Pollicipes pollicipes

The goose neck barnacle is a fascinating marine crustacean. Its scientific name is Pollicipes pollicipes. People also call it the goose barnacle or the leaf barnacle. It is a member of the barnacle family. This species is highly valued as a food delicacy. It is especially popular in the Iberian Peninsula. This region includes parts of Spain and Portugal.

These creatures use a specific method to eat called filter feeding. They do not hunt like fish. Instead, they wait for food to come to them. They extend parts called cirri into the passing water. These cirri have a complex assortment of tiny hairs called setae. These hairs act like a net to catch nutrients. This allows them to eat many different things. Their diet includes diatoms, which are tiny algae. They also eat detritus, large crustaceans, copepods, shrimp, and molluscs.

The life cycle of a goose neck barnacle involves several distinct stages. It begins when the larvae are free-swimming in the ocean. These larvae must pass through seven different stages. The first six stages are known as nauplii. The seventh and final larval stage is called a cypris. This entire process takes at least one month to complete. After the cypris stage, the animal settles into a sessile form. Being sessile means the adult stays attached to one spot. They often grow in groups on rocks. They can also be found on driftwood or the hulls of shipwrecks.

Scientists have studied these barnacles for many years. Johann Friedrich Gmelin named this specific species in 1789. We now know that Pollicipes pollicipes has close relatives. One relative is Pollicipes polymerus. That species lives on the Pacific coast of North America. Another relative is Pollicipes elegans. That species is found on the coast of Chile. In 2010, a new species was described near the Cape Verde Islands. This new species is called Pollicipes caboverdensis.

The geographic range of Pollicipes pollicipes is quite large. Most populations live between 48°N and 28°N latitude. This area covers the coasts of France, Spain, Portugal, and Morocco. Their range extends south to Senegal. Some populations live as far north as Ireland. There are also outlying populations on the south coast of England. These English populations might be supported by larvae from core populations. The species is also present in the Mediterranean Sea, though it is rare there.

Humans have a very long history of interacting with these animals. Archaeological evidence suggests people have harvested them for over 10,000 years. Most harvesting is done manually by hand. In the Spanish market, they are known as percebe gallego. They are very expensive to buy. They can sell for as much as €90 per kilogram. Because they are so highly prized, the species is thought to be in decline. This means there may be fewer of them in the wild than before.

Understanding these barnacles helps us learn about ocean ecosystems. They connect the movement of water to the food web. By eating diatoms and small crustaceans, they process nutrients. They also provide a way for humans to study ancient coastal history. The way they settle on rocks and shipwrecks shows how they use the environment. Their survival depends on the health of the rocky shores in the Atlantic.