Ravens Can Hold Grudges for Weeks, Study Finds

iStock
iStock

Never cross a corvid. Crows have been known to hold grudges, and research says that ravens do, too. A new study in Animal Behavior spotted by The Verge finds that ravens remember the nature of their interactions with humans and can remember how the experience went for up to a month afterward.

The study, which was conducted by researchers at the University of Vienna and Lund University in Sweden, presented ravens with two types of interactions with human experimenters: some that could be considered fair and others unfair.

The nine ravens had all been hand-raised in captivity by humans. (The paper delightfully includes their names, which are: Laggie, Tom, Nobel, George, Horst, Louise, Joey, Rocky, and Paul.) The birds were trained to exchange a low-quality food (bread) for something they liked more (cheese). The ravens had to take a risk in giving the human their snack, though. They could give away the bread and receive cheese in return, but there was always the chance that they would give away their bread and not get anything back.

In the experiment, each bird was given many opportunities to exchange its bread pieces with a human trainer. Another bird looked on, but couldn't participate. In some sessions, the participating bird interacted with a person who always gave them cheese in exchange for their bread. In other sessions, they interacted with a person who took their bread but ate the cheese themselves—an unfair exchange.

Later, the researchers tested whether the birds would show a preference for the person who had always been fair in their interactions. A month later, eight of the nine birds chose to trade with the experimenter who had previously shown themselves to be fair in their interactions over an experimenter who had cheated them in the past (the ninth chose a third, neutral experimenter). However, this only applied to the birds’ first-hand experiences. The birds who observed another bird’s fair or unfair interactions as a third party did not seem to remember who could be trusted and who could not.

Considering crows’ abilities to remember the people who slight them, it’s not terribly surprising that their raven cousins would be able to, too. Nor is it their only complex skill: Corvids can also use tools and practice self-control. Both of which should worry you if you make a habit of making ravens and crows mad.

[h/t The Verge]

Fish Tube: How the 'Salmon Cannon' Works and Why It's Important

PerfectStills/iStock via Getty Images
PerfectStills/iStock via Getty Images

If you’ve been on the internet at any point in the past week, you’ve certainly come across footage of wildlife conservationists stuffing salmon into a giant plastic tube and shuttling them over obstacles. It’s so bizarre—even by the already loose standards of the web—that it briefly ignited discussions over fish welfare, its purpose, and the seeming desire of people to be similarly transported through a pneumatic tunnel into a new life.

Naturally, the “salmon cannon” has a mission beyond amusing the internet. The system was created by Whooshh Innovations, a company that essentially adopted the same kind of transportation system featuring pressurized tubing that's used in banking. Initially, the system was intended to transport fruit over long distances without bruising. At some point, engineers figured they could do the same for fish.

The fish payload is secured at the entrance of the tube—acceptable species can weigh up to 34 pounds—and moves through a smooth, soft plastic tube that conforms to their body shape. Air pressure behind them keeps them moving. The fish are jettisoned between 16 and 26 feet per second to a new location, where they emerge relatively unscathed. Because there’s no need for a water column, the tubing can cover most terrain at virtually any height.

The tubing solution is a human answer to a human problem: dams. With fish largely confined to still bodies of water thanks to dams and facing obstacles swimming upstream to migrate and spawn, fish need some kind of assistance. In the past, “fish ladders” have helped fish move upstream by providing ascending steps they can flop on, but not all fish can navigate such terrain. Another system, trapping and hauling fish like cargo, results in disoriented fish who can even forget how to swim. The Whooshh system, which has been in used in Washington state for at least five years, allows for expedient fish export with an injury rate as little as 3 percent, although study results have varied.

The video features manual insertion of the fish. In the wild, Whooshh counts on fish making semi-voluntary entries into the tubing. Once they swim into an enclosure, they’re curious enough about the tube to go inside.

If all goes well, the system could help salmon be reintroduced to the Upper Columbia River in Washington, where the population has been depleted by dams. Testing of the device there is awaiting approval from the U.S. Army Corps of Engineers.

[h/t Popular Mechanics]

Virginia Zoo Is Auctioning Off the Chance to Name Its New Red Panda Triplets

bbossom/iStock via Getty Images
bbossom/iStock via Getty Images

The red panda population at the Virginia Zoo grew significantly earlier this summer, The Virginian-Pilot reports. On June 18, mother Masu and father Timur welcomed a brood of triplets into the world, bringing their total number of offspring up to five. The three red panda babies are currently without names, but the zoo is giving a few lucky bidders the chance to change that.

Red pandas are endangered, with fewer than 10,000 of them living in their natural habitat in the Eastern Himalayas. Red panda breeding programs, like the one at the Virginia Zoo in Norfolk, are a way for conservationists to rebuild the species's dwindling numbers.

In 2017, Masu relocated to Virginia from the Denver Zoo as a juvenile. Zookeepers paired her with a male red panda there named Timur, and in June 2018, she delivered twin cubs named Adam and Freddie. Red pandas typically breed in the spring and summer months and usually have just two babies at a time. But when Masu gave birth again this past June, she had three tiny cubs.

The three new red panda babies each weighed about 5 ounces when they were born and weigh roughly a pound today. Masu has been moved to a private, climate-controlled den to care for her young and will be returned to her original exhibit with her cubs sometime this fall.

By the time they make their debut, the youngest red pandas at the Virginia Zoo will have names, chosen not by the zoo, but by members of the public. Starting yesterday, August 19, and ending August 30, the zoo is holding an online auction for the naming rights of each of the three red panda cubs. As of press time, the honor of naming the two boy red pandas has already been sold for $2500 each, and the current bid for the girl stands at $1000. All the money that's raised will be donated to the Zoo’s conservation partner, the Red Panda Network.

Perhaps due to the results of previous public naming contests, the Zoo did lay out a few stipulations for the winning bidders. It won't accept any repeat names of red pandas that have lived there in the past. Additionally, "any racial, religious or ethnic slurs, explicit language, obscene content, reference to alcohol, drugs or other illicit substances or otherwise unlawful, inappropriate, objectionable, or offensive content" will be rejected. All name submissions from the winners are due to the zoo by September 9.

[h/t The Virginian-Pilot]

SECTIONS

arrow
LIVE SMARTER