title: Sex-specific mediation of foraging in the shore crab, Carcinus maenas.
abstract: Experiments were conducted to investigate the sex-specific differences to feeding responses of the shore crab Carcinus maenas throughout the year. Results demonstrate that female shore crabs exhibit stronger feeding responses than males throughout the year with a significantly reduced feeding response in males during the summer months' reproductive season. We also studied the possible function(s) of the moulting hormone, 20-hydroxyecdysone (Crustecdysone) that has been described as a potential female-produced sex pheromone to initiate male reproductive behaviour in a number of crustaceans. We recently presented evidence that for shore crabs this is not the case and now show that the steroid is instead functioning as a sex-specific feeding deterrent protecting the moulting 'soft' female crabs. Whilst male shore crabs were deterred from prey (Mytilus edulis) and synthetic feeding stimulants glycine and taurine when these feeding stimulants were spiked with crustecdysone, intermoult female crabs were significantly less affected and rarely deterred from feeding. This sex specificity of the moulting hormone, in combination with the female sex pheromone, which has no anti-feeding properties, ensures that male crabs mate with soft-shelled, moulted females rather than engage in cannibalism, such as found frequently in cases when soft-shelled females are exposed to intermoult females.
authors.affiliation: Cardiff School of Biosciences, Cardiff University, CF1 3TL, UK.
authors.forename: Dominic
authors.initials: D
authors.lastname: Hayden
authors.forename: Alice
authors.initials: A
authors.lastname: Jennings
authors.forename: Carsten
authors.initials: C
authors.lastname: Müller
authors.forename: David
authors.initials: D
authors.lastname: Pascoe
authors.forename: Ralf
authors.initials: R
authors.lastname: Bublitz
authors.forename: Heather
authors.initials: H
authors.lastname: Webb
authors.forename: Thomas
authors.initials: T
authors.lastname: Breithaupt
authors.forename: Lloyd
authors.initials: L
authors.lastname: Watkins
authors.forename: Jörg
authors.initials: J
authors.lastname: Hardege
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D003386:Brachyura / Q000737:chemistry / Q000502:physiology*; D004441:Ecdysterone / Q000032:analysis / Q000502:physiology; D005247:Feeding Behavior / Q000502:physiology*; D005260:Female; D005998:Glycine / Q000032:analysis; D008297:Male; D012621:Seasons; D012727:Sex Characteristics; D012726:Sexual Behavior, Animal / Q000502:physiology
chemical_list: D004441:Ecdysterone; D005998:Glycine