Moray Eel Checkup

We love our morays, I mean after all "that's amore."  Sorry for that.  Honestly though, our green morays are an awesome group of the Giant Ocean Tank population of fish. They look menacing, yet are docile animals. We offer them food every day (though some eels will not eat for weeks on end), and because of that we are quick to notice any odd behavior or physical issues. One day recently it was observed that our largest moray had a distended abdomen and a swollen vent, so we decided that a trip to the Aquarium Medical Center (just down the hall) was in order.  How do you catch and transport an eel anyway?


Once out of the tank and behind the scenes, she is wheeled down the hall to the medical center, where the vets take over.  First step--after closing all the doors just in case--is to add anesthesia to the water and wait for the eel to go into a sleepy state.

Having a look to see if she is asleep from the anesthesia yet

An inside view

Moving her to the exam table

After turning her 180 degrees to get closer...

...she began to expel eggs.  A LOT of eggs.

Like, almost 3 GALLONS of eggs!

Stitching her back up

And a quick blood draw for tests

Back in the eel bag she goes

Once back in the eel bag, she is put back in the barrel and wheeled back down the hallway for her return to the Giant Ocean Tank.  I'm pretty sure she feels much better :-)

Green morays, Gymnothorax funebris, typically range between 3 and 5 feet when seen in the wild, however this eel is close to 8 feet long and is the biggest of the five we have in the Giant Ocean Tank.  Green morays are nocturnal by nature, but it is not too uncommon to see one of ours swimming around the tank during the day. Come have a look and see if you can spy all five as you spiral up the Giant Ocean Tank ramp.


  1. Thanks for documenting this so well! Really good to see the process :)

  2. So was she egg bound?..

    1. Great question! Yes, she was egg bound.

  3. What's going to happen with the eggs? Will and how will they hatch?

    1. Another good question. The eggs were not fertile, so no baby moray eels here at the Aquarium.

  4. Fish with eggs normally absorb the eggs if they do not spawn, right? Does egg binding occur if a fish cannot absorb the eggs, and what would cause this to happen?

    I'm happy the big gal could be helped in time! :-)

  5. I thought fish had to be constantly submerged in water to survive. How were you able to keep her alive while you operated on her?

    1. Thanks for your interest in our animals! Yes, fish do need water in order to breathe. During a check-up, the eel is intubated with a hose that runs water over its gills. This video of another eel's check-up illustrates that process a bit better: http://news.neaq.org/2011/12/bob-eel-goes-to-vet.html


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