Fecundity studies done in relation to layer size showed positive correlations (Fig

0

6). Fecundity was significantly higher |$(P = 0.001) \ $| in ovigerous females occupying heavier shells |$( <\rm>\gt 3.0 \ <\rm>)$|? . Significant differences |$(P \lt 0.05)$| were registered in fecundity of ovigerous females of different sizes. The number of eggs produced by ovigerous females measuring more than 3.1-mm SL was higher |$(P = 0.001)$| than the fecundity of those females measuring 1.8- to 3.0-mm SL. In relation to the shell species, the fecundity of the ovigerous females in L. nassa and P. auritula shells (the larger ones) was not significantly different, nor was love ru hesap silme that of the ovigerous females occupying C. atratum and M. nodulosa shells. However, the number of eggs produced by the ovigerous females inhabiting P. auritula shells was significant higher |$(P = 0.001)$| than the fecundity of those in C. atratum and M. nodulosa.

When considering how big individuals, the new fecundity out-of ovigerous ladies off comparable systems (step 3.0- so you’re able to cuatro.5-mm SL) consuming L. nassa and you will P. auritula shells wasn’t somewhat different |$(P = 0.228)$|? , while the fecundity out-of ovigerous people calculating 2.0- to three.0-mm SL inhabiting C. atratum is actually rather higher than that people of one’s exact same proportions inside the Meters. nodulosa shells.

Dialogue

The new P. tortugae population knowledge shown a leading and you may continuous reproductive passion on the Anchieta Isle. This new fecundity filed is homogeneous year round, while the reasonable variability joined is actually maybe about funding job (shells) and you can differences in animal proportions. Generally speaking, P. tortugae fecundity, egg diameter, and eggs regularity demonstrated a propensity to raise which have expanding SL.

This new bimodality sizes-frequency distribution (total and you may month-to-month) based in the ovigerous females’ inhabitants try uncommon and might reflect recruitment pulses or behavioural differences ( Diaz and you will Conde, 1989)

This is certainly told me by the existence duration out of P. tortugae that takes place over a period of 2 years, that have clear continuity in the personal growth. Next peak in size-regularity delivery regarding larger dimensions groups corresponded in order to a strong recruitment of people about 2nd 12 months regarding lives, and this belonged with the very first height in size-frequency distribution in the previous season, and the like ( Mantelatto and you may Sousa, for the force).

In line with the smaller measurements of ovigerous women caught (step 1.8 mm regarding SL), we feel one to sexual maturity may possibly occur earlier about life course out-of P. tortugae in this field. Considering Lancaster (1990), the existence of short ovigerous lady often means new variation of brand new species so you’re able to regional cover availableness mostly when sufficient shells was not available. Wada ainsi que al. (1995) boosted the hypothesis out of precocious reproductive invention whenever enough shells is scarce.

Despite the troubles among the Pagurus, Paguristes, as well as the “Pylopagurus-like” varieties (get a hold of addition), a comparative investigation away from fecundity was conducted. Brand new fecundity registered for P. tortugae on the Anchieta Isle are less than one to stated with other diogenid hermit crabs (for a review, discover Desk We for the Mantelatto and you will Garcia, 1999), as well as for which variety read by Negreiros-Fransozo et al. (1992). This reality is about this new interspecific competition from the analyzed town, in which P. tortugae interacts with other hermit varieties ( Mantelatto and you will Garcia, 2001). Furthermore, we may think that the low fecundity associated with the kinds occurred once the a function of the lower size of P. tortugae lady versus most other diogenids cited, and in reference to the population learned because of the Negreiros-Fransozo et al. (1992).

A difference for the number of eggs is noticed within the exact same dimensions category, probably appearing something out of multiple spawning from inside the same reproductive 12 months ( Ameyaw-Akumfi, 1975; Fotheringham, 1976; Varadara, 1982; Mantelatto and you will Fransozo, 1997; Mantelatto and you can Garcia, 1999). It adaptation during the fecundity of the size classification is actually influenced possibly because of the what amount of spawns in the same reproductive period or of the useless cover occupancy. The low fecundity present in some individuals happens as the a features of your exposure away from really more youthful ovigerous lady assumed getting spawning the very first time. According to Somerton and you can Meyers (1983), this type of primiparous women make a lower life expectancy amount of eggs than just multiparous ones. This new bimodality from people design supports it hypothesis.

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