Coral Reefs Depend on Big Fishes’ Pee

None of us live, or pee, in a vacuum.* The substances that leave our body interact with our environments in a million little ways. Traces of prescription drugs in our waste travel through the waterways and affect the way shrimp live their lives. Someone else’s pee in a public pool can raise your risk of developing asthma. But not all excrement is harmful. Scientists say that fish pee is a necessary—and threatened—component of healthy marine ecosystems. The researchers published their findings in the journal Nature Communications. 

Lead author Jacob Allgeier studies ecology at the University of Washington’s School of Aquatic and Fishery Sciences. “Part of the reason coral reefs work,” he said in a press statement, “is because animals play a big role in moving nutrients around.” 

Researchers have been working since the 1980s to understand the relationship between fish and the health of their homes on the reef. Recent research has suggested a primary link: fish waste. Their pee is rich in phosphorus, and their gills give off ammonium—two chemicals corals need to stay healthy and strong. 

Allgeier and his colleagues wanted to test this hypothesis by looking at reefs where fish had been removed. They visited 43 different coral reefs in the Caribbean, ranging from pristine to over-fished. Allgeier caught and measured hundreds of live fish. He placed each one in a bag of water for a half-hour, then analyzed the water once the fish were gone.

Fish in a bag. Image credit: Jacob Allgeier

He found that large, carnivorous fish peed out more phosphorus than smaller herbivores, and that bigger fish almost always gave off more ammonium, making them especially desirable to a community of coral. Unfortunately, these same fish are also quite desirable to fishers, who yank the big ones right out of the ecosystem equation. 

“Simply stated, fish biomass in coral reefs is being reduced by fishing pressure,” Allegeier says. “If biomass is shrinking, there are fewer fish to pee.” 

He and his colleagues say these findings should influence future thinking about fishery management. “Fish hold a large proportion, if not most of the nutrients in a coral reef in their tissue, and they’re also in charge of recycling them,” he said. “If you take the big fish out, you’re removing all of those nutrients from the ecosystem.”

*This is not a challenge. Do not pee in your Dyson.

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Courtesy of The National Aviary
Watch This Live Stream to See Two Rare Penguin Chicks Hatch From Their Eggs
Courtesy of The National Aviary
Courtesy of The National Aviary

Bringing an African penguin chick into the world is an involved process, with both penguin parents taking turns incubating the egg. Now, over a month since they were laid, two penguin eggs at the National Aviary in Pittsburgh, Pennsylvania are ready to hatch. As Gizmodo reports, the baby birds will make their grand debut live for the world to see on the zoo's website.

The live stream follows couple Sidney and Bette in their nest, waiting for their young to emerge. The first egg was laid November 7 and is expected to hatch between December 14 and 18. The second, laid November 11, should hatch between December 18 and 22.

"We are thrilled to give the public this inside view of the arrival of these rare chicks," National Aviary executive director Cheryl Tracy said in a statement. "This is an important opportunity to raise awareness of a critically endangered species that is in rapid decline in the wild, and to learn about the work that the National Aviary is doing to care for and propagate African penguins."

African penguins are endangered, with less than 25,000 pairs left in the wild today. The National Aviary, the only independent indoor nonprofit aviary in the U.S., works to conserve threatened populations and raise awareness of them with bird breeding programs and educational campaigns.

After Sidney and Bette's new chicks are born, they will care for them in the nest for their first three weeks of life. The two penguins are parenting pros at this point: The monogamous couple has already hatched and raised three sets of chicks together.

[h/t Gizmodo]

Bleat Along to Classic Holiday Tunes With This Goat Christmas Album

Feeling a little Grinchy this month? The Sweden branch of ActionAid, an international charity dedicated to fighting global poverty, wants to goat—errr ... goad—you into the Christmas spirit with their animal-focused holiday album: All I Want for Christmas is a Goat.

Fittingly, it features the shriek-filled vocal stylings of a group of festive farm animals bleating out classics like “Jingle Bells,” “Rudolph the Red-Nosed Reindeer,” and “O Come All Ye Faithful.” The recording may sound like a silly novelty release, but there's a serious cause behind it: It’s intended to remind listeners how the animals benefit impoverished communities. Goats can live in arid nations that are too dry for farming, and they provide their owners with milk and wool. In fact, the only thing they can't seem to do is, well, sing. 

You can purchase All I Want for Christmas is a Goat on iTunes and Spotify, or listen to a few songs from its eight-track selection below.


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