Horizon scanning for invasive alien species with the potential to threaten biodiversity and human health on a Mediterranean island

© 2019, The Author(s). Invasive alien species (IAS) are one of the major drivers of change that can negatively affect biodiversity, ecosystem functions and services and human health; islands are particularly vulnerable to biological invasions. Horizon scanning can lead to prioritisation of IAS to inform decision-making and action; its scale and scope can vary depending on the need. We focussed on IAS likely to arrive, establish and affect biodiversity and human health on the Mediterranean island of Cyprus. The scope of the horizon scanning was the entire island of Cyprus. We used a two-step consensus-building process in which experts reviewed and scored lists of alien species on their likelihood of arrival, establishment and potential to affect biodiversity, ecosystems and/or human health in the next 10 years. We reviewed 225 alien species, considered to be currently absent on Cyprus, across taxa and environments. We agreed upon 100 species that constituted very high, high or medium biodiversity risk, often arriving through multiple pathways of introduction. The remaining 125 species were ranked as low risk. The potential impacts on human health were documented for all 225 species; 82 species were considered to have a potentially negative impact on human health ranging from nuisance to disease transmission. The scope of the horizon scanning was the entire island of Cyprus, but the thematic groups also considered the relevance of the top 100 species to the Sovereign Base Areas of Cyprus, given their differing governance. This horizon scan provides the first systematic exercise to identify invasive alien species of potential concern to biodiversity and ecosystems but also human health within the Mediterranean region. The process and outcomes should provide other islands in the region and beyond with baseline data to improve IAS prioritisation and management

Protecting a heterogeneous landscape supports avian diversity across seasons on a Mediterranean island

Conservation efforts commonly target the protection of specific threatened species and habitats, with the value of heterogeneous landscapes often overlooked. Areas with small fragments of habitat tend to receive little attention, but the overall habitat mosaic may support substantial biodiversity. In this work, we investigated seasonal bird–habitat associations on Akrotiri Peninsula, Cyprus, a well-known migration bottleneck site. The area comprises a heterogeneous landscape of diverse but fragmented habitats, with extensive wetlands rich in bird species. We mapped habitat types across the study area, and performed 388 point counts to record bird species richness and abundance in each season for 1 year. A total of 6255 individuals of 115 species were recorded. The study revealed that species were clustered within and around freshwater bodies, and taller and structurally more complex habitats. Seasonal patterns showed that winter and spring seasons supported greater richness of species and numbers of individuals compared to summer and autumn. Overall, we show that water availability and structural complexity of habitat types are positively correlated with both species richness and abundance. Our comprehensive seasonal bird–habitat association study in a protected, designated site, highlights the value of protecting a heterogeneous landscape in its entirety because of the overall diversity it can support across seasons

Breeding success of Eleonora's Falcon in Cyprus revisited using survey techniques for cliff-nesting species

The global breeding population of Eleonora's Falcon (Falco eleonorae) is distributed from the Canary Islands in the west, across the Mediterranean Sea, to Cyprus in the east. The remoteness of nesting colonies, which are predominantly located on sea cliffs and islets, renders breeding success estimation a challenging task, requiring a composite approach to assess each of the breeding stages. Early estimates of the breeding success of Eleonora's Falcon suggested that the Akrotiri colony in Cyprus had the lowest breeding success among all the colonies throughout the species' breeding range, at a level seemingly unsustainable, suggesting the colony might have been in danger of gradual extinction. Here we use a diversity of survey methods including boat, ground, and aerial surveys, with the incorporation of photography and photogrammetry, to reassess the breeding success and the effect of nest characteristics on the Eleonora's Falcon breeding population in Cyprus. During a 6-yr study, we found that Cyprus hosts ∼138 ± 8 breeding pairs and that breeding success equals 1.54 ± 0.85 fledglings per breeding pair, and thus is considerably higher than previous estimates. In addition, by analyzing temporal variation in breeding and nest characteristics, we found that early breeding and reuse of nests positively influence breeding success, but physical nest characteristics have a limited effect on colony productivity. The range of survey methods employed, as well as the array of photography techniques utilized, enhanced the efficiency and accuracy of this study, allowing us to overcome the challenge of inaccessibility of nesting cliffs. LAY SUMMARY In this study we reassessed the breeding success and population status of Eleonora's Falcon in Cyprus, a species nesting on inaccessible sea cliffs. Low breeding success estimates from previous surveys suggested that the breeding population was unsustainable. We used ground, aerial (drone), and boat surveys, combined with photogrammetry for nesting cliff 3-D modeling, to assess breeding success and nest site suitability. Our results show that breeding success of Eleonora's Falcon is higher than previous estimates and that the population is stable. The methods employed enhanced the efficiency and accuracy of our surveys, allowing us to overcome the challenge of inaccessibility of nesting cliffs

Current and future suitability of wintering grounds for a long-distance migratory raptor

Conservation of migratory species faces the challenge of understanding the ecological requirements of individuals living in two geographically separated regions. In some cases, the entire population of widely distributed species congregates at relatively small wintering areas and hence, these areas become a priority for the species’ conservation. Satellite telemetry allows fine tracking of animal movements and distribution in those less known, often remote areas. Through integrating satellite and GPS data from five separated populations comprising most of the breeding range, we created a wide habitat suitability model for the Eleonora’s falcon on its wintering grounds in Madagascar. On this basis, we further investigated, for the first time, the impact of climate change on the future suitability of the species’ wintering areas. Eleonora’s falcons are mainly distributed in the north and along the east of Madagascar, exhibiting strong site fidelity over years. The current species’ distribution pattern is associated with climatic factors, which are likely related to food availability. The extent of suitable areas for Eleonora’s falcon is expected to increase in the future. The integration of habitat use information and climatic projections may provide insights on the consequences of global environmental changes for the long-term persistence of migratory species populations.Peer reviewe