15.09.2026 – Columbus crabs

While the Christopher Columbus Festival is taking place on our neighboring island of Porto Santo, we came across the very crab he was the first to describe after discovering it in Sargassum seaweed. He considered the appearance of this crab a sure sign of land being nearby. Today, we know that the Columbus crab (Planes minutus) is a tiny pelagic crab that never goes ashore and reaches a size of only 1 to 1,7 cm. It inhabits a wide variety of substrates—ranging from all manner of floating debris in the open ocean to animals such as the loggerhead sea turtle.
We were able to examine the crabs’ tiny undersides and distinguish between males and females: males have a visible triangle on their abdomen, whereas on a female, we could identify the oval egg sac. The specimens we found were brownish, though the color can also lean towards yellow or red.

Sightings of the day