Category Archives: Sanibel

Sanibel

SeaShell News: Seahorse, Shelling, Sanibel

SeaShell News, 4-27-15, Seahorse, Shelling, Sanibel.
SeaShell News, 4-27-15, Seahorse, Shelling, Sanibel.

SeaShell News, 4-27-15, Seahorse, Shelling Sanibel.

Seahorse is the name given to 54 species of small marine fishes in the genus Hippocampus. “Hippocampus” comes from the Ancient Greek hippos meaning “horse” and kampos meaning “sea monster”.[2] Having a head and neck suggestive of ahorse, seahorses also feature segmented bony armour, an upright posture and a curled prehensile tail.

Seahorses are mainly found in shallow tropical and temperate waters throughout the world, and live in sheltered areas such as seagrass beds, estuaries, coral reefs, or mangroves. Four species are found in Pacific waters from North America toSouth America. In the Atlantic, H. erectus ranges from Nova Scotia to Uruguay. H. zosterae, known as the dwarf seahorse, is found in the Bahamas.

Colonies have been found in European waters such as the Thames Estuary.[3]

Three species live in the Mediterranean Sea: H. guttulatus (the long-snouted seahorse), H. hippocampus (the short-snouted seahorse), and H. fuscus (the sea pony). These species form territories; males stay within 1 m2 (11 sq ft) of habitat, while females range about one hundred times that.

Seahorses range in size from 1.5 to 35.5 cm (0.6 to 14.0 in).[4] They are named for their equine appearance. Although they are bony fish, they do not have scales, but rather thin skin stretched over a series of bony plates, which are arranged in rings throughout their bodies. Each species has a distinct number of rings. Seahorses swim upright, another characteristic not shared by their closepipefish relatives, which swim horizontally. Razorfish are the only other fish that swim vertically like a seahorse. Unusual among fish, a seahorse has a flexible, well-defined neck. It also sports a coronet on its head, which is distinct for each individual.

Seahorses swim very poorly, rapidly fluttering a dorsal fin and using pectoral fins (located behind their eyes) to steer. The slowest-moving fish in the world is H. zosterae (the dwarf seahorse), with a top speed of about 5 ft (1.5 m) per hour.[5] Seahorses have nocaudal fin. Since they are poor swimmers, they are most likely to be found resting with their prehensile tails wound around a stationary object. They have long snouts, which they use to suck up food, and their eyes can move independently of each other (like those of a chameleon).

 

Source:  Seahorse.

SeaShell News: Tiger Lucine, Shelling, Sanibel

SeaShell News, Tiger Lucine, 4-19-15, Codakia orbicularis (tiger lucine clam) (San Salvador Island, Bahamas) 1 by James St. John, Via Creative Commons.
SeaShell News, Tiger Lucine, 4-19-15, Codakia orbicularis (tiger lucine clam) (San Salvador Island, Bahamas) 1 by James St. John, Via Creative Commons.

SeaShell News, 4-19-15, Tiger Lucine, Shelling, Sanibel Island.

Lucinidae is a family of saltwater clams, marine bivalve molluscs.

These bivalves are remarkable for their endosymbiosis with sulphide-oxidizing bacteria.[1]

The members of this family are found in muddy sand or gravel at or below low tide mark. They have characteristically rounded shells with forward-facing projections. The valves are flattened and etched with concentric rings. Each valve bears two cardinal and two plate-like lateral teeth. These molluscs do not have siphons but the extremely long foot makes a channel which is then lined with slime and serves for the intake and expulsion of water.[2]

Source:  Tiger Lucine.

 

SeaShell News: Atlantic Thorny Oyster, Shelling, Sanibel

SeaShell News, 4-13-15, Atlantic Thorny Oyster - hinge by FWC Fish and Wildlife Research Institute, Via Creative Commons.
SeaShell News, 4-13-15, Atlantic Thorny Oyster – hinge by FWC Fish and Wildlife Research Institute, Via Creative Commons.

SeaShell News, 4-13-15, Atlantic Thorny Oyster, Shelling, Sanibel Island.

The Atlantic thorny oyster can grow to 10 centimetres (3.9 in) in diameter. The valves of the shell are roughly circular and the upper one is decorated with many spiny protuberances up to 5 centimetres (2.0 in) long.

When growing in a crevice, the shape of the shell adapts itself to the available space.[3] The colour varies but is usually white or cream with orange or purplish areas making it well camouflaged. The lower valve is flat and is attached to the substrate. When the living animal is lying on the seabed it is usually not visible because of the algae, marine animals and sediment that cover the shell. The flat tree oyster and Lister’s tree oyster are often among these epibionts.[4] A diver swimming past may just observe a slight movement on the seabed as the oyster snaps its valves shut. Young animals are much less spiny than adults and resemble members of the genus Chama, the jewelbox clams.[5][6]

The Atlantic thorny oyster occurs in the western Atlantic Ocean, the Caribbean Sea and Gulf of Mexico where it is found at depths between 9 and 45 metres (30 and 148 ft). Its range extends from North Carolina and Texas southwards to Venezuela and Brazil. It occurs on deep water reefs especially in areas with high sedimentation. It is often lodged in a crevice or concealed under an overhang. It is also a member of the fouling community, being found on sea walls, man made structures and wrecks.[5][6]

Source:  Atlantic Thorny Oyster.

Seashell News: Atlantic Slipper Shell, Shelling, Sanibel

SeaShell News, 4-1-15, Atlantic Slipper Shell, Crepidula fornicata - Common Atlantic Slippersnail by Crabby Taxonomist, Via Creative Commons.
SeaShell News, 4-1-15, Atlantic Slipper Shell, Crepidula fornicata – Common Atlantic Slippersnail by Crabby Taxonomist, Via Creative Commons.

SeaShell News, 4-1-15, Atlantic Slipper Shell, Shelling, Sanibel Island.

The common slipper shell, Crepidula fornicata, has many other common names, including common Atlantic slippersnail, boat shell, quarterdeck shell, fornicating slipper snail, Atlantic Slipper Limpet and it is known in Britain as the “common slipper limpet“. This is a species of medium-sized sea snail, a marine gastropod mollusc in the familyCalyptraeidae, the slipper snails and cup and saucer snails.

The size of the shell is 20–50 mm.[1] The maximum recorded shell length is 56 mm.[2]

This sea snail has an arched, rounded shell. On the inside of the shell there is a white “deck”, which causes the shell to resemble a boat or a slipper, hence the common names. There is variability in the shape of the shell: some shells are more arched than others.

Groups of individuals are often found heaped up and fastened together, with the larger, older females below and the smaller, younger males on top. As a heap grows, the males turn into females (making them sequential hermaphrodites).[3]

The species is native to the western Atlantic Ocean, specifically the Eastern coast of North America. It has been introduced accidentally to other parts of the world and has become problematic.

Distribution of Crepidula fornicata ranges from 48°N to 25°N; 97.2°W to 25°W[1] from as far north as Nova Scotia to as far south as the Gulf of Mexico.[1]

It was introduced to the state of Washington.[1] The species was, however, brought to Europe together with the eastern oyster Crassostrea virginica.[1] In Belgium, the first slipper limpet was found on September 28, 1911, attached to an oyster inOstend, and since the 1930s it is seen as a common species along Belgian coast.[1]

The species is considered an invasive species in Denmark, France, Italy, the Netherlands, Spain, and the United Kingdom, and has also spread to Norway and Sweden.[4] It is known to damage oyster fisheries.[5] The slipper limpet has few to no predators in Europe, and can thrive on several types of hard bottoms and shellfish banks.[1] A continued expansion to the north is probably inhibited by temperature: low temperatures during the winter can slow down or inhibit the development of the slipper limpet.[1]

It has also been introduced to the Pacific Northwest and Japan.[6]

Source:  Atlantic Slipper Shell.

SeaShell News: Sea Urchin, Shelling, Sanibel

SeaShell News, 3-17-15, Sea Urchin, Ikiriya - Sea Urchin by Buddhima W. Wickramasinghe, Via Creative Commons.
SeaShell News, 3-17-15, Sea Urchin, Ikiriya – Sea Urchin
by Buddhima W. Wickramasinghe, Via Creative Commons.

SeaShell News, 3-17-15, Sea Urchin, Shelling, Sanibel.

“Sea urchins or urchins (/ˈərɪnz/), archaically called sea hedgehogs,[1][2] are small, spiny, globular animals that, with their close kin, such as sand dollars, constitute the class Echinoidea of the echinoderm phylum. About 950 species of echinoids inhabit all oceans from the intertidal to 5000 m deep.[3] The shell, or “test”, of sea urchins is round and spiny, typically from 3 to 10 cm (1.2 to 3.9 in) across. Common colors include black and dull shades of green, olive, brown, purple, blue, and red. Sea urchins move slowly, and feed on mostly algae. Sea otters, starfish, wolf eels, triggerfish, and other predators hunt and feed on sea urchins. Their roe is a delicacy in many cuisines. The name “urchin” is an old word for hedgehog, which sea urchins resemble.

Sea urchins have conquered most sea habitats, on an extremely wide range of depths.[32] Some species, such as Cidaris abyssicola, can live down to several thousands of meters deep. Many genera are totally indentured to the abyssal zone, such as many cidaroids, most of the genera in the Echinothuriidae family, or the strange genus Dermechinus. One of the deepest-living family is the Pourtalesiidae,[33] strange bottle-shaped irregular sea urchins that live only in the hadal zone, and have been collected as deep as 6850 meters deep in the Java trench.[34] Nevertheless, this makes sea urchin the class of echinoderms living the less deep, compared to sea cucumbers and crinoids that remain abundant below 8000m deep[34]

Sea urchins can be found in all climates, from the warmest seas to the freezing polar seas[32] (like the polar sea urchin Sterechinus neumayeri). They adapt their diet to their environment : in rich ecosystems they feed mainly on algae, that allow a quick growth ; at the contrary in less rich bottoms they adopt a slower metabolism, adapted to a less calorific diet.

The shingle urchin (Colobocentrotus atratus), which lives on exposed shorelines, is particularly resistant to wave action. It is one of the few sea urchin that can survive many hours outside from the water.[35]

Despite their presence in nearly all the marine ecosystems, most species are encountered on temperate and tropical coasts, between the surface and some tens of meters deep, close to photosynthetic food sources.[32]

Source:  Sea Urchins.

SeaShell News: Atlantic Deer Cowry, Shelling, Sanibel

Atlantic Deer Cowry By FWC Fish and Wildlife Research Institute, Via Creative Commons.
Atlantic Deer Cowry By FWC Fish and Wildlife Research Institute, Via Creative Commons.

SeaShell News, 3-16-15, Atlantic Deer Cowry, Shelling, Sanibel.

“Macrocypraea cervus, common name the Atlantic deer cowry, is a species of large sea snail, a very large cowry, a marine gastropod mollusk in the family Cypraeidae, the cowries.

This species is mainly distributed in the tropical Atlantic Ocean including the Caribbean Sea, and in the waters off South Carolina, Florida, Mexico, Brazil, Cuba and the Bermudas.

This species is one of the largest cowries. It is quite similar in shape and colour to Macrocypraea cervinetta, but it is much larger. The maximum recorded shell length is 190 millimetres (7.5 in), while minimum length is about 40 millimetres (1.6 in).

The shell is elongated, its basic colour is light brown, with small whitish ocellated spots on the dorsum, like a young fawn (hence the Latin namecervus, meaning ‘deer’). Juveniles have no spots. The dorsum also shows a few transverse clearer bands, and a longitudinal line where the two edges of the mantle meet. The apertural teeth are dark brown. The mantle of the living cowry is dark greyish and completely covered in short fringes.”

Source:  Atlantic Deer Cowry.

 

SeaShell News: Worm Shell, Shelling, Sanibel

SeaShell News, 3-10-15, Vermicularia, Worm Snail Shell, By James, Via Creative Commons.
SeaShell News, 3-10-15, Vermicularia, Worm Snail Shell, By James, Via Creative Commons.

SeaShell News, 3-10-15, Worm Shell, Shelling, Sanibel Island.

Vermicularia knorrii, common name Florida worm snail, is a species of sea snail, a marine gastropod mollusk in the family Turritellidae.[1]

Vermicularia knorrii has a shell that reaches a length or 20 – 80 mm.[2] The apex of this shell is pure white and translucent, while the later whorls turn to pale brown and shows prominent spiral cords. When it grows the shell becomes loosely and irregular coiled and the whorls do not touch each other any more.

This species can be found in Caribbean Sea and in Gulf of Mexico (especially in Yucatan, Florida, Bermuda, Cuba,Jamaica and Puerto Rico).

Source:  Worm Shell.

SeaShell News: Angel Wings, Shelling, Sanibel Island

SeaShell News, Shell Or Angel's Wings By Darijus Strasunskas, Via Creative Commons.
SeaShell News, Shell Or Angel’s Wings By Darijus Strasunskas, Via Creative Commons.

SeaShell News, 3-6-15, Angel Wings, Shelling, Sanibel Island.

“Pholadidae, known as piddocks or angel wings, are a family of bivalve mollusc similar to a clam; however, they are unique in that each side of their shells is divided into 2 or 3 separate sections. Furthermore, one of the piddock’s shells has a set of ridges or “teeth”, which they use to grind away at clay or soft rock and create tubular burrows. The shape of these burrows is due to the rotating motion of the piddock as it grinds the rock to make its home. The piddock stays in the burrow it digs for the entirety of its eight-year lifespan, with only its siphon exposed to take in water that it filters for food. When the piddock dies and leaves an empty tubular burrow, other marine life such as sea anemone, crabs and other molluscs may use the burrow.

Some species of Pholadidae may reach up to 18 cm (7″). Their coloration is typically white, though through consumption of red tide algae some may develop a pink coloration.

The angelwing species Cyrtopleura costata has approximately 26 radiating ribs. Growth lines run horizontally over the surface of the shell. Angelwings have a spoon-shaped brace under the beak of the shell, called the apophysis, where the mollusc’s foot muscles are attached. Cyrtopleura costatapossesses long siphons which protrude from its burrow and circulate water as the source for its food supply. It cannot retract its siphons into the protection of its shell, so the two valves can never shut completely.

The muscles fusing the shell’s valves together are weak, making it rare to find angelwings with both halves still intact. Some shell hunters dig for the living clam, and if dug up, the fragile shell must be placed immediately into a container of water or it will close and shatter. The angelwing’s shell is popular with collectors, as well as a delicious food staple. The angelwing lives offshore and in estuaries, sometimes as much as a metre (three feet) deep in the mud or clay.

Source:  Angel Wings.

SeaShell News: Bowman’s Beach, Sanibel Island

Seashell News, 3-1-15: Tons Of Shells On Bowman's Beach, Sanibel Island, By Gregory Moine, Via Creative Commons.
Seashell News, 3-1-15: Tons Of Shells On Bowman’s Beach, Sanibel Island, By Gregory Moine, Via Creative Commons.

SeaShell News, 3-1-15, Bowman’s Beach, Sanibel Island.

Bowman’s Beach is one of the premier shelling beaches on Sanibel Island.

“Sea shell collecting is varied here although when a storm has recently passed by it is excellent. The removal of shells from this beach is prohibited when they house living creatures.

The white sand on this beach is composed of fine pulverized quartz, which eroded from the Appalachian Mountains some 200 million years ago and was delivered to the Gulf by inland tributaries. Over time, wind and sea currents brought the material to its current location.

Bowman’s Beach, Sanibel Island, FL, is on an island that is home to around 6,000 full time residents and 12,000 part time inhabitants. From the beach itself, there is no sign of said habitation as not a single building can be seen from the sands. Only palm trees serve as a backdrop here.

The island where this beach is found has been rated to be among the ten best places in the U.S. for bird watching. A small trail can be hiked through the woods behind the beach that runs parallel to the shoreline.

Source:  Bowman’s Beach.

SeaShell News: Albino Scotch Bonnet, Sanibel Island

Albino Bonnet Seashell, 2-27-15, Sanibel Island, SeaShell News & Shelling.
Albino Bonnet Seashell, 2-27-15, Sanibel Island, SeaShell News & Shelling.

SeaShell News, 2-27-15, Albino Scotch Bonnet, Sanibel Island.

Rough water and wind has made the shelling superb the last couple of days.

“The Scotch bonnet (Semicassis granulata), also known as the ridged bonnet, is a medium-sized species of sea snail, a marine gastropod mollusk in the subfamily Cassinae.[13][14] The common name alludes to the general outline and color of the shell, which vaguely resemble a Tam o’ Shanter, a traditional Scottish bonnet.

This species is found primarily in the tropical and subtropical Western Atlantic Ocean, from North Carolina to Uruguay.[12] It is the most common species in this subfamily in North America. A similar-appearing sea snail in the Mediterranean SeaSemicassis granulata undulata, has been considered a subspecies. These sea snails are predators; they search for their food on sandy stretches of the ocean floor, where they consume echinoderms such as sand dollars, sea biscuits, and other sea urchins.[15]

In 1965, the shell of this species was named a state symbol of North Carolina, making this the first state to designate an official state shell.”  Source:  Scotch Bonnet.