How about some info about crabs? What kind do you use for bait for stripers? How do you fish them and whats some tips for looking for them?
Senior Member
How about some info about crabs? What kind do you use for bait for stripers? How do you fish them and whats some tips for looking for them?
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Crabology 101: All about crabs and bait
We've been talking about seeing crabs lately. Wanted to make sure the people running into them had a better understanding of what they're looking at, and the different distinctions.
I know guys who you would consider "crabologists". I'm not one, not enough knowledge yet.Some of these guys take collecting crabs down to a science. If you want to catch bass consistently with crabs in the summer, it takes some serious work, and the willingness to set up a crab tank, if ya wanna take it that far, for the bigger bass.
When the baitfish aren't around, resident bass gotta eat something. They're snacking on the crabs in and around the rocks. A little crunchy, but bass ain't that particular when they're searching for natural forage sometimes.
Anyone has anything to add in here, what you're using and how ya do it, feel free.
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Calico crabs: a little info
http://en.wikipedia.org/wiki/Lady_crab
The lady crab or calico crab, scientific name Ovalipes ocellatus, is a species of marine swimming crab.
Contents
[hide]
[edit] Distribution
- <LI class="toclevel-1 tocsection-1">1 Distribution <LI class="toclevel-1 tocsection-2">2 Habitat <LI class="toclevel-1 tocsection-3">3 Description <LI class="toclevel-1 tocsection-4">4 Life habits
- 5 See also
The lady crab is found in the Western Atlantic Ocean from Cape Cod to Texas.
[edit] Habitat
This species of crab is most often found in sandy substrates in quite shallow water, i.e. the surf zone. Normally, this is a very difficult habitat, because of strong wave action and constantly shifting sands. This animal escapes these dangers by burrowing just beneath the sand surface. As waves toss the sand around, the crab quickly shifts position and digs back under the surface.
[edit] Description
The claws of the lady crab are not particularly large, but they are sharp. The hind pair of legs are flat and paddle-shaped for swimming when necessary. The crab grows to be 4 in (10 cm) wide.
The carapace of this crab has projections known as "frontal teeth" between the eye sockets. The teeth behind the eyes are known as marginal teeth. The lady crab has three frontal teeth, and five marginal teeth on each side.
[edit] Life habits
The lady crab feeds on live or decaying marine organisms such as fish, crabs, or clams; this means it is both a predator and a scavenger. When fish or worms pass by, it comes out of the sand and grabs the animal with its claws.
Like other swimming crabs, the lady crab does not have a very thick or rigid carapace. This means it has less protection than some other crabs, which have harder shells or exoskeletons. Because it is not very well protected, it makes up for this by its speed and camouflage.
The lady crab has compound eyes at the tip of stalks, which allows it to be aware of predators.
[edit] Reproduction and growth
As is true of most crabs, males and females are distinguished by looking at the abdominal flap beneath their bodies. The female has a wide flap in order to carry the eggs, while the males have a thin flap. Once the eggs hatch, they are planktonic. The juvenile crabs do not resemble their parents until they have molted several times over the next few weeks. As they grow, they pass through two main stages called the zoea and megalopa before becoming an adult.
The lady crab molts as it grows, like most arthropods. These crabs appear to stop molting when they reach 4 in wide. Adults that have stopped molting are often covered in growths of barnacles or seaweed.
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Japanese shore crabs1: Invasive menace
These are good crabs to use as well, not as effective as the calicos, but still effective if you can get them when shedding. They are one of the most abundant species you will find, and it's said they will soon take over. So don't feel bad about using them, ya really can't deplete this resource.
Quick way to differentiate is they have bigger claws, but more rounded and less pointed, than the regular ones.
Japanese Shore Crab (Hemigrapsus sanguineus)
Photo credit: Copyright Koyou Crab Information, KoreaCredit: This web page was first developed by Jessica D. Sharon.
DESCRIPTION The Japanese shore crab’s identifiable features are a small hard bubble at the crux of its claws; three spines along each side of its shell (carapace), as opposed the similar-looking green crab which has five; and a light-and-dark banding pattern on its legs. The crabs grow to about the size of a silver dollar.
The crabs inhabit the rocky intertidal zone — between the high tide line and about one or two feet below low tide. They are omnivorous, eating macroalgae, salt marsh grass, and small invertebrates such as amphipods, gastropods, bivalves, barnacles and polychaetes. To the south, the crabs’ diet consists of mussels, clams, periwinkles and the European Green Crab (the latter two are also non-native species). The crab is able to reproduce several times a year. Whether the crab will have similar dietary preferences or be able to reproduce as frequently in Maine’s colder climate remains to be seen.
Size and Features: 2-3 inches, total width; carapace with three spines on each sidePhoto credit: Professor Larry Harris, University of New Hampshire
Habitat: Intertidal, rocky areas having cobble bottoms
Physical Appearance: Light and dark bands along its legs; red spots on its claws; and a body color ranging from pink to green to brown and even purple, depending on where it is found
Seasonal Appearance: Early spring to late fall
Behavior: Aggregate under rocks; not overly aggressive (Neils Hobbs, Department of Biological Sciences at the University of Rhode Island.)(Source: 1. Japanese Shore Crab, Department of Marine Resource, http://www.state.me.us/dmr/rm/asian_shore_crab.htm 2. Creature Feature: Japanese Shore Crab; The Bay's Uninvited Guest, by Mac Richardson, Save the Bay, http://www.savebay.org/aboutus/winte...re_feature.htm)
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Japanese shore crabs2: identification and habitats
Some interesting stuff
IMPACTSThe Japanese Shore Crab is slowly overtaking the habitat of native crabs, such as green crabs and mud crabs. This tiny invader is becoming more dominant while the numbers of resident crabs slowly decline. This is due, in part, because it is an opportunistic omnivore; essentially eating anything that it's offered.An omnivore with an appetite for young clams, scallops, oysters, algae, fish larvae, and many other species, these crabs may well pose a threat to New England ecosystems and aquaculture operations. This new competition in the food chain is leaving many other species struggling. Although the total impact of this species is not yet know, many are questioning whether or not there could be a link between the recent collapse of the lobster population in Long Island Sound, Maine. Others are concerned that perhaps there's a connection between the rise of the Japanese crab and the decline of the blue crab populations in the Chesapeake Bay.
(Source: 1. Tiny Invader Becomes a Bully in Local Waters, June 10, 2001, by John McQuiston, The New York Times http://www.seagrant.sunysb.edu/Media...-ANS061001.htm ; 2. A Quick Guide to Marine Bioinvaders, MIT Sea Grant College Program, http://web.mit.edu/seagrant/bioinvade/japcrab.html)Top
ORIGIN
Japanese Shore Crab was first identified on American shores in New Jersey in 1988. It's since made its way as far north as Portland, Maine, and as far south as North Carolina. The crab is indigenous to waters from southern Russia to Hong Kong The Japanese shore crab is invading Long Island Sound and crowding out native species, according to marine biologists. (Source: 1. Japanese Shore Crab, Department of Marine Resource, http://www.state.me.us/dmr/rm/asian_shore_crab.htm
DISTRIBUTIONLink to Nonindigenous Crustaceans in the United States Distribution Map (Florida Caribbean Science Center)
http://www.fcsc.usgs.gov/posters/Nonindigenous_Crustaceans/nonindigenous_crustaceans.html
Crustaceans
(Focus on the Great Lakes)
1999
U.S.Geological Survey, Biological Resources Division
Control Japanese Shore Crab
While there are not yet chemical and biological methods to control this species, there are many suggestions that can be followed in order to work towards eradication. Suggestions include establishing a database of current status of invasive species, monitoring changes in "residency" of existing invasive species populations, increasing public awareness, monitoring ballast water discharge from freighters, and sending posters and fact sheets to parks, beaches, or recreation areas.Each person plays an important role in preventing the introduction of non-native species, Here are some suggestions on how you can help:.
(Source: 1. Three new Exotic Species of the Chesapeake and Coastal Regions, Maryland Recreational Fisheries,
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"White leggers" or blackfish crabs
This comes to us courtesy of Scott's B&T, THE tackle place to visit when you fish the Mystic Island NJ area.
www.scottsbt.com/misc/crabbing/baitcrabs.htm
Info on Whiteleggers
This is a tough one...when you look up whiteleggers online you get all kinds of conversations about what crabs they are..but nothing concrete. I think that many folks have tagged multiple crabs with this nickname...listing them below. They are apparently very tasty to the Tautog...if you can find any local sources for them.
Atlantic Rock Crab
Fly lure w/crab info
Rock Crab info
Calico (Lady) Crab
http://en.wikipedia.org/
Jonah Crab
http://en.wikipedia.org/
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Fiddler and green crabs
This also comes from Scott's B&T. Stop by and check out all the seasonal deals they have, and the freshest bait.
Here's a link to Scott's main page with store hours and location info:
http://www.scottsbt.com/
They also have a sister site, Mystic Island.com
www.mysticisland.com
www.scottsbt.com/misc/crabbing/baitcrabs.htm
Fiddler
Crabs
Unlike green crabs, these are harvested in warm gulf climates. Fiddler crabs are sold by quantiy, not pounds: pint, quart, 1/8 bushel. Fiddler crabs are not nearly as hearty as green crabs. They are best kept cool/damp in the refrigerator (not wet, they'll rot). They can be kept in the lagoon in a box, but not as well as other crabs.
Most stores stock fiddlers from May - September (we don't have them here). Fiddler crabs are a favorite for those people fishing inshore, on jetty's or along bulkheads and sodbanks. Fiddlers can also catch fluke and weakfish. They work very well on wrecks for sea bass and blackfish, but all the junk fish also like them. You only get one bite, and you either caught the fish or you need new bait. They are not very useful on a wreck with a lot of bergalls or 3-4 inch sea bass. too much time is spend going from boat to bottom and back up again. Fiddler crabs are a good choice for some inshore fishermen, especially where there is a smaller size of fish. They can be caught locally, but as this is incredibly time consuming, we usually order them in as well.
Fiddlers are generally used with much smaller tackle, possibly #1 or #2 hooks on the rigs. Larger hooks tend to break the crabs, which are generally only 3/4 - 1 inch long and very delicate.
**********************
The Green Crab by Russell & Maureen Albertson
Green Crabs are used to catch a variety of different fish, but most often are used to catch Tautog(alias blackfish,slippery bass). Black Sea Bass, Ling and Codfish can also be caught on crabs while fishing on wrecks and artificial reefs. Stripers have been caught on green crabs in the fall, although they are not commonly used as a striper bait.
It is interesting to note that many good catches of weakfish were made possible by using shedder green crabs. OH!--Did you forget they shed, also?. Well, they do, although they are much harder to identify as shedders, because the same symptoms that are visible on a blue claw crab are hidden by the green crab's darker colors.
Green crabs, like the bloodworms, are most often imported from the New England states. They are indigenous to our area, but with the extreme tides in the northern states the green crabs are much easier to trap. When fishing Tautog, any live crab cut properly will work. Spotted ocean crabs, sand fleas, calico crabs and fiddler crabs are part of a tautog's normal diet. Green crabs are purchased by the fisherman who doesn't want to spend any of his valuble fishing time catching bait, and are available almost year-round in our store. The exception being during January - February, when they sometimes become scarce. The weather gets so cold in Maine, that the harvesting of the crabs kills them before they can be stored at temperatures above freezing.
Uses and tips for fishing with Green crabs
Green crabs are used in various ways. Techniques differ depending on the individual who is doing the fishing. A crab that is put on as bait whole and intact will assure that the larger of the fish in any one school will be on your line. Big bait catches big fish.{pounding fist!}However, there is one drawback to this theory.
If the fishing is slow, the water cold, or the tautog are being picky, the other fishermen on the boat will catch more fish with crabs that they have dressed up. This can be achieved by doing any one or all of the following:Green crabs are usually bought by the dozen. One dozen crabs normally means 2 dozen baits. Crabs can also be purchased in bulk: 1/8 bushel, 1/4 bushel, 1/2 bushel, full bushel. Charter boats purchase several bushels of crabs at a time. During a real good fishing trip, two people could use up 1/4 bushel of crabs. However, an 1/8 bushel of crabs will catch all the fish that any two people care to spend hours cleaning.
- Cutting them in half
- Removing the claws
- Peeling off the back shells
- Removing the swim fins.
If you have extra green crabs after fishing they can be stored in a refrigerator for up to two weeks. It is recommended to put green crabs in a spare refrigerator that's just for bait, because they stink. Green crabs can also be stored in a bait box in salt water that has good circulation. When the water warms up, sinking the bait box to a cooler water depth will assure a better survival ratio.
Feeding them is only necessary if you are trying to hold them for long periods of time. Green crabs are ravenous and they will consume any fish carcass. Try not to expose green crabs to long periods of sun or heat, they will die.
All Green crabs smell somewhat. DO NOT attempt to use dead smelly rotten green crabs. If the bad scent gets on your cutting board, it will ruin all the good crabs you cut next. So make sure the crabs are moving, even if it is ever so slightly! Yes, this means that freezing your left-over green crabs is not a good idea.
Rigs are basically a top/bottom style with two bait holder hooks. Anything labeled sea bass, blackfish or tautog. Use enough weight to hold bottom.
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Blue claw crabs: Baseball, apple pie, and blueclaws
Everyone's favorite, but I believe there are size limits when using them for bait, so be sure to follow the regs. Blueclaws are mostly targeted for eating, not using for bait, because in our areas they can reach the largest size.
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Spider crabs: bait stealers and line tanglers
Yup, that's what they do, not much good for anything else, or are they?
http://en.wikipedia.org/wiki/Spider_crab
The term spider crab can refer to crab various species of crab in the family Majidae. See Crab spider for spiders of the Thomisidae family.
- Japanese spider crab (Macrocheira kaempferi), the largest crab alive, found on the bottom of the Pacific Ocean
- Portly spider crab (Libinia emarginata), a species of crab found in estuarine habitats on the east coast of North America
- Hyas, a genus of spider crabs, including the great spider crab (Hyas araneus), found in the Atlantic and the North Sea
- Maja squinado, sometimes called the "European spider crab"
Portly Spider Crabs:
Portly spider crabScientific classificationKingdom:Animalia
Phylum:Arthropoda
Subphylum:Crustacea
Class:Malacostraca
Order:Decapoda
Suborder:Pleocyemata
Infraorder:Brachyura
Family:Majidae
Genus:Libinia
Species:L. emarginata
Binomial nameLibinia emarginata
Leach, 1815
The portly spider crab, Libinia emarginata, is a species of crab found in estuarine habitats on the east coast of North America from Nova Scotia to the Gulf of Mexico. This crab grows to about 10 cm (4 inches) across its back, which is spiny and often covered with a "garden" of sponge and seaweed. The carapace is shiny, covered with short hairs, and its color varies from brown to a dull yellow; the tips of the claws are white. The hairs on the shell attract algae, barnacles, and debris. It likes to camouflage after moulting. The portly spider crab is very slow moving, and is a scavenger.
The portly spider crab is generally not considered edible, unlike the blue crab which is often found in the same waters.
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Sand crabs and mole crabs: What's in a name?
They are often mis-labeled, or labeled different things in different regions. In some southern states, people call them sand fleas. In the NY bight area, whe have real sand fleas which look nothing like these crabs, and the sand fleas will bite.
If ya think those small white sand fleas are harmless, try falling asleep on the beach at night, or leave a bag of bait on the sand for an hour, and watch what happens.
http://en.wikipedia.org/wiki/Mole_crab
Hippoidea is a superfamily of decapod crustaceans known as sand crabs or mole crabs [1].
[edit] Ecology
Hippoids are adapted to burrowing into sandy beaches, a habit they share with raninid crabs, and the parallel evolution of the two groups is striking [2]. The whole body is almost ovoid, the first pereiopods have no claws, and the telson is long, none of which are seen in related groups [3]. Unlike most other decapods, sand crabs cannot walk; instead, they use their legs to dig into the sand [4]. Members of the family Hippidae beat their uropods to swim [4].
Apart from the polar regions, hippoids can be found on beaches throughout the world. Larvae of one species have also been found in Antarctic waters, despite the lack of suitable sandy beaches in the Antarctic [5].
[edit] Classification
Alongside hermit crabs and allies (Paguroidea), squat lobsters and allies (Galatheoidea) and the hairy stone crab (Lomis hirta, Lomisoidea), Hippoidea is one of the four groups that make up the infraorder Anomura [6]. Of the four, Hippoidea is thought to be the most basal, with the other three groups being more closely related to each other than to Hippoidea [7].
The fossil record of sand crabs is sparse [8], but extends back to the Cretaceous period [2]. Sand crabs are placed in three families († represents exclusively fossil taxa [9]):
Senior Member
blueclaw crabs
Hey Dark I found a cool site about blueclaws.
Blue Crab Identification
Claw Color
Here's an easy way to tell the difference between a male and female blue crab. Males have blue claws, and, like most humans, female blue crabs "paint their fingernails" (i.e., the tips of their claws are "painted" red!)
Abdomen
In addition to the claws, there are other (better) ways to determine the gender of a blue crab. But first, a little science.
The Atlantic blue crab (Callinectes sapidus) is a member of the Brachyura - an order of crustaceans having a reduced abdomen, or "apron," folded against the ventral surface (or belly) of the animal. An easy way to think about this concept is to make a crab out of a lobster. You take a lobster, shorten up its tail and fold it up under its body between the legs, then press the tail up into its bottom shell until it's flush. VoilÃ*! You now have a crab... well, sort of! This should help illustrate how a crab evolved to its current form.
As you will see in the following images, the male and female crab have entirely different shaped aprons which makes determining gender very easy. And, the apron is yet again very different for adolescent and adult females making it easy to determine the female's sexual maturity (determining the male's maturity is a bit trickier.)
Sexual Maturity
"Jimmy"
A male blue crab, known as a "Jimmy" to watermen, has a long, narrow, inverted "T" shaped apron and blue-tipped claws.
Unlike female blue crabs, there is no easy way to distinguish the sexual maturity of the male. However, upon close inspection, you will note that the apron of the adolescent male is tightly sealed to his body whereas the adult male is free to open his apron (like the mature female, the male opens his apron in order to mate.) The adult male has locking spines adjacent to the fifth thoracic segment which hold his apron shut.
"Sally"
A immature (adolescent) female blue crab, known as a "Sally" or "She-Crab" to watermen, is easily identified as having an inverted "V" or triangular shaped apron and red-tipped claws. Her apron is tightly sealed to her body and does not open since she cannot mate or carry eggs.
"Sook"
A mature (adult) female blue crab, known as a "Sook" to watermen, is identified as having an inverted "U" or bell-shaped apron and red-tipped claws. Her broadly rounded abdomen is free to open and is not sealed shut as before. She must open her apron in order to mate and to carry eggs (see "Sponge Crab.")
Egg-Bearing Female Blue Crab
"Sponge Crab"
"Pregnant" female blue crabs carry fertilized eggs under their abdomen. From a distance these eggs resemble a sponge, hence the term "sponge" crab. It takes about two weeks for the eggs to "ripen" and be released into the water to hatch. It is illegal in many states to possess sponge crabs.
Please note that there is a lot of misinformation being circulated about the female blue crab and whether she has ever released eggs. Some people wrongly believe that sooks taken from the brackish waters of the mid to upper Chesapeake Bay have released eggs (spawned) and are therefore fair game. This is probably not true. When the female is about to become sexually mature, she molts and then mates with a male. During this mating, the male's sperm is transferred to special sacs inside the female for use at a later time... much later! Here's where we clear up the confusion: Mated, Yes. Spawned, No. There's a big difference between the two! After mating, and toward the end of the season, the "impregnated" sooks will migrate south toward the mouth of the Chesapeake Bay. It is here, in the high-salinity waters of the extreme lower Chesapeake Bay and Atlantic ocean, where she actually fertilizes her eggs and spawns.
What does this mean in plain English? It means that the bulk of the sooks taken from Maryland and Virginia waters are females that have probably never released any eggs. Think about this fact the next time you take a sook from these waters.
Please see Mating and Spawning for more detailed information.
http://www.bluecrab.info/identification.html
Life cycle of blueclaw crabs - according to this female blue claws can live 5 to 8 years.
http://www.bayjournal.com/article.cfm?article=1845
Senior Member
blueclaw crab life cycle
I spent like an hour on this site, really cool info. This is about the life cycle.
http://www.bluecrab.info/lifecycle.html
Senior Member
yur right that is a cool site thanks for posting it up dude
Senior Member
Crabs are in abundance this year. A friend of mine got one over the weekend that measured about 8", big crab.
Senior Member
I think this will be a good year for them too, though a lot of them are still small yet. I don't fish for bass with shedders regularly. Friends that do, can catch bass throughout the summer. It is too much work for me.
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I told Vpass I would hunt for this thread. This is for you, bro....
Senior Member
Cool, Thanks Dark. I will look thru the posted info. and see if I could add anything to this topic.Originally Posted by DarkSkies
I told Vpass I would hunt for this thread. This is for you, bro.
Senior Member
Some Biological, and Commerical information on Rock Crabs, and Jonah Crabs
Cancer irroratus reproduction occurs in the autumn. Sexual maturity in females is attained once they reach the CW size of 60 mm. Males have a slightly larger size of CW 70 mm at sexual maturity. Before mating commences, both male and female rock crabs moult their shell. This event for males happens during the winter months to ensure that their shells are completely firm before the fall. Females moult their shells during the fall so that they remain soft during mating. It takes rock crab shells between 2-3 months to fully harden. After fertilization females lay their eggs and store them under their stomach for almost a year. Depending upon the female's size the number of eggs produced can range from 125,000 to 500,000. After this period of time the eggs hatch and between the months of June to September the larva stay in the water column. By the time autumn returns the larva that were hatched metamorphose into extremely small crabs called megalops. For the first part of their life these young crabs are extremely vulnerable to predators and water turbulance. To increase their chance for survival they remain in shallow water and at the bottom of the ocean floor for protection (Gendron,2001).
The above was taken from the link below:
http://animaldiversity.ummz.umich.ed...irroratus.html
More info:
http://www.dfo-mpo.gc.ca/Library/326113.pdf
Senior Member
Re: Japanese shore crabs2: identification and habitats
Dark, outstanding job on the research and teaching you have done in this thread.
I have been raking crabs for the last 2 months. Fish to 24 pounds. Last night got one that was 13.
You can also use the Asian shore crabs (you refer to them as the Japanese shore crabs) as well. What it seems to me is the calicos and whiteleggers are better. The Asians work but as they are smaller you tend to get skates and other small nuisance fish like sea robins. If I am going to the trouble to rake crabs I certainly don't want to feed them to skates.
But, just for you fellas to know that the Asians will work in a pinch. They do have to be shedding though or it will not work.
Here is some more info I found on the Asians.
http://fl.biology.usgs.gov/Nonindige...hore_crab.html
Printable PDF Format
NONINDIGENOUS SPECIES INFORMATION BULLETIN
Asian shore crab, Japanese shore crab, Pacific crab,
Hemigrapsus sanguineus (De Haan)
(Arthropoda: Grapsidae)IDENTIFICATION: The Asian shore crab has a square-shaped shell with 3 spines on each side of the carapace. The carapace color ranges from green to purple to orange-brown to red. It has light and dark bands along its legs and red spots on its claws. Male crabs have a distinctive fleshy, bulb-like structure at the base of the moveable finger on the claws. This species is small with adults ranging from 35 mm (1.5 in) to 42 mm (1.65 in) in carapace width. NATIVE RANGE: Hemigrapsus sanguineus is indigenous to the western Pacific Ocean from Russia, along the Korean and Chinese coasts to Hong Kong, and the Japanese archipelago.LIFE HISTORY: This species is an opportunistic omnivore, feeding on macroalgae, salt marsh grass, larval and juvenile fish, and small invertebrates such as amphipods, gastropods, bivalves, barnacles, and polychaetes. The Asian shore crab is highly reproductive with a breeding season from May to September, twice the length of native crabs. The females are capable of producing 50,000 eggs per clutch with 3-4 clutches per breeding season. The larvae are suspended in the water for approximately one month before developing into juvenile crabs. Because of this, the larvae have the ability to be transported over great distances, a possible means of new introductions.
(Specimen courtesy of Susan Park, University of Delaware)
HABITAT: This versatile crab inhabits any shallow hard-bottom intertidal or sometimes subtidal habitat. They can live on artificial structures and on mussel beds and oyster reefs. They also tend to aggregate at high densities under rocks where they overlap habitats with native crab species. Hemigrapsus can tolerate wide ranges of salinity and temperature as well as damp conditions in the upper intertidal regions.
NONINDIGENOUS OCCURRENCES: Hemigrapsus was first recorded in the United States at Townsend Inlet, Cape May County, New Jersey in 1988. This species is now well established and exceptionally abundant along the Atlantic intertidal coastline of the United States from Maine to North Carolina. It is actively breeding and expanding its population within its nonnative range. Because the species is tolerant of a wide range of environmental conditions, it is likely that the invasion will continue along the US coastline.
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.
IMPACTS: 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. It also occupies habitats very similar to our native mud crabs, possibly overwhelming and dominating their habitat. This potential impact on native species populations may be a result of direct predation or competition for a food source. Hemigrapsus may compete with larger species, like the blue crab, rock crab, lobster, and the nonnative green crab. Recent trends show numbers of shore crabs are steadily increasing while native crab populations are declining. These opportunistic omnivores may also pose threats to coastline ecosystems and aquaculture operations. There are still many questions to be answered by scientists about impacts this species may pose to biodiversity in those ecosystems affected.
CONTROL AND MANAGEMENT: 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. Scientists are monitoring changes in native species, tracking the shore crab's spread along the coastline, and conducting experiments to increase their knowledge of basic biology and ecology of this species. Ballast water management is also being researched to reduce or eradicate new introductions from occurring.Printable PDF FormatPhoto GalleryIf you have collected or observed this species, or know of someone who has, please call the Nonindigenous Aquatic Species Toll-Free Hotline, 1-877-STOP-ANS and report the information. Or, report it to http://nas.er.usgs.gov/SightingReport.asp or,Amy Benson amy_benson@usgs.gov
Senior Member
Re: Japanese shore crabs2: identification and habitats
Dark Skies I have to tell you I thoroughly enjoy the threads you create. I can tell a lot of painstaking research goes into them. Whether it is information about the moratorium and declining bass numbers or guidelines and suggestions about fishing, you really try to pass along your knowledge. At one time I had the energy you had but now I am enjoying my golden years. Thank you for trying especially to educate the younger anglers out there. Bucket head I used to rake crabs a long time ago. They are without a doubt the best offering you can use to entice bass for the hot summer weather. It is tedious and time consuming and I can assure you that Bucket head earns every bass he catches. Too much work for me at this stage but I enjoy your stories. Good luck gentlemen.
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