Mountains of Jellyfish

In recent weeks there have been reports of large masses of jellyfish along the Gulf Coast.  I have actually heard people state “I would rather be in the water with 100 sharks than 100 jellyfish”.  Maybe that is true from some.  Honestly, it seems dealing with sharks could be easier.  Jellyfish are just there in a swarm.  The more you try to move them away, the more they come towards you – it is like trying to avoid the smoke from a campfire.

 

But jellyfish exist and people sometimes have to deal with them.  The thing they hate about them, of course, are their painful stings.  As Jimmy Buffett puts it – “They are simple protoplasm – clear as cellophane – they ride the winds of fortune – life without a brain”.  This is prreeettttyyyyy close.

Jellyfish are common on both shores of our barrier islands. This one has washed up on the beach.

The “cellophane” jelly material is called mesoglea and it is a protein-based material that is 90% water.  Lay a jellyfish on a deck and see what is left at the end of the day – not much.  The bell undulates rhythmically controlled not by a brain but by a series of nerves – what some scientists call a “nerve net”.  At the base of the bell is a single opening – the mouth.  There are no teeth and whatever they swallow enters a simple gut where digestive enzymes do their work.  But it is the only opening – so, waste material must exit through the same opening.  Yes… they go to the bathroom through their mouth.  Nice eh…

 

Then there are the tentacles – those lovely tentacles.  These are armed with small cells called nematocysts that harbor a small dart tipped with a drop of venom.  Each nematocyst as a small trigger which, when bumped, will fire the dart injecting the venom.  When you bump a tentacle, you are literally bumping hundreds of these nematocysts and receive hundreds of drops of venom.  Some species hurt, some do not.  Those that hurt are no fun.

 

So, why SO many at one time in one place?

 

Most jellyfish feed on small food.  Those food sources tend to multiple when the water is warm (and it is warm right now) and there are lots of nutrients in the water.  When we have heavy rain (and we have had heavy rains this year) the runoff introduces large amounts of nutrients to the system.  Warm nutrient rich water mean increase in jellyfish food, which in turn means increase in jellyfish.  With winds and tides working together (and we saw this with the recent front that passed through), the jellyfish are shoved into smaller locations.  In recent weeks that has been close to shore and the thick masses of jellyfish we have witnessed.

 

They do fly the purple flags when jellyfish are spotted.  It us unusual for them to be a problem on both the Sound and Gulf sides.  So, usually if they are bad on the Gulf side, you can move your beach day to the Sound and be fine.  And remember – this too shall end.  It won’t last forever.

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Posted: September 1, 2022


Category: Coasts & Marine, Natural Resources
Tags: Florida Panhandle, Florida Sea Grant, Jellyfish


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