Wildfires shape ecosystems globally, yet little is known on their effects on wildlife distribution and spatial behaviour. We used bats as models to test the effects of fire on ecosystems because they ...are multi‐habitat specialists and feature ecological and life traits such as behavioural plasticity and longevity that make them able to respond to both short‐ and long‐term environmental changes. We aimed at testing the effects of a severe wildfire on a Mediterranean bat assemblage in terms of occupancy, activity and individual fitness. Here, we measure the effects of fire on activity levels and occupancy by a Mediterranean bat assemblage at the Vesuvius National Park, in Southern Italy, over 4 years, encompassing a year when a severe wildfire occurred. By comparing bat occurrence and activity at burnt versus unburnt sites with a Before‐After/Control‐Impact approach, we found that bat responses to wildfires are species specific and depend on the time elapsed since the fire. Species that rely more strongly on forest areas showed a strong short‐term adverse response in terms of occupancy and activity, while species adapted to open habitats showed no response 1 year after the wildfire. However, most species showed a general positive effect due to the passage of fire 2 years after its occurrence, probably because of vegetation regrowth. The wildfire event was also associated with reduced reproduction in at least one species, and to worse individual body conditions 1 year after the wildfire. Our results show that most bats in a Mediterranean ecosystem show resilience to the occurrence of fire, yet many species show negative short‐term responses by altering their spatial behaviour and decreasing their investment in reproduction. Future increases in fire occurrence and intensity due to climate change may alter bat assemblages and impair population viability in the long term, hampering the fundamental ecosystem services provided by structured bat communities.
We used bats as model organisms to assess the effects of a severe wildfire, and found that bat responses to wildfires are species‐specific and depend on the time elapsed since the fire. Forest species show a strong short‐term adverse response in terms of occupancy and activity, while species adapted to open habitats show no response, yet the wildfire also impaired reproduction in at least one of such species, and affected negatively its body condition 1 year after the wildfire.
Artificial illumination at night (ALAN) alters many aspects of animal behaviour. Commuting and foraging bats have been found to be affected by ALAN, but no study has yet addressed the impact of ...lighting on drinking activity, despite its critical importance for bats. We experimentally illuminated cattle troughs used by drinking bats at four forest sites in Italy, and compared drinking activity and foraging activity under lit and dark conditions. We predicted that (1) the number of bat species and drinking events will be lower under illumination and (2) forest bat species will be more affected than edge specialists. We recorded 2549 drinking events from 12 species or species groups, most of which decreased drinking activity under illumination. The effects of ALAN on drinking were stronger than on foraging. Forest species never drank when the light was on. Edge‐foraging species reduced drinking activity while also increasing foraging under lit conditions. We highlight a previously overlooked negative effect of ALAN on bats, whose implications may be locally catastrophic. Given the importance of water sites for both bat foraging and drinking, their illumination should be forbidden, appropriately mitigated or, if necessary, compensated for with the creation of alternative drinking sites.
We show that artificial illumination leads to a dramatic decrease in bat drinking activity. We found that lighting affects drinking behaviour more than foraging and that even species usually regarded as light‐tolerant exhibit adverse reactions to light when drinking. Illumination of drinking sites may therefore have considerably harmful consequences for bat conservation (Image courtesy of Jens Rydell).
Understanding the geographical distribution of phenotypically highly similar species (i.e. cryptic species) represents a challenge to biogeographers, due to the obvious difficulties in identifying ...such taxa without specific expertise. Besides, citizen science is increasingly emerging as a key approach for supporting biodiversity data collection, but remains hard to apply in the case of cryptic species. Here we aim to test the combination of community records and photography‐based quantitative methods, for assessing the distribution of cryptic taxa, by using two grasshopper species of the genus Aiolopus as models. To achieve these objectives, we first assess the reliability of photography‐based diagnostic criteria to differentiate between A. thalassinus and A. puissanti without ambiguity from correctly identified records, and then apply such criteria to geographical regions of potential range overlap between the two species, in order to clarify their respective distributions. By applying a multivariate classification approach based on ratio measurements taken from photographs, we provide a quantitative tool to successfully identify the two species, and disclose that A. puissanti widely occurs outside of its currently known range, and outline potential research avenues on the biogeography of these poorly studied species. Our results also point at how some types of cryptic species may be effectively identified by adopting a quantitative photography‐based approach, with applicability for clarifying species' distributions at wide scales by exploiting publicly available citizen‐science records. Our study thus, besides shedding light onto the biogeography and distributions of Aiolopus grasshoppers across the Mediterranean, represents an effective and repeatable framework to disentangle the distributions of poorly studied cryptic species.
We assessed the potential of photography‐based measurements in identifying green‐winged grasshoppers. By applying a multivariate classification approach based on ratio measurements taken from photographs, we provide a quantitative tool to successfully identify two closely resembling species from the genus Aiolopus, and disclose that the recently described A. puissanti widely occurs outside of its currently known range.
The replacement of natural habitats by urbanization and agricultural land reclamation is one of the main drivers of biodiversity loss. Among European habitat types, natural grasslands are ...particularly prone to anthropogenic pressures, being also recognized as conservation priorities within the Habitats Directive. Nonetheless, little is known on the relationship between grasslands, their conservation quality, and most animals' taxa that may rely upon them. Here we focus on the role of Mediterranean dry grasslands protected by the EU legislation in sustaining bat populations, setting our study in the biodiversity hotspot of Mediterranean Italy. By conducting acoustic surveillance at 48 sites within a protected area devoted to conserve natural and semi-natural grasslands, we found that all the bat species found in the area are regular exploiters of such open environments. Grassland conservation quality, in terms of extent of high-diversity protected habitats, was the key factor shaping the use of grasslands by bats of all the considered guilds, together with several terrain and landscape features, which showed more guild-specific effects. Moreover, our results indicate that bat assemblages are functionally shifted along an ecological gradient from highly modified to well-conserved grassland sites, indicating a prevalence of opportunistic taxa in the former, and higher abundance of species of conservation concern in the latter. Overall, we demonstrate that the effects of EU-listed habitats may extend also onto bats in the case of Mediterranean dry grasslands, highlighting the importance of preserving such habitats as a tool for conserving highly mobile species.
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•We investigated ecological drivers of bat activity in a Mediterranean grassland ecosystem.•We focused on the effects of landscape composition and of protected habitats on bats.•Landscape composition and terrain factors shaped activity of bats from all guilds.•Bat assemblages significantly shifted from natural to anthropogenic grasslands.•EU-listed high-diversity grasslands sustain bats by boosting activity levels.
Islands host high numbers of endemic species, and the latter are especially exposed to human-driven habitat alteration because their population size is constrained by the limited space and resources ...found in insular systems. Extreme events linked with climate change and direct anthropogenic stressors may synergistically affect endemic species, and even push them to the brink of extinction. Bats include many insular endemics whose life traits make them excellent candidates to test the effects of both climate-change driven events and direct human disturbance. The Mediterranean island of Sardinia is home to the endemic long-eared bat
Plecotus sardus
. Within the island, this recently described species is restricted to a limited range where suitable habitat is present. This makes the species extremely vulnerable to human action. Here we use
Plecotus sardus
as a model to assess the response of insular endemic bats to climate change and human disturbance, exploring demographic trends across two decades. Overall, roost count data for all known reproductive sites showed a steep (-63.4% between 2003 and 2020) population decline, so that the current estimated population size is only 36.5% of that observed in 2003. Colony growth rates are strongly affected by recurring wildfires around reproductive sites, summer precipitation and temperature extremes, pointing to climate change as a primary threat to the species along with direct human interference. Such anthropogenic pressures may therefore rapidly expose island endemic bats to a high extinction risk. Based on our analysis,
Plecotus sardus
is among the most threatened mammals, and likely the rarest bat species, in Europe. Thus, we urge that (1) similar assessments are conducted on other insular endemic bats in Mediterranean Europe, (2) IUCN Redlist categories are revised according to new analyses, and (3) recovery action plans are immediately developed and implemented to revert the current population trends.
•Human activities and the presence of domestic predators are primary stressors to urban wildlife.•Disturbance outside the roost disrupts clusters of roosting bats in buildings.•People in proximity to ...roost entrance exert antipredatory responses in emerging bats.•Domestic cats enter urban bat roosts and alter colony behaviour besides preying upon bats.
Proximity to humans is a primary stressor for wildlife, especially in urban habitats where frequent disturbance may occur. Several bat species often roost in buildings but while the effects of disturbance inside the roost are well documented, little is known about those occurring in the proximity of roosts. We tested the effects of anthropogenic stressors on bats by monitoring reactions to disturbance in a colony of greater horseshoe bats (Rhinolophus ferrumequinum). We assessed disturbance by recording and quantifying the presence of people, domestic cats and noise sources near the roost. Disturbance outside the roost caused the disruption of roosting clusters; when cats entered the roost, bats decreased indoor flight activity. Emergence timing was delayed when people were close to the roost exit, and the delay increased along with the number of people. The occurrence of a cat increased the degree of group clustering during emergence. Cats entered the roost especially when young bats were present, and bat remains occurred in 30% of the cat scats we examined. We show that the occurence of human activities near roosts and free-ranging domestic cats are important albeit overlooked sources of disturbance.
The genus Hystrix includes eight species of porcupines distributed in Eurasia and Africa, across a broad latitudinal gradient. Our aim was to assess whether porcupine skulls: (1) allow for a reliable ...interspecific distinction; (2) change in size proportionally with body size; (3) follow the Bergmann's rule. We measured 235 Hystrix skulls from museums and private collections. We tested for differences in skull size and we assessed whether variability in skull shape allows species recognition through a multivariate approach. All Hystrix species considered could be reliably identified by skull shape. Skull size was correlated with body size and species differed in skull shape and size, with skulls of Hystrix javanica and Hystrix africaeaustralis being respectively the smallest and the largest ones. Within Hystrix cristata, the Mediterranean and the sub‐Saharan clades differed for both skull size and shape. Using skull size, we could distinguish among African, mainland Italian and Sicilian populations. Skull size of this species decreased in size for increasing latitude values, contrary to prediction by the Bergmann's rule. Such latitudinal pattern may depend on the adaption of H. cristata to Equatorial African conditions, where the species evolved. In Italy (where H. cristata was introduced in the VI Century AD) and in North Africa, a smaller body size may be due to the local climate, or to a ‘founder effect’.
In our work, we aimed to assess whether porcupine skulls fit the Bergmann’s rule. We measured 235 Hystrix skulls of 5 species from museums and private collections. The opposite pattern of the Bergmann’s rule was observed in Hystrix cristata may be due to the fact that this species evolved in Equatorial Africa. In Italy (where introduced) and in North Africa as well, a smaller body‐size would occur because of unsuitable climates or as a result of the founder effect.
Sexual dichromatism in animals is usually associated with mating displays and is linked to strong sexual selection. Among amphibians, it has mostly been reported in anurans and only in a few ...caudates. Here, we investigated sexual dichromatism in the only two extant species of the genus Salamandrina, testing for its possible role in intraspecific communication during the mating rituals of these terrestrially mating salamanders. In both S. terdigitata and S. perspicillata, we highlighted that males have more conspicuous ventral colourations, yet this is limited to the throat region, namely featuring rounder, larger and brighter gular white patches than females. We also described a new mating ritual behaviour performed by male S. perspicillata, that is, a stereotyped throat hyperextension, that enhances the visibility of the dimorphic colouration of the gular region of males, presumably representing a visual cue directed to females. We thereby discuss the potential role of sexual dichromatism in sexual selection and the evolutionary history of the genus Salamandrina.
Spectacled salamanders feature sexual dichromatism, with males having more conspicuous colouration on their throats. Such colouration is likely to play a role in courtship rituals and intraspecific communication during stereotyped displays.
Competition for critical resources is one of the key mechanisms through which invasive species impact on native communities. Among birds, the widely introduced ring‐necked parakeet Psittacula krameri ...locally affects cavity‐nesting communities through competition for suitable tree cavities, although it remains unclear to what extent such competition translates into population declines of native species. Here, we studied the potential for nest site competition between ring‐necked parakeets and the native scops owl Otus scops, a small nocturnal migratory raptor, by comparing the spatial distribution of the nest site locations of the raptor before (2002) and after (2015) the parakeet invasion. Pre‐invasion nesting sites of scops owls (2002) strongly coincided with those selected by ring‐necked parakeets, but although both parakeet and scops owl populations increased during the study period, this was no longer true for 2015. Ring‐necked parakeets took over several cavities formerly occupied by scops owls, and land‐use data suggest that because of the higher overall breeding densities in 2015, scops owls were forced to occupy suboptimal breeding habitats to minimize nest site competition with invasive parakeets. Ring‐necked parakeets start breeding early in the season, a behaviour enabling them to secure the best nest sites first, before the owls return from their wintering grounds. Our study highlights that locally observed competition not necessarily impacts on population dynamics of competing species and thus warns against uncritical extrapolation of smaller scale studies for assessing invasive species risks at larger spatial scales. Nonetheless, given the increasing number of studies demonstrating its competitive capacities, monitoring of ring‐necked parakeet populations is prudent and mitigation measures (such as mounting of man‐made nest‐boxes, which are used by scops owls, but not by parakeets) may be justified when the parakeets are likely to invade areas harbouring cavity‐nesters of conservation concern.
Before the invasion of ring‐necked parakeets, scops owls occupied a number of breeding sites located within urban parks and green areas within the city of Follonica (Southern Tuscany). After the invasion, ring‐necked parakeets took over several cavities formerly occupied by owls, forcing them to breed in suboptimal areas to avoid competition with alien parrots. Locally observed competition may occur without affecting population size of native species.
Bats show pronounced and often‐adverse reactions to artificial illumination at night (ALAN) when commuting, roosting or foraging. ALAN also affects bat drinking activity, at least when lighting ...occurs over short intervals. We tested whether continuous illumination of drinking sites over 4‐h periods would lead bats to tolerate ALAN and resume drinking in the course of the night. We conducted our experiments in forest (Italy) and desert (Israel) sites to test whether in the latter habitat, where water is scarce, a greater motivation to drink might lead to less adverse bat reactions. We recorded 6853 drinking buzzes and 1647 feeding buzzes from 17 species and one species group. In the forest sites, species that hunt in open spaces or along forest edges showed little (P. pipistrellus and H. savii) or no (P. kuhlii and N. leisleri) drinking activity decrease, while those associated with forest interiors (Barbastella barbastellus, Plecotus auritus and bats in the genus Myotis) exhibited a strong negative response. In the desert sites, all studied species reduced drinking activity, yet in the desert populations of P. kuhlii we recorded stronger adverse reactions only far from human settlements. The harsh reactions that the desert bat species showed towards ALAN rule out any effect of a greater motivation to drink. Illumination had no effect on foraging by most species, except in the forest sites, where Pipistrellus kuhlii and Nyctalus leisleri increased foraging when the light was on, and in the desert sites, where Hypsugo bodenheimeri decreased foraging in such situations. The progressive human encroachment that is taking place in many world regions on both forests and especially deserts, where few sites for drinking are available, may jeopardize bat populations also through increased exposure to ALAN.
We tested reactions of drinking bats to continuous illumination of drinking sites over 4‐h periods in forest (Italy) and desert (Israel) sites and hypothesized that in the latter habitat, where water is scarce, a greater motivation to drink might lead to less adverse responses. We found that artificial illumination seriously affected bat drinking behaviour, especially that of forest specialists and desert species. The increasing human encroachment that is taking place in many world regions on both forests and especially deserts, where few drinking sites are available, may jeopardize bat populations also through increased exposure to artificial lighting.
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