Horseshoe Crabs Research Paper

Green crabs are found in shallow ocean waters and they have a preference for sheltered areas. They are an aggressive and territorial crab species (CBC, 2012). Although this species is known as the “green crab”, they are not always green. In fact, this species of crab can range from a variety of colors such as red, orange, brown, blue and yellow; the colors often depend on when the crab last exuviated. Due to the fact that green crabs cannot be distinguished solely by color, they are often confused with other crab species such as the rock crab. A few ways to distinguish the European green crab from other crabs is by 5 pointy spines which are located on the front end of the carapace on either side of the eye as cited by GOV, (2013) and 3 rounded lobes located between the eyes. European green crabs are also distinguished by their claws of different sizes and the way the tips of its back legs are pointed, flattened and hairy. A European green crab generally doesn’t surpass 4 inches (appx. 100 mm) and an average green crab is approximately 2.5 inches (appx. 63 mm) (Peters et al. 2004). Male green crabs typically range from 40-70mm whereas female green crabs ranged from 40-65mm. If these crabs, male or female, surpassed their average size they were classified as old adults (Yamada and Gillespie, 2008). The adult green crab can survive out of the water for

Warren's Lobster House is located on the southern tip of Maine's coast and serves the freshest seafood, lobster and fish. The family-friendly restaurant also has chicken, steak and other seafood available. Warren's Lobster House is a destination restaurant perched on top of wood pilings above the waters of the Piscataqua River. It's located on US 1 and has been open since 1940.

Horseshoe crabs are an important part of the wetland ecosystem, however they are going extinct. Due to harvesting, pollution, and other animals consuming their offspring their numbers are dwindling. They play an important part in the ecosystem and need to be protected so they do not become extinct. The Delaware bay has decided to protect them for their future uses in medicine and to keep them as an important role in the ecosystem.

Three years ago, the author took a trip to Delaware. As his family was walking on the beach they came across some horseshoe crabs mating. He wondered how they have changed. The type of horseshoe crab he saw along the beach was called “limulus polyphemus”. Limulus Polyphemus is not found in the fossil records. The fossil record for horseshoe crabs is deeper than 20 million years, and the

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.

Recently, various user groups have relied on horseshoe crabs for bait and nutrition. While concerns have arisen that the horseshoe crab populations are declining, management of the American species of horseshoe crabs has been surrounded by controversy (Davis et al., 2006). Historically, horseshoe crabs have been considered a “trash-fish”, not worthy of resources to establish their population data. As a result, reporting regulations and harvest restrictions associated with this fishery have been lacking (Baker et al., 2004).

Horseshoe crabs are considered “living fossils” or evolutionary survivors because the external appearance barely changed in over 150 million years. The horseshoe crab is part of the arthropods, which include organisms such as spiders and scorpions. The horseshoe crab is made up of the prosoma, which is the head, opisthosoma, which represents the central part of the body and the telson, which is the tail. The tail is harmless and is only used to help the crab flip itself over if it’s turned over on the wrong side. Horseshoe crabs have been researched numerous times. Findings include their, ancestry, survival, morphological changes (if any) and phylogenetic research among the different variations of horseshoe crabs.

An invasive species is a species that is not native to an area, and whose introduction often causes harmful environmental impacts. The European Green Crab, also known as Carcinus maenas, is an invasive species from Europe. It was introduced to the U.S. most likely by ballast ship water, El Nino, or by being shipped unnoticed in the kelp packing around lobsters/bait worms. The European Green Crab now inhabits the eastern and western coasts of the US, in addition to its native home and other invaded areas.

Some organisms are resistant to ageing and can be classified as biologically immortal. Cells that are not subject to the Hayflick limit (normal number of times cells divide until they stop) are considered biologically immortal. Hydra is a biologically immortal organism because it does not undergo cellular senescence as they regenerate their stem cells and have few different cell types. The American lobster Homarus americanus has large quantities of telomerase in its adult stage unlike most vertebrates which have an absence of this in their adult life; therefore the American lobster has an extended lifespan.

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.

The American horseshoe crab (Limulus polyphemus) has persisted largely unaltered for millions of years (Smith et al., 2006), and has ancestors that date back 450 million years ago (Swan, 2005). They belong to the genus Limulaceae, and are an ancient group of aquatic merostome arthropods (Sekiguichi, K., and Shuster J., 2011). Limulus polyphemus inhabits the eastern coast of the United States (Goode and Wahle, n.d., Swan, 2005). It ranges from the Yucatan Peninsula to the Gulf of Mexico (Moore and Perkin, 2007 (Shuster, 1979), about 42 to 19° N (Botton, 2003). Limulus polyphemus are found within estuaries, coastal embayments, and on the inshore continental shelves near the mouths of estuaries, usually in waters that are less than 30 meters

The lifespan of a horseshoe crab is up to 20-40 years in the wild. There structure has not changed much for the past 445 million years. One hypothesis is that the hard exoskeleton of horseshoe crab allows them to survive predators and as a result they have been to live through many decades. Horseshoe crabs have a unique and premature body structure which consists of a hard shell, referred to as a molt, which acts as their

They will eventually shift north as the area warms and becomes suitable for the tree’s growth, but in the meantime, there is a vast swath of the Aratus range in salt marshes instead of mangroves. Here the crabs’ main substrate is spartina. Aratus also revealed a shift in diet from mangrove leaves to more insect based consumption. This presents a curious case, as Aratus is highly dependent on the mangrove system for all aspects of life.

In this project I would be describing the Blue crab and the classification of the blue crab. I will also be describing the characteristics of the blue crab and also the structure of it. In this project I will also be describing the physiology and the life cycle, and interesting facts relating to the structure. I will also be discussing the reproduction and where the blue crab fits into the evolutionary tree and how it fit there. Crabs does are crustaceans with five pairs of legs. The first pair is modified as pinchers and the last four pairs are walking legs. The blue crab's shell is about 17.8 cm wide and 10.2 cm long. It weighs about 0.45 to 0.9 kg when fully grown. The back of the blue crab is dark or brownish green and is drawn out on each

The overarching question which continues to spark debate and curb efforts to protect invertebrates is that of whether they feel pain or simply exhibit nociception. The controversiality of this question is rooted in the obscurity of the definition of pain and what denotes a painful experience in an invertebrate. The International Association for the Study of Pain defines pain as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage” (Horvath et al. 10). In contrast, nociception is merely a body system’s instinctive reflex to noxious stimuli, which does not require the emotional perception of pain (Andrews 121). For instance, when a person places their hand on a hot stove, they immediately pull their hand away to