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An otter eating a fat Inn Keeper worm in Elkhorn Slough

Nestled along the picturesque coastline of California’s Monterey Bay, Elkhorn Slough is a hidden gem of biodiversity. This estuary, characterized by its tranquil waters and thriving ecosystems, is home to a remarkable creature that plays a vital role in the local food chain—the Fat Inn Keeper Worm (Urechis caupo). These unusual marine worms serve as a crucial food source for various marine animals, including the playful and charismatic sea otters that inhabit the region. Join us on a virtual journey through the Elkhorn Slough and learn about these fascinating creatures and the otters that feast upon them from the ‘EL Cat’ Monterey Bay Eco Tours boat.

The Remarkable Fat Inn Keeper Worm

The Fat Inn Keeper Worm, also known as the “fat innkeeper,” is a unique and often misunderstood marine species that thrives in the soft, muddy sediments of Elkhorn Slough. These creatures belong to the phylum Echiura and are considered a type of spoonworm. They are characterized by their tubular bodies, which can reach lengths of up to 20 inches (50 cm) and have a distinct appearance resembling a burrowed innkeeper holding a feather duster.

One of the most intriguing features of the Fat Inn Keeper Worm is its unusual burrowing behavior. They construct U-shaped burrows in the mud, with the top end of their bodies protruding slightly above the sediment surface. This adaptation allows them to filter-feed efficiently, capturing tiny organic particles and detritus from the water column. As filter feeders, they play a crucial role in nutrient cycling and maintaining water quality in the estuarine ecosystem.

A Delightful Otter Feast

The presence of Fat Inn Keeper Worms in Elkhorn Slough has not gone unnoticed by the local wildlife, particularly the enchanting sea otters (Enhydra lutris). Sea otters are renowned for their charming antics and their critical role in maintaining the health of kelp forests and estuaries.

When otters venture out into Elkhorn Slough, they often encounter these plump marine worms as a delectable treat. Sea otters have an insatiable appetite for various invertebrates, and the Fat Inn Keeper Worms are no exception. Using their nimble paws, otters grasp the exposed portion of the worm and deftly strip away the sediment to reveal the protein-rich body inside. This behavior is not only a spectacle for fortunate onlookers but also serves as a testament to the otters’ resourcefulness and adaptability.

The ‘EL Cat’ Monterey Bay Eco Tours Experience

For those eager to witness this captivating spectacle firsthand, the ‘EL Cat’ Monterey Bay Eco Tours boat offers a unique opportunity to explore the wonders of Elkhorn Slough and observe otters feeding on Fat Inn Keeper Worms up close. The guided tours provide a safe and eco-friendly way to experience the delicate beauty of this estuarine ecosystem while learning about the interconnectedness of its inhabitants.

As you cruise along the calm waters of Elkhorn Slough, keep your eyes peeled for sea otters floating effortlessly on their backs, using their chests as dining tables for their underwater feast. Their dexterity and the sheer joy they exude while enjoying their wormy meal make for an unforgettable wildlife encounter.

Elkhorn Slough is a testament to the rich biodiversity and natural wonders that thrive along California’s central coast. The Fat Inn Keeper Worms, with their distinctive appearance and essential role in the estuarine ecosystem, are an integral part of this intricate web of life. Witnessing sea otters enjoying these peculiar creatures is not only a delightful spectacle but also a reminder of the delicate balance that exists in our coastal ecosystems.

The ‘EL Cat’ Monterey Bay Eco Tours boat offers a front-row seat to this remarkable natural spectacle. So, whether you’re a nature enthusiast, a wildlife lover, or simply seeking a unique adventure, a visit to Elkhorn Slough promises an unforgettable experience and a chance to witness nature’s beauty in action, one Fat Inn Keeper Worm at a time.

A sea otter stretches its meal, pulling on the soft tissues that make up a Fat Inn Keeper Worm