Humpback Whales in Canada Get Fish to Swim Right Into Their Mouths

iStock.com/psahota
iStock.com/psahota

Humpback whales are incredibly intelligent creatures, so it’s perhaps no surprise that they’re also savvy hunters. As Cosmos magazine reports, humpbacks off the northeastern coast of Vancouver Island have been seen tricking fish into swimming directly into their open mouths.

These cetaceans usually lunge toward their prey, and since they're about the size of a school bus, this is generally a pretty sound method. However, researchers spotted two humpback whales testing out a totally new tactic in 2011. Instead of chasing after fish, the crafty cetaceans were seen holding still while looking up towards the sky with half of their heads poking above the water. When they open their jaws, the dark recesses inside their mouths can easily be mistaken for a safe harbor, where fish might seek refuge from predatory seabirds. The cetaceans also use their pectoral fins to draw water towards them, and once the Pacific herring have been lured inside, they snap their powerful jaws shut. On average, they keep their mouths open for 18 to 90 seconds.

“The whale is providing a shadow or shelter,” Christie McMillan, executive director of the Marine Education and Research Society, tells The Vancouver Sun. “It’s like a Venus flytrap, a sit-and-wait idea. It’s not working so well for the herring, but it’s working for the whales.”

This trap-feeding technique was described for the first time by researchers from the society in a recent issue of Marine Mammal Science. Even more remarkably, the behavior seems to be spreading, which means the whales might be learning from each other. Only two humpbacks were spotted using the technique in 2011, but 16 were seen trap-feeding in 2015.

“Based on the rapid diffusion of the behavior and the characteristics of the prey consumed using this technique, trap-feeding appears to be an energetically efficient method of foraging on juvenile herring that is culturally transmitted between humpback whales," the researchers write in their paper.

The behavior hasn’t yet spread among humpbacks beyond British Columbia, as far as researchers can tell. However, Bryde’s whales in the Gulf of Thailand have exhibited similar feeding behaviors, according to The Vancouver Sun.

[h/t Cosmos]

No Venom, No Problem: This Spider Uses a Slingshot to Catch Prey

Courtesy of Sarah Han
Courtesy of Sarah Han

There are thousands of ways nature can kill, and spider species often come up with the most creative methods of execution. Hyptiotes cavatus, otherwise known as the triangle weaver spider, is one such example. Lacking venom, the spider manages to weaponize its silk, using it to hurl itself forward like a terrifying slingshot to trap its prey.

This unusual method was studied up close for a recent paper published in the Proceedings of the National Academy of Sciences by researchers at the University of Akron in Ohio. They say it's the only known instance of an animal using an external device—its web—for power amplification.

Hyptiotes cavatus's technique is simple. After constructing a web, the spider takes one of the main strands and breaks it in half, pulling it taut by moving backwards. Then, it anchors itself to a spot with more webbing in the rear. When the spider releases that webbing, it surges forward, propelled by the sudden release of stored energy. In the slingshot analogy, the webbing is the strap and the spider is the projectile.

This jerking motion causes the web to oscillate, tangling the spider's prey further in silk. The spider can repeat this until the web has completely immobilized its prey, a low-risk entrapment that doesn’t require the spider to get too close and risk injury from larger victims.

The triangle weaver spider doesn’t have venom, and it needs to be proactive in attacking and stifling prey. Once a potential meal lands in its web, it’s able to clear distances much more quickly using this slingshot technique than if it crawled over. In the lab, scientists clocked the spider’s acceleration at 2535 feet per second squared.

Spiders are notoriously nimble and devious. Cebrennus rechenbergi, or the flic-flac spider, can do cartwheels to spin out of danger; Myrmarachne resemble ants and even wiggle their front legs like ant antennae. It helps them avoid predators, but if they see a meal, they’ll drop the act and pounce. With H. cavatus, it now appears they’re learning to use tools, too.

[h/t Live Science]

Plano, Texas Is Home to a Dog-Friendly Movie Theater That Serves Bottomless Wine or Whiskey

K9 Cinemas
K9 Cinemas

For dog owners in Plano, Texas, movie night with Fido no longer just means cuddling on the couch and browsing Netflix. The recently opened K9 Cinemas invites moviegoers—both human and canine—to watch classic films on the big screen. And the best part for the human members of this couple? Your $15 ticket includes bottomless wine or whiskey (or soft drinks if you're under 21).

The theater operates as a pop-up (or perhaps pup-up?) in a private event space near Custer Road and 15th Street in Plano. Snacks—both the pet and people kind—are available for $2 apiece. Dogs are limited to two per person, and just 25 human seats are sold per showing to leave room for the furry guests.

Pet owners are asked follow a few rules in order to take advantage of what the theater has to offer. Dogs must be up-to-date on all their shots, and owners can submit veterinary records online or bring a hard copy to the theater to verify their pooch's health status. Once inside, owners are responsible for taking their dog out for potty breaks and cleaning up after any accidents that happen (thankfully the floors are concrete and easy to wipe down).

While many of the movies shown are canine-themed—a recent screening of A Dog's Journey included branded bandanas with every ticket purchase—they also hold special events, like a Game of Thrones finale watch party (no word on how the puppers in attendance responded to Jon Snow finally acknowledging what a good boy Ghost is).

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