We often scan the water’s edge in hopes of finding a new creature or just to marvel at the treasures the ocean has to offer. You never know what you will stumble upon whether you are shelling, snorkeling, or even just enjoying a day on the beach – that’s the beauty of ocean discovery! Last week we may have discovered what was perhaps, the coolest creature combination ever, by accident!
While exploring the mangroves during class, one of our curious students pointed out a familiar creature that we call "sea pork." This funny organism is a Tunicate, which is a filter-feeding, marine invertebrate that sometimes congregate in dense colonies. Tunicates acquired their name because they are tiny animals covered with a tough covering that resembles a tunic, or cape. Sea pork forms blob-like colonies that can range from light orange to dark blue. We often find sea pork washed up on the beach or in shallow seagrass beds, but this one was half-way buried beneath the muck.
We lifted the purple blob to have a closer look and quickly realized that the sea pork was not alone – a crab was clinging to the bottom! It turns out that we had discovered a decorator crab, a type of crustacean that attaches material from the ocean to it’s body for camouflage. This brilliant behavior is a classic and effective anti-predator strategy observed in many of species of crabs in the family Dromiidae. Certain species of decorator crabs even choose toxic algae or stinging anemones for additional protection – not a very tasty snack for hungry fish!
Under closer inspection, our decorator crab had also donned algae, a pea crab, and even had barnacles growing on his chelipeds (claws). This crab would have been otherwise invisible if we hadn’t picked up the sea pork. It is truly amazing to find things you least expect, and all it takes is a little bit of exploring.