One of our main concerns at Ocean Conservancy is climate change and its impacts on our communities, resources and wildlife. Bleaching corals are among the first signs of climate change impacts we have seen have seen in our ocean. And though climate change has been a stressor on most ocean wildlife, there’s a particular group that has high adaptability and predicted success for the future, particularly in the face of climate change—sea jellies.

The future of our ocean depends on climate action. Urge your representative to support legislation to protect our ocean from the effects of climate change.

Sea jellies (or jellyfish) are a charismatic subphylum that is familiar to all. Fossil evidence dates sea jellies as far back as 500 million years ago—if not longer. They are soft-bodied creatures consisting of at least 95% water, possessing a simple structure and a noticeable lack of almost everything that distinguishes plant from animal—including blood, a heart and a brain.

Warming temperatures, increased salinity and increased acidity are causing the demise of many ocean creatures, but due to their lack of complex features, these are not a problem for sea jellies. In fact, warm temperatures and dead zones (areas of water with depleted oxygen) are places where sea jellies thrive; and because their natural predators, like sea turtles, fish and sharks, struggle in these changing environments, their numbers will only continue to grow. As the sea jelly population rises, here are a 10 photos of our favorite thriving jellies: