The effects of sex ratio on the spawning frequency of females and on male mating behavior were examined in the spiny king crab, Paralithodes brevipes. Two types of guarding behavior were categorized based on when the male began guarding the female, that is, pre- and post-molting types, when the male starts guarding the female either before or after her molt, respectively. Males reared under a female-biased sex ratio more often showed the post-molting type than did males reared under an even ratio. Guarding duration for the pre-molting type, from the start of guarding to female molting, was significantly longer when the sex ratio was even than when females were more numerous (female : male ratio = 5:1). While there was no significant difference in the molting frequency of females between the two sex ratios, frequencies of egg extrusion were significantly lower for the female-biased ratio than for the even sex ratio. These results suggest that the sex ratio affects the mating behavior of P. brevipes and might be an important factor to manage wild populations and to produce seed crabs effectively in nursery tanks.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 20 • No. 3