Interaction between female mating preferences and predation may explain the maintenance of rare males in the pentamorphic fish Poecilia parae

Abstract

Variation in mating preferences coupled with selective predation may allow for the maintenance of alternative mating strategies. Males of the South American live‐bearing fish Poecilia parae fall in one of five discrete morphs: red, yellow, blue, stripe‐coloured tail (parae) and female mimic (immaculata). Field surveys indicate that the red and yellow morphs are the rarest and that their rarity is consistent across years. We explored the role of variable female mating preference and selective predation by visual predators in explaining the rarity of red and yellow males, and more generally, the maintenance of this extreme colour polymorphism. We presented wild‐caught P. parae females and Aequidens tetramerus, the most common cichlid predator, with the five male colour morphs in separate trials to determine mating and prey preferences, respectively. We found that a large proportion of females shared a strong preference for the rare carotenoid‐based red and yellow males, but a distinct group also preferred the blue and parae morphs. The cichlid predator strongly preferred red and yellow males as prey. Together, these results suggest that the interaction between premating sexual selection favouring and predation acting against the red and yellow morphs may explain their rarity in the wild. The trade‐off between sexual and natural selection, accompanied by variation in female mating preferences, may therefore facilitate the maintenance of the striking colour polymorphism in P. parae.

Ecology and seasonal variation of parasites in wild Aequidens tetramerus, a Cichlidae from the Amazon

“…This cichlid frequently inhabits areas with weak currents and over substrates covered with vegetative debris, and feeds primarily on insects, secondarily on plants, aquatic invertebrates and fishes (Santos et al 2004, Hurtado-Gonzales et al 2010. Parents take care of juveniles and are known to be very territorial fish (Hurtado-Gonzales et al 2010).…”

ASPECTS OF THE REPRODUCTIVE BIOLOGY OF<i> Aequidens tetramerus </i>(CICHLIDAE) IN VÁRZEA AREAS OF THE MIDDLE SOLIMÕES RIVER, BRAZILIAN AMAZON

“…Fertility is related to various factors, such as the size of the individuals, environmental conditions, and reproductive behaviour of the species (ARAÚJO, 2009). A. tetramerus exhibits parental care behaviour (KEENLEYSIDE, 1979;HURTADO-GONZALES et al, 2010;KULLANDER;FERRARIS JR, 2003). Fertility seems to be a parameter that is inversely proportional to the degree of parental care (LAGLER et al, 1977).…”

Variation in the Visual Habitat May Mediate the Maintenance of Color Polymorphism in a Poeciliid Fish

“…These morphs include: (i) immaculata , the smallest and drab-colored males that resemble juvenile females, (ii) parae , the largest males that exhibit a striped tail and black vertical body bars that intensify during social interactions, and the (iii) blue , (iv) red , and (v) yellow males with colorful body flanks and intermediate body size [34], [35], [36]. Drab immaculata males use a sneaker strategy to gain copulations with females [37].…”

“…Field and laboratory studies suggest that the male color polymorphism in P. parae is stable across time [34] and may be maintained by a complex balance between the opposing effects of sexual and natural selection [36]. Laboratory experiments that controlled for male-male competition and standardized the photic environment (i.e., Sun-Glo linear fluorescent bulbs, Hagen, MA; ∼25 µE s −1 m −2 mimicking natural, clear day light spectrum) revealed repeatable and variable female mating preferences for the colorful red, yellow and blue morphs.…”

“…Laboratory experiments that controlled for male-male competition and standardized the photic environment (i.e., Sun-Glo linear fluorescent bulbs, Hagen, MA; ∼25 µE s −1 m −2 mimicking natural, clear day light spectrum) revealed repeatable and variable female mating preferences for the colorful red, yellow and blue morphs. That is, most test females strongly preferred either red or yellow males but a few showed consistent preferences for blue males [36]. Likewise, Aequidens tetramerus , a common visual cichlid predator of P. parae , exhibited a visual bias for red and yellow males, suggesting that selective predation may offset the mating advantages of red and yellow males thus keeping them relatively rare in natural populations [36].…”