Case Study: Sacculina Carcini

crab’s scientific name is the Uca. Next the the fiddler crab lay thousands of eggs in one time. Did you know that you can buy a fiddler crab at pet store? Next time you go to a pet store look for the fiddler crab.

Ray McClain). The ‘farmed’ and the wild crawfish are both composed of the same species, the red swamp crawfish (Procambarus clarkii) and the white river crawfish (P. zonangulus). The more popular of the two crustaceans the red swamp crawfish, as it is caught more often is purchased more at the market. There are other crustaceans that are important to the basin besides crawfish, however. Blue crabs (Callinectes sapidus) are a vital resource in Louisiana’s seafood industry. The crabs are harvested by way of traps. In the case that the traps are lost or abandoned, they will continue to catch crabs. This is leading to a downturn in the blue crab population. Fish are also affected by the traps, as they are also caught. Despite the risked to the crab population, , the Marine Stewardship Council recognized the Louisiana blue crab fishery as the only sustainable blue crab fishery in the world in March of

Crabs spawn near the mouth of the Bay in Virginia water, therefore few sponge crabs (female crabs carrying eggs) are seen in Maryland (“Chesapeake Wildlife”). Juvenile crabs migrate northward to feed and grow in the brackish creeks of the Tidewater.

The Callinectes sapidus also known commonly as the Maryland Blue Crab, is a crustacean found in the Chesapeake Bay. The blue crab is found in aquatic environments, most often in estuaries. It characterized by it’s blue claws. The blue crabs undergo a life cycle of: zoeae, megalop, juvenile, and adulthood. The blue crab’s hard shells serve as a protective barrier for external dangers. The Callinectes sapidus comes from the order of Decapods, whereby it’s carapace has now evolved to be better suited for swimming. Of interest is the blue crab’s mating

Horseshoe crabs live in the Delaware Bay and give birth to their offspring there. At this time the red knots, a type of bird, migrate to the area to collect food. The food they collect is the newly conceived horseshoe crab eggs that are buried along the shore sand.

This species of communal crab only grows to a width of 1 inch, and has a square purplish body. The main source of food for these creatures are the leaves of marsh cordgrass, and the occasional smaller species of crabs like fiddler crabs. They are also nocturnal creatures, which makes them hard to study. Predators of this species include the Blue Crab, Striped Bass, and certain species of marsh birds.

Green Crab: This crab has been carried all over by ships. It eats many forms of shore life, including worms and mollusks. In certain areas, due to the appetite of the crab, it has affected the commercial shellfish industry.

In fact, even in ecosystems where Gemma gemma was the most numerically dominant macroinvertebrate, it was largely avoided and virtually excluded from the diet of horseshoe crabs (Botton, 1984). Also, because there is a size inequality between male and female horseshoe crabs, it is thought that the diets of male and female crabs may differ. Females are much larger than males, which could enable the females to feed on larger prey. Females also dig deeper into the substrate than males, which could give them access to fauna that is unavailable to males (Botton,

Horseshoe crabs have been on the earth since 30 million years ago which is before the dinosaurs lived. The Delaware Bay has the biggest population of horseshoe crabs in the world. In Delaware, the horseshoe crab population has decreased rapidly which is a problem for the environment. Many shorebirds that migrate, rely on horseshoe crab eggs for food. Also, the biomedical industry depends on horseshoe crabs for the substance, Limulus Amoebocyte Lysate(LAL) that is found in the blood of horseshoe crabs. Finally, fisheries use horseshoe crabs as bait for eels and whelk. Delaware researches and protects horseshoe crabs to benefit the environment and humans.

Shells before 1884, were high-spiraled with thin walls. Compared to the shells found after 1884 were low-spiraled with thick walls. After doing some research, Seeley found that an intertidal crab, Carcinus maenas, had sought after the snails for food.(Seeley) It was found that the shell size had changed due to the harmful

The blue crab, Callinectes sapidus, is one of the most familiar inhabitants of marshes and waterways along the Atlantic and GMx coasts of North America. The abundance of blue crab larvae and juveniles make them important components of the diets of numerous species of fish, invertebrate and avian predators (Van Engel 1987, Guillory and Elliot 2001). As juveniles and adults, blue crabs act as generalist predators on benthic infauna and epifauna; consuming invertebrates, fish, and crustaceans (including other blue crabs) as well as plant and detrital materials (Darnell 1958, Alexander 1986, Meise and Stehlik 2003, Lipcius et al. 2007). It has been proposed that blue crabs are keystone species in the marsh because of their impact as predators

Additionally, the Callinectes sapidus, otherwise known as the blue crab is another native species of the Chesapeake bay. It's decline has been quite evident to the bay and has many effects. With the oysters in the bay, the crab population had been cut by half, from 1980-1990, to 300 million. In 2008, it was reported that the population was declining by 70%. It was quite evident to the researchers that the blue crab population was decreasing due to poor water

The aim of the present study was to test the hypothesis that the invasive red king crab, Paralithodes camtschaticus, may hamper capelin recruitment through egg consumption, by carrying out fieldwork studies (2005, 2006), laboratory experiments (2011), and applying models of consumption. To explore the response of the predator to prey density, crab abundance and capelin egg density were estimated in stratified study areas. An exponential decay model was used to estimate stomach evacuation rates of capelin eggs in red king crab stomachs, and the average evacuation time estimated was 5.38 h at 2.9°C. The average evacuation time was applied to a consumption model where uncertainty in input values was assessed by Monte Carlo simulation. Estimated

Because LAL is only found in the horseshoe crab’s blood, there is no substitute and horseshoe crab blood must be used (Fabie, 2009). Authorized companies capture the adult (mainly female) horseshoe crabs, collect one third (30%) of their blood, and then release them back into the wild ( Fabie, 2009 FIND OTHER SOURCES). Until last year, the US Food and Drug Administration (USFDA) mandated the return of all bled crabs to the water within 72 h, but LAL producers now have the option of selling bled crabs to bait dealers (Botton, 2003).

The blue crab population in the Chesapeake Bay was considered to be a surplus from the 1950s to around the 2000s as well as in the Bay’s tributaries (Stagg & Whilden, 1997). The blue crabs in Maryland live for about three years (Stagg & Whilden, 1997). This is part of the reason that it’s so important that a high level of blue crabs is maintained so that they’ll be able to produce offspring future generations. Approximately 75% of the entire blue crab population is made up of the crabs in Maryland (Lui, 2015).