the research, told The Washington Post, calling the results "hyper-alarming." Other studies of insect populations have found similarly dire results, including significant declines in butterflies, moths, bees, and other species. One recent study found that Germany's flying insect populations had decreased by as much as 75 percent in the last three decades. Scientists don't always attribute those population losses directly to warmer temperatures (habitat loss, pesticide use, droughts, and other factors might play a role), but it’s clear that insect populations are facing grave threats from the modern world.

Not all insect species will be equally affected by climate change, though. While we may see a sharp drop in the populations of tropical insects, scientists project that the number of insects in other regions will rise—leading to a sharp increase in crop-eating pests in some parts of the world and broadening mosquitos' geographical range.

[h/t The Washington Post]

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