What Are Jellyfish Ruining The Earth's Ecosystem?

I have seen the movie Finding Nemo a million times, or it seems like it anyway! I always loved the scene where Marlin and Dory play the game with the “jellies”. There were so many of them that they couldn’t even see the ocean anymore. Are jellyfish ruining the Earth’s ecosystem with over population? Some people, especially fisherman, are concerned that this is true, but we need to continue to investigate these mysterious creatures to figure out solutions to this potential problem. For most beachgoers jellyfish are just a nuisance. During certain times of the year jellyfish tend to pop up on the shore line and make our beach day and little less carefree. Moms are reminding their children to pay attention for the jellyfish so they won’t get stung! This is the least of the problems they are causing according to new information. In a recent Popular Science article, it states, “a ten mile wide and 42 foot thick swarm of baby mauve stingers decimated Northern Ireland’s farmed-salmon population. Overnight 120,000 fish were reduced to a floating mass of carcasses by billions of small jellies….” Wow, billions is a lot of jellyfish! This could definitely be cause for alarm and seems to build a case that the jellyfish could be changing eco systems.
The 120,000 salmon that were killed from stings and oxygen deprivation by the swarm of jellyfish was worth over 2 million dollars. China has specifically seen an enormous increase in jellyfish blooms. One fisherman stated that some fishermen have just stopped fishing and they get depressed when they pull the net up to find jellyfish. Some scientists believe that climate change is contributing to the increase because of warmer waters. They also believe that the oceans are becoming stressed and unhealthy and that this is a sign of that problem. So what can we do to help with this problem? Is there a