From Dutch daily De Volkskrant:
Since this summer, big numbers of Mnemiopsis leidyi are in the Wadden sea and Grevelingen lake.
In the Black Sea, the coming of this invasive species led to ecological disaster and the end of anchovy fishing.
This was discovered by Arnold Tulp (71), an amateur marine biologist and jellyfish expert from Nijega.
The animals may disappear after a cold winter; however, Tulp is anxious.
Especially as this species eats plankton eggs and larvae of molluscs and fish.
After its introduction in the Black Sea, about 25 years ago, the jellyfish, lacking natural enemies, became such a mass that they decimated other life forms.
In the Black Sea, the epidemic stopped at last.
Eventually, the Beroe ovale jellyfish turned up, a natural enemy of the Mnemiopsis comb jelly.
When the Mnemiopsis appeared in the Caspian Sea, the Beroe ovale was brought there on purpose.
The direct threat from the killer warty comb jellyfish to the Baltic cod population has been shown not to be so serious after all, according to new research from Denmark. Even though the invasive killer jelly feeds constantly, cod eggs seem not to be on the menu. In fact, if they accidentally swallow an egg, they even throw it up again: here.
Recent invasive species in Vermont, USA: here.
Coastal life of Singapore: here.
Warty comb jelly, Mnemiopsis ledyi, in the USA: here.