Wild Things

The weird and wonderful in the natural world

Sarah Zielinski

Wild Things


Wild Things

Rabbits leave a mark on soil long after they are gone

European rabbit

The European rabbit looks harmless, but in the Kerguelen Islands, the species became invasive. A new study finds that the effect of the rabbits on soil fungus lasts even long after they are gone.

Sponsor Message

The remote Kerguelen Islands may be beautiful, but they are unlikely to top anyone’s list of vacation destinations. For one, the weather is awful. Located in the far southern Indian Ocean, the islands’ average highs barely top out at 11.5° C (about 50° F) even in the summer. It rains, snows or sleets for 300 days a year. And sustained winds of 150 kilometers per hour (93 mph) are not uncommon. Transportation to the islands would be another issue — there are no airports, and all people and supplies have to come by ship.

Today, the islands, discovered in 1772 by the French, are home to a small band of scientists and engineers. But in the past, they were a stopping off point for ships on whale- and seal-hunting expeditions, and a company once tried to set up a coal mining operation there. At various times, inhabitants tried to make the islands more hospitable by introducing animals or plants from home. And in 1874, someone brought European rabbits, probably thinking they’d make for tasty meals.

But without any predators around, the rabbits did what rabbits do — reproduced like crazy and ate lots of vegetation. Some native plants, such as the cushion plant Azorella selago, declined while others, like the buzzy burr (Acaena magellenica), became dominant. Bunny burrows made land more susceptible to erosion, and the changes to the soil helped invasions by non-native plants.

Johan Pansu of the University of Grenoble in France and colleagues were curious about the effect of the rabbit invasion on soil fungi, which are part of a healthy soil community. They chose three of the Kerguelen Islands to study: Grande Terre, where rabbits occur in high density in many places, such as the study site of Isthme Bas; Ile Guillou, where rabbits were eradicated in 1994; and Ile Australia, which has never had any rabbits. They collected soil samples and looked for fungal DNA. The results of their study appear September 2 in Biology Letters.

The fungal communities of Ile Australia and Isthme Bas were very different, reflecting the differences in their plant communities — Ile Australia had plenty of natives; Isthme Bas had mostly buzzy burr and non-native dandelions. But even 20 years after the rabbits had been eliminated on Ile Guillou, both the plant and fungal communities still looked like that of Isthme Bas.

“We suggest that the current status of fungal communities on Ile Gillou reflects slow recovery of the native vegetation following rabbit eradication,” the researchers write. That might be because native plants, such as the cushion plant, are slow growers, the team notes. Or there could have been changes to the climate or soil (perhaps by the rabbits themselves) that resulted in the land becoming more hospitable to dandelions than anything else.

Invasive species, it appears, can have long-lasting effects on landscapes, even decades after we have taken the trouble to try to clean up our introduced mess.

Animals

Some jellyfish sting deeper than others

By Sarah Zielinski 12:20pm, September 1, 2015
A new study shows that some jellyfish have nematocysts that can sting deep into the skin. That may explain why their sting is so painful.
Animals,, Ecology

Coral competitor becomes ally in fight against starfish

By Sarah Zielinski 1:00pm, August 28, 2015
On the reef, algae compete with coral. But they may also protect coral from attacks by crown-of-thorns starfish, a new study finds.
Animals

A world of mammal diversity has been lost because of humans

By Sarah Zielinski 9:55am, August 26, 2015
Humans have eradicated large mammal biodiversity in most regions of the globe, a new study finds.
Plants,, Animals

What fairy circles teach us about science

By Sarah Zielinski 6:30am, August 20, 2015
Science can’t yet tell us how fairy circles form, but that’s not a failure for science.
Animals,, Conservation

A UFO would stress out a bear

By Sarah Zielinski 12:00pm, August 13, 2015
Scientists need to know how animals, such as bears, react to the drones being used increasingly to study them.
Animals,, Conservation

Cougars may provide a net benefit to humans

By Sarah Zielinski 3:27pm, August 12, 2015
Cougars have disappeared from the eastern United States. If they returned, they’d kill deer, preventing many car crashes, scientists find.
Animals,, Conservation

Gibbons have been disappearing from China for centuries

By Sarah Zielinski 4:00pm, August 6, 2015
Gibbons are now found in only a small area of southwestern China. But they once thrived across much of the country, records show.
Animals

Don’t let Cecil the lion distract from the big conservation challenges

By Sarah Zielinski 4:11pm, August 4, 2015
Cecil the lion’s death rocketed across the news and social media. But there are bigger conservation challenges that need attention, too.
Animals,, Ecology

How bears engineer Japanese forests

By Sarah Zielinski 1:00pm, July 31, 2015
In Japanese forests, black bears climb trees, breaking limbs. Those gaps in the forest provide light to fruiting plants, a new study finds.
Animals,, Plants

On the importance of elephant poop

By Sarah Zielinski 4:57pm, July 28, 2015
Asian elephants are key dispersers for tree seeds. A new study finds that buffalo and cattle can also disperse the seeds, but not nearly as well.
Subscribe to RSS - Wild Things