How to Give a Fish an Ultrasound

December 10, 2015 Comments Off on How to Give a Fish an Ultrasound

Performing an ultrasound on a fish might not, at first, seem like such a grand undertaking.

But what if it’s a really big fish that lives at the bottom of a really deep tank? Now we’re talking excitement.


So it was with the largest lake sturgeon in our Isle Royale tanks. We call her Helga.

It took three divers with a large net to get her up to the surface.


It then took four dry staff members to get her in a holding tub.


Our staff went to this effort due to concerns that Helga might be carrying eggs. At 33 years old, Helga has reached the age of sexual maturity.  Unlaid eggs can cause serious health problems for sturgeon. It’s a potential issue for aquarium fish which are in static environments because they are without the natural environmental changes (sunlight, water depth and temperature variations) that can trigger a spawning mode.


Once Helga was sedated and calm, Dr. Ralph began the ultrasound. Good news, no eggs! Had the sturgeon been egg-bound the next step would have been to schedule surgery to remove them.


Immediately after the ultrasound, Helga was measured and weighed. She’s 5 feet long and weighs 62 lbs.! Her weight will now be monitored regularly. Extreme weight gain in the future could be an indication that she is carrying eggs.


It all took just minutes to accomplish all this.  Helga was then gently and slowly returned to the bottom of our Isle Royale tank with the help of our staff divers Jorie and Nathan.


Helga rested for a good part of the morning and then was back to her old self.