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Jellyfish are one of the oldest multi-organ animals found today; dating back at least 500 million years and some say even as many as 700 million years. There are even two or three that are considered immortal in that they can revert back to their polyp stage from the medusa stage. How amazing is that? But their increased prominence in our oceans is due to fishing down the food chain so that sea jellies have fewer predators and to the increased nutrients we are adding to our oceans via the rivers where the fertilizers and other chemical run off our land and into the water. Climate change is also affecting our sea jelly populations. Sea jellies are beautiful, graceful, elegant and mesmerizing and because of that, we have the opportunity to connect our visitors emotionally to our oceans and inspire the care and behaviour changes needed to help our oceans become healthy again. Over the past 500-plus million years, these beautifully tetra-radial symmetrical jellies have diversified with over 200 scyphozoans, and possibly up to a couple of thousand hydrozoan species. They can live for only a few hours to six months in the wild, though in our aquariums, they have lived much longer. They have even diversified how they reproduce from asexual budding and fission to sexual reproduction, which makes our job of maintaining sustainable populations within our facilities all the more challenging, and no wonder these amazing jellies have fascinated us for decades. |
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