Training with Urchins and Sea Stars!

What animals can’t be trained??

I had a lot of surprised friends several years ago when I did some clicker training and trick training with my goldfish Blaze. Many species are much more capable of learning than we give them credit for. A woman named Barbara Ray recently posted on one of the discussion groups I am on (the Click-L_ABAT list) about her experiences training urchins and sea stars. Using operant conditioning principles, which are the same principles that form the foundation for clicker training, even urchins and sea stars can be trained! I ask her if I could republish her post on my blog and she said that would be okay.

It amazes me, though, that so many people doubt that many species are not capable of learning. How else would the species survive in a changing environment? Barbara does a great job explaining how training principles can be applied to some species that are usually considered unlikely candidates for training.

——————————————-
Originally posted on click-L_ABAT on June 6, 2001.

I worked with seastars and urchins and various shellfish for many years, conditioning them to come and to station etc. These animals use various sensory organs to detect potential food and potential threats in their already very violent environments to which they are adapted (Reef habitats). So while we talk about them having no brains, theoretically one could say their body IS their brain, as the ganglia are spread out in a ring in the main body and branch out the arms etc.

What became hugely apparent and intriguing, from a behavioral evolution standpoint, is the different “urchinalities” the animals showed to the same sets of stimuli.

When transferred to a different holding tank, for example, there were urchins who became stressed and responded with the typical spines drooped as in detecting a threat (and possibly ‘change in tide” where they had to brace themselves and stop foraging activity if in the wild setting), there were urchins who took advantage of the ‘new’ environment to start exploring and identify potential new food source, and those that remained neutral to the same behavior or position prior to transfer.

When conditioning the animals to come, I used a light as a marker instead of a clicker, as they are very sensitive to light and dark cues and pay little attention to noise. Certain “tactile noise” (vibrational wavelengths) can elicit a defensive response, but I was not looking to scare them, I wanted to engage them. Most urchins and stars learned VERY quickly to come to station for a tidbit of shrimp (one of their favorite foods).

So millions of years of adaptation has afforded these animals to some very clever behavior to meet their needs, even though they lack a formal brain! (Same with plants of course, who also have their own behavioral evolutionary paths determined by the environments to which they must adapt or perish.)

Perhaps just the brain itself is not actually where the answers lie to explain the origin of some behavior or responses. Maybe there is other sensory input which is critically important but we focus so much on the brain, the other gets lost.

How else to explain how the brainless animals then also condition up in what appears to be so similar to animals with brains? Their physiology affords them chemical and photo receptors and tactile, EM receptors etc and some senses we probably have not completely identified but suspect exist.

To teach the ‘come when called’ response, for instance, that was done by shaping and luring. Using a touch on the animal’s spine or tentacle to get it’s ‘attention’ and luring with a piece of food. gradually raising criteria from moving the body to moving distance over time…so the animal eventually had to move from point A to B, such as coming from the bottom of the tank to a station at the side or top, to earn the shrimp reinforcement.

Fading the lure quickly was no problem, as again, these animals are adapted to an environment that very violently shifts from high tide to low twice a day, so their response to come for the reinforcement was quick with the cue, and no reinforcement present. Or I should say, none directly in their tanks! I have no doubt they can detect the food bits in the room from the ambient molecules that then enter the water through surface contact, drift and wave movement.

They had good ‘memory’ for the cue even after as long as 12 month ‘break’ without being in the training program.

The saltwater hermit crabs of course, with brains, were much more “fun,” as they could learn mugging behaviors and to demand attention (by tapping on the side of the tank with their foreclaws or one even learned to slug his shell on the tank wall as the sound was louder and more likely to get the human’s attention) when they wanted to be worked with/reinforced or saw their keepers and learned that by ‘asking’ for attention they could train the trainers to attend to them!

Its hard to resist a sweet-faced crab banging on the tank and looking at you directly with those big black pleading eyestalks, wondering why you are being so slow forthcoming with his shrimp! 🙂

Barbara and The Symphony of Hounds

If you liked this post, take a moment to share it!

, ,

Don't miss out on great information about animal training! Subscribe now to the Stale Cheerios newsletter and receive email updates when new posts are published.

Disclaimer: StaleCheerios posts occasionally contain affiliate links. Affiliate links are one way that StaleCheerios can continue providing top-quality content to you completely for free. Thank you for supporting our hard work! Learn more here.


  • Lottie Eriksson

    Thanks for sharing that! I'm on the Click-L ABAT list too but had missed this post. Fascinating.

  • Laurie H

    Very cool!

  • Radal16

    This is amazing and crazy mind-blowing.