I love jellies, and it breaks my heart that so many people assume the world is now a beautiful place for jellies to live, because in many cases, it’s not. Even though many news organizations claim that jellies are increasing globally, there isn’t much science to back this up . So what’s with the disconnect? One big reason: If jellies are around, people remember. If jellies disappear, who cares? When jellies arrive it often makes the news, but when jellies vanish there’s less discussion.
This makes me really sad. Who will notice that beautiful jelly species slowly decreasing in number? Well, apparently Swedes will. Thank goodness. According to Alaska Dispatch, this beautiful animal, once common in the North Sea, has “has largely vanished from off Sweden’s west coast”
And this isn’t good news for beach-goers either. Jellies are an important part of the environment:
According to researcher Lene Friis Möller, the disappearance of the sea jellies can lead to much heavier algae blooms, a reduction in the number of fish, and cloudier water.
What’s causing the decline? Lene Friis Möller tells Alaska Dispatch that the invasive sea walnut (Mnemiopsis sp.) may play a role, but things aren’t so clear. What is clear is that not all jelly species are on the rise, and all this hype may mask the slow decline of many amazing jellies.
 Beyond the jellyfish joyride and global oscillations: advancing jellyfish research