A spotted eagle ray died Thursday at Point Defiance Zoo & Aquarium while being treated for skin parasites.
The creature arrived in Tacoma late last year and was going to be part of the Baja Bay exhibit in the new Pacific Seas Aquarium, which is scheduled to open this summer.
The spotted eagle ray had been living in an aquatic animal care center behind the scenes.
Officials said skin parasites are a common condition in the creatures, but are unsure why the spotted eagle ray had an adverse reaction to the treatment.
A necropsy is being performed.
"Every animal is precious, and we are saddenes by the loss of this eagle ray," said Karen Wolf, the zoo's head veterinarian.
Stacia Glenn: 253-597-8653