CRAB

CR 1/1

LUO, Y. and S. WEI
A study on the experimental ecology of the mud crab Scylla serrata (Forskal).
1896   5 p
Donghai Mar. Sci./ Donghai Haiyang, vol. 4, no. 3, 91–95

A study of the experimental ecology of the mud crab S. serrata was made. The juveniles and adults of the mud crab were fed for two years in the laboratory. They mainly feed on the Mollusca, and also a few of the fish, shrimp and algae. Their suitable water temperature is 18–30 degree c: they rest at 12–14 degree C, and die at temperatures lower than 11 degree C. The juveniles moult frequently and grow rapidly with the rise of the water temperature within the suitable temperature range. They reach sexual maturity in one year, during which they moult 14 times and have 15 instar stages. As they are often eaten by other individuals of the same species during moulting, suitable shelters are necessary in the pool, and the suitable amount per square meter is 10–15 for juveniles or 5–7 for adults. According to the natural ecological environment which the mud crab lives, the females can be fertilized and lay eggs regularly in openair conditions.

CR 1/2

MANTHE, D.P., MALONE, R. and H. PERRY
Factors affecting molting success of the blue crab Callinectes sapidus Rathbu held in closed, recirculating seawater systems.
1985   2 pp
J. Shellfish Res., vol. 5, no. 1, 40–41

A commercial, closed, recirculating seawater facility that utilized biological filters for control of nitrogenous metabolites is described. Loading rates of 1,000 crabs (Callinectes sapidus) were maintained in each system. Parameters (NH sub(3)-N, NO sub(2)-N, No sub(3)-N, pH, dissolved O sub(2), salinity, temperature, alkalinity) that affect molting survival and commercial operating procedures that affect water quality were monitored for a 2-month period and are presented. Alkalinity and pH values declined in the systems, demonstrating a limited buffering capacity of the filter. Values that exceeded 350 mg/L NO sub(3)-N were observed with no apparent effects to the crabs. Increased multiple mortality occurred when concentrations of nitrite that approached 1.6 mg/L NO sub(2)-N accumulated in the systems. Nitrite accumulations were associated with depressed oxygen levels that were induced by peak system loading or equipment failure. Molting rates in excess of 95% were observed and in general, acceptable water quality was maintained by the filters.

CR 1/3

MALONE, R.F. and D.P. MANTHE
Interim design recommendations for closed-recirculating blue crab shedding systems.
1984   13 pp
Lousiana State Univ., Dep. Civil Engineering

Design and management criteria of closed-recycling soft shell shedding system are summarized.

CR 1/4

MOTOH, H., PENA, D., DIMAANA, M. and E.Q. TAMPOS
Preliminary report on the first production of the crab stages of alimasag, Portunus pelagicus (Linnaeus).
1978   6 pp
Q. Res. Rep. Aquacult. Dep. SEAFDEC, vol. 2, no. 3, 16–21

An experiment was undertaken studying the early life history of Portunus pelagicus in order to obtain information of relevance to rearing techniques for crabs.

CR 1/5

MARICHAMY, R. and S. RAJAPACKIAM
Culture of larvae of Scylla serrata.
1984   3 pp
Mar. Fish. Inf. Serv. Tech. Ext. Ser., no. 58, 13–15

A description is given of a system for the mass rearing of mud crab (Scylla serrata) in coastal ponds in Tuticorin Bay.

CR 1/6

COWAN, L.
Crab farming in Japan, Taiwan and the Philippines.
1984   85 pp
Inf. Ser. Dep. Primary Ind. (Queensl.), no. Q184009, 85 pp

The report covers crab culture of Portunus trituberculatus and Scylla serrata in 3 different countries which show different developmental directions. In Japan, modern technology is utilized to mass produce millions of juveniles for fisheries re-stocking; in Taiwan, the crab farming industry is differentiated into nursery, grow-out and fattening operations and commercial hatcheries are being developed. Finally in the Philippines, wild caught crabs are reared at low density in intertidal ponds as a minor crop with prawns or milkfish.

CR 1/7

ODA, T.
Rearing experiments of the larval blue crab Portunus trituberculatus with the artificial diets. 1. On the effective feeding rate of the artificial diet for the zoea larvae.
1984   5 pp
Bull. Fish. Exp. Stn. Okayama Prefect. 88–92

In Japanese language

CR 1/8

ODA, T.
Rearing experiments of the larval blue crab Portunus trituberculatus with the artificial diets. 2. On the effects of artificial diets supplemented with chitin.
1984 4 pp
Bull. Fish. Exp. Stn. Okayama Prefect., 1984, 93–96

In Japanese language

CR 1/9

ODA, T. and M. MURATA
Mass production of seedlings of blue crab Portunus trituberculatus.
1984   3 pp
Bull. Fish. Exp. Stn. Okayama Prefect., 1984, 172–174

In Japanese language

CR 1/10

MANTHE, D.P., MALONE, R.F. and H.M. PERRY
Water quality fluctuations in response to variable loading in a commercial, closed shedding facility for blue crabs.
1983   8 pp
J. Shellfish Res., vol. 3, no. 2, 175–182

A commercial, closed recirculating seawater facility using biological filters for control of nitrogenous metabolites is described. The volume of each system was 7,560 l. Loading densities of over 1,000 crabs (Callinectes sapidus Rathbun) were maintained in each system. Water quality parameters (NH sub(3)-N NO sub(2)-N, NO sub(3)-N, pH, dissolved oxygen, salinity, temperature, alkalinity) affecting crab survival at moulting were monitored for a 2-month period, and safe operational ranges were established. Alkalinity and pH value declined in the systems, demonstrating a limited buffering capacity. Values of NO sub(3)-N exceeding 350 mg/l were observed with no apparent effects to the crabs. Increased molting mortality was observed when concentrations of nitrite approached 1.6 mg/l NO sub(2)-n. Nitrite accumulations were associated with depressed oxygen levels which were induced by peak system loadings or equipment failure. Successful molting rates in excess of 95% were achieved at nitrite an ammonia concentrations below 1 mg/l.

CR 1/11

KANAZAWA, A., RESHIMA, S., KOBAYASHI, T., IWASHITA, T. and M. KAWASAKI
Rearing of the larval crab, Portunus trituberculatus, with the artificial microparticulate diets.
1983   7 pp
Mem. Fac. Fish. Kagoshima Univ., 1983, vol.32, 121–127

Attempts were made to rear the larval crab, Portunus trituberculatus, with the artificial microparticulate diets, nylon-protein microencapsulated diet (MED) gelatinarabic gum-MED, cholesterol-lecithin micro-coated diet (MCD), and carrageenan microbound diet (MBD). In the first experiment, the feeding rate the rotifers in the practical seed production of the crab was reduced by half and replaced with one of the above artificial diets during the period of zoea sub(20-zoea sub(4) stages. The larval crabs receiving every artificial diet along with the rotifers in the above mentioned manner had an 11–20% survival comparable to the survival rate of the control group receiving the live feeds such as the rotifer, Artemia) nauplii, and the minced meat of a short-necked clam. In the second experiment, the larval crab was reared with one of the artificial diets alone after hatching. Every artificial diet sustained growth of the larval crab from zoea sub (1) to juvenile stages, although the survival rates of the crab receiving the artificial diets were lower than that of the crab receiving the live feeds (control group). The results of the present study show that rearing the larval crab with the artificial microparticulate diets is successful.

CR 1/12

PERRY, H.M. and R. WALLACE
Blue crab shedding systems: water quality concerns.
1985   6 pp
Mississippi-Alabama Sea Grant Consort., Ocean Springs, 1985, 6 pp.

The operation of a successful, closed recirculating seawater system depends on the maintenance of acceptable water quality. Water in closed systems is altered by the excretion of waste products (metabolites) from the crabs and from the introduction of foreign substances into the system (contaminants). Water quality parameters affecting shedding success include dissolved oxygen, temperature, salinity, pH, ammonia and nitrite. This paper discusses the importance of these parameters, their influences, measuring methods, and management guidelines.

CR 1/13

SAKAI, T., TOMIYAMA, T. and T. HIBIYA
Fisheries in Japan: Crab.
1983   178 pp
Japan Marine Products Photo Materials Assoc., Tokyo, 1983, 178 pp

This volume deals with the crabs of Japan. Information covers taxonomy, reproduction, distribution, ecology, fishery, seed production and consumption. Each species is illustrated by a color photograph as are all other sections on the book.

CR 1/14

SUN, Y.M., YAN, Y. and J.J. SUN
The larval development of Portunus trituberculatus.
1984   8 pp
J. Fish. China, vol. 8, no. 3, 219–226

Observations on the larval development of Portunus trituberculatus under artificial cultivation are presented. Based on the morphological characteristics, the process of metamorphosis may be divided into five stages, four zoeal stages and one megalopa stage. The number of the feathery setae on the distal portion of the exopodites of the 1st and 2nd maxillped, the form of the pleopods and the number of the setae on the caudal concavity may be used the main features for distinguishing the different zoeal stages. Development from the 1st zoeal stage to the young crab required 15–18 days (the zoeal stage required 10–12 days and the megalopa stage required 5–6 days) at a temperature of 22–25 degree C, under artificial cultivation.

CR 1/15

NAKANISHI, T. and M. NARYU
Some aspects of large-scale rearing of larvae and post-larvae of the king crab (Paralithodes camtschatica).
1981   8 pp
Bull. Jap. Sea Reg. Fish. Res. Lab., no. 32, 39–47

Large-scale rearing of larvae and post-larvae of the king crab was studied in 30 1 and 500 1 tanks. When the water temperature was maintained under 3 degree C, egg-bearing females reared for one year and could hatch out larvae normally. The best survival ratio at the first stage young crab was 38.8% in 30 l tank and 16.62% in 500 l tank. There was a lot of cannibalism even at the larval stage.

CR 1/16

NAKANISHI, T.
The effects of temperature on the growth, survival and oxygen consumption of larvae and post-larvae of Paralithodes brevipes (Decapods: Anomura).
1981   7 pp
Bull. Jap. Sea Reg. Fish. Res. Lab., no 32, 49–56

In order to study the effects to temperature on larvae and post-larvae of P. brevipes 2 types of experiments, growth test under controlled laboratory conditions and metabolic rate, were designed. With the growth test, -1.8 degree, 3 degree, 8 degree, 13 degree and 18 degree C were used as the experiment temperature. The growth rate was similar at 8 degree, 13 degree and 18 degree C. At 3 degree C, the rate was twice that at 8 degree, 13 degree and 18 degree C. At -1.8 degree C, larvae did not develope to Z2. The survival ratio at Z3 was 30–50% at 8 degree C, and this was the highest ratio in this experiment. Temperature had less influence on the oxygen consumption at Z1 and G than that at Z2 and Z3.

CR 1/17

ODA, T. and Y. BAMBA
Mass production od seedlings of blue crab Portunus trituberculatus.
1982   3 pp
Bull. Fish. Exp. Stn. Okayawa Prefect., vol 1981, 227–229

In Japanese language

CR 1/18

PAUL, M.R. and J. AZARIAH
Laboratory larval culture. A keystone in marine biotechnology.
1982   93 pp
Atlantica, vol. 5, no. 2, 93 p

A detailed study on the culture aspects of the estuarine crab Sesarma quadratum has been carried out. The present paper identifies two basic problems which seem critical for enhanced larval survival: 1) the suitability of food item and 2) the absence of security from ciliate predation. The unsuitability of fresh hatched nauplii of Artemia salina as larval diet has been pointed out. Maintaining the crab larvae on diet of axenic monocultures of seven species of algae and diatoms proved successful with 100% survival for a period of 6-1 days; but the zoea I never moulted to zoea II; they continued as zoea I till they died. In lieu of the fertilized eggs of sea-urchins the early developing embryos of the serpulid Hydroides elegans were used as larval diet.

CR 1/19

NAGABHUSHANAM, R., SAROJINI, R. and U.M. FAROOQUI
Prospects of the mud crab (Scylla serrata) culture in India.
1982   83 pp
Atlantica, vol. 5, no. 2, 83 p

The mud crabs, S. serrata, is commercially the most valuable in India, with great potential for large scale culture operations. The present paper deals with the results obtained in the experimental culture of Scylla in different types of cages in the shallow waters. The seeds were collected from intertidal flats. The young crabs were first reared in basket type cages made of cane for 3 months. Box type cages made of wooden planks, each having 10 compartments, were preferred for culturing the adult crabs. The crabs were fed with trash fish and clam meat. The growth rate of the crabs appeared to be good, as a number of animals moulted at the interval of 20–40 days. They reached marketable size through 5 to 6 moults in about 10 months.

CR 1/20

BOOKHOUT, C.G. and J.D. Jr. COSTLOW
Methods for rearing crabs in laboratory.
1981   17 pp
Marine Invertebrates. Laboratory Animal Management.
National Academy Press, Washington, DC (Usa), 250–267

A brief outline is given of the life history of Brachyura and methods of rearing crabs in the laboratory are described. Relevant information concerning the equipment to be used is also presented.