Volunteer divers at the National Aquarium perform a number of different tasks, both in the water and dry. On each of the four daily dives, the volunteers’ roles are divided up by the team captain depending on how many divers are there on a given day and what special needs the exhibits might have. There is always a “tender” who stays dry for at least two dives. (Since divers generally go straight to the Atlantic Coral Reef (ACR) exhibit after finishing the Wings in the Water—aka: the Ray Tray—feeding, the same person will remain topside for both.) This person is the safety watch during the dive, and is responsible for calling the divers in, whether for emergency or non-emergency reasons. The dive tender usually brings the animals’ food from the prep room to the exhibits, maintains a safe, dry(ish) platform, interacts with visitors, and gives the topside presentation at the Ray Tray while the divers are entering the tank. The position is rotated every week, again depending on the needs of the team members and the Aquarium.

The Ray Tray:

In the Ray Tray, the divers themselves have different feeding responsibilities. Usually one or two divers will handle the “general feed.” This means taking a bucket with assorted squid, smelt, shrimp, etc. into the water to feed the cownose rays, smaller Southern stingrays and if possible, the large tarpon.

The “target feeder” will usually concentrate on the larger Southern stingrays, the roughtail rays, the pelagic ray and the butterfly ray. These animals tend to be a little pickier, and need to be fed more deliberately so they don’t lose out to the more assertive cownose rays—for a visual, imagine trying to feed a litter of 20 puppies from a small bag of chow… now do that in scuba gear.

Choosier still are the bullnose rays. These two are shy, they tend to eat like models and, in my short experience, really only go for shrimp. A single diver handles this feeding. One technique that seems to work with the bullnose rays is to drop a few feet down into the well of the tank and hold the food close to the floor and wait for them to come by.

And then there’s Calypso. Calypso is the green sea turtle that lives in the Ray Tray and is a little overweight. So she’s on a vegetarian diet of cauliflower, Romaine lettuce, brussel sprouts and other assorted salads. Another diver stays with Calypso, feeding her (very carefully) by hand, and trying to keep her from wandering off and scavenging clams from the rays.

The ACR:

There is no less division of duties in the Atlantic Coral Reef exhibit. In the ACR, two divers usually split the role of feeding Oscar and Felix, the green moray eels. These guys are big, and have the jaw power to deliver what my team captain described to me as a “career-ending” bite. So generally, one diver will scout out the eel with a flashlight (the morays tend to hide out in crevices in the reef) and the other will follow with a bag of squid and fish and a long pole from which the food is offered. You can never tell with these guys; one day they’ll be so hungry they dive straight into the food bag itself, and another day you couldn’t pay them to eat. Sometimes they’re friendly and curious, and sometimes they just want to be left alone.

There is, of course, general feeding too. The larger reef fish are fed from buckets and the smaller fish eat a pureed mixture from squirt bottles. There are a few targeted fish as well. The porcupine fish eat from a separate bag of shrimp and shellfish. Another diver will be responsible for feeding the two stingrays that live in the ACR. The feeding technique is generally the same as in the Ray Tray, although these animals tend to stick to a smaller area in the tank.

Both of these tanks require additional maintenance from time to time. Divers are often asked to take suction cups, scrub brushes and rags to clean the reef or the glass. Scooping gravel away from the filters in the Ray Tray is a constant need.

Of course, one of the main responsibilities of the volunteer divers is to interact with and entertain the visitors on the other side of the glass. I’ve noticed that—at least with my dive crew—this is something that can be expected without asking.