Sea Spider - Distribution and Ecology

Distribution and Ecology

These small animals live in many different parts of the world, from Australia, New Zealand, and the Pacific coast of the United States, to the Mediterranean Sea and the Caribbean Sea, to the north and south poles. They are most common in shallow waters, but can be found as deep as 7,000 metres (23,000 ft), and live in both marine and estuarine habitats. Pycnogonids are well camouflaged beneath the rocks and among the algae that are found along shorelines.

Sea spiders either walk along the bottom with their stilt-like legs or swim just above it using an umbrella pulsing motion. Most are carnivorous and feed on cnidarians, sponges, polychaetes and bryozoans. Sea spiders are generally predators or scavengers. They will often insert their proboscis, a long appendage used for digestion and sucking food into its gut, into a sea anemone and suck out nourishment. The sea anemone, large in comparison to its predator, almost always survives this ordeal.