The primary habitat of H. sanguineus in Japan is crevices among boulders on rocky intertidal shores (Fukui, 1988; in Gerard et al. 1999). In the Western Pacific the distribution of H. sanguineus ranges from ~20 to 50 N latitude including Hong Kong and Taiwan, the Chinese and Korean coasts, and all of Japan (Mcdermott, 1998).
Ledesma and O'Connor (2001) states that, \"Mcdermott (1998a) suggested that the length of the reproductive period of H. sanguineus is related to latitude and therefore water temperature. In southern parts of Japan, the breeding season is 8 months long (Fukui 1988), whereas in northern Japan, it lasts 3 months (Takahashi et al. 1985). Whereas breeding occurred through September at Gooseberry in Buzzards Bay, ovigerous females were found only until early August in Sandwich in Cape Cod Bay.\"
Principal source: Brousseau et al. 2001. Laboratory investigations of the effects of predator sex and size on prey selection by the Asian crab, Hemigrapsus sanguineus.
Benson, 2005. Nonindigenous Species Information Bulletin Asian shore crab, Japanese shore crab, Pacific crab, Hemigrapsus sanguineus (De Haan) (Arthropoda: Grapsidae).
Compiler: National Biological Information Infrastructure (NBII) & IUCN/SSC Invasive Species Specialist Group (ISSG)
Review: Dr Greg Jensen
Publication date: 2006-11-16
Recommended citation: Global Invasive Species Database (2024) Species profile: Hemigrapsus sanguineus. Downloaded from http://www.iucngisd.org/gisd/speciesname/Hemigrapsus+sanguineus on 01-09-2024.
The intertidal distribution of H. sanguineus overlaps that of juvenile (non-native) green crabs (Carcinus maenas), particularly in the northern part of their range. Furthermore, H. sanguineus is dependent on rock cover and anecdotal reports suggest C. maenas has become uncommon under rocks in some areas since the arrival of H. sanguineus (Jensen et al. 2002). It is debatable whether there is evidence that H. sanguineus is negatively impacting on native crabs (G. Jensen, pers. comm.). Brousseau et al. (2003) found that mud crabs were actually competitively dominant over H. sanguineus.
Laboratory studies have shown that H. sanguineus readily consumes three species of commercial bivalves: blue mussels Mytilus edulis, soft-shell clams Mya arenaria, and oysters Crassostrea virginica (Brousseau et al. 2001; Benson, 2005). The high densities of H. sanguineus which occur in the wild, their effectiveness as predators of juvenile bivalves and their large appetites suggest an important role for these predators in restructuring the prey communities in habitats into which they have been introduced (Brousseau et al. 2001).
Biological: It is possible that species such as tautogs, drums, sheepshead and seagulls prey upon H. sanguineus (Benson, 2005; G. Jensen, pers. comm.). Parasites, which help control populations of H. sanguineus in its native range, are not present along the US Atlantic coast (Benson, 2005).