New hermit crab shield duration research was submitted to a good Kruskal-Wallis decide to try, a non-parametric method that’s not established of normal delivery, based on SOKAL ROHLF (1995), from the a great 5% advantages top, to spot any potential difference in dimensions ranging from genders
In terms of almost every other hermit crab kinds, new broad geographical shipments away from Clibanarius vittatus (Bosc, 1802) was said by the its higher tolerance so you can bad ecological conditions owed to utilize out-of gastropod shells to protect its fragile abdomen (REESE, 1969). The layer used by a good hermit crab will likely be possibly located blank, obtained because of the confrontations anywhere between personal crabs, or by eliminating the latest gastropod (ELWOOD NEIL, 1992). The availability of shells is an essential parameter stated in the previous degree (ORIANS King, 1964; NEGREIROS-FRANSOZO mais aussi al., 1991; PINHEIRO ainsi que al., 1993; TURRA LEITE, 2001), which will be the main basis restricting populations off hermit crabs (PROVENZANO, 1960; BOLLAY, 1964; REESE, 1969; HAZLETT, 1970).
Hermit crabs will often have specific choice to possess gastropod shell kinds (REESE, 1962; ORIANS Queen, 1964; BERTNESS, 1980). This preference is relevant to cover frameworks and you will dimensions (CONOVER, 1978). Hermit crabs hence consume large shells can also be better overcome to desiccation, thermal be concerned and you can predation (RITTSCHOF ainsi que al., 1995). A massive gastropod shell provides a generous interior city, which is beneficial having somatic growth (HAZLETT, 1981). Yet not, hefty shells could possibly get maximum breeding and you will growth (BERTNESS, 1981; OSORNO ainsi que al., 1998), from the high energy rates to own locomotion. At contrary, brief shells give the fresh new crabs more susceptible to help you predation hiki and ), given that crabs you want large shells for ecdysis in their ontogeny (, 1976a, b).
In spite of all these points and possess buy choices and you can shell utilization, there is usually a strong relationship between the cover dimensions and you will the size of new crab (ABRAMS, 1980; HAZLETT, 1981; ABRAMS et al., 1986). The purpose of the current data were to gauge the development out-of gastropod shell use because of the C. vittatus, and also to ensure the very first biometric emails to have cover choice.
This new empirical circumstances of those biometric relationship have been submitted to regression analyses because of the fuel form (y = ax b ), toward most useful fit indicated because of the determination coefficient (r dos )
Pescadores Coastline (23?58’21”S; 46?23’35”W), found in the estuarine station off Sao Vicente, Condition regarding Sao Paulo, Brazil, slots a diverse marine fauna, including molluscs, macroalgae and you may benthic crustaceans in the intertidal zone.
This new hermit crabs had been handly captured throughout reasonable tide, out-of . A couple obtained the new crabs, month-to-month, having ten minutes; this time is situated to help you standardize brand new get efforts on the chronilogical age of study. Liquids salinity (?) is counted per month.
From the laboratory, the fresh specimens have been identified predicated on MELO (1999), and gastropod shells based on RIOS (1994). New crabs with the gastropod shells was basically stored suspended up to analysis. The newest crabs and you may shells were mentioned having fun with an effective vernier caliper, towards nearest 0.01 mm. This new carapace protect length (CSL) is actually filed regarding the suggestion of one’s rostrum towards midpoint of your own cervical groove. The fresh layer total length (SL) and you may aperture size (AL) was indeed plus mentioned. From the second seasons of the data, the newest hermit crab weight (HW) and their cover moist pounds (WW) was basically calculated from inside the an accuracy balance (0.01 g); just after range-drying at 60 ?C to have twenty four h, this new shells were weighed once again so you can list the fresh new dead lbs (DW).
The shell utilization development for the personal groups of C. vittatus (guys, girls, ovigerous female and you may intersexual specimens) is actually analyzed by the relative frequency for the step 1 mm dimensions-groups (STURGES, 1926).
The newest shell parameters SL, AL, WW and you can DW was basically noticed oriented and you can were correlated with hermit crab morphometric parameters (CSL and you can HW), removed because separate details.