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Steven G. Johnson via Wikimedia Commons // CC BY-SA 3.0
Steven G. Johnson via Wikimedia Commons // CC BY-SA 3.0

Invasive Comb Jellies Crowd the Adriatic Sea

Steven G. Johnson via Wikimedia Commons // CC BY-SA 3.0
Steven G. Johnson via Wikimedia Commons // CC BY-SA 3.0

In 1982, an unwelcome visitor arrived in the Black Sea. An oil tanker traveling from the American Atlantic dumped its ballast water into the sea, releasing a flood of warty comb jelly stowaways along with it. The alien invaders have since ravaged the area’s native fish populations, and now New Scientist reports that they’ve become a threat along the northern Adriatic coast.

Warty comb jellies (Mnemiopsis leidyi) have been seen in the Adriatic sea since 2005, but this summer marked the first time they’ve been present in such great numbers. Davor Lučić of the Institute for Marine and Coastal Research in Dubrovnik, Croatia told New Scientist that the clusters get as dense as 500 jellies per square meter in some spots. That estimate is based on fully-matured specimens—the number of juveniles is likely even higher.

The swarms have been documented along the Adriatic coast from Slovenia to Pesaro, Italy. Lagoons in northern Italy have been clogged with the creatures since July. The animals pose no direct threat to people, but their appetite has already proven disastrous to whatever ecosystem they invade.

A few of the warty comb jelly's meals of choice include fish eggs, fish larvae, and zooplankton. Zooplankton also happens to be the main food source for many commercial fish in the area. Less than a decade after the introduction of the comb jelly into the Black Sea, local anchovy and sardine fisheries were devastated. The seafood industry had lost billions by the mid-'90s.

Now, there’s threat of a repeat catastrophe in the Adriatic Sea. The mass emergence of the species coincides with anchovy spawning season, a crucial time for one of the sea’s most commercially significant fish. Some scientists are looking on the bright side: the Adriatic is more open and less polluted than the Black Sea, and its local fauna is more diverse. This makes the native populations better equipped to survive the invasion. Additionally, Mnemiopsis leidyi isn’t the sea’s only uninvited guest. Another comb jelly, Beroe ctenophore, has also invaded the waters, and scientists hope the aliens might contribute to one another’s demise.

Mnemiopsis likely entered the Adriatic through a ship’s ballast, the same Trojan horse it rode into the Black Sea. This problem isn’t limited to invasive jellies: A list of destructive species from ants to mussels have been introduced to new environments this way. A global treaty that aims to put an end to the issue will go into effect next year.

[h/t New Scientist]

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Courtesy of The National Aviary
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Animals
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]

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holidays
Bleat Along to Classic Holiday Tunes With This Goat Christmas Album
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iStock

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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