Smoke is our 37-year-old Atlantic Harbor seal, which makes her one of the oldest seals in an aquarium. (Here's how we celebrated her birthday last year). She has had cataracts in both eyes for many years and is blind with the exception of seeing an occasional shadow. Some older seals, like other older animals and people, can develop cataracts. When an animal is blind, it is easy to assume that they cannot be trained. However, this is not the case. Smoke can be trained to do virtually anything a sighted seal can. However, there are some differences in HOW she is trained.
Smoke, being a seal, has sensitive whiskers. The technical term is called "vibrissae" because they are sensitive enough to pick up subtle changes in vibrations in her surroundings. This is great news for training. Using a hand target, I can guide Smoke's head and body into different positions. Here is a video of several behaviors all being asked for by very subtle changes in my hand position to her whiskers. Metaphorically speaking, communicating with touch could be compared to using braille vs. sign language.
Lana is another older seal with cataracts. Like Smoke, we utilize her whiskers as much as possible in the training process. Many of the seals have been trained to retrieve a seal toy from the water. Obviously, this can become a difficult task if you can't see. With Lana, I retrained her fetch behavior basing it on her sense of hearing and touch vs. sight. I attached a long, blue strap to Lana's retrieval toy. Initially, Lana hears the toy splash into the water and swims toward that general direction. Once she touches the strip with her whiskers she can follow it all the way to the toy and bring it back.
I have recently begun working with another interesting character. It's an African Lungfish that lives behind the scenes here at the New England Aquarium. The first thing I wanted to teach him was to target. In this case, I wanted to reinforce him for touching a particular bead. However, it became clear to me quickly that this fish does not have good eyesight.
I decided to take a similar route as I did with training Smoke and Lana; refusing to base the training on his sight, and instead using vibrations in the water to guide him. An African lungfish has several sensors on its face and a lateral line system down its body that, like whiskers on a seal, can detect subtle changes. This is a picture of the Lungfish targeting (at left) and a video of him responding to vibrations to be guided into a tube (below).
Last autumn, it was a wonderful experience when residents from the New England Homes for the Deaf came to visit. The residents, who happened to be blind and deaf, met Smoke. The interaction between both Smoke and the residents was completely based on touch. Smoke used her whiskers to touch their hands and the residents were able to feel her whiskers and face. Communication through touch alone seemed to be more than enough for each resident to crack a huge smile.
Working with these animals has taught me how significant touch is for communication. Adapting to different training techniques has helped broaden my experience and look at training situations from several angles. I am grateful to have the opportunity to work with these animals. They have taught me more than I could ever teach them.