Carnivorous Mice eating Baby Birds Alive

House mice introduced to a South Atlantic island are attacking and killing seabird chicks, such as the Tristan albatrosses.

http://www.livescience.com/animals/070706_mouse_thugs.html

Gangs of house mice have been caught attacking and killing seabirds 300 times their weight on an island in the South Atlantic Ocean.

House mice (Mus musculus) were thought to pose little risk to island birds, until now. Now, video footage exposes tiny house mice as they invade the nests of young chicks and proceed to gnaw through chicks' feathers and skin before gorging on their entrails.

The result is more than a tale of mighty mouse gone bad; with so many chicks dying and not making it to adulthood (an age when they can breed), the island's bird populations can take a nosedive.

While islands represent a small fraction of Earth's land area, they are home to a relatively large percentage of bird species. Since 1600, more than 90 percent of avian extinctions have occurred among island species, say the authors of the new study.

Many of the extinctions have been blamed on invasive mammals, particularly rats. Conservation efforts, therefore, have focused on eradicating the non-native rats from such islands. Mice, on the other hand, had been deemed to pose no threat to seabirds and left to populate islands sometimes without competition from their rat relatives.

That's the case on Gough Island in the South Atlantic, where mice are the sole introduced mammals. Turns out, that's a morbid recipe for the local birds.

Mouse attacks

Between January and September 2004, Ross Wanless of the University of Cape Town in South Africa and his colleagues monitored 300 Tristan albatross (Diomedea dabbenena) nests. They examined chicks for wounds about three times a month and filmed chicks using an infrared video recorder.

They also monitored and video recorded three great shearwater (Puffinus gravis) and 60 Atlantic petrel (Pterodroma incerta) chicks.

Mice were caught on video gnawing on and often killing live chicks of all three bird species. One video showed up to 10 mice mauling an albatross chick and eating from three open wounds on its body.

The scientists describe a brutal attack to illustrate the finding that chicks didn't seem to fight against the attackers. "No chicks displayed appropriate behavioral responses to attacks, even though mice had eaten through the body wall of one filmed albatross chick and were consuming the contents of the chick's abdominal cavity," they write in a report of the research published in the journal Biology Letters.

By late September 2004, 100 of the 256 monitored albatross chicks had died. Before the mouse attacks, all the chicks were apparently healthy, suggesting the rodent thugs didn't target weak or sick individuals.

Bird conservation

At the end of the study, the researchers calculated a breeding success of just 27 percent for the albatross, which is "unprecedented" for this species. Typically, about 60 percent to 70 percent of the chicks survive.

Mice also wreaked havoc on the Atlantic petrel chicks as soon as the babies hatched in July 2004, and by September 2004, just 20 of the 60 monitored chicks were still alive.

The scientists speculate that on islands where house mice are just one part of a network of invasive species, including rats, they pose less of a threat to seabirds compared to larger predators. But on six islands where house mice are the sole invasive mammals, Wanless said, scientists should study the effects of mice on seabird breeding successes.

Category:

Pets & Animals

Tags:

• mice
• carnivore
• gross

[SafetyChris]

that chick doesn't seem interested in the fact it's being eaten alive

[nanigina]

my god....... its a cool vidoe... but i feel ver sorry for the bird

[turamba]

@DJBrokenHigh it's only a baby bird, not a falcon ;)

[Sbisbee3]

@MahlerTitan but doesn't getting eating alive hurt? Id think it wuld at least move/try to walk away if it cant fly.

[aceg81]

Mice and baby birds. That's simultaneously the cutest and most horrifying video I've ever seen :-P

[Spring1234777]

@SafetyChris baby birds dont have a lot of mobility...and also, why do predators always start at the butt.... :/

[DJBrokenHigh]

Fight back you dumb bird

[jeclairm]

@MahlerTitan What? Mice are omnivores. They commonly eat each other even if given the opportunity. Mothers eat their babies if there isn't enough food around or they feel like they have too many. Have you ever had pet mice? I've even seen mice, dead in traps, half eaten by other mice. Introduced rats and mice like these have caused havoc across much of the south pacific and many species have gone extinct already. Without control, these birds will as well.

[SmilingMelvin]

Very educational video. I was not aware that an albatross's asshole was good to eat. Guess you learn something new every day!

[themousemaster]

WOW JUST WOW! but why doesn't it fight back? or a least move? do they not move at that age if not where is it's mother? and why don't the guy save it instead of talking about it getting eaten

[The14Pugs]

0:02 Epic eye nibble.

[Akira625]

@MahlerTitan Much like the dodo, they had no natural enemies, therefore had no fear of the humans who hunted them to extinction. Had they feared them, it would've triggered a flight or flight response could have given them at least a fighting chance at survival. Even more unfortunate, dodos never had a chance to evolve to where they could develop some sort of defense that could be passed on to their descendants, as they were all wiped out less than a century after man first encountered them.