Blue Crab

The blue band hermit crab ( Pagurus samuelis) is a species of hermit crab it is usually found on the west coast of North America, and the most common hermit crab in California’s coast. It is a small species, with blue bands on its legs. The habitat it lives in its rocky costal short. This is what the name derives from due to its blue stripes. It prefers to live in the shell of the black turban snail. The length of the blue band hermit crab is 40 mm (1.6 in) and a carapace width of up to 19 mm (0.75 in). The carapace is the upper exoskeleton or shell of arthropods such as crustaceans. The color of the exoskeleton is brown or green, but the antennae are red, and adults have bright blue bands near the tips of their legs. In smaller individuals, the bands may be white. The legs and carapace are covered in setae, and the rostrum at the front of the carapace is triangular. The blue band hermit crab reproduces in June and July near the summer time in northern waters. The male grasps female’s shell and may carry her around for a day or longer, occasionally knocking his shell repeatedly against hers. Mating only last for a few seconds; both animals must nearly leave their shells to mate.

There fore leaving the hermit crabs exposed to predators. Eggs are produced from May to July, and are carried on the female’s abdomen; inside the shell. The life span is usually around 10-30 years. Hermit crabs mate externally when the male deposits sperm that the female absorbs into her body with secretions. The female lays her eggs within days or months after fertilization. The eggs appear in a ribbon-like grouping that remain attached to the female for approximately one month before the mother deposits the eggs in salt water to hatch. When hermit crab eggs hit salt water, they immediately open to produce small larvae-like or plankton swimming creatures called zoea. They develop by in stages, each stage lasting about a week. At each molt, they grow larger and add more appendages.

Life as a zoea lasts anywhere from 40 to 60 days or longer. In this stage the water temperature is 17 degrees Celsius, when the zoea molt into a post larval stage called a megalops. While in the water, they search for shells to live in. After another month or more, they metamorphose into juvenile land hermit crabs. Sand to molt during which time they shed their exoskeletons. It takes around 10 days for a new exoskeleton to harden. At the juvenile stage, the crabs now fully resemble hermit crabs and live only on land in borrowed shells. By the second year, most species have passed through a “puberty molt” and developed the structures necessary for reproduction and can be considered adults. Hermit crabs continue to grow and seek larger shells in which to make their home.

The blue band hermit crabs diet consists of algae and sometimes dead fish. They are nocturnal scavengers .In other words they feed at night and graze the floor and rocks for something to eat.

Interesting facts about the blueband
* Hermit crabs have 5 pairs of legs. This means they have 10 legs!. * There are 800 species of hermit crabs and 6000 species of regular crabs. * If hermit crabs are kept underwater too long, they will drown. * Hermit crabs have gill that must be keep moist or wet to survive. * When the hermit crab gets too big for its shell, it moves to another one. * It is not easy to detect if a hermit crab is a male or a female. * Hermit crabs spend most of their time and energy finding and retaining their snail shell. * Hermit crabs are scavengers and do not kill snails to use the shell.

The defense mechanisms of the blueband hermit crab are the shell. The claw is too small to help defend the hermit crab. The blueband hermit crab is a scavenger does not hut its food. The way the hermit crab eats it grabs its food with its pincers. It eats the food with its mouth and leads to its stomach.

References:

http://www.wallawalla.edu/academics/departments/biology/rosario/inverts/Arthropoda/Crustacea/Malacostraca/Eumalacostraca/Eucarida/Decapoda/Anomura/Family_Paguridae/Pagurus_samuelis.html * www.sanctuarysimon.org/species/species_info.php?speciesID=853&… * eol.org/pages/345024

* greennature.com/gallery/intertidal-animals/hermit-crab.html * stinkywinkie.com/Fitzgerald/pages/crabs_shrimp.htm