ECOLOGY OF CALLINECTESARCUATUS AND C. BELLICOSUS (DECAPODA, PORTUNIDAE) IN A COASTAL LAGOON OF NORTHWEST

MEXICO

JOSÉ A. ARREOLA-LIZ.~RAGA LUIS G. HE&NDEZMORENO SERGIO HERNANDEZ-V~QUEZ~~), FRANCISCO J. FLORES- VERDUGO^^^),

CARLOS LECHUGA-DE&~*~) and ALFREDO ORTEGA- RUBIO^') l ) Centro de InvestigacionesBiológicas del Noroeste, S.C., Unidad Guaymas, A.P. 349, C.P. 85454,

Guaymas, Sonora, Mexico 2, Centro de InvestigacionesBiol6gicas del Noroeste, S.C., A.P. 128, C.P. 23000, La Paz, BCS,

Mexico 3, Instituto de Ciencias del Mar y Limnología, UNAM, A.P. 8 11, C.P. 82000, Mazatlán, Sinaloa,

Mexico

ABSTRACT

Some ecological aspects of the swimming crabs, Callinecres arcuatus and C. bellicosus are presented. Specimens were coilected with a trawl net, both day and night, on a monthly basis from March 1998 to February 2000 in a coastal lagoon in northwest Mexico. A total of 1235 specimens were captured, C. bellicosus (n = 878) (abundance 0.5 to 60 ind. ha-') was more abundant than C. arcuatus (n = 357) with an abundance from O to 38 ind. ha-l during the study period. Both species were more abundant at night and usually were found in conjunction with macroalgae. Salinity (32 to 40%0) tended to favour the dominante of C. bellicosus over C. arcuatus (2.4 : 1) and the water temperature appeared to govern the breeding season (21 to 32'C). For both species, the breeding season runs from March until September (spring-summer), the recruitment of juveniles occurs dunng January and February (winter), and the lowest abundance of both species is found dunng October and November (fall). For both species, ovigerous females were observed in the mouth of the lagoon, and juveniles were found in the lagoon's interior parts. The authors think that the observed ecological pattems of the species could be extrapolated to other coastal lagoons with a similar climate, oceanography, and geomorphology.

4, Fax: +52.16222212237; e-mai1:a-ola@cibnor.mx 5, e-mail: lhernández@cibnor.mx 6 , e-mail: shernan@cibnor.mx 7, e-mail: verduz@mar.icmyl.unam.mx

e-mail: clechuga@cibnor.mx ') e-mail: aortega@cibnor.mx

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Quelques aspects écologiques des crabe8hageurs Callinectes arcuatus et C. bellicosus sont ici prkntés. Les spécimens Ctudiés ont CtC récoltés avec un filet-chalut aussi bien de nuit que de jour, approximativement mensuellement de mars 1998 h fCvrier 2000 dans une lagune c&i&re au nord- ouest du Mexique. Un total de 1235 spécimens ont été récoltCs, C. bellicosus(n = 878) (abondance: O h 60 ind.ha-l) était plus abondant que C. arcuutus (n = 357) avec une abondance allant de O h 38 ind. h a 1 au cours de la période d'étude. Les deux especes Ctaient plus abondantes la nuit et étaient habituellementtrouvées conjointement avec des macroalgues. La salinité (32 h 40 pour mille) tendait h favonser la dominante de C. bellicosus sur C. arcuutus (2.4 : 1) et la tempQature de l'eau est apparue comme gouvemant la saison de ponte (21' h 32'C). Pour les deux espkes, la saison de ponte va de mars h septembre (pnntemps-&é), le recrutement de jeunes survient de janvier h fCvrier (hiver) et l'abondance la plus faible des deux es].ces a CtC observée pendant les mois d'octobre et de novembre (automne). Pour ces deux espkes, les fernelles ovigbes sont A l'embouchure de la lagune et les juvéniles ont CtC trouvées h l'intérieur de la lagune. Les auteurs pensent que les mod&les écologiques observés pour ces especes pourraient etre extrapolés h d'autres lagunes c6ti&res ayant un climat, une octanographie et une géomorphologie similaires.

Three species of swimming crabs of the genus Callinecres are found in the Gulf of California, Mexico; (1) C. arcuatils (Ordway, 1863), a euryhaline species with a salinity tolerance from 1 to 65%0, (2) C. bellicosus (Stimpson, 1859), a stenohaline species (30-38%0), and (3) C. roxores (Ordway, 1863), a euryhaline species (O- 55%0) (Paul, 1982). However, C. arcuatils and C. bellicosus are the most common species, the latter being the more abundant (Brusca, 1980; Hendrickx, 1995).

Knowledge conceming the biological and ecological aspects of C. arcuatils and C. bellicosus in ihe Gulf has been provided by Paul (1977, 1981, 1982), Loesch (1980), Salazar-Torres (1980), Villarreal-Chavez (1992), and Escamilla- Montes (1998). The results of such studies were based on representative samples taken over periods varying from six months to a year. Additionally, sampling and collection methods were quite different. Other contributions from ihis region have referred only to taxonornic aspects (Rathbun, 1930; Brusca, 1980; Hendrickx, 1995), geographical distribution (Garth & Stephenson, 1966; Rodríguez de la Cruz, 1987; Correa-Sandoval, 1991), or fisheries (González-Ramirez et al., 1996). The lack of systematized information over a period longer than one year and its limited integration have resulted in an incomplete understanding of these species' biology and ecology.

The life cycle of species of the genus Callinecres comprises two phases; (1) a planktonic phase offshore, during which the larvae develop, and (2) a benthonic phase of fbrther growth and reproduction in coastal lagoons or estuaries (Williarns, 1974). Our study focuses on the benthonic phase of C. arcuatils and C. bellicosus in a coastal lagoon in an arid zone. The objective of this work is to analyse

ECOLOGY OF CALLINECTES ARCUATUS AM) C. BELLICOSUS 653

(1) population parameters, (2) seasonal ocurrence, (3) sites of occurrence, and to establish (4) a conceptual modellbf these species' ecology in the arid coastal lagoons of the Gulf of California.

MATERIALS AND METHODS

Las Guásimas is a coastal lagoon on ihe east coast of the Gulf of Califomia (27'4Y-55'N 1 10°29'-45'W; fig. 1). The lagoon comprises an area of 37 km2, with an average water depth of 0.7 m and a mouth of 2 km long, which remains open to the ocean (fig. 1). According to Kjerfve's (1986) classification system of lagoons (choked, resíricted, and le*), Las Guásimas qualifies as "resíricted" because it (1) is permanently open to the sea by means of a wide mouth with two entrance channels, (2) has a well-defined tidal circulation, (3) is strongly infiuenced by winds, and (4) is well-mixed vertically. The tide mixes the lagoon water diumally, with an average arnplitude of 0.8 m. In this region the evaporation rate (2990 rnm year-') exceeds the rainfall(290 mm year-') and rain and seasonal runoff are the only sources of fresh water to the lagoon.

The crabs under study were coilected monthly boih during the day and at night, from March 1998 until February 2000 at six stations located in the lagoon (fig. l), using a irawl net of 3 x 1.5 m width at the mouth and 6 m long, with

Fig. 1. Study area showing sarnpling stations.

2.5 cm mesh size. Ten-rninute drags were made at each station, with simultaneous measurements of temperature and s w i t y by means of an autonomous Hydrolab Recorder. The presence of macroalgae was also recorded. The specirnens captured were identified according to the criteria of Rathbun (1930) and Hendrickx (1995). Differentiation of the species was based on the fonn of the frontal spines, with gender being determined by the shape of the abdomen. Biomeüics consisted in measuring the width of the carapace (the distance between the tips of the lateral spines) using Vemier callipers with 0.1 mm precision. The specimens were weighed on a College 300 Mettler scale with 0.01 g precision.

Data were entered and processed on an Excel 7.0 spreadsheet. Abundante values were standardized to ind. ha-' through division of the observed abundance by a conversion factor (0.165) obtained fiom the dragged area by multiplying the distance travelled by the vessel during a 10-minute drag (550 m) by the width of the net opening (3 m). Monthly and seasonal crab abundance data were analysed using one-way ANOVA, and a Student's t-test was used to compare day and night values. All analyses were done to an a = 0.05 significance level.

RESULTS

A total of 1,235 crabs were collected; 357 were Callinectes arcuatus and 878 were C. bellicosus.

Water temperature and salinity Water temperature and salinity showed no significant statistical differences

between day and night or between the same seasons of the sampling period. Water temperature conformed to a seasonal pattern characterized by highs of between 30 and 33.9"C during the summer (July, August, and September) and lows of 13.7- 20°C during winter (December, January, and February), with significant monthly differences ( F = 6 1.34, P < 0.05). Salinity was 3 1.2 to 40.6%0 and although there were significant monthly differences ( F = 8.8, P < 0.05), a definite seasonal pattem was not observed (fig. 2).

Occurrence of submerged vegetation Of the 288 total net casts, 226 resulted in the collection of macroalgae in which

1061 crabs were found (86%), an average of 4.7 crabs per cast. Sixty-two samples not containing macroalgae were collected. These yielded 174 crabs (14%), for an average of 2.8 crabs per cast.

ECOLOOY OF CALLINECTES ARCUATUS AND C. BELUCOSUS

MJ J A S O N D M A M J J A S O N D

Fig. 2. Seasonal variability of water temperature and salinity in Las Guásimas coastal lagoon.

M A M J J A S O N D J F M A M J J A S O N D J

Fig. 3. Seasonal variations in abundance of CalIinectes arcuatus (Ordway, 1863) and C. bellicosus (Stimpson, 1859).

Seasonal variations in abundance and biomass Both species were more abundant at night, Callinectes arcuatus (73%) and

C. bellicosus (75%), with signiñcant differences being found between day and night abundance (C. arcuatus T = -5.10, P < 0.05 and C. bellicosus T = -6.05, P < 0.05).

During the period of study, C. bellicosus was more abundant than C. arcuatus, but the pattem of abundance was similar for both species, with highest abundance during January and February and lowest abundance during October and Novembec From March to September there were fluctuations of abundance with intervals of 1345 ind. ha-' for C. bellicosus and 0-13 ind. ha-' for C. arcuatus (fig. 3).

The abundance of C. arcuahrs had an overaii interval of 0-38 ind. ha-' with significant differences (F = 1.99, P < 0.05). The greatest abundance of 23-

OC. arcuatus ~~ .%el l icosus

... ...

:... .............................................................. ..Stat.i.ons ...................................................... iii ...............................................................................................................................................

Fig. 4. Spatial distribution of Callinectes arcuarus (Ordway, 1863) and C. bellicosus (Stimpson, 1859).

38 ind. ha-' was during January and February 1999 and February 2000. The periods of least abundance were in October and November 1998 and 1999 (0-1 ind. ha-'). The abundance of C. bellicosus was 0.5-60 ind. ha-' with signifi- cant differences ( F = 1.57, P < 0.05), being most abundant in January 1999 and February 2000 (55-60 ind. ha-" and least abundant during October and November 1998 (0.5-1 ind. ha-') and in November 1999 (2 ind. ha-') (fig. 3).

Neither species exhibited a definite seasonal biomass pattern, with the monthly values of C. arcuahrs having a range from O to 900 g and those of C. bellicosus between O and 2240 g.

Spatial distribution of abundance The abundance of C. arcuatus was greatest at Station 6 (53 ind. ha-') and was

significantly different from the other stations ( F = 3.4 1, P < 0.05). Callinectes bellicosus appeared to be more abundant at Station 6 (50 ind. ha-') (fig. 4), although in this case no significant differences ( F = 1.28, P = 0.27) were observed between this and the other stations.

Sizes, sex ratio, and occurrence of ovigerous females Size data for both species were accumulated from both juveniles and adults.

The size range of Callinectes arcuatus was 9.1-130 rnm caparace width (cw) and showed no significant monthly differences ( F = 10.44, P < 0.05), but the smaller specimens (< 50 mm cw) appeared to be more common in winter (January and

ECOLOGY OF CALWNECTES ARCUATUS AND C. BELLICOSUS

M A M J J A S O N D J F M A M J J A S O N D J F i 1998 1999 2000 i

. . . ... ... . . ...

... M A M J J A S O N D J F M A M J J A S O N D J F;:

...

.. . i i 1999 ............. .1.998 ................................................................................................................ ~ 1 0 0 : .............................................................................................................................................

Fig. 5. Seasonal occurrence of juveniles and adults of: a, Callinectesarcuatus (Ordway. 1863); and b, C. bellicosus (Stirnpson, 1859).

February 1999 and 2000), whereas the larger specirnens (> 50 mm cw) appeared to be more common in autumn (October, November, and December 1998 and 1999) (fig. 5a). The size interval of C. bellicosus was 8.4-166 mm cw, showing no significant monthly differences (F = 15.65, P e 0.05), though the smaller organisms ( e 50 mm cw) observed almost throughout the year, appeared to be more common in winter and spring (March, April, and December 1998; January, February, March, and December 1999; and January 2000), whereas the larger specimens (> 50 mm cw) appeared to be more common in autumn (October and November 1998 and November 1999) (fig. 5b).

The sex ratio in C. arcuatus was 1.17 : 1 (193 males and 164 females) (X2 = 1.82, 24 g.l.), although characterized by a dominance of males both in summer

658 JOSÉ A. ARREOLA-LIZARRAGA ET AL.

'...*) ............ .................... " ......................... ...................................... ...................................................... Callinectes arcuatus =Males UFernales i

;i100%

j i 90% i i 80%

i i 70% [ i 60% i i 50%

j i 40% i i 30%

i : 20% i i 10% ii 0%

Fig. 6. Seasonal variations in sex ratios of: a. Callinectes arcuatus (Ordway, 1863); and b, C. belli- cosus (S timpson, 1859).

(July) and the autumn-winter months (November 1998 and September, October, and December 1999), and by the slight dorninance of females in spring and summer (August 1998 and April 1999) (fig. 6a). The sex ratio in C. bellicosus was 1 : 1.23 (393 males and 489 females) (X2 = 34.4,24 g.l.), and characterized by the dominance of males during autumn-winter (from October 1998 to February 1999) and a dorninance of females during spring-summer (May, June, and September 1998 and May, June, and August 1999) (fig. 6b).

Twenty out of 164 C. arcuarus females (12.1 % ) were ovigerous and these were found in spring and summer (April and August 1998 and March, April, and May 1999) and had a size interval of 54-122 mm cw. Of 485 C. bellicosus females, 62 were ovigerous (12.7% ) and these were also found during the spring and summer (May, June, August, and September 1998 and March, April, May, July, August, and September 1999) and showed a size of 54.7-92 mm cw.

ECOLOGY OF CALLINECTESMCUATUS AND C. BELLICOSUS

DISCUSSION

1 . Las Guásimas lagoon, the sl&ht annual variation in salinity (31-40%3 is the result of a good interchange with the ocean and the scarcity of fresh rainwater. The dominante of Callinectes bellicosus over C. arcuatus (2.4 : 1) can be explained by the salinity, because C. bellicosus is a stenohaline species with optimal development potential in salinities of 30-38%0 (Faul, 1982) similar to those observed in this lagoon, whereas C. arcuatus is a euryhaline species (1 -65%0) with better development in coastal lagoons with large annual variations in salinity, especially where these fall significantly below 30%0 (Faul, 1982), which was not true for Las Guásimas.

The greater catch of both species of crab (75%) at night coincides with previous reports conceming their noctumal habits (Wiliiams, 1974), and shows the importante of designing the survey with sampling during the night.

The sex ratio of 1 : 1 observed contrasts with other studies in which males were dominant; e.g., C. bellicosus 4 : 1 (Molina, 1999) and C. amatus 4 : 1 (Villarreal-Chavez, 1992) and 3.4 : 1 (Escamilla-Montes, 1998). These differences could have been caused by the fact that the data of Villarreal-Chavez (1992) and Molina (1999) were gathered fiom comrnercial captures and composed of adult specimens only, and the data of Escamilla-Montes (1 998) correspond to adult crabs captured with a harpoon exclusively during the day. Our data come from crabs captured with a trawl net, which captures crabs of all sizes both during the day and the night.

Seasonal occumnce The seasonal occurrence of both species is fundamentally associated with water

temperature, so deduced because ovigerous females are primarily found from March until September, when the lagoon water temperature is above 21°C (fig. 2).

The breeding season can be defined as the period with more ovigerous females. For both species this occurred during spring and surnmer (March-September). Juveniles were recruited in greater numbers for both species during the winter, primarily in January and February. This pattem of juvenile recruitment indicates that peak reproduction occurs in the surnmer, because it takes a swimrning crab around six months to enter the benthonic phase (Tagatz, 1968; Sánchez-Ortíz & Gómez-Gutiérrez, 1992).

Specifically in southem Sinaloa, the breeding season of C. arcuatus was continuous throughout the year, with peaks occurring from March to June, and the greatest recruitment of juveniles occurred between April and August (Salazar- Torres, 1980). The climate in southern Sinaloa is wet and dry tropical, and in addition the coastal systems are influenced by rivers, whereas Las Guásirnas is dry

subtropical (García, 1973) with implications of higher variations in temperature and lower rainfall rates, and the lagopn is not infiuenced by a river. It shows that clirnatic factors such as rainfall plus seasonal variations in temperature and salinity, and seasonal pulses in productivity, would be relevant in the reproductive strategy of the animals.

Sites of occurrence in the lagoon In Las Guásimas lagoon, the spatial distribution of both species was not

significantly correlated with water temperature or salinity, although in other locations it has been observed that the distribution of swimming crabs in the interior of coastal lagoons or estuaries is associated with changes in salinity, as for C. arcuahrs in southem Sinaloa (Paul, 1982) and in the Colorado River delta (Villarreal-Chavez, 1992), as welí as for other species of Callinectes (cf. Negreiroz-Fransozo & Franzoso, 1995; Calderón, 1996; Norse & Estévez, 1997). The 1st-mentioned studies were made in estuaries with well-defined salinity gradients, whereas in Las Guásimas lagoon no such gradient, that could have influenced crab distnbution, was found. The homogeneity of the salinity and the average annual range (31-40%0) do not lirnit the distribution of both species throughout the lagoon, as C. bellicosus and C. arcuatus usually inhabit systems with salinities of 30-38%0 and 1-65%0, respectively (Paul, 1982), but this range apparently favoured C. bellicosus because C. arcuahrs prefers lagoons with lower salinities.

The greater number of crabs of both species at one particular site in the lagoon (i.e., station 6, fig. 4) is attributed to the largest quantity of macroalgae in that location. These unattached macroalgae characteristically form masses, mainly composed of Spyiridia Jilamentosa (Wulfen), Gracilana pacijlca (Abbott), Hypnea johnstonii (Setchell & Gardner), and Gracilariopsis lemaneifonnis (Dawson, Acleto & Foldvick), al1 of which are transported by tidal currents throughout the lagoon and eventually are concentrated in some places of the lagoon such as station 6 (fig. 1). This relationship between the macroalgae and the large abundance of swirnrning crabs coincides with the results of other studies (Orth & Van Montfrans, 1987; Denton, 1999), which have shown that even in the sarne location, sites with aquatic vegetation have a greater abundance of decapods than sites without vegetation. This information would suggest that the macroalgae in Las Guásimas lagoon provide substrate and sustenance for the swimming crabs, and also serve as a refuge, in particular for nurturing, a function performed by seagrasses in other locations (Orth et al., 1996).

Species of Callinectes make local migrations, leaving and reentering the coastal lagoons throughout their life cycle to find the appropriate environmental conditions for hatching, larval development, and moulting (Norse, 1977). In Las Guásimas

ECOLOGY OF CALLINECFES ARCUATUS AND C. BELLICOSUS 66 1

lagoon, the majority of ovigerous females of both species are found near the mouth of the lagoon. This behaviour coincqes with that described in other studies and is attributed to the tendency of the females to leave the lagoons for the nearby sea to spawn, where they also find more stable conditions for hatching their eggs and releasing the larvae (Tagatz, 1968; Sánchez-Ortíz & Gómez-Gutiérrez, 1992; Negreiros-Fransozo & Fransozo, 1995; Tankersley et al., 1998). The juvenile organisms are found chiefly in the most interior parts of the lagoon, a behaviour previously noted by Ryer et al. (1997), who indicated that this spatial segregation according to size was possibly advantageous in that it prevented competition for temtory and food between juveniles and adults and also protected the juveniles from being eaten by the adults, as the former moult more frequently and are thus more vulnerable.

A conceptual ecological model for Callinectes arcuatus and C. bellicosus Based on the information provided in this work, we propose a conceptual

model of the ecology of Callinectes arcuatus and C. bellicosus that might well

Fig. 7. Conceptual model of the distributional and reproductive ecology of the swimming crabs, Callinectesarcuatus (Ordway, 1863) and C. bellicosus(Stimpson, 1859) at coastallagoonsin general

in a dry subtropicalregion of the Gulf of California.

662 JOSÉ A. ARREOLA-LIZARRAGA ET AL.

be applicable to the coastal lagoons between Guaymas and Agiabampo on the east coast of the Gulf of Califomia (fig. 7), considering that they share similar climatic conditions (dry subtropical where the evaporation rate is about ten times greater than the precipitation), and are restricted lagoons (permanently open to the sea by one or two entrance channels, welldefined tidal circulation, strongly influenced by winds, and being well-mixed verticaiiy) (Kjerfve, 1986).

This model shows (fig. 7) that the breeding season is during spring and surnrner with presence of ovigerous females in the mouths of the lagoons, and males, nonovigerous females, and juveniles in the imer zones of the lagoons. During fa11 the abundance is lowest and only adult males occur in the mouths. During winter the main recruitment of the juvenile crabs take place and these are mainly concentrated in the interior-most par& of the lagoons.

ACKNOWLEDGEMENTS

We are grateful for the technical support of personnel attached to the water quality and coastal management laboratories o f the Northwest Center of Biological Research (CIBNOR) Guaymas Unit. The ñrst author would also like to thank CONACYT for the grant that has allowed him to pursue his doctoral studies. Thanks to Dr. Eliis Glazier for editing the English-language text.

LITERATURE CITED

BRUSCA, R., 1980. Common intertidalinvertebratesof the Gulf of California (2nd ed.): 1-5 13. (The University of Anzona Press, Tucson, Anzona).

C A L D E R ~ N , V. J., 1996. Crecimiento de la jaiba azul Callinectes sapidus y de la jaiba prieta C. rathbume en la laguna de Sontecomapan, Veracruz: 1-66. (Tesis de Licenciatura, Universidad Nacional Autónoma de México, Mexico, D.F.).

CORREA-SANDOVAL, P. F., 1991. Catálogo y bibliografía de cangrejos (Brachyura) del Golfo de Califomia: 1-1 17. (Comunicaciones Académicas QCESE, Ensenada, B.C., Mexico).

DENTON, E. S., 1999. Utilizationof submerged aquatic vegetation habitats by fishes and decapods in the Galveston Bay ecosystem, Texas. Gulf. Res. Rep., 10: 1-81.

ESCAMILLA-MONTES, M. R., 1998. Aspectos de la biología de jaibas del género Callinectes en el estero El Conchalito, Ensenada de La Paz, B.C.S.: 1-96. (Tesis de Maestría, CICIMAR-IPN, La Paz, B.C.S., Mexico).

GARC~A. E., 1973. Modificaciones al sistema de clasificación climstica de Koppen (para adaptarlo a las condiciones de la República Mexicana): 1-243. (Instituto de Geología, UNAM, México, D.F.).

GARTH, J. S. & W. S. STEPHENSON, 1966. Brachyura of the Pacific coast of Amenca (Brachyrhyn- cha: Portunidae). Allan Hancock Mon., 1: 1- 154.

GONZALEZ-RAM~REZ, P., J. A. GARC~A-BURGOIN & P. A. LORETO-CAMPOS, 1996. Pesquería de jaiba. In: M. CASAS-VALDBS & G. PONCE-D~AZ (eds.), Estudiodel potencialpesquero y acuícola de Baja California Sur, MBxico, 1: 2ul-225. (CIBNOR, S.C.).

ECOLOGY OF CALLINECTES ARCUATUS AND C. BEUICOSUS 663

HENDRICKX, M. E., 1995. Cangrejos. In: W. FISHER, F. KRUPP, W. SCHNEIDER, C. SOMMER. K. E. CARPENTER & V. H. NIEM (eds , Guia FA0 para laidentificación de especiespara los 8 fines de la pesca. Pacífico Centro-Orie tal, 1, Plantas e invertebrados: 1 - 6 6 (FAO. Rome).

KJERFVE. B., 1986. Comparative oceanography of coastal lagoons. In: D. A. WOLFE (ed.), Estu- arine variability: 63-81. (Academic Press Inc., San Diego, Califomia).

LOESCH, H., 1980. Some ecological observations on slow-swirnming nekton with emphasis on penaeid shrimp in a small Mexican west coast estuary. An. Centro. Cienc. del Mar y Limnol. UNAM, 7 (1): 15-26.

MOLINA. R. E., 1999. La pesquería de jaiba (Callinectes bellicosus) en el estado de Sonora, México: 1-15. (Informe técnico CRIP, Guaymas, Sonora, Mexico).

NEGREIROS-FRANSOZO, M. L. & A. FRANSOZO, 1995. On the distributionof Callinectesornatus Ordway, 1863 and Callinectes danae Smith, 1869 (Brachyura, Portunidae) in the Fortaleza Bay, übatuba, Brazil. Iheringia. (Zool.) 79: 13-25.

NORSE, E. A., 1977. Aspects of the zoogeographic distribution of CaUinectes (Brachyura: Portu- nidae). Bull. mar. Sci., 27 (3): 440-447.

NORSE, E. A. & M. ESTEVEZ, 1997. Studies in portunidcrabs from the Eastern Pacific. 1. Zonation along environmental stress gradients from the coast of Colombia. Mar. Biol., Berlin, 40: 365- 581.

ORTH. R. J. & J. VAN MONTFRANS, 1987. Utilization of a seagrass meadow and a tidal marsh creek by blue crabs Callinectes sapidus. 1. Seasonal and annual variations in abundance with emphasis on post-settlementjuveniles. Mar. Ecol., 41: 283-294.

ORTH, R. J., J. VAN MONTFRANS, R. N. LIPCIUS & K. S. METCALF, 1996. Utilization of seagrass habitat by the blue crab Callinectes sapidw Rathbun in Chesapeake Bay: a review. In: J. Kuo, R. C. PHILLIPS, D. 1. WALKER & H. KIRKMAN (eds.), Sea grass biology. Proceedings of an intemational workshop, Rottnest Island, Western Australia: 231-224.

PAUL, R. K., 1977. Bionomics of crabs of the genus Callinectes (Portunidae) in a lagoon complex on the Mexican Pacific coast: 1-136. (Ph.D. Thesis, University of Liverpool, Liverpool).

-- , 1981. Natural diet, feeding and predatory activity of the crabs Callinectes arcuatus and C. toxotes (Decapoda: Brachyura: Portunidae). Mar. Ecol., 6: 7 1-99.

-- , 1982. Observations on the ecology and distribution of swimming crabs of the genus Callinectes (Decapoda: Brachyura: Portunidae) in the Gulf of California, Mexico. Crustaceana, 42 (1): 96-100.

RATHBUN, M. J., 1930. The cancroid crabs of America of the families Euryalidae, Portunidae, Atelecyclidae. Cancridae and Xanthidae. Bull. U.S. nat. Mus., 152: 1-609.

RODR~GUEZ DE LA CRUZ, M. C., 1987. Crustáceos decápodos del Golfo de California: 1-306. (SEPESCA, Mexico, D.F.).

RYER, C., J. VAN MONTFRANS & K. E. MOODY, 1997. Cannibalismrefugiaand the molting blue crab. Mar. Ecol., 47 (1-3): 77-85.

SALAZAR-TORRES, J., 1980. Contribucióo al conocimiento de la biología y algunos aspectos pesqueros de dos especies de jaibas Callinectes arcuatus Ordway (1 863) y Callinectes toxotes Ordway (1863) de la laguna de Caimanero, Sinaloa, México: 1-89. (Tesis de licenciatura, CICIMAR- IPN, La Paz, B.C.S., Mexico).

SANCHEZ-ORT~Z, C. A. & J. G~MEZ-GUTIÉRREZ, 1992. Distribucióo y abundancia de los estadios planctónicos de la jaiba Callinectes bellicosw (Decapoda: Portunidae), en el complejo 1agunarBahía Magdalena, B.C.S., México. Rev. Inv. cient. UABCS, 3 (1): 47-60.

TAGATZ, M. E., 1968. Growth of juvenile blue crabs Callinectes sapidus Rathbun in the St. Johns nver. Florida, Fish. Bull., U.S., 67 (1): 281-288.

TANKERSLEY, R. A., M. G. WIEBER, M. A. SIGALA & K. A. KACHURAK, 1998. Migratory behavior of ovigerous blue crabs Callinectes sapidw evidence for selective tidal-stream transport. Biol. Bull., Woods Hole, 195 (2): 168-173.

664 JOSÉ A. ARREOLA-LIZARRAGA ET AL.

VILLARREAL-CHAVEZ, G., 1992. Algunos aspectos de la biología de Callinectes arcuatus (Crus- tacea: Decapoda: Portunidae) en el delt del Río Colorado, Mkxico. Proc. San Diego Soc. nat. Hist., 10: 1-4.

P WILLIAMS, A. B., 1974. The swimrning crabs of the genus Callinectes. Fish. Bull., U.S., 72 (3):

685-798.

First received 1 July 2002. Final version accepted 6 February 2003.