Transition to organic farming negatively affects bat activity

1. The effectiveness of organic farming on biodiversity has been widely documented especially for plants, arthropods and birds; however, the effects of the transition period required to become an organic farm on wildlife remain poorly understood.2. We assessed the effects of organic farming on insectivorous bats in citrus orchards in the Republic of Cyprus employing two matched designs (conventional vs. 3-year organic-transitional and conventional vs. organic-certified) and a third unmatched design (3-year organic-transitional vs. organic-certified). We specifically investigated whether the transition period prior to full organic certification influenced bat activity with a special focus on any moderation effects from surrounding semi-natural areas.3. The activity of three (Pipistrellus kuhlii, Hypsugo savii and Miniopterus schreibersii) of four bat species was significantly lower in farms undergoing the transitional period than in conventional farms, and P. kuhlii and H. savii were significantly less active in organic transitional farming systems that in organic-certified ones. Furthermore, the activity of the most dominant species (P. kuhlii) was significantly higher on organic than transitional and conventional citrus orchards, thus suggesting a time-lag effect. Landscape complexity measured as the amount of semi-natural areas did not moderate the effects of farming system for any study species.4. Synthesis and application. The transition to organic farming had persistent detrimental effects on bats and potentially on the pest suppression services they provide. Future agri-environmental policy should consider the transition period and implement measures to mitigate any negative effects on biodiversity, alongside promoting asynchronous transition of nearby farms. Our findings further highlight the crucial need to consider the time since transition to organic farming when assessing potential benefits of organic management on biodiversity

Transition to organic farming negatively affects bat activity

The effectiveness of organic farming on biodiversity has been widely documented especially for plants, arthropods and birds; however, the effects of the transition period required to become an organic farm on wildlife remain poorly understood. We assessed the effects of organic farming on insectivorous bats in citrus orchards in the Republic of Cyprus employing two matched designs (conventional vs. 3-year organic-transitional and conventional vs. organic-certified) and a third unmatched design (3-year organic-transitional vs. organic-certified). We specifically investigated whether the transition period prior to full organic certification influenced bat activity with a special focus on any moderation effects from surrounding semi-natural areas. The activity of three (Pipistrellus kuhlii, Hypsugo savii and Miniopterus schreibersii) of four bat species was significantly lower in farms undergoing the transitional period than in conventional farms, and P. kuhlii and H. savii were significantly less active in organic transitional farming systems that in organic-certified ones. Furthermore, the activity of the most dominant species (P. kuhlii) was significantly higher on organic than transitional and conventional citrus orchards, thus suggesting a time-lag effect. Landscape complexity measured as the amount of semi-natural areas did not moderate the effects of farming system for any study species. Synthesis and application. The transition to organic farming had persistent detrimental effects on bats and potentially on the pest suppression services they provide. Future agri-environmental policy should consider the transition period and implement measures to mitigate any negative effects on biodiversity, alongside promoting asynchronous transition of nearby farms. Our findings further highlight the crucial need to consider the time since transition to organic farming when assessing potential benefits of organic management on biodiversity

Tree size, microhabitat diversity and landscape structure determine the value of isolated trees for bats in farmland

Isolated trees are increasingly recognised as playing a vital role in supporting biodiversity in agricultural landscapes, yet their occurrence has declined substantially in recent decades. Most bats in Europe are tree-dependent species that rely on woody elements in order to persist in farmlands. However, isolated trees are rarely considered in conservation programs and landscape planning. Further investigations are therefore urgently required to identify which trees – based on both their intrinsic characteristics and their location in the landscape – are particularly important for bats. We acoustically surveyed 57 isolated trees for bats to determine the relative and interactive effects of size, tree-related microhabitat (TreM) diversity and surrounding landscape context on bat activity. Tall trees with large diameter at breast height and crown area positively influenced the activity of Pipistrellus pipistrellus and small Myotis bats (Myotis spp.) while smaller and thinner trees favoured M. myotis activity. The diversity of TreMs that can be used as roosts had a positive effect on (i) Barbastella barbastellus activity only when trees were relatively close (10% within 100 radius scale). The potential benefits of isolated trees for bats result from ecological mechanisms operating at both tree and landscape scales, underlining the crucial need for implementing a multi-scale approach in conservation programs. Maintaining the largest and most TreM-diversified trees located in the most heterogeneous agricultural landscapes will provide the greatest benefits

Sexual segregation occurs in bats within fragmented remnant woodlands in an agricultural landscape

Abstract: Species‐specific responses to landscape configuration and landscape composition have been studied extensively. However, little work has been done to compare intraspecific differences in habitat preferences. Bats have potential as good bioindicator taxa in woodland habitats. Therefore, studying sex differences in responses to woodland and the wider landscape can allow us to gain insight into the relative importance of these habitats for both bats and other taxa. In this study, we aimed to test the predictions that (i) habitat type and connectivity will influence the probability of recording female bats in woodlands and (ii) sex differences in response to habitat type and connectivity will be species‐specific. Bat capture data was collected in 206 woodlands over 3 years in England. The probability of detecting females relative to males was modeled in response to a range of woodland characteristics and landscape metrics for six bat species. We recorded sex differences in responses to landscape features in three species. We found a higher probability of capturing female Myotis nattereri in woodlands that were surrounded by a higher proportion of improved grasslands, whereas female Myotis mystacinus were less likely to be recorded in woodlands surrounded by semi‐natural vegetation. Female Plecotus auritus were more likely to be recorded in isolated woodlands with less connectivity to other woodlands and where agriculture dominated the surrounding landscape. Our findings indicate that sexual segregation occurs across several UK bat species in response to landscape connectivity and composition. Sexual segregation in response to landscape characteristics in bats should therefore be an important consideration in the management of fragmented agricultural landscapes

Moths Consumed by the Barbastelle Barbastella barbastellus Require Larval Host Plants that Occur within the Bat's Foraging Habitats

Loss of foraging habitat and reductions in insect prey are key factors responsible for declines in bat populations. Identifying important bat foraging habitats and the ecological requirements and conservation status of prey provides evidence for appropriately targeted conservation management strategies. We examined the foraging habits of the barbastelle, Barbastella barbastellus, at the northern edge of its European range using a combination of radio tracking, to determine home range use and habitat selection, and DNA metabarcoding, to identify prey items consumed. Riparian vegetation and broadleaved woodland were the habitat types most strongly selected by foraging bats. Hedgerows within pastoral habitats were also important foraging features within the landscape. We identified 120 different prey items within faecal pellets, the majority of which were moths (97.5%). The large majority (97%) of prey items consumed have larval stages dependent on host plants that are typically found within habitats selected by foraging B. barbastellus. Almost half of all moth prey species identified have undergone considerable population declines in recent decades. We present the most comprehensive list to date of prey consumed by B. barbastellus and provide evidence that conservation management policies should target the protection and enhancement of key B. barbastellus foraging habitats within a 6.5 km sustenance zone around maternity roost sites. Riparian habitat, broadleaved woodland and linear landscape features such as hedgerows should be managed to improve their value to foraging B. barbastellus as well as the developmental stages of their preferred moth prey

Containment measures

OBSOLETE (project finished) - Description of containment measures during COVID'19 lockdown, in the context of SIlent Cities project. Please request access to Silent Cities if neede

Archived - General Information (DO NOT USE)

DO NOT USE - The goal of this component was to document the data collection process of the Silent Cities Dataset. This component is just left for archive