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Characterizing the diversity of demographic strategies among species can inform research in topics such as trait syndromes, community stability, coexistence, and ecological succession. However, this diversity can depend on the spatial scale considered: at the landscape scale, species often form metapopulations, that is sets of local, sometimes short‐lived, populations, inhabiting discrete habitat patches. Metapopulation dynamics are most frequently analyzed in individual species or pairs of interacting species because of the large amount of data required for multiple species, and because species vary in their perceptions of what constitutes a favorable or unfavorable habitat. Here we evaluate, using a case study, whether a metapopulation model can be used to generate accurate estimates of demographic parameters and to describe the diversity of dynamics, responses to environment, and prospects of long‐term persistence in a guild of species inhabiting a common fragmented landscape. We applied this approach to a guild of 22 mollusk species that inhabit freshwater habitats on two islands of Guadeloupe, to compare metapopulation dynamics among species. We analyzed a 15‐year time series of occupancy records for 278 sites using a multistate occupancy model that estimated colonization and extinction rates as a function of site‐specific and year‐specific environmental covariates, then used model results to simulate future island metapopulation dynamics. Despite the diverse array of metapopulation trajectories—a mix of species with either stable, increasing, declining, or fluctuating metapopulations—and the inherent challenges associated with such data (e.g., imperfect detection, spatial and temporal heterogeneity), our model accurately captured among‐patch variation in suitability for many mollusk taxa. The dynamics of rare species or species with habitat preferences not fully captured by the retained set of covariates were less well described. For several species, we detected a negative correlation between extinction and colonization. This variation in habitat suitability created species‐specific extinction‐resistant pockets in the landscape. Our comparative analysis also revealed that species had distinct strategies for metapopulation dynamics, such as "fast‐turnover" species with both a high proportion of occupied sites and a high rate of site extinction in the landscape. [ABSTRACT FROM AUTHOR]

Biological invasions offer interesting situations for observing how novel interactions between closely related, formerly allopatric species may trigger phenotypic evolution in situ. Assuming that successful invaders are usually filtered to be competitively dominant, invasive and native species may follow different trajectories. Natives may evolve traits that minimize the negative impact of competition, while trait shifts in invasives should mostly reflect expansion dynamics, through selection for colonization ability and transiently enhanced mutation load at the colonization front. These ideas were tested through a large-scale common-garden experiment measuring life-history traits in two closely related snail species, one invasive and one native, co-occurring in a network of freshwater ponds in Guadeloupe. We looked for evidence of recent evolution by comparing uninvaded or recently invaded sites with long-invaded ones. The native species adopted a life history favoring rapid population growth (i.e., increased fecundity, earlier reproduction, and increased juvenile survival) that may increase its prospects of coexistence with the more competitive invader. We discuss why these effects are more likely to result from genetic change than from maternal effects. The invader exhibited slightly decreased overall performances in recently colonized sites, consistent with a moderate expansion load resulting from local founder effects. Our study highlights a rare example of rapid life-history evolution following invasion. [ABSTRACT FROM AUTHOR]

Inbreeding is expected to impair male and female reproductive performance, but little is known on how inbreeding depression varies between sexes and different levels of competition. We studied inbreeding depression in mating behavior and its reproductive consequences in a hermaphroditic freshwater snail and demonstrate that inbreeding depresses mating success in both sex functions. However, the magnitude of inbreeding depression does not differ between sex functions and is not affected by the opportunity for mate choice and male–male competition.Theoretical work predicts that the magnitude of inbreeding depression is particularly high in traits that are closely related to fitness. Despite the extensive work on inbreeding depression of male and female reproductive performance, relatively little is known on how inbreeding impairs male and female mating behavior. We studied inbreeding depression of male and female mating behavior in the simultaneously hermaphroditic freshwater snail Physa acuta to test 1) whether there is inbreeding depression of mating behavior, 2) whether the potential of mate competition and mate choice has an effect on the strength of inbreeding depression, 3) whether the magnitude of inbreeding depression differs between both sex functions, and 4) how inbreeding depression of mating behavior translates into inbreeding depression of reproductive success. For this, we compared the mating behavior between selfed (inbred) and outcrossed (outbred) focal snails in a series of mating trials, in which we manipulated experimentally the potential of mate competition and mate choice. Our results provide evidence for moderate inbreeding depression of the number of copulatory encounters, the number of copulations, and the total time spent mating in both sex functions. The magnitude of inbreeding depression did not differ between the levels of competition and between both sex functions. Finally, our results suggest that inbreeding depression of mating behavior only explains a small fraction of the observed inbreeding depression of reproductive success. We discuss the implications of these findings with respect to precopulatory sexual selection and sex-specific inbreeding depression. [ABSTRACT FROM PUBLISHER]

Quantifying metapopulation dynamics is a challenging task. Difficulties particularly arise in species that possess unobservable resistance forms that bias the estimation of colonization and persistence rates. Here, we develop a general multistate occupancy model that allows estimation of species persistence for both normal and resistant forms, even when the latter are not detectable. We apply this model to an 11-year data set on the tropical freshwater snail Drepanotrema depressissimum in a network of 229 ponds. These ponds frequently dry out, and the snails can persist by aestivating in the ground, where they are not detected. Our model adequately captures this feature because it infers a high persistence rate for the resistant form, while models ignoring aestivation tend to overestimate extinction and colonization. In addition, we find that, surprisingly, colonization and persistence are even higher in sites prone to desiccation and during years with low rainfall than in more humid sites and years, suggesting that D. depressissimum favors unstable sites where competitors are rare and where it can rely on aestivation to persist. Our model has the potential to provide valuable insights into the metapopulation dynamics of many species that otherwise could hardly be studied because of the existence of undetectable life forms. [ABSTRACT FROM AUTHOR]