Gooseneck barnacles

 

Shellfish

Gooseneck barnacles are kind of scary to look at — their alien-like appearance conjures up images from the sci-fi realms of "Star Trek" or "Doctor Who." They're weird, but their oddity and scarcity make them a luxurious delicacy. Gooseneck barnacles, otherwise known as percebes, may look like their cousins that attach to docks, but taste much better.

According to Atlas Obscura, gooseneck barnacles got their name centuries ago when medieval naturalists stumbled upon these claw-like sea creatures and thought they were goose eggs. They witnessed the crustaceans fall into the water and believed baby geese emerged fully formed from the dislodged barnacles.  

According to CNN, this seafood is among the most expensive in the world and can go for as much as $125 a pound. Toronto Life reports that in Europe, a kilogram of gooseneck barnacles could yield $500. Their price is related to a limited supply and the risk a fisherman must face to obtain this delicacy. 

Gooseneck barnacles are strange to look at, but a luxury dish worth trying. Low in calories, clocking in at just 66 calories per 100 grams. 15.7 grams of protein per serving, in addition to 0.4 grams of fat and 0 grams of carbohydrates. Rich in iodine, selenium, and iron. The nutrition content may change based on how you prepare the barnacles, and this ingredient can fit many diets on its own.

Any aquatic invertebrate animal having a shell and belonging to the phylum Mollusca, the class Crustacea (phylum Arthropoda), or the phylum Echinodermata. The term is often used for the edible species of the groups, especially those that are fished or raised commercially.

Bivalve mollusks, including oysters, mussels, scallops, and clams, rank among the most commercially important shellfish throughout the world. Certain gastropod mollusks, such as abalone, whelk, and conch, are also marketed. The main crustacean forms caught and eaten are the shrimp and prawns of the genera Crangon and Palaemon off the coast of Europe and the genus Penaeus in the coastal waters from North Carolina to Mexico.

The American lobster, the Norway lobster (also called Dublin Bay prawn), and the South African rock lobster are highly valued, as are the king crab and the Dungeness crab and its related species. Among echinoderms, sea urchins and sea cucumber (trepang, or bêche-de-mer) are locally popular. There is considerable confusion over the nomenclature of shellfish, compounded by the restaurateur’s tendency to name his offerings based on size rather than species.

After being harvested, all shellfish are highly perishable. Many types are cooked live to protect the consumer against the effects of spoilage. Most shellfish benefit from brief and gentle cooking; with high heat they may disintegrate or turn rubbery, and the flavour becomes disagreeably strong. Conch and abalone, however, must be pounded to tenderize the tough meat. Shellfish are often served with rich or highly seasoned sauces.

Acorn barnacles live along rocky shores throughout the north Atlantic and north Pacific oceans. Once an acorn barnacle attaches as an adult, it surrounds itself with a strong shell that provides it protection from predation and allows it to trap some water during low tide. Acorn barnacles live in the intertidal zone (the area between the high tide and low tide levels) and therefore needs to be able to survive long periods outside of the water. The shell can be closed tightly in order to prevent it from drying out. After they attach and build their little houses, acorn barnacles filter feed small plankton and other particles from the water using their modified legs. 

The acorn barnacle mating system is very interesting. Adults are hermaphroditic – they are both male and female – but they cannot self-fertilize and must mate with other individuals to successfully reproduce. Like most crustaceans, this species reproduces via internal fertilization. For a species that includes individuals that cannot move, that can be a difficult process. 

Fortunately, individuals of this species have extremely long penises – the longest penises (relative to body size) of the animal world. While the adult body size is typically not larger than a half inch (1.25 cm), the penis can be three inches long (7.5 cm), six times the length of the body. Using this organ, individuals can pass and receive sperm to and from their neighbors. Individuals that are more than three inches away from any neighbor cannot reproduce. Even more interestingly, the penis dissolves at the end of the mating season and grows back each year. 

Acorn barnacles are not utilized or seriously threatened by people in any way. However, visitors to the rocky shore must be careful not to trample these animals during low tide.

Those aren't dragon claws—they're gooseneck barnacles! These filter feeders are found in the rocky tide pools of Olympic Coast National Marine Sanctuary. Their shells are made up of multiple white plates that help protect them from predators and from drying out.

Of the more than 1,400 species of barnacles found in the world’s waterways, the most common ones are called acorn barnacles. As anyone who’s ever maintained a vessel knows, removing barnacles requires some elbow grease (or a pressure washer). That's why some boaters call them by their slang name: "crusty foulers."

Barnacles like places with lots of activity, like underwater volcanos and intertidal zones, where they reside on sturdy objects like rocks, pilings, and buoys. Moving objects like boat and ship hulls and whales are particularly vulnerable to the pesky critters. Large barnacle colonies cause ships to drag and burn more fuel, leading to significant economic and environmental costs. The U.S. Navy estimates that heavy barnacle growth on ships increases weight and drag by as much as 60 percent, resulting in as much as a 40 percent increase in fuel consumption!

Barnacles feed through feather-like appendages called cirri. As the cirri rapidly extend and retract through the opening at the top of the barnacle, they comb the water for microscopic organisms. They quickly withdraw into their protective shells if they sense a potential threat. Barnacles secrete hard calcium plates that completely encase them. A white cone made up of six calcium plates forms a circle around the crustacean. Four more plates form a "door" that the barnacle can open or close, depending on the tide. When the tide goes out, the barnacle closes up shop to conserve moisture. As the tide comes in, a muscle opens the door so the feathery cirri can sift for food.

 1-Barnacles are crustaceans

Although they were once thought to be related to snails, it turns out that barnacles are actually related to crabs. If you look at the animal inside the hard plates, it is possible to recognize their crab-like body plan.

2- They eat with their legs

Because barnacles are sessile animals, they have no need for the walking legs that many of their crustacean relatives possess. Their legs have adapted over time to a different use. They utilize their modified legs, called cirri, to sweep tiny food particles from the water column and pass them to their mouth parts inside their protective plates.

3- They can be parasites

The form of barnacle most commonly encountered by land-lubbing humans is the gray, volcano-shaped, stony type that can be found attached to piers, buoys and boat hulls around the world, but this is only one form that barnacles can take. They have a wide range of body plans, but one of the most bizarre is the rhizocephalan barnacle, which is an internal parasite in other crustaceans. They infiltrate and spread within the body of their host and even alter its behavior and appearance. Infected crabs can be detected by the external reproductive structure of the rhizocephalan that grows where the crab’s own eggs would be. The crab cleans and cares for this growth as if it were its own.

4- Those round marks on manatee backs are barnacle scars

There is a specific type of barnacle that attaches itself to manatees. When manatees enter the relative warmth of the springs during the winter months, the barnacles can’t survive in the freshwater and die. Eventually they fall off, leaving behind a round-ish scar on the manatee’s back.

5- They have the longest penis relative to body size of any animal

If you are a sessile animal (or a plant for that matter) how do you go about the business of reproduction? The favored technique is to let the water, wind, or other living creature do the business of scattering and mingling your gametes. If you are a barnacle you might take a different approach. Opting for internal fertilization, the exceptionally long penis of some barnacle species increases the odds that there will be another barnacle within reach to receive the sperm. The larvae are then released into the water column to settle as they will.

Barnacles are a highly specialized group of crustaceans. They have developed a sessile lifestyle as adults, attaching themselves to various substrates such as rocks, ships, whales or to sea turtles. Most commonly found barnacles on sea turtles belong to the genus Chelonibia, named after their host (Chelonia = turtle).

Most barnacles do not hurt sea turtles as they are only attached to the shell or skin on the outside. Others though burrow into the skin of the host and might cause discomfort and provide an open target area for following infections.

Excessive barnacle cover can be a sign of general bad health of a turtle. Usually sea turtles are debilitated first, and then become covered in an extensive amount of other organisms, such as barnacles and algae.