Echolocation call description of 15 species of Middle-Eastern desert dwelling insectivorous bats

Modern advances in acoustic technology have made possible new and broad ranges of research in bioacoustics, particularly with regard to echolocating bats. In the present study, we present an acoustic guide to the calls of 15 species of bats in the Arava rift valley, Israel, with a focus on their bioacoustics, habitat use and explaining differences between similar species. We also describe a potential case of frequency separation where four bat species using six call types appear to separate the frequencies of their calls to minimize overlap. The studied community of bat species is also found in other Middle Eastern deserts including the deserts of Jordan, Syria and Saudi Arabia and we hope that data gathered will benefit other bat researchers in the region

Reshaping our understanding of species’ roles in landscape-scale networks

Data associate with Ecology Letters manuscript number: ELE-01021-2018.R2; Hackett et al. Reshaping our understanding of species’ roles in landscape-scale networks<div><br></div><div>See READ ME text file for specific detail</div

Research priorities for maintaining biodiversity’s contributions to people in Latin America

Maintaining biodiversity is crucial for ensuring human well-being. The authors participated in a workshop held in Palenque, Mexico, in August 2018, that brought together 30 mostly early-career scientists working in different disciplines (natural, social and economic sciences) with the aim of identifying research priorities for studying the contributions of biodiversity to people and how these contributions might be impacted by environmental change. Five main groups of questions emerged: (1) Enhancing the quantity, quality, and availability of biodiversity data; (2) Integrating different knowledge systems; (3) Improved methods for integrating diverse data; (4) Fundamental questions in ecology and evolution; and (5) Multi-level governance across boundaries. We discuss the need for increased capacity building and investment in research programmes to address these challenges

The Importance of Acacia Trees for Insectivorous Bats and Arthropods in the Arava Desert

Anthropogenic habitat modification often has a profound negative impact on the flora and fauna of an ecosystem. In parts of the Middle East, ephemeral rivers (wadis) are characterised by stands of acacia trees. Green, flourishing assemblages of these trees are in decline in several countries, most likely due to human-induced water stress and habitat changes. We examined the importance of healthy acacia stands for bats and their arthropod prey in comparison to other natural and artificial habitats available in the Arava desert of Israel. We assessed bat activity and species richness through acoustic monitoring for entire nights and concurrently collected arthropods using light and pit traps. Dense green stands of acacia trees were the most important natural desert habitat for insectivorous bats. Irrigated gardens and parks in villages and fields of date palms had high arthropod levels but only village sites rivalled acacia trees in bat activity level. We confirmed up to 13 bat species around a single patch of acacia trees; one of the richest sites in any natural desert habitat in Israel. Some bat species utilised artificial sites; others were found almost exclusively in natural habitats. Two rare species (Barbastella leucomelas and Nycteris thebaica) were identified solely around acacia trees. We provide strong evidence that acacia trees are of unique importance to the community of insectivorous desert-dwelling bats, and that the health of the trees is crucial to their value as a foraging resource. Consequently, conservation efforts for acacia habitats, and in particular for the green more densely packed stands of trees, need to increase to protect this vital habitat for an entire community of protected bats

A whispering bat that screams:Bimodal switch of foraging guild from gleaning to aerial hawking in the desert long-eared bat

Abstract Echolocating bats have historically been classified as either loud aerial-hawkers or whispering gleaners. Some bat species can forage in multiple ways and others have demonstrated limited flexibility in the amplitude of their echolocation calls. The desert long-eared bat, Otonycteris hemprichii, has been said to be a passive gleaning whispering bat preying on terrestrial arthropods such as scorpions. Using an acoustic tracking system we recorded individuals flying at foraging and drinking sites and compared their flight height, flight speed, call duration, pulse interval and source levels to gleaning individuals previously recorded using the same setup. We found differences in all variables with the strongest difference in source levels where bats called at a mean of 119 dBpeSPL (compared to 75 dBpeSPL when gleaning). Bat faecal analysis indicated that their diet differed from previous studies and that prey species were capable of flight. We conclude that the bats switched from passive gleaning to capturing airborne insects (aerial-hawking). While whispering bats have been known to opportunistically catch insects on the wing, in the present study we show a full bimodal switch between foraging guilds with the respective changes in source level to those typical of a true aerial-hawker.</jats:p

The percentage of recorded bat passes in each habitat per species.

<p>R.ha: <i>Rhinopoma hardwickii</i>, R.mi: <i>R. microphyllum</i>, A.tr: <i>Asellia tridens</i>, R.hi: <i>Rhinolophus hipposideros</i>, R.cl: <i>R. clivosus</i>, P.ku: <i>Pipistrellus kuhlii</i>, H.bo: <i>Hypsugo bodenheimeri</i>, E.bo: <i>Eptesicus bottae</i>, O.he: <i>Otonycteris hemprichii</i>, P.ch: <i>Plecotus christii</i>, T.te: <i>Tadarida teniotis</i>. Numbers in brackets indicate the total number of passes for that species.</p

Regional and global conservation status of recorded bat species.

<p>Regional and global conservation status of recorded bat species.</p

The relationship between arthropod abundance and bat activity.

<p>Each data point represents one entire night of sampling. Solid line is a linear regression (y = 0.627×−0.028; R² = 0.21; t₈₈ = 4.81, p<0.001).</p

Satellite map of sites.

<p>A is dense acacia stands, S is sparse acacia stands, B is barren acacia stands, N is non-acacia desert sites, V is village sites and D is date plantations. The five replicates of each habitat type are numbered one to five from north to south (Reprinted with permission from Esri, original copyright 2012).</p