ABSTRACT: The combined acoustic activity of soniferous organisms living in benthic habitats produces habitat-specific soundscapes, which are predicted to influence fish and invertebrate lar- val behavior during the settlement process. Not every sound will have the amplitude and fre- quency characteristics relative to hearing sensitivity to be used as an acoustic cue, thus the cuescape is a subset of the soundscape. These sounds vary through space and time, and little is known about how this variability could influence their role in settlement. We recorded the sound- scapes of 4 coral reefs in Caribbean Panama for 6 wk and conservatively identified the sounds most likely to compose the cuescapes used by larval fishes. While these sites represented the vari- ation in reef condition across the study area, we observed the same 4 dominant taxa groups emerge as the most likely producers of acoustic cues. These results were consistent across both time and space when compared to short-term recordings taken at these 4 reefs and at an addi- tional 11 sites 2 yr prior. Next, we used an individual-based model to test the relationship between settlement success and the natural spatiotemporal variability we observed in these potential cues. Temporal variation in the sounds resulted in variation in settlement success; however, even short- range, intermittent cues improved the likelihood of settlement. Overall, we observed similar acoustic cuescapes across reefs that varied in condition, suggesting that cuescapes can be resilient to some forms of reef degradation by retaining sounds potentially useful to larval fishes for both navigation and habitat selection.

KEY WORDS: Coral reef · Soundscape · Larval fish · Larval settlement · Acoustics · Modeling · Cues · Fish behavior

Island systems have long played a central role in the development of ecology and evolutionary biology. However, while many empirical studies suggest species differ in vital biogeographic rates, such as dispersal abilities, quantitative methods have had difficulty incorporating such differences into analyses of whole-assemblages. In particular, differences in dispersal abilities among species can cause variation in the spatial clustering and localization of species distributions. Here, we develop a single, hierarchical Bayes, assemblage-wide model of 252 bird species distributions on the islands of Northern Melanesia and use it to investigate a) whether dispersal limitation structures bird assemblages across the archipelago, b) whether species differ in dispersal ability, and c) test the hypothesis that wing aspect ratio, a trait linked to flight efficiency, predicts differences inferred by the model. Consistent with island biogeographic theory, we found that individual species were more likely to occur on islands with greater area, and on islands near to other islands where the species also occurred. However, species showed wide variation in the importance and spatial scale of these clustering effects. The importance of clustering in distributions was greater for species with low wing aspect ratios, and the spatial scale of clustering was also smaller for low aspect ratio species. These findings suggest that the spatial configuration of islands interacts with species dispersal ability to affect contemporary distributions, and that these species differences are detectable in occurrence patterns. More generally, our study demonstrates a quantitative, hierarchical approach that can be used to model the influence of dispersal heterogeneity in diverse assemblages and test hypotheses for how traits drive dispersal differences, providing a framework for deconstructing ecological assemblages and their drivers.This article is protected by copyright. All rights reserved.

As global warming has lengthened the active seasons of many species, we need a framework for predicting how advances in phenology shape the life history and the resulting fitness of organisms. Using an individual-based model, we show how warming differently affects annual cycles of development, growth, reproduction and activity in a group of North American lizards. Populations in cold regions can grow and reproduce more when warming lengthens their active season. However, future warming of currently warm regions advances the reproductive season but reduces the survival of embryos and juveniles. Hence, stressful temperatures during summer can offset predicted gains from extended growth seasons and select for lizards that reproduce after the warm summer months. Understanding these cascading effects of climate change may be crucial to predict shifts in the life history and demography of species.

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