Jellyfish and Climate Change
Although our story is set in a tank, in a restaurant in Las Vegas, and our heroes Jake and Josie are searching for love there, in the real world—outside of animation—jellyfish have been adversely affected by climate change, like many other animals all over the globe.
Curiously, instead of dying off, as many other species have, the worldwide jellyfish population has exploded as ocean temperatures have risen.
Although we love jellies, too many of them can cause an imbalance in our oceans.
In 1999, jellyfish caused an electricity blackout in Manila, Philippines.
In 2006, jellyfish brought a nuclear-powered U.S. aircraft carrier to a standstill.
In 2007, in Northern Ireland, salmon farmers described “billions” of jellyfish filling a space of about 20 square meters. The entire inventory of the Northern Ireland salmon farm died; the salmon died due to stress, suffocating from battling boats trying to get through, and being stung to death by jellyfish.
In 2011, in Scotland, reactors at a nuclear power plant were shut down, after an invasion of jellyfish blocked the cooling filters.
In 2013, in Sweden, jellyfish invaded and forced the closure of a nuclear power plant.
These types of events have increased in scale and frequency. The trend isn’t healthy for our planet, and this surge in the jellyfish population is telling us something about the imbalance in our world oceans.
The overabundance of jellyfish is caused by climate change. Here are some reasons why:
1. Heated ocean temperatures worldwide.
Over approximately the last 100 years, the average temperature of the world’s oceans has risen by 0.9 degrees Celsius. As the oceans get hotter, certain marine creatures are able to travel, live, and spread into areas that usually would be too cold for them.
2. Oxygen levels in the sea have dropped.
Due to rising temperatures and increased pollution, oxygen levels in the ocean have fallen by about 2% in the last 50 years. Jellyfish can thrive in low-oxygen-level waters (whereas other animals suffer in that kind of environment).
3. Depletion of jellyfish predators.
Overfishing of our oceans has caused the depletion of global stocks of tuna and swordfish, which are two of the jellyfish’s predators. Overfishing has also depleted many of their competitors for food, such as anchovies. With more food available and far fewer predators, jellyfish populations continue to grow.
Climate change is a result of human actions.
Beside climate change factors, from an evolutionary perspective, jellyfish have been through a lot. They’ve been around for at least 500 million years—which means they’ve had 500 million years to learn how to survive! They’ve endured through mass extinctions, and some scientists say that they are so efficient with food that they don’t need to eat much. If necessary, they can tolerate months of starvation. Their evolutionary knowledge of how to survive gives them a leg (or a tentacle!) up on other species that might otherwise perish faster in today’s oceans.
What You Can Do
If you’d like to help our oceans, and help jellyfish and other sea life to live more healthfully, here are some organizations doing wonderful work to help save our oceans:
Articles
Jellyfish are taking over the world — and climate change could be to blame (World Economic Forum)
Climate Change is causing destructive explosions of jellyfish (Fast Company)
What do jellyfish teach us about climate change? (The Guardian)
Books
Spineless: The Science of Jellyfish and the Art of Growing a Backbone
by Juli Berwald
Jellyfish Fun Facts
There are more than 2,000 different kinds of jellyfish.
They have no blood, brain, eyes, or spine.
They’ve been around for 500 million years—and some say even longer than that!
Jellyfish don’t touch when they procreate.
