Does male-biased predation lead to male scarcity in viviparous fish?

Citation
Cm. Garcia et al., Does male-biased predation lead to male scarcity in viviparous fish?, J FISH BIOL, 53, 1998, pp. 104-117
Citations number
34
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Aquatic Sciences
Journal title
JOURNAL OF FISH BIOLOGY
ISSN journal
0022-1112 → ACNP
Volume
53
Year of publication
1998
Supplement
A
Pages
104 - 117
Database
ISI
SICI code
0022-1112(199812)53:<104:DMPLTM>2.0.ZU;2-9
Abstract
Male predation risk due to ornaments seldom reduces female mating opportuni ties because males escape costs through alternative mating strategies and/o r females cease to select for highly ornamented males. Males of the Amarill o fish Girardinichthys multiradiatus (Goodeidae) have large sexually select ed fins that impair attack-avoidance manoeuvres. This fish was used to seek evidence that intersexual selection for handicapping traits can result in a deficit of acceptable mating partners. Also it was examined whether, unde r male scarcity, females remain choosy to the point of missing mating oppor tunities, and that they can exert effective control over matings, which is a pre-condition of effective female choice. It was found that snakes prey d isproportionately on males. that it leads to female-biased sex ratios. and that highly ornamented males are more scarce after predation than males wit h small ornaments. Females can avoid being fertilized by unattractive males . and that missing one reproductive period can lead to infertility. Thus it appears that females have promoted the exaggeration of a male trait that i ncreases predation risk, remain choosy even when acceptable males are scarc e, and pay a large cost when missing mating opportunities. A prediction fro m these results is that females enjoy substantial fitness benefits from mat ing with highly ornamented males, which override the occasional fatal costs of refusing to mate with sub-optimal males. One potential consequence of f emale selectivity and control over matings when males are scarce may be a r educed capability to colonize new habitats. (C) 1998 The Fisheries Society of the British Isles.