Beachcombing

Range/Geographical Distribution: North Carolina to Florida and the Gulf of Mexico.

Habitat: Shallow waters along the coast including beaches, bays, and estuaries.

Description: A large, heart-shaped shell that is yellow on the outside with red/brown marks and pink on the inside.

Size: Can reach five inches in width.

Food: Filter feeder; eats plankton and detritus.

Predators: Fish and birds.

Conservation Status: No legal status.

Interesting Facts: Uses its strong foot to bury in the sand where it will sit and filter out plankton and detritus from the water column.

On the Coast: Cockle shells often wash up on Georgia’s beaches but both sides are rarely still connected.

Range/Geographical Distribution: From New England to Brazil in the Atlantic and from California to Ecuador and the Sea of Japan and the South China Sea in the Pacific.

Habitat: Estuarine and ocean waters along the coast.

Description: A hemispherical peach/gray bell with a red/brown border.  Has 16 short oral arms at the base of the bell.

Size: Can reach ten inches in diameter and weigh 50 ounces.

Food: Zooplankton.

Breeding: The medusa realease gametes and fertilized eggs turn into planula.  The planktonic planula larvae attach to a substrate and metamorphosize into a scyphistoma. Scyphistomae eat and grow and then can reproduce asexually by budding or by strobiliation where ephyra are released.  The ephyra then grow into medusa, the sexual stage that is recognizably a sea jelly.

Predators: Crabs, fish, and leatherback sea turtles.

Conservation Status: No legal status but they are an important food source for endangered leatherback sea turtles.

Interesting Facts: Cannonball jellies form symbiotic relationships with at least ten species of fish as well as juvenile spider crabs.  The latin name of this jelly means “many-mouthed hunter.”  The cannonball’s lifespan is three to six months.

On the Coast: Cannonball jellies are the most common sea jelly along the Georgia coast.  Their stinging cells do not usually harm humans and they often wash up dead on the beach.  Jelly “balling”, fishing for sea jellies, occurs in Georgia and the jellies are sent to Asian markets for consumption.

Range/Geographical Distribution: Cape Cod to Florida and the Gulf of Mexico.

Habitat: Shallow waters including bays, beaches, and estuaries.

Description: A large, pear-shaped snail with a deep channel between the whorls.  Shells are gray to light tan and have darker brown/red banding.  The shell opens on the right side.

Size: Can reach eight inches in length.

Food: Bivalves including mussels, clams, and oysters.

Breeding: Channeled whelks lay egg cases attached to a string buried in the sand.  Each disc-like egg case can contain 30 eggs and each string will have many egg cases.  The eggs hatch inside the case and the tiny whelks are miniatures of the adults.  Some newly hatched whelks will be eaten by their siblings and then the remaining babies eat their way out of the capsule.

Predators: Sea turtles, and blue crabs.

Conservation Status: No legal status.  Has been introduced in California.

Interesting Facts: Native Americans used parts of these whelks for jewelry and money.

On the Coast: Channeled whelk shells can be found on Georgia’s beaches and many are occupied by hermit crabs.

Range/Geographical Distribution: Delaware to the Gulf of Mexico.

Habitat: The surf zone of sandy beaches with lots of wave action.

Description: A small, wedge-shaped clam with highly variable colors ranging from yellow to red to brown to purple to white.

Size: Can reach ¾ of an inch in length.

Food: Filter feeder; eats plankton and detritus.

Breeding: Male and female clams release sperm and eggs directly into the water for external fertilization. Fertilized eggs hatch into trochophore larva that then grow into veliger larva.  The veliger settles to the benthos and metamorphosizes to the adult form.

Predators: Fish and birds.

Conservation Status: No legal status but it is used as an indicator species for the health of sandy beaches.

Interesting Facts: Coquina clams are adapted to life within the wavy surf and can quickly bury themselves into the sand using their strong foot when they are exposed by receding waves.    These bivalves can live up to two years in the wild but can live only three days without the moving water that brings them plankton and detritus. The coquina can be consumed by humans.

On the Coast: Coquinas are one of the most abundant shells found on Georgia’s beaches.

Range/Geographical Distribution: Virginia to the Gulf of Mexico.

Habitat: Subtidal along beaches.

Description: A long, narrow, tapered shell with many whorls.  Colors vary from purple to yellow to brown to gray.  Small orange/yellow operculum.

Size: Can reach two inches in length.

Food: Worms

Breeding: No larval stage, young emerge from egg capsules and bury into the sand.

Predators: Moon snails, crabs

Conservation Status: No legal status.

Interesting Facts: When eastern auger snails die their shells often become homes for long-wristed hermit crabs.

On the Coast: Eastern auger shells are often found washed up on coastal Georgia’s beaches.

Range/Geographical Distribution: Maine to the Gulf of Mexico.  Introduced to the Hawaiian Islands.

Habitat: Intertidal and subtidal zones in brackish water estuaries and sounds.

Description: A variably-shaped bivalve that is gray/tan in color with unequal valves (shells).  The inside of each shell is white with a purple muscle scar.

Size: Can reach ten inches in length.

Food: Filter feeder; eats plankton.

Breeding: Sexual reproduction, spawns from late June to November. Females can produce up to 114 million eggs in a year. Larvae go through several planktonic stages before searching the substrate for a suitable place to setter. Larvae usually cement themselves to live or dead oyster or clam shells and then metamorphosize into a tiny oyster, called spat.

Predators: Crabs and mollusks.

Conservation Status: Not evaluated by the IUCN list.

Interesting Facts: Oyster beds provide habitat for other organisms and serve as a water filter by removing particulates along with the plankton that they consume.  Oysters can live for 20 years but current populations are thought to be about 1% of the historic population.  Massive harvesting, disease, and polluted waters have contributed to the decline in numbers.

On the Coast: Oyster beds are visible in most Georgia estuaries during low tides.  These gray mounds are found along the edges of the marsh and are covered with water during high tide.  Oyster shells commonly wash up on the beaches as well.

Range/Geographical Distribution: Virginia to the Gulf of Mexico and Brazil.

Habitat: Subtidal sandy bottoms.

Description: Slender gray or blue/gray arms with a dark midline down each arm.  Tube feet orange/yellow.

Size: Can reach a foot in diameter.

Food: Other echinoderms, worms, crustaceans, bivalves, detritus, and dead animal material.

Breeding: Spawns annually and has one larval stage.

Predators: Fish and crabs.

Conservation Status: No legal status.

Interesting Facts: Gray sea stars can ingest sand and mud along with their food and then strain the inedible material out through oral spines.  Some adults have a commensal polychaete worm that lives in a groove on the underside of the arm.

On the Coast: Gray sea stars are common along the Georgia coast but are rarely seen due to their habit of burying in the sand.  They do occasionally wash up onto the beach after strong storms.

Range/Geographical Distribution: From Cape Cod to the Gulf of Mexico.

Habitat: Subtidal along muddy and sandy beaches or estuaries.

Description: A medium-sized sea cucumber that is dark green/brown in color, swollen in the middle, and covered with tube feet.

Size: Can reach six inches in length.

Food: Consumes detritus and can directly absorb free amino acids from sea water.

Breeding: Separate sexes, external fertilization.  Larvae are planktonic before settling into the substrate.

Predators: The unsavory skin and genitals of sea cucumbers keep most predators away.

Conservation Status: No legal status.

Interesting Facts: When threatened by a predator, sea cucumbers can eject their viscera in a sticky mass that entangles and confuses the predator.  The viscera are then regenerated within a few weeks.

On the Coast: Hairy sea cucumbers often wash up onto Georgia’s beaches.  The sandy surf can wear away the tube feet so that these animals look like a swollen brown blob on land.

Range/Geographical Distribution: Cape Cod to the Caribbean.

Habitat: Shallow marine waters attached to hard substrates like shells and jetties.

Description: Thin, translucent-shelled bivalve with highly variable colors from black to silver to yellow to orange.  The lower shell has a hole in it where byssal threads protrude to attach the animal to its substrate.

Size: Can reach three inches in diameter.

Food: Filter feeder; eats plankton and detritus.

Predators: Other snails, fish, and crabs.

Conservation Status: No legal status.

Interesting Facts: The name of this clam comes from the sounds that a collection of shells makes when rattled together.  Although related to oysters, jingle clams have a bitter taste and are not good for human consumption.

On the Coast:  While live animals are rarely seen, jingle clam shells are often found along Georgia’s beaches.

Range/Geographical Distribution: Along the Atlantic coast from Cape Cod to middle Florida.

Habitat: Shallow waters including bays, beaches, and estuaries.

Description: The outer shell is gray/white to tan with some dark brown streaks and the inner shell is yellow, orange, or red.  The darkly colored soft body comprises the head, the visceral mass, and the foot (which is small). 

Size: Can reach 10 inches in length.

Food: Oysters, clams, and other marine bivalves.

Breeding:  Mate in the fall and females lay yellow, parchment-like strings of egg cases in deep water, anchoring one end in the sand. The string consists of up to 40 pouches, attached by a common heavy central cord. Each pouch may contain up to 100 fertilized eggs in a jelly-like material. The embryos are slow developing; the 1/8″ long hatchlings begin crawling out of the pouches the following year in late spring.

Predators: Sea turtles and blue crabs.

Conservation Status:  No legal status.

Interesting Facts:  Whelks are protandric hermaphrodites, which means they are initially males and then change into females as they age. The shell of the knobbed whelk can be made into a natural bugle by cutting off the tip of the spire to form a mouthpiece.

On the Coast:  The knobbed whelk is the state shell of Georgia and is common along the coast.

Range/Geographical Distribution: North Carolina to Gulf of Mexico and Brazil.

Habitat: Nearshore waters on shallow sand flats and near inlets.

Description: Shiny, cylindrical shell with chestnut-brown scrawled markings on it.  Has a low, pointed spire, four or five body whorls, and no operculum.

Size: Can reach three inches in length. 

Food: Coquina and other small, smooth-surfaced clams. 

Breeding: Lays 20-50 eggs on the sand in transparent capsules.  Eggs develop into veliger larvae within a week. The veligers break out of their capsule and live in a planktonic form prior to developing into adults.

Predators:  Birds, fish, and crabs.

Conservation Status: No legal status.

Interesting Facts: Native Americans made necklaces of these handsome shells and in the early 1900s they were collected and strung to make portières (door-curtains) to sell to tourists.  Sometimes common Atlantic slipper shells (Crepidula fornicata) can be found attached to the surface of a lettered olive, riding piggyback.

On the Coast: Lettered olive shells commonly wash up on Georgia’s beaches and are a prized favorite of beachcombers.

Range/Geographical Distribution: Along the coast from New Jersey to Texas. 

Habitat: Estuarine waters in creeks and among oyster beds. 

Description: Easily recognizable by the leftward spiraling shell.  Adults are grey with a glossy white aperture; juveniles have brown/orange “lighting-bolt” stripes that fade as they grow. 

Size: Can reach 16 inches in length. 

Food: Clams and other bivalves. 

Breeding: Mate in the fall and winter; fertilization is internal. Females lay strings of thick, disk-like egg capsules, up to a yard in length and an inch and a half in diameter, anchored in the sand. Juveniles grow slowly and hatch in three to 13 months.

Predators: Sea turtles, and blue crabs.

Conservation Status:  No legal status.

Interesting Facts:  When sea water temperature are outside of the optimum range of 77-82˚F, feeding rates and crawling speeds of lightning whelks decrease.

On the Coast:  Lightning whelks are less common than other whelks along the Georgia coast but their shells can be found washed up on the beaches.

Range/Geographical Distribution: From Greenland to the West Indies.

Habitat: Inshore and offshore waters along the coast.

Description: Round, translucent, white jelly with four distinct horseshoe-shaped gonads in the middle of the bell.

Size: Can reach ten inches in diameter.

Food: Plankton.

Breeding: Reaches sexual maturity during the spring and summer. The eggs develop in gonads located underneath the stomach.

Predators: Sea turtles, fish, birds, and other jellies.

Conservation Status: No legal status.

Interesting Facts: Moon jellies swim by pulsations of their bell in order to stay near the surface and keep their tentacles spread out to catch food.

On the Coast: Moon jellies are found along the Georgia coast in the summer and fall.  They can be seen in the water and washed up onto the beach in a gelatinous blob.

Range/Geographical Distribution: Massachusetts to the Gulf of Mexico. 

Habitat: Sandy, shallow waters in the intertidal and subtidal zones. 

Description: A large, gray/tan shell with several whorls.  The center of the shell is often dark blue or purple. The snail’s soft body is large and will conceal the entire shell when it is outstretched. 

Size: Can reach three inches in diameter. 

Food: Other mollusks.

Breeding: Sexual reproduction.  Females lay eggs in a sticky mass of jelly over their shell.  A layer of sand sticks to the collar and thickens it in order to protect the eggs.  Larvae are released into the water as plankton once they hatch.

Predators: Larger snails, including other moon snails, birds, fish, and crabs.

Conservation Status: No legal status.

Interesting Facts: Moon snails drill a countersunk, circular hole in the shell of their prey and then consume the soft body with their proboscis.

On the Coast:  Moon snails are common along the Georgia coast but it is the empty shells that are usually seen washed up on the beaches.  You may also encounter evidence of moon snails by finding small holes drilled in other shells laying on the beach.

Range/Geographical Distribution: North Carolina to Florida and the West Indies.

Habitat: Shallow waters with sandy or muddy bottoms.

Description: Large bivalve with a thin, fragile, wedge-shaped shell that is yellow/brown or purple/black.

Size: Can reach one foot in length.

Food: Filter feeder; eats plankton and detritus.

Predators: Whelks and crabs.

Conservation Status: No legal status.

Interesting Facts: The byssal threads—which hold a pen shell in place in the sand or mud—of a Mediterranean species of pen shell were once used by humans to weave garments such as gloves.  The mussels of pen shells are sold as “scallops” in some markets.

On the Coast: Pen shells commonly wash up on Georgia’s beaches but are rarely whole.

Range/Geographical Distribution: Massachusetts to the Gulf of Mexico.

Habitat: Shallow mud and sand flats with shell debris or gravel.

Description: Plummed worm casings are the end of a long tube that a polychaete worm occupies.  The red/gray/brown leathery tube is made of mucus, shells pieces, and rocks or sand.  The worm itself looks like a Christmas tree because of all of its “plumes” or gills, but it is rarely seen.

Size: Tubes can reach three feet in length and the worms that inhabit them can grow to a foot long.

Food: Predators; worms consume small fish and other animals that come within reach of their tube.

Breeding: Sexual reproduction, eggs are laid in a gelatinous mass.

Predators: Fish, crabs, and birds.

Conservation Status: No legal status.

Interesting Facts: Plummed worms can regenerate lost limbs or tissue after predation.

Range/Geographical Distribution: Worldwide in tropical and subtropical waters.

Habitat: Floats on the surface of ocean waters.

Description: This floating hydrozoan has an air-filled bladder and long, blue tentacles that trail along in the water.

Size: The tentacles can reach 165 feet in length.

Food: Fish, shrimp, crabs, other crustaceans, and plankton.

Breeding: Dioecious, sexual reproduction occurs in the fall and the gametes are released into the water.

Predators: Fish and crustaceans.

Conservation Status: No legal status.

Interesting Facts: The Portuguese man of war resembles an 1800’s war ship sailing in the water, hence the common name.  Although it looks like a sea jelly this animal is actually a colony of organisms living together, including the gas-filled bladder (pneumatophore), the tentacles (dactylozooids), feeding structures (gastrozooids), and reproductive structures (gonozooids).

On the Coast: The Portuguese man of war sometimes washes up on Georgia’s beaches.  It has a powerful sting and even dead organisms can sting.  If you are stung, do not use an acidic liquid to clean the area such as vinegar because this will activate more stinging cells and increase the pain.

Range/Geographical Distribution: Found from Cape Cod to the West Indies.

Habitat: Rocky or shell substrates.

Description: A small, round urchin with a tan/gray body and white spines tipped with purple.

Size: The test (body) can reach two inches in width.

Food: Grazes on algae and other organisms found on hard surfaces.

Breeding: Separate sexes; males and females release sperm and eggs into the water.  The fertilized eggs settle and hatch into larvae.

Predators: Long spines protect urchins from most predators.

Conservation Status:  No legal status.

Interesting Facts:  Sea urchins are radially symmetrical and feed with a special structure at the bottom of their body called an Aristotle’s lantern.  This “lantern” consists of five plates that move like a beak in order to scrape the algae off of rocks and the plates can grow back after too much wear.

On the Coast:  Live sea urchins are rarely seen but their test (body) often washes up onto Georgia’s beaches after they die.

Range/Geographical Distribution: Gulf of St. Lawrence to Florida and the Gulf of Mexico.  Introduced in England.

Habitat: Shallow waters with sand or muddy bottoms.

Description: A dull gray clam with a thick shell that has closely spaced concentric lines.

Size: Can reach six inches in width.

Food: Filter feeder; eats plankton and detritus.

Breeding: Quahogs are protandric hermaphrodites, which means they are initially males and then about half of the clams change into females as they age.  Spawning occurs during the summer and the planktonic larvae are free floating for about two weeks before settling.

Predators: Crabs, fish, birds, and whelks.

Conservation Status: No legal status.  Recreational fishermen in GA are limited to one bushel of clams per person and per boat per day.

Interesting Facts: For harvesting, clams are classified by size.  Those that are two to three inches are called littlenecks, those three to four inches are termed cherrystones, and clams over four inches are quahogs, which are used mostly for stews and chowders.

On the Coast: Quahog clams are found buried in the sediment along the estuaries and beaches on Georgia’s coast.

Range/Geographical Distribution: From the Gulf of St. Lawrence, Canada to Florida and the Gulf of Mexico.  Introduced in some places along the west coast of the United States.

Habitat: Tidal saltmarsh banks and flats.

Description: The thin, oblong shell is grooved and an olive/brown to brown/black color.

Size: Can reach four inches in length.

Food: Filter feeder; eats plankton and detritus.

Breeding: Separate sexes can be determined by color, females are brown whereas males are yellow/cream during breeding.  Mussels are broadcast spawners and release eggs and sperm into the water at synchronized times during the summer.  The fertilized eggs go through a planktonic stage before attaching to solid objects such as oysters or saltmarsh plants and transforming into a shelled form.

Predators: Crabs, whelks, and birds.

Conservation Status: No legal status.

Interesting Facts: Ribbed mussels can live for 15 years and you can determine their age by counting the ribs on the shell.  They can filter almost two gallons of water each hour.

On the Coast: In Georgia, ribbed mussels are often found in the saltmarsh attached to the stem of smooth cordgrass by their byssal threads.  This mutualistic relationship provides the mussel with an attachment site and the mussels’ fecal matter helps to feed the cordgrass.

Range/Geographical Distribution: All along the Atlantic coast, individual species are difficult to distinguish.

Habitat: Shallow waters near beaches and within estuaries.

Description: A rubbery, brown/white colonial bryozoan that attaches to hard substrates and encrusts other organisms such as sea whips or sea weeds. 

Size: Colonies can reach about one foot in diameter and branches may be a half an inch thick.

Food: Suspension feeder; eats plankton.

Breeding: Reproductive habits of rubbery bryozoan are unknown.

Predators: Fish, crabs, and sea urchins.

Conservation Status: No legal status.

Interesting Facts: Each individual zooid or polyp within the bryozoan colony has 14 tentacles that filter phytoplankton from the water at a rate of about nine milliliters per day.

On the Coast: Pieces of rubbery bryozoan colonies often wash up on Georgia’s beaches.

Range/Geographic Distribution: From Virginia to Brazil. 

Habitat: Shallow, sandy waters along beaches and bays. 

Description: A round, flat echinoderm with five oval holes called lunules.  The body of live sand dollars is gray/green and covered in tiny spines and tube feet.  After death, sand dollar tests (shells) lose the spines and tube feet and are white in color. 

Size: Can reach three inches in diameter. 

Food: Detritus, microorganisms, algae, and crustaceans.

Breeding:  Breed in the spring and summer.  Reproduce by sexual, external fertilization and the fertilized eggs hatch into planktonic larvae.  After about six weeks, the larvae metamorphosize into juveniles and settle onto the substrate.  

Predators: Sea stars, crabs, flounder, haddock, cod, and other bottom feeding fish.

Conservation Status:  Tybee’s city ordinance prohibits removing live sand dollars from the beach. 

Interesting Fact: Sand dollars, also called key-hole urchins, can live for ten years.  These echinoderms can only right themselves after being turned over by burying vertically into the sand.  The holes, or lunules, in a sand dollar’s body help to keep it from being swept away by waves.

On the Coast:  Live sand dollars are sometimes seen along the surf but should never be collected.  The bleached-white tests of dead sand dollars often wash up onto Georgia’s beaches and are a favorite for beachcombers.

Range/Geographical Distribution: From North Carolina to Brazil, but not the Gulf of Mexico.

Habitat: Along the coast on sandy substrates.

Description: The sea pansy is a small, petal-like frond covered in polyps with a thick purple stem that anchors the organism into the sand.

Size:  Can reach a total length of three inches, with the frond reaching a diameter of two inches.

Food:  Suspension feeder; eats plankton.

Breeding:  Can reproduce asexually by budding or sexually by releasing gametes.

Predators: Striped sea slug.

Conservation Status: No legal status.

Interesting Facts: The sea pansy displays a green bioluminescence when it is disturbed.  The purple color and rigidity of the sea pansy’s body is due to the presence of calcium carbonate spicules within its tissues.

On the Coast:  Sea pansies are common along the shallow sandy areas of Georgia’s coast, especially during the winter months.

Range/Geographical Distribution: Bay of Fundy to the Gulf of Mexico.

Habitat: Subtidal, growing on hard substrates to 30 feet deep.

Description: Rounded, hard, rubbery colonies that are pink or white in color.

Size: Colonies can reach a foot in width and an inch or more in height.

Food: Suspension feeder; eats plankton.

Breeding: Hermaphrodite, releases eggs and sperm into the water where they are fertilized.

Range/Geographical Distribution: New Jersey to the Gulf of Mexico.

Habitat: Attaches to rocks, reefs, pilings, shells, and other hard surfaces in shallow coastal waters.

Description: This branch-like coral is covered in polyps and has highly variable coloration, including purple, yellow, red, and white. 

Size: Can reach three feet in height.

Food:  Suspension feeder; eats plankton.

Breeding:  Reproduces sexually by external fertilization.  Planktonic larvae float for up to 20 days before settling on a hard surface.  After attachment, the larvae morph into a form that more closely resembles the adult.

Predators:  Nudibranchs and burrfish.

Conservation Status: No legal status.

Interesting Facts:  Sea whips are considered octocorals because they possess eight tentacles on each polyp. 

On the Coast:  Pieces of sea whip colonies often wash up on Georgia’s beaches.  The colored parts are recently dead and the black parts are the sea whip’s skeleton.

Range/Geographical Distribution: Along the Atlantic coast and the Gulf of Mexico.

Habitat: Skates live along the bottom of the ocean and lay their egg cases attached to the substrate.

Description: A small black rectangle with a curly horn in each corner.  This egg case comes from a skate, a vertebrate, cartilaginous flat fish common along the coast.

Size: Can reach four inches in length.

Food: The egg case contains yolk for the young fish to feed on and the horns of the case extract oxygen from the water and release waste from the case.

Predators: The leathery case protects the young skate from predators.

Conservation Status: No legal status.

Interesting Facts: Skate egg cases are made of collegen and are sometimes called mermaid’s purses.

On the Coast: Skate egg cases often wash up on Georgia’s beaches but they are usually empty because the young fish has already hatched.

Range/Geographical Distribution: Southeastern United States.

Habitat: Intertidal sand flats.

Description: A gray, slim, flexible tube covered in sand that resembles a soda straw in appearance.  The worm that inhabits the tube is pink and has well developed jaws.

Size: The worm that makes these tubes can reach 28 inches in length.

Food: Unknown.

Breeding: Unknown.

Predators: Birds, crabs, and fish.

Conservation Status: No legal status.

Interesting Facts: Two other species of worms live with soda straw worms and use hydrogen sulfide oxidation as a source of energy.

On the Coast: Soda straw worm casings wash up on calm, protected parts of Georgia’s beaches, sometimes by the hundreds, and can look like trash along the water line.

Range/Geographical Distribution: Worldwide.

Habitat: Most brackish and marine habitats.

Description: Porous body with variable shapes and colors.

Size:  Variable, colonies are usually less than two feet.

Food: Suspension feeder; eats plankton.

Breeding: Reproduce asexually by budding.  Sexual reproduction occurs when sponges release male gametes into the water and they are captured by neighboring sponges, which use them to fertilize eggs.

Predators: Sea turtles, crabs, mollusks, fish, and worms.

Conservation Status: No legal status.

Interesting Facts: There are 5000 species of sponges worldwide and most are marine.  Sponges have skeletons made of collagen and either calcareous or siliceous spicules.  They can contain toxic substances and other animals take advantage of this by placing sponges on their bodies.

On the Coast: Sponges are common along Georgia’s coast and pieces frequently wash up on the beach.

Range/Geographical Distribution: Native to the Pacific coast from California to Ecuador but is now found along the east coast from North Carolina to the Gulf of Mexico.

Habitat: Hard substrates such as rocks, pilings, and boat hulls; usually in high salinity locations.

Description: A large acorn barnacle with pink and light pink coloration on its shell.

Size: Can grow to two inches in height and width.

Food: Suspension feeder; eats plankton.

Breeding: Simultaneous hermaphrodites but breed with neighboring individuals.  Fertilization is internal and released larvae go through several planktonic stages before settling and metamorphosizing into an adult.

Predators: Large size protects them from most predators.

Conservation Status: No legal status.

Interesting Facts: Titan acorn barnacles have a body mass that is up to 100 times greater than native barnacles.  This increased size can be detrimental to native species as the titan barnacles out-compete natives for both food and space.  Titan acorn barnacles, also called giant pink barnacles, were first observed outside their native range in 1851 on the hull of a ship at Le Havre, France.

On the Coast: Titan acorn barnacles were first found in GA in 2006.  They can now be found on the pilings and rocks around Tybee Island.

Range/Geographical Distribution: Cape Cod to Florida and the Gulf of Mexico.

Habitat: Shallow waters including bays, beaches, and estuaries.

Description: A long strand of parchment-like disks that resembles a necklace.

Size: Can reach 40 inches in length.

Food: When whelk eggs hatch inside the capsules, the tiny whelks cannibalize each other before eating their way out of the casing.

Breeding: Whelk egg cases are anchored in the sand and each disk can contain 25 or more eggs.

Predators: The leathery egg case protects juvenile whelks from outside predation.

Conservation Status: No legal status.

Interesting Facts: Each whelk species lays distinctly different shaped capsules.  Knobbed whelk egg capsules have squared-off edges whereas channeled whelk capsules are sharp edged.

On the Coast: Whelk egg cases commonly wash up on Georgia’s beaches but most of the time the tiny whelks have already hatched and crawled away.