Breeding behaviour and mating success ofPhyllomedusa rohdei(Anura, Hylidae) in south‐eastern Brazil

Show me you care: female mate choice based on egg attendance rather than male or territorial traits

Female mate choice is often based on male traits, including signals or behaviors, and/or the quality of a male’s territory. In species with obligate paternal care, where care directly affects offspring survival, females may also base their mate choices on the quality of a sire’s care. Here, we quantified male reproductive success in a natural population of the glass frog Hyalinobatrachium cappellei, a species with male parental care, to determine the influence of territory quality, male traits, and paternal care behaviors on female mate choice. We found that attending males have a higher chance of gaining new clutches than nonattending males. Our results indicate that females do not select males based only on body condition, calling persistence, or territory traits. Instead, our findings support the hypothesis that females choose males based on care status. Indeed, males already attending a clutch were 70% more likely to obtain another clutch, and the time to acquire an additional clutch was significantly shorter. We also found that males adjust their parental care effort in response to genetic relatedness by caring only for their own offspring; however, remaining close to unrelated clutches serves as a strategy to attract females and increase chances of successful mating. Thus, males that establish territories that already contain clutches benefit from the signal eggs provide to females.

Temporal migration patterns and mating tactics influence size-assortative mating in Rana temporaria

Assortative mating is a common pattern in sexually reproducing species, but the mechanisms leading to assortment remain poorly understood. By using the European common frog (Rana temporaria) as a model, we aim to understand the mechanisms leading to size-assortative mating in amphibians. With data from natural populations collected over several years, we first show a consistent pattern of size-assortative mating across our 2 study populations. We subsequently ask if assortative mating may be explained by mate availability due to temporal segregation of migrating individuals with specific sizes. With additional experiments, we finally assess whether size-assortative mating is adaptive, i.e. influenced by mating competition among males, or by reduced fertilization in size-mismatched pairs. We find that size-assortative mating is in accordance with differences in mate availability during migration, where larger individuals of both sexes reach breeding ponds earlier than smaller individuals. We observe an indiscriminate mate choice behavior of small males and an advantage of larger males pairing with females during scramble competition. The tactic of small males, to be faster and less discriminative than large males, may increase their chances to get access to females. Experimental tests indicate that the fertilization success is not affected by size assortment. However, since female fecundity is highly correlated with body size, males preferring larger females should maximize their number of offspring. Therefore, we conclude that in this frog species mate choice is more complex than formerly believed.

Low reproductive skew despite high male-biased operational sex ratio in a glass frog with paternal care

BACKGROUND

Reproductive skew, the uneven distribution of reproductive success among individuals, is a common feature of many animal populations. Several scenarios have been proposed to favour either high or low levels of reproductive skew. Particularly a male-biased operational sex ratio and the asynchronous arrival of females is expected to cause high variation in reproductive success among males. Recently it has been suggested that the type of benefits provided by males (fixed vs. dilutable) could also strongly impact individual mating patterns, and thereby affecting reproductive skew. We tested this hypothesis in Hyalinobatrachium valerioi, a Neotropical glass frog with prolonged breeding and paternal care.

RESULTS

We monitored and genetically sampled a natural population in southwestern Costa Rica during the breeding season in 2012 and performed parentage analysis of adult frogs and tadpoles to investigate individual mating frequencies, possible mating preferences, and estimate reproductive skew in males and females. We identified a polygamous mating system, where high proportions of males (69 %) and females (94 %) reproduced successfully. The variance in male mating success could largely be attributed to differences in time spent calling at the reproductive site, but not to body size or relatedness. Female H. valerioi were not choosy and mated indiscriminately with available males.

CONCLUSIONS

Our findings support the hypothesis that dilutable male benefits - such as parental care - can favour female polyandry and maintain low levels of reproductive skew among males within a population, even in the presence of direct male-male competition and a highly male-biased operational sex ratio. We hypothesize that low male reproductive skew might be a general characteristic in prolonged breeders with paternal care.

Distribuição espacial e sazonal de anfíbios em quatro poças na região serrana do Espírito Santo, sudeste do Brasil: influência de corredores florestais

Este estudo avaliou a composição da anurofauna, bem como a distribuição espacial e temporal das espécies em quatro poças permanentes em uma região montanhosa do Espírito Santo, sudeste do Brasil. Duas dessas poças são conectadas a fragmentos florestais por corredores florestais e as outras duas poças são circundadas por plantação de eucalipto e habitação humana. Foram registradas 22 espécies, incluídas em cinco famílias, entre dezembro de 2003 a novembro de 2004. Hylidae foi a mais rica e abundante, apresentando elevada sobreposição espacial. Nove espécies foram coletadas em vegetação abaixo de 0,60 m, sendo o sítio de vocalização mais utilizado. Riqueza de espécies e abundância foram maiores em meses chuvosos. Poças com corredores abrigaram maior riqueza de espécies. Adicionalmente quatorze espécies foram exclusivamente encontradas nessas poças. A estrutura da comunidade de anuros em poças permanentes nessa paisagem fragmentada é aparentemente determinada pela presença ou ausência de corredores florestais conectando fragmentos em topos de morro às poças d'água ocorrentes ao longo dos vales.