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Parasites alter many traits of their hosts. In particular, parasites known as “manipulative” may increase their probability of transmission by inducing phenotypic alterations in their intermediate hosts. Although parasitic-induced alterations can modify species’ ecological roles, the proximate factors modulating this phenomenon remain poorly known. As temperature is known to affect host–parasite associations, understanding its precise impact has become a major challenge in a context of global warming. Gammarids are ecologically important freshwater crustaceans and serve as intermediate hosts for several acanthocephalan species. These parasites induce multiple effects on gammarids, including alterations of their behavior, ultimately leading to modifications in their functional role. Here, experimental infections were used to assess the effect of two temperatures on several traits of the association between Gammarus pulex and its acanthocephalan parasite Pomphorhynchus laevis . Elevated temperature affected hosts and parasites in multiple ways (decreased host survival, increased gammarids activity, faster parasites development and proboscis eversion). However, behavioral manipulation was unaffected by temperature. These results suggest that predicted change in temperature may have little consequences on the trophic transmission of parasites through changes in manipulation, although it may modify it through increased infection success and faster parasites development.

Although urbanization is a major threat to biodiversity, some native species have managed to persist in urban areas. Populations of such species often show phenotypic differences with their rural counterparts. A crucial question is whether such differences result from different selection regimes between habitats. As previous studies showed that suburban and forest populations of Anolis homolechis differ in both body size and sex ratio, we tested the effect of urbanization on adult survival in those populations based on a long-term capture–marking–recapture survey and replicated design. We assessed the evidence for directional and stabilizing selection on size in two suburban and two forest populations by modeling apparent adult survival and recapture probability separately. Adult survival did not differ between habitat types. In addition, there was no evidence for size-related differential selection on adult survival between habitats. However, irrespective of habitat, we found significant stabilizing selection on female size, whereas male survival was independent of size. Overall, sex had a significant effect on survival independent of habitat type (monthly survival probability: 0.80 for males vs. up to 0.89 for females of optimal size). We discuss our results in relation to the potential mechanisms involved in the observed phenotypic differentiation of A. homolechis and other lizard species in areas transformed by urbanization.

Early reporting of the introduction and establishment of exotic species is of paramount importance for successful management. Here, we report the introduction and rapid spread of the Bare-eyed Pigeon, Patagioenas corensis, on the binational island of Saint-Martin, the West Indies. This range-restricted species naturally occurs in arid coastal areas of Columbia and Venezuela and nearby islands. Its introduction on Saint-Martin represents an expansion of about 1000 km beyond its established native range. Using observations recorded in eBird and results from a recent field survey, we show that since its introduction, most probably between late 2012 and early 2013, the species has expanded fast in Saint-Martin and has recently broadened its habitat to include anthropized, built areas. The expansion of Bare-eyed Pigeon on Saint-Martin and the neighboring Leeward Islands, possibly facilitated by climate change in the future, could be a threat to both native columbid species and other bird species through competition for resources. We therefore recommend that local authorities and stakeholders rapidly eradicate the species or at least prevent its further spread on Saint-Martin, possibly though listing it as a game species, while it is still possible to do so.

The white-crowned Pigeon (WCPi), Patagioenas leucocephala, and the scaly-naped Pigeon (SNPi), P squamosa, are two Caribbean endemic species of patrimonial and cynegetic interest. Although both species are under the threat of habitat destruction and hunting pressure, population trends remain undocumented in a large part of their geographical range. Here, we used both the “auditory and visual” and “call-broadcast” census methods to assess the occurrence and relative abundance of both species in Guadeloupe (French West Indies). The call-broadcast method was found to be more efficient as it reduced the problem of “false absence” while increasing the probability of detection. Results from our surveys showed that both WCPis and SNPis were at low density and showed complete habitat segregation. SNPis were only encountered in rainforest, whereas WCPis could be observed at count stations located in dry and swamp forests, mangroves, agricultural lands and wet meadows. We recommend the use of the call-broadcast method for monitoring the two species on islands where they occur at low density, under which conditions distance sampling may be poorly reliable. The general relevance of the call-broadcast method to other species of pigeons and doves deserves further attention, especially to document population trends in elusive game species of conservation interest.

The measurement of female mating preferences is central to the study of the evolution of male ornaments. Although several different methods have been developed to assess sexual preference in some standardized way, the most commonly used procedure consists of recording female spatial association with different males presented simultaneously. Sexual preference is then inferred from time spent in front of each male. However, the extent to which the measurement of female mate-choice is related to exploration tendencies has not been addressed so far. In the present study we assessed the influence of variation in exploration tendencies, a trait closely associated to global personality, on the measurement of female mating preference in the zebra finch (Taeniopygia guttata) using the widely used four-chamber choice-apparatus. The number of movements performed within both exploration and mate-choice apparatus was consistent within and across the two contexts. In addition, personality explained variation in selectivity, preference strength and consistency. High-exploratory females showed lower selectivity, lower preference scores and displayed more consistent preference scores. Our results suggest that variation in personality may affect the measurement of female mating preference and may contribute to explain existing inconsistencies across studies.

Although forest-dependent, tropical island endemic birds are particularly at risk of extinction, they remain largely understudied. In this context, we assessed the spatial occupancy, local abundance, and diel activity in three forest columbid species of hunting interest, the Ruddy Quail-Dove (RQD), Geotrygon montana; the Bridled Quail-Dove (BQD), Geotrygon mystacea; and the Zenaida Dove (ZD), Zenaida aurita, in Guadeloupe (French West Indies), using 5 camera-traps over 14 days on 24 survey stations, resulting in 1680 trap days. The number of observed RQD was too small to allow for a statistical comparison between habitats. BQD were more frequently observed at camera-trap stations that were dominated by tropical rainforest than those that were dominated by flooded forest. Conversely, ZD were more frequently observed at stations that were dominated by flooded forest and dry forest than at those that were dominated by tropical rainforest. High temperatures negatively affected the abundance of BQD, while the abundance of ZD was significantly lower in tropical rainforests compared to dry and flooded forests and tended to increase with canopy openness. The three species were diurnal. BQD significantly positively co-occurred spatially and temporally with small Indian mongooses, Urva auropunctata, whereas the temporal and spatial distribution of ZD overlapped significantly with that of domestic dogs, Canis familiaris, and domestic cats, Felis catus. Our results provide firm evidence that RQD remains scarce and is largely outnumbered by BQD in Guadeloupe which is in contrast with has been reported for other Caribbean islands.

Although growing urbanization has direct negative consequences for local biodiversity, several native species have been observed maintaining populations in urban environments. Understanding which factors influence the ability of native species to persist in urban environments is crucial, both for the study of biological adaptation and of urban planning. The quantification of the proportion of juvenile individuals can be a good proxy for assessing the long-term persistence of urban populations. We present comparative data about spatial and temporal variations in the age-class structure in two suburban and two forest populations of the Cuban endemic lizard Anolis homolechis, obtained during a 20-month survey. We found a four-fold lower proportion of juveniles in the suburban habitat compared to the forest one. There was, however, no evidence for differential female fecundity between the two habitats, as assessed by the proportion of gravid females. Conversely, the rate of tail autotomy (an antipredator behavior) was significantly higher in the suburban juveniles compared to the forest ones, possibly reflecting a higher exposure to predators and, particularly, inter- and intraspecific cannibalism. However, tail loss at initial capture or habitat type had no effect on the probability of recapture of juveniles. We discuss the potential causes and consequences of a modified age-class structure in urbanized environments.

Sex-determination is of particular importance in avian ecology and conservation. However, many bird species show no conspicuous sexual dimorphism, such as the La Selle Thrush, Turdus swalesi, a vulnerable species endemic to Hispaniola. We captured individuals in southeastern Haiti, in 2019–2022. For each one, we collected contour feathers or blood samples for molecular sex identification based on the CHD-1 gene. In addition, we took body measurements of several captured individuals and recorded their weight. Out of a total of 65 birds, 45 were identified as males and 20 as females, indicative of a significantly male-biased sex ratio. However, analyses of first captures showed that the sex ratio at our study site was male-biased only outside of the breeding season, suggesting that females may disperse at that time while males remain on their territories. Sexual dimorphism was limited to wing chord length and tail length, with males being larger than females. Tail length was the best predictor of sex in a logistic regression model and correctly classified about 80% of individuals as male or female. We discuss our results in relation to previous studies of sex ratio and sexual dimorphism in turdid species and address their relevance for the conservation of avian species in one of the major protected forest areas in Haiti.

Urbanization transforms natural ecosystems into novel habitats, which can result in negative consequences for biodiversity. Therefore, it is important to understand the mechanisms of maintenance of native species in urbanized environments, including behavior—which can act as a fast response to rapid environmental changes. We compared some behavioral traits between two suburban and two forest populations of Anolis homolechis. Direct observations of 779 individuals revealed that perch height was positively influenced by body size, but not by sex. Suburban individuals perched higher than forest ones, and even more so in the afternoon compared to the morning; a behavior that was not observed in forests populations. These differences might be due to a change from foraging activities in the morning to vigilance, display, and/or thermoregulation in the afternoon, promoted by suburban habitat conditions (e.g., higher predator abundance, open habitat structure, and urban heat). Video recordings of 81 focal individuals showed that males were more active than females (i.e., spending less time in stationary behavior and having a higher display rate), with no significant effect of habitat type. As some of our results diverge from previous studies on invasive anoles, we recommend extending comparative studies of urban and non-urban populations to other native Anolis.

A crucial assumption underlying most models of sexual selection is that sexual advertisements honestly reflect the phenotypic and/or genetic quality of their bearers. Faivre et al show that experimental activation of the immune system is rapidly mirrored in the expression of a carotenoid-based secondary sexual trait in male balckbirds.