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4 Reasons Why You Shouldn’t Feed the Birds (Or Any Animals)

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People love to feed birds. And squirrels, chipmunks, deer—even bears and sharks. We do it for our own pleasure and, sometimes, under the misguided impression we are helping hungry animals. But step away from the stale bread—here are four reasons why feeding wildlife is almost always a bad idea, both for the animals and for us.

1. FEEDING CAN LEAD TO INJURED ANIMALS AND PEOPLE.

Researchers at Murdoch University in Western Australia and University of Aberdeen in Scotland analyzed nearly two decades worth of data from Chicago’s Brookfield Zoo Sarasota Dolphin Research Program and Mote Marine Laboratory’s Stranding Investigations Program and found an increase in the number of dolphins being fed by humans—along with an increase in dolphins injured or killed by boat strikes, entanglement in fishing gear, and ingestion of hooks and lines.

At Stingray City, a shallow lagoon off Grand Cayman where large numbers of stingrays gather around boats of tourists that feed them, handling by those tourists had caused skin abrasions on the rays.

Fed animals begin to equate humans with food, and can exhibit increased aggressiveness toward people, which has resulted in human injuries and even death. People have been bitten while feeding wild animals, some of which carry infectious diseases such as rabies, bubonic plague, or Hantavirus.

2. FEEDING ALTERS THE NATURAL BEHAVIOR OF ANIMALS.

Feeding wildlife can change the animals’ activity levels and metabolic rates, reduce the size of their home range, and increase both intra- and inter-species aggression.

Sharks, for example, don’t naturally share territory, and when they group around boats to feed, it can cause stress and shark-on-shark conflict. “Sharks are solitary predators not normally found in groups,” George Burgess, director of the Florida Program for Shark Research, told mental_floss. “With feeding, they associate humans in the water—and even the sound of a motor boat—with food, and come from long distances away. Most don’t go far away once the boat leaves, but hang out in the area knowing the boat comes every day, so the reality then is sharks in unusually high densities.” Unnaturally high numbers of predators in one place equals equally unnaturally high levels of predation, which affects the ecology of the entire area.

Whitetip reef sharks that are fed in order to attract them for tourists showed elevated activity levels and increased metabolic rates during times they normally would rest. Metabolism influences most of an animal’s biological and ecological processes, so this represents clear evidence of feeding affecting the sharks’ critical biological functions.

Researchers found that the rays at Stingray City have distinctly different patterns of activity than their wild counterparts. Wild stingrays forage at night across large distances and rarely encounter each other. The fed rays form schools, feed together, and mate year-round rather than during a specific season. They also show signs of unusual aggression, such as biting each other. Scientists don’t yet know whether these behavior changes could be harmful in the long run.

In Slovenia, where bears are fed corn year-round, scientists found that the animals shortened the number of days of hibernation by as much as 56 percent. Bears regularly visited feeding sites throughout the winter, increasing their likelihood of interactions with other species as well as humans.

3. FEEDING CAN MAKE ANIMALS SICK.

On some islands in the Bahamas and throughout the Caribbean, tourist operators take people to feed grapes, ground beef, and other foods to one of the world's most endangered lizards, northern Bahamian rock iguanas. Researchers reported different levels of calcium, cholesterol, and various minerals in fed versus unfed populations of the iguanas, as well as diarrhea, higher levels of glucose, and a staggering 100 percent endoparasitic infection rate in the tourist-fed animals. One of the study’s authors, Charles Knapp of the Chicago John G. Shedd Aquarium, recommends an education campaign to discourage iguana feeding and, at a minimum, using food specially formulated for the iguanas.

In another devastating example, people frequently feed bread, popcorn, and fast food to white ibis in parks in Georgia. As a result, the birds are more sedentary than normal, and they come into contact with ducks, gulls, and city birds they normally wouldn’t encounter. Increased inter-species contact, combined with higher levels of stress hormones and weaker immune systems, could increase the spread of pathogens such as salmonella among them. A previous study found ibises infected with strains of salmonella that also make people sick—because of their range, the birds could move these pathogens over large distances.

4. FEEDING CAN EVEN LEAD TO ANIMALS BEING KILLED.

All U.S. national parks prohibit the feeding of wildlife. But in some parks, bears have learned to forage for unattended human food. Rangers relocate these bears away from human food sources, but many eventually return and continue seeking human food—eventually, such problem bears must be euthanized. Being fed from cars can cause bears and other animals to congregate near roads where they may be killed by vehicles. Hanging around roads and parking lots can also make animals such as squirrels, birds, and deer easier for predators to catch.

Tourists on Fraser Island, Australia have come to expect interaction with dingoes, including feeding the wild dogs. As numbers of tourists increased, so have reports of dingo attacks, and after a human fatality in April 2001, the government ordered a cull of the dingoes.

Fed sharks lose their natural fear of humans and become bolder, coming closer than they normally would once they associate humans with food. When bites result, it contributes to the negative image sharks can have, Burgess says. “The sharks get the blame, not the humans in the water with bait and fish. We have a designation in the shark attack file, 'Provoked Attack,' meaning ones in which humans initiated the attack by doing something to provoke the animal. What is more provocative than dangling fish in front of a shark’s nose? Of course, the word provoked doesn’t appear in the headline. Whatever advantage is gained in conservation by letting people see what beautiful animals sharks are gets cancelled out by the headlines of someone getting bit.” In response to shark bites, officials sometimes kill sharks in the area where the encounter occurred even though, Burgess says, the chances of killing the specific shark involved are slim to none.

He notes that feeding can result in shark deaths another way: “There have been examples where fishermen came to areas where sharks were attracted by a feeding operation and fished them out."

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Good News, Dog Parents: You Can Teach Puppies as Well as Their Canine Moms Can
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If you’ve ever adopted a puppy, you probably know how frustrating it can be to teach your new family member the basic tenets of common decency, like not to pee on the carpet or tear up a whole roll of toilet paper.

In other areas, though, pups are rather impressive learners, capable of mimicking some human behaviors. In fact, for some tasks, they learn just as effectively from watching people as they do from watching other dogs, including their own mothers, a new study in Nature revealed.

Researchers from Hungary and the UK took 48 young puppies of various breeds and studied the conditions under which they can be taught to open a puzzle box containing food. The experiment revealed that the puppies were able to learn how to open the box regardless of whether the task was first demonstrated by a person, their mother, or an unfamiliar dog. In other words, not only are puppies capable of social learning, but they're able to learn tasks from humans they don't know—in this case, the experimenter.

However, researchers were surprised to learn that the puppies were more likely to learn how to open the box by watching an unfamiliar dog than by watching their own mothers. That may be because puppies spend more time looking at—and thus, learning from—an unfamiliar dog that intrigues them. This differs from other species such as kittens, which “learn to press a lever for food more rapidly from their mother than from an unfamiliar adult,” the study notes.

In addition, the puppies were able to perform the task again after a one-hour break, indicating that they had retained some memory of the learning experience.

The ability of dogs to learn from humans has been recorded in previous research. A 2015 study revealed that dogs learn better by demonstration (or the “do as I do” method) than training techniques that involve a system of punishments and rewards. The "do as I do" approach probably isn't the most practical method of teaching your pup to do its business outside, but if you already have an adult dog at home, your new puppy can follow the older dog's lead and learn by example.

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Michael Hutchinson
Spiders Can Fly Through the Air Using the Earth's Electric Field
A spider exhibiting ballooning behavior.
A spider exhibiting ballooning behavior.
Michael Hutchinson

Every so often, otherwise Earth-bound spiders take to the air. Ballooning spiders can travel hundreds of miles through the air (and, horrifyingly, rain down on unsuspecting towns). The common explanation for this phenomenon is that the spiders surf the wind on strands of silk, but there may be other forces at work, according to a new study spotted by The Atlantic.

In the research, published in Current Biology, University of Bristol scientists argue that Earth's atmospheric electricity allows spiders to become airborne even on windless days. To test their hypothesis, the researchers exposed spiders in the lab to electric fields similar to those naturally found in the atmosphere.

When the electric field was turned on, the spiders began to exhibit behavior associated with ballooning—they "tiptoed" on the ends of their legs, raised their abdomens, and released silk. Spiders only exhibit this behavior when ballooning. And when they did become airborne, the spiders’ altitude could be controlled by turning the electric field on and off. When the electric field was on, they rose through the air, but when it was off, they drifted downward.

This provides a potential explanation for why spiders take to the skies on certain days but not others, and how they can fly in calm, windless weather— something scientists have puzzled over since the early 19th century. (Even Darwin was flummoxed, calling it "inexplicable," The Atlantic notes.) However, the researchers note that these electric fields might not be totally necessary for ballooning—wind alone might work perfectly fine on some days, too. But understanding more about when and how spiders become airborne could help us predict when there will be large masses of arachnids flying through the skies (and hide).

[h/t The Atlantic]

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