Coast Tip: Gumboot Chiton

You know it’s true: spring is a sexy time of year. Reproduction is happening all around us in the Great Northwest, whether it be via the emergence of wildflowers on hilltop meadows, the release of allergy-inducing pollen in the valley, or, on the coast, aquatic spawning events. One such spawning event we deem worthy of an excursion to the local shoreline. Fans of tide pooling—pay special attention.

Gumboot chiton (Cryptochiton stelleri) are the largest chitons in the world, reaching just over a foot in length, while most others range from palm to fingernail-sized. Oval in shape, their tops are brick red and leathery, while their bottoms, or foot, are bright yellow. This foot acts something like a suction cup, keeping the gumboot attached to where they make their dwelling in the rocky intertidal. 

Unlike their smaller brethren chiton, gumboots are more easily dislodged. When knocked off the rocks by rough waves, they curl up into a football-like shape, perhaps a technique to protect themselves from getting thrashed around when the tide is high, or from drying out when the water recedes in a storm’s aftermath.  

Gumboots would rather not to move too far—in one experiment, adults only moved about 65 feet in 2 years. Considering they can live to be over 20, they may only cover a little over a tenth of a mile in their lifespan. But there’s no need to go far when a tide pool provides all the scrumptious algae these homebodies could ever desire.

Spawning season occurs March through May, and gumboots on the Oregon Coast have already been spotted getting down and dirty. During the spawn, the chitons are found in more dense numbers. They are broadcast spawners with females releasing strings of bajillions of little eggs, queuing males to emit clouds of milky white sperm into the shallow tide pools. 

On the Central Coast, the tide pools at Otter Rock are hard to beat when wanting to check out the gumboots. As a designated marine garden, no harvest is legal here (though gumboot chiton are edible), making for a more intact system to explore. In addition to restraining yourself from taking critters home with you, tide pool etiquette asks that you walk on bare rock as much as possible, touch gently, and never pry. After all, you wouldn’t want someone disrupting you while procreating, would you?

By Ari Blatt