How Invasive Crayfish Help More Mosquitoes Thrive

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iStock

When invasive species somehow find their way into an environment where they don’t belong, they can disrupt everything from the food web to public health.

Recently, researchers at UCLA and other California institutions discovered an unwelcome squatter that might directly affect the spread of mosquito-borne disease. It’s the red swamp crayfish, a tasty delicacy often found in gumbo that may also be allowing mosquito populations to thrive.

Native to the southeastern U.S., the crayfish are now found in California. While investigating their damaging ecological presence, scientists made a chilling observation: In streams where crayfish concentrations were high, there was a noticeable spike in the number of mosquito larvae. They found something else, too—a sharp decline in the larvae-eating dragonfly nymphs that they would expect to see in the area.

In the paper, published in Conservation Biology, lead author Gary Bucciarelli observed 13 streams in the Santa Monica Mountains. Eight had crayfish populations and were high in mosquito larvae but low on dragonfly nymphs. Five crayfish-free streams had more nymphs and fewer larvae.

In a lab experiment putting the crayfish, mosquitoes, and dragonflies in proximity, Bucciarelli watched as the dragonfly nymphs—normally happy to prey on mosquito larvae—kept their distance in the presence of crayfish, apparently spooked by the crustaceans. In the wild, high concentrations of crayfish appear to be interrupting the dragonflies' hunting habits, allowing more mosquitoes to roam unchecked.

That’s not great news for humans. Mosquitoes are notorious for spreading viral diseases like West Nile, Zika, and malaria. In Los Angeles, where the mosquito population could conceivably get a boost, 15 of the 16 mosquito species can harbor pathogens that pose a threat to public health.

No one is quite sure how crayfish spread to the area—it’s possible fishermen used them as bait decades ago—but it's likely their presence will continue interfering with native species. In 2015, a nonprofit backed by the California Department of Fish and Wildlife started removing crayfish from the Santa Monica streams using traps set by volunteers. The captured crayfish were sent to Malibu to become snack fodder for opossums and raccoons. But it’s a sizable task. Roughly 600 crayfish might be caught in a given day out of the millions thought to inhabit the waters.

Conservationists might soon pursue more aggressive means to combat the crayfish's damaging ecological footprint. In addition to scaring dragonflies into inaction, they can threaten the integrity of underwater dams by burrowing and consume plants that help purify the water.

h/t National Geographic]

A Free Cup Share Program Is Coming to Coffee Shops in Boulder, Colorado

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iStock.com/fotostorm

Paper coffee cups are wasteful, taking decades to break down in a landfill after they're used for just a small part of someone's morning. But they're also irresistibly convenient to many. A new startup called Vessel Works is aiming to tackle the waste problem at coffee shops by applying the convenience of disposable to-go cups to reusable mugs, Fast Company reports.

The program, which is launching in four Boulder, Colorado cafes, takes the pressure off of customers to provide their own reusable cups. Instead, they can download an app and use it to check out an insulated, stainless steel mug free of charge. Throughout the day, the app updates them on ways their choice has made a difference, including how much waste they've prevented, how much water they've conserved, and how much they've reduced their carbon footprint. When they're done with the drink, users have five days to return their mug to a Vessel kiosk; from there it will be cleaned in one of the startup's facilities and returned to a cafe where the cycle will start all over again.

Vessel isn't the first company to attempt to bring reusable cups into the sharing economy. In 2016, coffee shops in Hamburg, Germany adopted a program where customers could acquire a mug for a small deposit and return it to a participating cafe to get their money back. Vessel Works's program differs in that users are never asked to pay unless they fail to return their cups on time (in that case, they'll be charged a fee).

Vessel is currently working with Boxcar Coffee Roasters and Trident Booksellers and Cafe in Boulder, and is coming soon to Seeds Library Cafe at the Boulder Public Library and the Pekoe Sip House at the University of Colorado. The startup hopes to eventually expand to more cafes and install dropoff kiosks at more convenient locations like transit stops.

[h/t Fast Company]

This Live Stream Lets You Eavesdrop on Endangered Killer Whales' Conversations

iStock.com/Serega
iStock.com/Serega

Southern resident killer whales, which are usually found off the coasts of Washington, Oregon, and British Columbia, are an endangered species. If you're lucky, though, you might be able to hear a pod of the killer whales chattering away from the comfort of your own home. A website spotted by The Kansas City Star lets you live stream the calls of killer whales from your phone or laptop. Dubbed Orcasound, it uses hydrophones (underwater microphones) to pick up oceanic sounds from two areas off the coast of Washington.

On the website, listeners can choose between the two locations. One is the Orcasound Lab in Haro Strait, which is situated off the coast of Washington's San Juan Islands—the "summertime habitat" of this specific ecotype of whale, according to the website. The other location is Bush Point at the entrance to Puget Sound, where the whales pass through about once a month in search of salmon. However, that hydrophone is currently being repaired.

So what do orcas sound like? They're loud, and they do a whole lot of whistling, whining, and clicking. You can hear a snippet of what that sounds like in a four-minute podcast uploaded to the Orcasound site.

There’s no guarantee you’ll hear an orca, though. "Mostly you'll hear ships," the website notes, but there's also a chance you'll hear humpbacks in the fall and male harbor seals in the summer.

The live stream isn't just for educational purposes. It also serves as a citizen science project to help researchers continue their studies of southern resident killer whales, which are in danger of starvation as Chinook salmon, their main food source, die off.

The makers of Orcasound are urging listeners to email ihearsomething@orcasound.net anytime they hear killer whales or "other interesting sounds." They can also log their observations in a shared Google spreadsheet. Eventually, developers of the site hope to roll out a button that listeners can click when they hear a whale, to make the process easier for people to get involved.

[h/t The Kansas City Star]

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