Means of Introduction: It is not known how this species was introduced to the United States Atlantic coast, but many speculate that adults or larvae were brought by incoming ships of global trade via ballast water discharge. Status: Preliminary evidence shows that rockfish and seagulls may prey upon Hemigrapsus. Parasites, which help control populations of Hemigrapsus in its native range, are not present along the US Atlantic coast. The shore crab may continue to expand its range along the US Atlantic coastline until it reaches its salinity and temperature tolerance levels. Ballast water management is also being researched to reduce or eradicate new introductions from occurring. Impact of Introduction: Because this species has a very broad diet, it has the potential to affect populations of native species such as crabs, fish, and shellfish by disrupting the food web.
|Published (Last):||15 December 2005|
|PDF File Size:||3.25 Mb|
|ePub File Size:||17.79 Mb|
|Price:||Free* [*Free Regsitration Required]|
Economic Impacts Impact: Hemigrapsus sanguineus Japanese Shore Crab appears to be limited to man-made rocky intertidal habitat jetties, bulkheads, etc. Because of its restricted distribution, it is unlikely to have significant economic impacts in Chespeake Bay.
References- Ruiz et al. However, because most major fisheries resources in this region are subtidal, economic impacts are likely to be small. Ecological Impacts Impacts on Natives: Competition Hemigrapsus sanguineus Japanese Shore Crab now occurs locally in jetties and other stone structures in lower Chesapeake Bay, but its abundance and impacts are limited by lack of rocky habitat Ruiz et al. In New Jersey, it has been considered a potential competitor with native crabs in the intertidal zone McDermott and a potentially important intertidal herbivore and predator in Long Island Sound Gerard et al.
Detailed field studies of interactions between H. In Long Island Sound CT , competition with native crab species is limited because the natives, primarily Eurypanopeus depressus, have little habitat overlap with H. Predation by high densities of H.
It is a competitor with Carcinus maenas Green Crab Jensen et al. However, the extent to which these species interact, in the Chesapeake Bay region, where all of them are in low abundance, is unclear. References- Brousseau et al.
Top of page Reproductive Biology Fully grown H. The eggs of H. The eggs hatch into larvae, which proceed to molt through five zoeal stages to become megalopae Hwang et al. Megalopae can be found in the water column or on the benthos Hwang et al. After settlement and metamorphosis, the first crab stage is usually between 1.
HEMIGRAPSUS SANGUINEUS PDF
Nirisar Sakai, ; Takada and Kikuchi, This can have serious consequences for the salt marsh ecosystem through both direct and indirect interactions. The barnacles and molluscs that H. The Asian shore crab is believed to have been introduced to the northwest Atlantic once or multiple times by ballast water discharged from ocean-going ships Epifanio et al. We chose to use both approaches to identify whether an emergent effect occurred and determine the direction of the effect.