The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
John J Mcdermott - One of the best experts on this subject based on the ideXlab platform.
-
ectosymbionts of the non indigenous asian shore crab Hemigrapsus sanguineus decapoda varunidae in the western north atlantic and a search for its parasites
Journal of Natural History, 2007Co-Authors: John J McdermottAbstract:Over 560 Asian shore crabs, Hemigrapsus sanguineus, collected mainly in the spring of 2005 and 2006 from rocky intertidal locations in southern New Jersey, were examined for epibionts. Small numbers of the sympatric green crab, Carcinus maenas, and the Atlantic mud crab, Panopeus herbstii, were examined for epifauna to compare with H. sanguineus. Blue mussel spat, Mytilus edulis, and the encrusting, cheilostome bryozoan, Conopeum tenuissimum, were the dominant ectosymbionts of the shore crab, with prevalences of 22.2 and 32.1%, respectively; ranges of intensity were 1–146 spat/crab and 1–31 colonies/crab. Both species are incidental symbionts. Larger crabs had higher prevalences and intensities of C. tenuissimum colonies, and these colonies displayed a distinct pattern of attachment to the carapace which seemed to be related to crab morphology and habitat. Much less common was the encrusting, ctenostome bryozoan Alcyonidium albescens, a facultative symbiont species with a prevalence of 3.4%. Other epibion...
-
the western pacific brachyuran Hemigrapsus sanguineus grapsidae in its new habitat along the atlantic coast of the united states geographic distribution and ecology
Ices Journal of Marine Science, 1998Co-Authors: John J McdermottAbstract:McDermott, J. J. 1998. The western Pacific brachyuran (Hemigrapsus sanguineus: Grapsidae), in its new habitat along the Atlantic coast of the United States: geographic distribution and ecology. ‐ ICES Journal of Marine Science, 55: 289‐298. The Asian shore crab, Hemigrapsus sanguineus (de Haan, 1853), discovered on the coast of New Jersey in 1988, is now known to be distributed in the western Atlantic from Massachusetts (south of Boston) to Oregon Inlet, North Carolina. Living in the mid to upper rocky intertidal zone, it exploits a niche mostly unoccupied by native brachyurans. In the northern part of its range there is some mid-intertidal overlap with the green crab, Carcinus maenas. In North Carolina H. sanguineus becomes sympatric in the high intertidal with another grapsid, the wharf crab, Armases cinereum. Distributional evidence indicates that H. sanguineus was probably introduced via ballast water at one or more major shipping centres south of Cape Cod (i.e. the New York Bight, Delaware Bay, Chesapeake Bay), perhaps in the early 1980s. Its present latitudinal range in the western Atlantic is only about one-fifth of that in the western Pacific. H. sanguineus is now the most abundant brachyuran at the intertidal monitoring site in southern New Jersey, and apparently in some areas of Long Island Sound to the north. In New Jersey, crabs range in carapace width from 2.3 to 43.9 mm. The breeding season is from late April through September, and recruitment to the intertidal population begins in June and continues through the fall and winter. Some crabs become subtidal, particularly during the winter months, as evidenced by the growth of bryozoans, mussels and barnacles on their carapaces. There is no evidence in this population of parasitism with metacercariae, nemerteans, rhizocephalans or bopyrid and entoniscid isopods. ? 1998 International Council for the Exploration of the Sea
-
the western pacific brachyuran Hemigrapsus sanguineus grapsidae in its new habitat along the atlantic coast of the un11ed states reproduction
Journal of Crustacean Biology, 1998Co-Authors: John J McdermottAbstract:The Asiatic crab Hemigrapsus sanguineus, originally found as a single specimen in a rocky intertidal location in New Jersey in 1988, now has a geographical range in the western Atlantic from Massachusetts to North Carolina. In New Jersey, the crab reproduces from late April through September, and laboratory observations revealed that some crabs produce at least 2 broods in a season. Ovigerous females ranged from 12.1-35.8 mm in carapace width (CW), but relatively few females were sufficiently developed to reproduce at the lower end of this range. The abdominal width/CW ratio must be >0.60 for female crabs to be considered mature. Analysis of 300 females >12.0 mm CW revealed that crabs >17.0 mm are likely to be mature. The mean time required for embryo development to hatching of zoeae in the laboratory at 19-20?C was 22.3 ? 1.8 days (range 20-25 days; N = 8). Viable second broods produced in the laboratory did not require a second copulation. The number of embryos in broods of H. sanguineus was positively correlated with CW (N = 50), with some crabs ovipositing >40,000 eggs.
-
a breeding population of the western pacific crab Hemigrapsus sanguineus crustacea decapoda grapsidae established on the atlantic coast of north america
The Biological Bulletin, 1991Co-Authors: John J McdermottAbstract:The west Pacific grapsid crab Hemigrapsus sanguineus was found in the United States for the first time in 1988. Additional crabs were recovered in 1990 from Townsends Inlet and Cape May Harbor, New Jersey (22 males, 16 females), and four of the females collected from June through September were ovigerous. Thus, H. sanguineus has now established itself in southern New Jersey, the first well-documented case of an exotic brachyuran becoming established along the east coast of the United States.
Jeanclaude Dauvin - One of the best experts on this subject based on the ideXlab platform.
-
are mussel beds a favourable habitat for settlement of Hemigrapsus sanguineus de haan 1835
Aquatic Invasions, 2015Co-Authors: Jeanphilippe Pezy, Jeanclaude DauvinAbstract:Abstract Along the French coast of the English Channel, Hemigrapsus sanguineus (De Haan, 1835) is abundant under boulders on exposed shores that have high-energy hydrodynamic conditions in the intertidal zone. However, small individuals (< 6 mm) are rare in the muddy gravel sediments under boulders and the settlement habitat for post-larvae is largely unknown. This study explored whether mussel beds could represent a settlement zone for H. sanguineus . At the end of the summer of 2013, there were many post-larvae and small crabs in some mussel beds, with up to 528 individuals/m². However, at one location, no juveniles of H. sanguineus were found in mussel bed habitat despite the presence of adults on the same shore. We conclude that mussel beds are an important habitat for the settlement of juvenile crabs. Key words: Asian shore crabs, invasive marine species, English Channel Introduction The introduction of alien shore crabs into coastal environments is mainly the result of human activities that are becoming more frequent with the ever-increasing maritime traffic levels (Williams 1984; Ng et al. 2008). Nevertheless, the introduction of invasive species is a complex phenomenon, and there is a pressing need to assess the risks linked to biological invasions. In some cases, the introduced species can have a strong negative, or even a positive, effect on native species and/or communities (Carlton 1989; Ruiz et al. 1997; Cohen and Carlton 1998; Occhipinti-Ambrogi 2007). The Asian shore crab
-
biological traits explain the distribution and colonisation ability of the invasive shore crab Hemigrapsus takanoi
Estuarine Coastal and Shelf Science, 2014Co-Authors: Moâna Gothland, Jeanclaude Dauvin, Lionel Denis, F Dufosse, S JobertAbstract:Abstract Comprehending marine invasions requires a better knowledge of the biological traits of invasive species, and the future spread of invasive species may be predicted through comprehensive overviews of their distribution. This study thus presents the current distribution of a non-indigenous species, the Asian shore crab Hemigrapsus takanoi, as well as the species population characteristics (size distribution and cohorts), based on a five-year survey (2008–2012) along the French coast of the English Channel. Two large populations were found near harbours: one on the Opal Coast (where density reached 61 ± 22 ind.m−2, mean ± s.d., in Dunkirk harbour) and one on the Calvados coast (density up to 26 ± 6 ind.m−2, mean ± s.d, in Honfleur harbour). H. takanoi exhibited a short life cycle, a rapid growth, an early sexual maturity and a high adult mortality. These features, combined with previously described high fecundity and high dispersal ability, endow this species with an ‘r-selected strategy’. This strategy, which usually characterises species with a high colonisation ability, would explain the success of H. takanoi for colonising the French coast of the Channel. However, the species was found only in harbours and their vicinity; H. takanoi thus exhibited a discontinuous distribution along the 700 km of coastline. These results are discussed regarding sediment preference and potential introduction vectors. Hemigrapsus takanoi is now considered as established on the French coast and further studies are needed to evaluate the consequences of its introduction on the structure and functioning of the impacted shores.
-
Hemigrapsus sanguineus de haan 1835 crustacea brachyura grapsoidea a new invasive species in european waters the case of the french english channel coast 2008 2010
Aquatic Invasions, 2011Co-Authors: Jeanclaude Dauvin, Fabien DufosseAbstract:The unintentional introduction of the Asian shore crab, Hemigrapsus sanguineus, along the French coast during the mid 1990s has revealed the problematic effects that invasive species can have on biodiversity, entering into competition with native crab species. This invasion along coastal ecosystems of northern France has become an ineluctable, irreversible phenomenon. The present study describes the distribution and abundance of H. sanguineus along the French side of the English Channel from the Cotentin to the Opal Coast on the Dover Strait in spring and summer 2010. The results were compared with those obtained previously in 2008 and 2009 for the same areas and now show that the crab has increased in numbers since its first sighting in 1999. In 2010, the maximal abundance reached 51 ind.m -2 in Dunkirk harbour, and 69 ind.m -2 at La Hougue in the eastern part of the Cotentin Peninsula. Hemigrapsus sanguineus has been sighted all along the southern coastline of the English Channel to the North Sea (approximately 1,500 km). Its high colonisation potential suggests that this brachyuran could continue its invasion in European waters. Therefore a European surveillance network might be necessary to monitor its progression in the north-eastern Atlantic Ocean.
-
First record of Hemigrapsus takanoi (Crustacea: Decapoda: Grapsidae) on the western coast of northern Cotentin, Normandy, western English Channel
Marine Biodiversity Records, 2010Co-Authors: Jeanclaude Dauvin, J.b. DelhayAbstract:The sighting of the brush-clawed shore crab Hemigrapsus takanoi on the western coast of northern Cotentin confirms the extension of this species into the western part of the English Channel. This new sighting remains enigmatic because the Normanno-Breton Gulf circulation patterns do not appear to promote natural transport of crab larvae from the Atlantic or from the eastern part of the English Channel. It has been suggested that the professional oyster transport could be the origin of this species' presence on this part of the French coast.
-
asian shore crabs Hemigrapsus spp crustacea brachyura grapsoidea continue their invasion around the cotentin peninsula normandy france status of the Hemigrapsus population in 2009
Aquatic Invasions, 2009Co-Authors: Jeanclaude DauvinAbstract:This paper reports on the state of the Asian shore crab Hemigrapsus sanguineus (de Haan, 1835) population around the Cotentin Peninsula (Normandy, France) for 2009. As in 2008, the year of the first survey, the northern and eastern Cotentin coasts remain the most densely colonised. On the western shore, H. sanguineus remains rare, except in two sites not surveyed in 2008. In the east most colonised sites, Gatteville-Phare and La Hougue, the populations for both years indicate a rapid increase of abundance: maximum density > 50 .ind.m -2 in 2009 compared to 10 ind.m -2 in 2008. This observation probably demonstrates that the species' current significant increase is comparable to that of an invasive species. A second species of Asian shore crab Hemigrapsus takanoi Asakura & Watanabe, 2005 was only present on one eastern site off Saint-Vaast-La-Houge, but remains isolated.
Charles E Epifanio - One of the best experts on this subject based on the ideXlab platform.
-
abundance of invasive and native crab larvae in the mouth of delaware bay Hemigrapsus sanguineus and uca pugnax
Journal of Shellfish Research, 2013Co-Authors: Charles E Epifanio, Charles E Tilburg, Ana I DittelAbstract:ABSTRACT We compare larval distributions of the invasive Asian shore crab Hemigrapsus sanguineus and the native fiddler crab Ucapugnax. Our study was conducted in the coastal ocean adjacent to Delaware Bay on the east coast of the United States. Subtidal circulation in the study area is dominated by the Delaware Coastal Current, which is formed by the estuarine plume that extends southward out of the bay and along the inner continental shelf. The offshore edge of the current is marked by a strong density front and by convergent circulation along the frontal boundary. Surface plankton tows were taken at fine-scale intervals along saw-tooth transects traversing the front on 3 consecutive days in early August. Coincident physical measurements delivered hydrographic data throughout the investigation. Results provided a synoptic view of larval distribution near the bay mouth and showed patchy occurrence of the 2 species within the sampling area. Approximately 8.7 × 105 U. pugnax larvae were collected during th...
-
invasion biology of the asian shore crab Hemigrapsus sanguineus a review
Journal of Experimental Marine Biology and Ecology, 2013Co-Authors: Charles E EpifanioAbstract:Abstract The Asian shore crab, Hemigrapsus sanguineus, is native to coastal and estuarine habitat along the east coast of Asia. The species was first observed in North America near Delaware Bay (39°N, 75°W) in 1988, and a variety of evidence suggests initial introduction via ballast water early in that decade. The crab spread rapidly after its discovery, and breeding populations currently extend from North Carolina to Maine (35°–45°N). H. sanguineus is now the dominant crab in rocky intertidal habitat along much of the northeast coast of the USA and has displaced resident crab species throughout this region. The Asian shore crab also occurs on the Atlantic coast of Europe and was first reported from Le Havre, France (49°N, 0°E) in 1999. Invasive populations now extend along 1000 km of coastline from the Cotentin Peninsula in France to Lower Saxony in Germany (48°–53°N). Success of the Asian shore crab in alien habitats has been ascribed to factors such as high fecundity, superior competition for space and food, release from parasitism, and direct predation on co-occurring crab species. Laboratory and field observations indicate that H. sanguineus is a generalist predator with potential for substantial effects on sympatric populations of mollusks and crustaceans. However, broad ecosystem effects and actual economic impact are unclear. The literature on H. sanguineus is limited in comparison to better known invasive species like the European green crab (Carcinus maenas) and the Chinese mitten crab (Eriocheir sinensis). Nevertheless, there are substantial bodies of work on larval biology, trophic ecology, and interspecies competition. This paper presents a review of the biology and ecology of invasive populations of the Asian shore crab H. sanguineus in North American and European habitats.
-
three s a crowd space competition among three species of intertidal shore crabs in the genus Hemigrapsus
Journal of Experimental Marine Biology and Ecology, 2011Co-Authors: Mia K Steinberg, Charles E EpifanioAbstract:Hemigrapsus sanguineus is a small shore crab native to eastern Asia. In the past two decades, this species has established breeding populations on both sides of the North Atlantic. However, H. sanguineus has not become established in the eastern Pacific despite abundant shipping contact with Asian ports and suitable intertidal habitat. The experiments reported here investigate potential interactions between the invasive H. sanguineus and two congeners native to the west coast of the United States (H. oregonensis and H. nudus). Specifically, we tested interspecific competition for shelter at both the juvenile and adult life stages. We found that H. sanguineus adults have a strong preference for shelter and are unaffected by the presence of other species. However, juvenile H. sanguineus were out-competed for shelter, and this limitation may be preventing H. sanguineus from establishing a population in areas with high levels of early life-stage competition.
-
mating and sperm storage of the asian shore crab Hemigrapsus sanguineus
Journal of Shellfish Research, 2010Co-Authors: Julie A Anderson, Charles E EpifanioAbstract:ABSTRACT The Asian shore crab Hemigrapsus sanguineus is the principal invasive crab in many intcrtidal habitats on the east coast of the United States between Cape Hatteras and Maine. Previous work has described general aspects of mating for the genus Hemigrapsus; however, there has been no explicit study of mating behavior in H. sanguineus, and there has been little consideration of how this behavior might influence the success of H. sanguineus as a bio-invader. The objective of our investigation was to document the mating behavior of H. sanguineus under laboratory conditions and compare this pattern of behavior with that of other species of Hemigrapsus. Our observations show that mating in H. sanguineus was always initiated by the male and that both the male and female had calcified exoskeletons at the time of copulation. Small males were sometimes successful in securing mates, even in the presence of larger males. However, the male was larger than the female in 67% of the observed copulations. Duration...
-
characterization of the conspecific metamorphic cue for Hemigrapsus sanguineus de haan
Journal of Experimental Marine Biology and Ecology, 2010Co-Authors: Julie A Anderson, Marla M Valentine, Charles E EpifanioAbstract:Abstract The Asian shore crab, Hemigrapsus sanguineus, is one of the most abundant invasive crabs along the east coast of the United States. Larval stages are generally planktonic, but the megalopa stage settles to the substratum near the time of metamorphosis. Reducing the time to metamorphosis may result in higher recruitment and survival. Previous work has shown that a water-soluble cue produced by adult H. sanguineus can induce metamorphosis of conspecific megalopae. Here we report the results of experiments in which megalopae were exposed to cues produced by different life stages of H. sanguineus. We also provide data from experiments that investigated the temporal stability, detection threshold, and chemical classification of the cue. Our results indicate that an active cue is produced by juveniles as well as adults. The cue is proteinaceous and begins to degrade within 2 days of production. The threshold for detection of the cue by megalopae lies between 0.1 and 0.01 µg of protein per ml.
S Jobert - One of the best experts on this subject based on the ideXlab platform.
-
biological traits explain the distribution and colonisation ability of the invasive shore crab Hemigrapsus takanoi
Estuarine Coastal and Shelf Science, 2014Co-Authors: Moâna Gothland, Jeanclaude Dauvin, Lionel Denis, F Dufosse, S JobertAbstract:Abstract Comprehending marine invasions requires a better knowledge of the biological traits of invasive species, and the future spread of invasive species may be predicted through comprehensive overviews of their distribution. This study thus presents the current distribution of a non-indigenous species, the Asian shore crab Hemigrapsus takanoi, as well as the species population characteristics (size distribution and cohorts), based on a five-year survey (2008–2012) along the French coast of the English Channel. Two large populations were found near harbours: one on the Opal Coast (where density reached 61 ± 22 ind.m−2, mean ± s.d., in Dunkirk harbour) and one on the Calvados coast (density up to 26 ± 6 ind.m−2, mean ± s.d, in Honfleur harbour). H. takanoi exhibited a short life cycle, a rapid growth, an early sexual maturity and a high adult mortality. These features, combined with previously described high fecundity and high dispersal ability, endow this species with an ‘r-selected strategy’. This strategy, which usually characterises species with a high colonisation ability, would explain the success of H. takanoi for colonising the French coast of the Channel. However, the species was found only in harbours and their vicinity; H. takanoi thus exhibited a discontinuous distribution along the 700 km of coastline. These results are discussed regarding sediment preference and potential introduction vectors. Hemigrapsus takanoi is now considered as established on the French coast and further studies are needed to evaluate the consequences of its introduction on the structure and functioning of the impacted shores.
Nancy J Oconnor - One of the best experts on this subject based on the ideXlab platform.
-
changes in population sizes of Hemigrapsus sanguineus asian shore crab and resident crab species in southeastern new england 2010 2016
Northeastern Naturalist, 2018Co-Authors: Nancy J OconnorAbstract:The invasion of Hemigrapsus sanguineus (Asian Shore Crab) has been of concern in northeastern North America since the late 1980s. A relatively long-term record (1998–2011) of density estimates in southern New England showed displacement of resident crab species at 3 locations in Massachusetts and Rhode Island. In 2016, I visited the same locations to estimate current crab densities. The springtime Asian Shore Crab density decreased at a coastal location, but increased at an estuarine location to >300 crabs/m2. Resident crabs Carcinus maenas (European Green Crab) and Mud Crabs in the family Panopeidae increased in abundance at all 3 locations.
-
amphipods as potential prey of the asian shore crab Hemigrapsus sanguineus laboratory and field experiments
Journal of Experimental Marine Biology and Ecology, 2016Co-Authors: Johanna C Blasi, Nancy J OconnorAbstract:Abstract The invasive crab Hemigrapsus sanguineus has a generalist diet, consuming primarily macroalgae and sessile and sedentary invertebrate prey. To assess the dietary importance of motile prey, predation by H. sanguineus on the amphipod Hyale plumulosa was examined in laboratory and field experiments. Male and female crabs 7–27 mm in carapace width were offered H. plumulosa in laboratory microcosms with and without sediment (sand and rocks) present. Despite sex differences in claw morphology, male and female H. sanguineus consumed similar numbers of amphipods. Large crabs of both sexes consumed fewer H. plumulosa than small crabs, and consumption was lower when sediment was present. Crab abundance was then manipulated in the field in randomized complete block experiments in the lower rocky intertidal zone. In three 14-day experiments, H. sanguineus had no negative effect on amphipod abundance. In fact, excluding crabs from cages led to lower amphipod densities. The results of the 2-species predator–prey laboratory experiments did not transfer to the natural environment, suggesting that complex interactions exist between H. sanguineus and motile amphipod prey in rocky intertidal areas.
-
invasion dynamics on a temperate rocky shore from early invasion to establishment of a marine invader
Biological Invasions, 2014Co-Authors: Nancy J OconnorAbstract:Populations of invading Asian shore crabs (Hemigrapsus sanguineus) and resident crabs (European green crab Carcinus maenas or species in the family Panopeidae) were monitored for up to 12 years along a south to north orientation on the open coast of Massachusetts and within the Narragansett Bay estuary, Rhode Island. At all sites, densities of resident crabs declined as H. sanguineus increased in abundance. Population dynamics were divided into 3 stages of the invasion (early, mid, late) based on statistically different densities of invading and resident crabs. Early in the invasion on the open coast, the relatively few H. sanguineus present had a wide range of individual sizes. By late in the invasion, relatively small crabs [ 10 mm CW were present late in the invasion. In Narragansett Bay, a recruitment peak of H. sanguineus occurred shortly before it surged in population size, and large crabs were abundant late in the invasion. Geographic comparisons of H. sanguineus populations in southern New England showed similar growth trajectories. Monitoring populations of resident and invading species at multiple locations from early invasion through clear establishment of the invader allows a more complete understanding of the population dynamics of marine species invasions.
-
predation of the non native asian shore crab Hemigrapsus sanguineus by a native fish species the cunner tautogolabrus adspersus
Journal of Experimental Marine Biology and Ecology, 2013Co-Authors: Michael C Savaria, Nancy J OconnorAbstract:Abstract Predation of non-native species by native predators can impact the success of an invasion. Recently, the Asian shore crab, Hemigrapsus sanguineus , successfully invaded the northeastern coastline of the United States, reaching densities greater than 100 crabs·m − 2 in rocky intertidal areas. The goal of this study was to determine if a specialist fish predator of invertebrates, the cunner, Tautogolabrus adspersus , consumes the juvenile stage of H. sanguineus . In laboratory prey choice experiments, T. adspersus (10.2–22.1 cm total length) consumed greater numbers of native mud crabs (family Panopeidae, 3.0–9.0 mm carapace width) than H. sanguineus of similar sizes. T. adspersus also consumed more of the native blue mussel, Mytilus edulis , when paired with similar-sized H. sanguineus . Gut content analysis of 60 T. adspersus captured from intertidal zones with high populations of H. sanguineus in southeastern Massachusetts revealed low consumption of the invasive species; only 5 of 60 guts contained Asian shore crabs. Frequent prey items found in cunner guts included panopeid crabs, small snails, barnacles, and branching and encrusting bryozoans. Our results suggest that, as long as native prey species are present for consumption, T. adspersus will not exert high predation pressure on H. sanguineus .
-
predation by the nonindigenous asian shore crab Hemigrapsus sanguineus on macroalgae and molluscs
Northeastern Naturalist, 2003Co-Authors: Paul E Bourdeau, Nancy J OconnorAbstract:Abstract Prey selection and consumption of common molluscs and macroalgae by the Asian shore crab, Hemigrapsus sanguineus, were investigated in the laboratory. Crabs of three size classes (12–18, 19–25, 26–31 mm carapace width) collected from the rocky intertidal from May to November 1998, and were offered three mollusc species: the mussel Mytilus edulis, the clam Mercenaria mercenaria, and the snail Littorina littorea. Equal numbers of prey from three size classes or two species were offered concurrently to individual crabs. Crabs consumed small molluscs, large males opening larger molluscs than did females and smaller males. Male crabs consumed both mussels and clams. Females opened only mussels, but ate flesh from previously opened clams. Very few L. littorea were consumed. The macroalgae Codium fragile ssp. tomentosoides, Enteromorpha spp., Chondrus crispus, Fucus spp., and Ascophyllum nodossum were presented to individual crabs separately to determine consumption rates and together to ascertain speci...