Training Tales: Jeremiah the Roughtail Ray

Whether in the ocean or in the National Aquarium, there is natural competition among animals for resources, including food. As a result, the different practices our experts use to feed Aquarium residents are focused on making sure that no animal gets outcompeted by another. But despite our staff's best efforts, the resident roughtail ray of Shark Alley, nicknamed Jeremiah, wasn't always getting the food intended for him during mealtime. There were two reasons for this: his anatomy as a ray, and his fellow residents of Shark Alley.

Rays' mouths are located on the underside of their bodies, so their natural behavior is to feed on the bottom of their habitat; in Jeremiah's case, this means skimming the floor of Shark Alley. During feeding time, some of the pushier residents of the exhibit—we're looking at you, nurse sharks—would sometimes snatch up Jeremiah's food before it made its way to the bottom of the habitat, where he spends most of his time.

To allow Jeremiah to bulk up and get ahead of the curve, he would spend a couple weeks in the backup pool area of Shark Alley every year, where he'd have the opportunity to focus on eating without all the competition from his fellow exhibit residents. Never satisfied to settle for the status quo, our expert aquarists started to think of alternative options that would allow Jeremiah to be more consistently fed in his habitat.

As a result, Jeremiah was moved to the backup area of Shark Alley for a long-term stay while our team target trained him. Their goal was to have him swim up the wall of his exhibit to be individually fed near the surface.

Aquarist Lindsey Fitzpatrick took the lead on target training Jeremiah; during the months-long process, they had a training session nearly every day. Here's how it worked: When it was feeding time, Lindsey would place a target in the water. Once Jeremiah approached the target, he was given fish—either herring or mackerel—so that he started to associate the target with food. Placing the target in the water is a bit like ringing a dinner bell; it signifies to Jeremiah that it's time to eat. This process of encouraging a specific behavior through the use of a reward is called positive reinforcement.

"Target training is very much a conversation. You're trying to converse with an animal that doesn't speak. You're trying to get them to do something specific and using positive reinforcement to say, 'Yes, that's what I'm trying to say to you.'" — Assistant Curator of Blue Wonders Jennie Janssen

At the beginning of Jeremiah's target training, he was consistently swimming up to the target in the water. This was a promising start, but our team soon realized that he would swim up to any object placed in the water and wasn't reacting to the target specifically. As a result, Lindsey had to make a few adjustments to the training process; for example, she started placing the target in the same spot every time Jeremiah was fed. Additionally, at the beginning of every training session, he was fed a few fish individually using tongs, and then fed the rest of the fish all at once. This method ensured that Lindsey could reward Jeremiah for coming to the target when he was most motivated to respond—in other words, when it was more likely he was hungry.

Target training an animal makes it easier to feed them and ensure that they're getting the amount of food they're supposed to, but there are a number of important welfare benefits to consider as well. For example, when Jeremiah needs to undergo exams in the future, the team could use his target training to lead him into the backup area, instead of corralling him into that space. When an animal is able to make choices in this way, they're more relaxed, which is always better for their welfare.

After several months in backup working on target training, Jeremiah recently returned to his exhibit and is putting his new skills to use during mealtime. Next time you're in Shark Alley, keep an eye out for the roughtail ray—if you spot his white target in the water, it may be feeding time!