In the Eastern Mediterranean, the pufferfish has arrived. And nobody’s too happy about it. The fish, also known as the silverstripe blaasop or Lagocephalus sceleratus, was first confirmed in Turkey in 2003 and has been spreading throughout the area. The problem with this unassuming fellow is that it contains tetrodotoxin, a neurotoxin that can be deadly to humans and for which there is no known antidote. Consumption of the fish has killed at least 7 people in Lebanon in the past few years, according to The Daily Star, and likely affected many more. A 2008 study found that 13 Israeli patients who ate the blaasop had to receive emergency medical attention at the hospital, where they didn’t recover for four days.

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What’s the News: After running aground last week on a remote island off the coast of South Africa, a freighter has leaked over 800 tons of fuel oil, coating an estimated 20,000 already-endangered penguins. “The scene at Nightingale [Island] is dreadful as there is an oil slick around the entire island,” said Tristan Conservation Officer Trevor Glass said in a statement. But even worse, authorities fear that the rats from the soybean-toting ship will swim to the island and destroy the bird population.

What’s the Context:

• The MS Oliva was traveling from Brazil to Singapore when it ran aground last Wednesday for unknown reasons, breaking up on Saturday and pouring some of its 1,500 tons of heavy oil into the surrounding waters.
• There are over 200,000 Northern Rockhopper Penguins (nearly half the world’s population of this species) on the Tristan Da Cunha archipelago, which includes Nightingale Island. This cleanup job is especially difficult because these islands lie 1,700 miles from the closest land, South Africa, making it much more difficult to launch a significant response—not good for birds who’re already listed on the international endangered list.
• The biggest danger to the penguins would be if if any rats make it from the ship to the island, as they can feast on baby birds unhindered. Like the birds from William Stolzenburg’s Rat Island—a gripping account of the challenges in ridding rats from infested islands—these remote birds “evolved in a world devoid of land-bound mammals,” and so are pretty much defenseless against rats.
• 80beats has covered oil spills in the past, including last year’s BP spill and its effects on wildlife.
• In that spill, the pelican was the oil-covered bird species that symbolized environmental disaster.

The Future Holds: Though a salvage tug left Cape Town, South Africa, last Thursday, the earliest it will arrive to help remove fuel is this Wednesday. With little to salvage, authorities say that cleanup is now the main task at hand. As Jay Holcomb, the director emeritus of the International Bird Rescue Research Center, told the New York Times, “Many of the birds have been oiled for over a week, which limits their chances of survival.”

Image: Wikimedia Commons / Arjan Haverkamp

What’s the News: After tracking baby gray catbirds with miniature radio transmitters, biologists found that cats were by far the #1 bird killer: 47 percent of the birds died at the paws of pet and feral felines (out of 80 percent that were killed by predators in general). This echoes some biologists’ view that cats are a destructive, human-assisted invasive species: “Cats are way up there in terms of threats to birds — they are a formidable force in driving out native species,” said one of the authors of the study.

What’s the Context:

• Previous research suggested that cats kill around 1,000 times more birds than windmills do.
• With an estimated 500 million birds killed every year by cats, felines also cause far more deaths than more spectacular (and media-friendly) events, like the 2,000 bird carcasses that recently rained down on Arkansas.
• 80beats has covered the dangers of wind turbines to both bat and bird populations.
• And this link between cats and death shouldn’t be confused with Oscar the cat, who earned fame for his abilities to sniff out death before it happened.

Not So Fast: While cats were the biggest threat to birds in this study, the lead author notes that the biggest culprit for bird deaths over all is still building collisions.

Reference: Balogh, Anne L., Ryder, Thomas B., and Marra, Peter P. 2011. Population demography of Gray Catbirds in the suburban matrix: sources, sinks and domestic cats. Journal of Ornithology. DOI 10.1007/s10336-011-0648-7 (pdf)

Image: flickr /  emilydickinsonridesabmx

Kudzu: It’s worse than you thought. The invasive plant now covers more than 7 million acres in the United States, mostly in the Southeast but not limited to there. Besides overrunning trees as it spreads like wildfire, the vine also brings another danger: In a study in the Proceedings of the National Academy of Sciences, Jonathan Hickman sounds the alarm that kudzu could cause a spike in ozone, polluting the air.

Ozone, of course, is a good thing when it’s high in our atmosphere, blocking some of the sun’s harmful radiation. But down on the surface of the planet, ozone isn’t such a good thing. It can cause respiratory problems in people and harm plants’ ability to absorb carbon dioxide; it also is a major constituent of smog.

Kudzu’s contribution to ozone levels works like this: Like other members of the pea family, or legumes, Kudzu grabs nitrogen from the air and puts it into the soil. There microbes convert nitrogen into nitrous nitric oxide, one of the pollutants that also comes from automobile exhaust. That gas escapes from the soil and into the air, and undergoes reactions that lead to the creation of ozone [Discovery News].

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In 1935, Australia introduced the cane toad to its sugar cane fields to battle beetle infestations–and the ecosystem has never been the same. The toxic toads took a liking to Australia and began spreading through the northeast, killing the native predators like crocodiles, snakes, and lizards that dined on them. A small cat-like marsupial, the quoll, was no exception. In the decades after the toads’ introduction, quoll populations in northern Australia have dipped precipitously. This year, ahead of the toads’ march into the quolls’ last stronghold, the Kimberly region, scientists have found a clever way to save the endangered marsupial: training it to detest the taste of toad so it won’t get poisoned [Los Angeles Times]. And the success of the experiment has suggested a bizarre conservation campaign.

In their research, scientists from the University of Sydney found that other predators like crocodiles and snakes can learn to avoid trouble, because one experience of snacking on a sickening poison toad is usually enough to teach them a lesson. But because the smaller quoll will die from eating a single large toad, it never learns to make that association. So the researchers decided to train the marsupials to avoid the toads using a method known as conditioned taste aversion.

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Asian carp—the giant invasive fish that have been moving up the Mississippi River for the better part of a decade–are getting close to the Great Lakes, and in fact some may have already crossed the barrier. For the lakes’ protectors, this is a near-doomsday scenario: Many fear that the ravenous carp could destroy the ecosystem by gobbling up the food that native fish depend on. This week the White House proposed a plan that would devote nearly $80 million to stopping the fish’s advance, but it’s not pleasing many people around the issue.

On one side, many environmentalists, as well as people who rely on Great Lakes fishing for their livelihood, have called on the federal government to shut down locks that connect the river to Lake Michigan. Michigan Governor Jennifer Granholm says, “The economic damage from these carp coming into the Great Lakes system would be irreparable…. They should shut the locks down until they get these other measures in place, and permanently have a solution to separating these two water systems” [Detroit News]. Granholm and other governors from the region met recently to try to craft another solution after the Supreme Court ruled that Illinois didn’t have to close the locks to stop the carp if it didn’t choose to.

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This week federal officials said they want to ban the importation of nine large and exotic snake species. The move is designed to quell the spread of those slithering reptiles that have gotten loose and thrived in Florida and especially in the Everglades, and that threaten to spread further across the country.

More than a million of these snakes—including the giant Burmese python, boa constrictors, and several kinds of anaconda—have come to the United States in the last 30 years as pets. But invariably, over the years, some slithered loose — or were released by owners who found their reptile[s] more than they could handle. Today, many thousands nest wild in Florida’s suburban yards, parks and the Everglades [Science News]. At least one of the species, the northern African rock python, is considered dangerous to humans.

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The Great Lakes are under threat from an Asian carp invasion that could wipe out fishing stocks, and with it, the lakes’ billion dollar fishery. On Friday, officials from the Army Corps of Engineers reported that genetic material from the carp had been found for the first time in a nearby river beyond an elaborate barrier system, which has cost millions of dollars and was meant to block their passage [The New York Times]. There is concern that if carp make it into Lake Michigan, they will gobble up the plankton that native fish feed on.

Officials also say that recreational boating may be affected–the carp can grow up to 4 feet long and weigh up to 100 pounds, and the massive fish will occasionally leap up and strike boaters. Since they were found to be moving up the Mississippi River in 2002, agencies have been trying everything they can think of to slow them down, including erecting the expensive electric barriers that cost around $9 million. The barriers work by sending low-voltage electric current through steel cables that are strung across the canal; this creates an electric field that’s uncomfortable for the fish and that’s supposed to prevent them from swimming across it.

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In an ironic twist, the weaponry of the fire ants that have invaded the American South is also their potential downfall. Entomologists have found that the fire ants’ venom contains chemical compounds that attract their natural foes, the parasitic phorid flies that turn ants into zombies before decapitating them.

The invasive red fire ants first came from South America by boat, and from their original disembarkation point in Mobile, Alabama, they have spread across the South, from Texas to Maryland. Their painful stings and their habit of shorting out electrical equipment make them a serious pest to humans, and biologists have been attempting to control their numbers by importing and distributing the parasitic phorid flies. But until now, researchers didn’t know how the flies homed in on the ants. So researcher Henry Fadamiro hooked electrodes up to the antennae of flies to investigate which of several stimuli prompted nerves to fire. By exposing the antennae to extracts from different ant glands and body parts, the researchers determined that juice from the venom glands got antennae buzzing [Science News].

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What’s worse than having one gigantic-but-relatively-docile python species invading Florida? Finding out that an extremely aggressive python species is moving in as well, and learning that the two species could theoretically interbreed to create a hybrid monster.

Florida wildlife officials have been concerned for some time about the 20-foot-long Burmese pythons that are thought to have been released by irresponsible pet owners and have established a thriving colony in Everglades National Park. But over the past year, four African rock pythons have also been sighted or captured in Miami-Dade county, giving biologists new cause for concern. Says herpetologist Kenneth Krysko: “They are just mean, vicious snakes…. You couldn’t get a worse python to become established. A Burmese python is just a docile snake. These things will lunge at you” [Miami Herald].

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At some point in the first half of the 20th century, a couple of ants hitched a ride on a boat and ended up on Christmas Island, an Australian territory in the Indian Ocean. And so began the rampage of the “yellow crazy ants,” creatures that have been named one of the top 100 most invasive species in the world. On Christmas Island, scientists have now declared an “invasional meltdown” of the original ecosystem [Science News].

The latest evidence: The ants are so plentiful and bothersome that they’re preventing birds from feeding on berries, and the birds are therefore failing to disperse seeds around the island.

Researcher Dennis O’Dowd explains that the long-legged yellowish ants earned the named “crazy” because when they are disturbed they run around frenetically. O’Dowd says crazy ants form large super-colonies and cover ground and vegetation in densities of around 1000 ants per square metre. “These ants are three-dimensional foragers,” he says [ABC Science]. The ants can thickly cover the forest floor and swarm up vines and plants.

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The burgeoning 150,000-snake python population in Florida’s Everglades National Park threatens crops, livestock, and native animals. And, as the July 1 story of the toddler killed by a pet python demonstrates, the snakes can also threaten human lives. The snake overpopulation began when python owners discarded their unwanted pets in the wild; now, lawmakers are pushing for legislation to combat this invasive species. Not surprisingly, there is disagreement over the best way to do it.

Florida Senator Bill Nelson, who filed a bill in February to ban the importation of Burmese pythons, told a Senate panel on Wednesday that the snakes are slithering their way into a wider geographical area. Then he explained in graphic detail how a pet python… strangled a toddler in her crib last week in a town northwest of Orlando. ”It’s just a matter of time before one of these snakes gets to a visitor in the Florida Everglades,” Nelson said [Miami Herald]. Nelson said he’s been pestering the U.S. Fish and Wildlife Service for three years to halt the growth of the snake population, but the agency has not yet taken action. In addition, an environmental scientist at the panel emphasized the need to majorly restructure the policies that regulate and control import of exotic species like the python.

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The union between the native California tiger salamander and the non-native barred tiger salamander, which was brought in huge numbers from Texas beginning 60 years ago by California bait dealers [The New York Times], has produced an alarming hybrid offspring. A new study of the hybrid’s behavior in artificial ponds serves as a reminder that invasive species can alter ecosystems in unexpected ways: in this case, by getting too cozy with the natives of central California.

 The new hybrid “superpredator” grows larger than either of its parent species, and its bigger mouth enables it to suck up a wide variety of amphibian prey, said lead study author Maureen Ryan…. Mostly on the menu are smaller pond species, such as the Pacific chorus frog and the California newt—both of which were “dramatically reduced” in population by the hybrid in the experiments [National Geographic News].

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More than 220 years since a ship wrecked on the rocks surrounding a remote Aleutian island, biologists believe they may have finally cleaned up the resulting mess. Rats have ruled the island since 1780, when they jumped off a sinking Japanese ship and terrorized all but the largest birds on the island [Reuters]. The voracious rodents feed on bird eggs and even chicks and small adult birds, and they so dominated the tiny island that it was given the name Rat Island. Biologists embarked on an ambitious effort to wipe out the rats last year, and now say they may have accomplished their task–but the campaign may have resulted in some avian casualties.

Nine months after scattering poisoned pellets across the island, biologists say they haven’t spotted any remaining rats, but they have found the carcasses of 186 glaucous-winged gulls and 41 bald eagles. U.S. Fish and Wildlife spokesman Bruce Woods said it’s unlikely carnivorous eagles ate the Rodenticide grain pellets, but they may have devoured some dead rats that had consumed them. “Eagles are scavengers of opportunity,” he said. “Rats don’t make up a big part of their diet naturally, but if meat is available, they’re going to take it” [Anchorage Daily News].

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Scientists may finally be on their way to controlling the pesky fire ants that have invaded the American South: They’re releasing swarms of parasitic flies that first turn the ants into zombies and then decapitate them. The non-native ants are at the top of scientists’ hit lists because they cause an estimated $1 billion in damage in Texas each year. The insects swarm on circuit breakers and other electrical equipment, damaging them severely. Swarms of the stinging insects can also severely injure humans and can kill smaller animals, such as calves and pets, that stumble across nests [Los Angeles Times].

Over the past ten years, Texas agricultural researchers have begun releasing several species of phorid flies, imported for this task from the South America. The flies “dive-bomb” the fire ants and lay eggs. The maggot that hatches inside the ant eats away at the brain, and the ant starts exhibiting what some might say is zombie-like behavior…. “There is no brain left in the ant, and the ant just starts wandering aimlessly. This wandering stage goes on for about two weeks” [Fort Worth Star-Telegram], says researcher Rob Plowes. Eventually the ant’s head falls off and the mature fly emerges, ready to lay its own eggs in a new round of ants.

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