TY - JOUR

T1 - A new method for collecting agile tiger beetles by live pitfall trapping

AU - Taboada Palomares, Angela

AU - Pérez-Aguirre, Carlos

AU - Aßmann, Thorsten

PY - 2012/10

Y1 - 2012/10

N2 - Most tiger beetles of the genus Cicindela (Coleoptera: Carabidae: Cicindelinae) are restricted to a singular habitat type, which supports the entire life cycle of the given species (Simon-Reising et al., 1996; Pearson & Vogler, 2001). Many of them primarily thrive on sun-exposed sandy ground with sparse vegetation (Lindroth, 1985), where adults attain high body temperature for top speed locomotion, mate encounters, and prey pursuits (Pearson, 1988; Pearson & Vogler, 2001). During daily movements, adult tiger beetles usually run in short but prompt sprints, alternated by brief pauses (Pearson, 1988; Gilbert, 1997), often along paths, or they fly low over bare areas. Because they are rapid runners and agile fliers with excellent vision and sensitive tympanum (Pearson, 1988; Pearson & Vogler, 2001), adults are generally challenging to capture. Adults react promptly to abrupt movements of approaching collectors from great distances (Pearson & Vogler, 2001). When disturbed, they suddenly run or fly away, usually short distances, but sometimes to adjacent patches of tall vegetation, where they may be difficult to trace (Boyce & Walters, 2010). Besides escape running and flight, additional mechanisms of predatory avoidance may complicate capture, such as cryptic coloration and camouflage against the substrate texture (Pearson, 1988; Pearson & Vogler, 2001). Likewise, warning behaviour, including stridulation and the release of defence compounds, may alert conspecifics against the collector, thus altering beetle behaviour and biasing collection records (Pearson, 1988).Direct observations as well as various collection techniques have successfully been used to survey tiger beetles (Pearson & Vogler, 2001; Cassola et al., 2006; Irmler, 2010). For the live capturing of adults, hand netting during daytime has been suggested to be the most effective method (Pearson & Vogler, 2001; Nageleisen & Bouget, 2009). Yet, successful capture demands prior practice to develop essential skills in approaching the beetle and handling the net (Pearson & Vogler, 2001). Likewise, recording adult tiger beetles by walking transects requires previous training in individual detectability, as well as repeated visits (Hudgins et al., 2012). For both techniques, accurate occurrence data depend on the observer's ability to identify the position where the individual was first seen and to distinguish it from subsequent positions after escape flight. Continuous or simultaneous surveys over large areas or among locations would require a significant increase in sampling effort (i.e., in number of visits or observers/collectors) (see Dodd, 2011; Hudgins et al., 2011, 2012).Despite the numerous factors affecting pitfall trapping (e.g., trap position, size, and material; Luff, 1975; Adis, 1979), this method has the potential of producing maximum adult catches and recording the beetle's exact position over wide sampling areas, without the presence of the observer, at the same time allowing for standardization. Although non-fatal pitfall trapping has produced adequate captures for flightless tiger beetles (e.g., Brust et al., 2005), none of the attempts to live trap flying species has succeeded so far (Samu & Sárospataki, 1995; Nageleisen & Bouget, 2009; Dodd, 2011). In this study, we tested the effectiveness of several types of dry pitfall traps in capturing and retaining flying tiger beetles alive. Further modifications of the trap designs were introduced to improve catchability and to reduce escape rates of the trapped specimens. Our objective was to determine the most suitable trapping technique for collecting sufficient sample sizes of a targeted species, while removing collector bias.

AB - Most tiger beetles of the genus Cicindela (Coleoptera: Carabidae: Cicindelinae) are restricted to a singular habitat type, which supports the entire life cycle of the given species (Simon-Reising et al., 1996; Pearson & Vogler, 2001). Many of them primarily thrive on sun-exposed sandy ground with sparse vegetation (Lindroth, 1985), where adults attain high body temperature for top speed locomotion, mate encounters, and prey pursuits (Pearson, 1988; Pearson & Vogler, 2001). During daily movements, adult tiger beetles usually run in short but prompt sprints, alternated by brief pauses (Pearson, 1988; Gilbert, 1997), often along paths, or they fly low over bare areas. Because they are rapid runners and agile fliers with excellent vision and sensitive tympanum (Pearson, 1988; Pearson & Vogler, 2001), adults are generally challenging to capture. Adults react promptly to abrupt movements of approaching collectors from great distances (Pearson & Vogler, 2001). When disturbed, they suddenly run or fly away, usually short distances, but sometimes to adjacent patches of tall vegetation, where they may be difficult to trace (Boyce & Walters, 2010). Besides escape running and flight, additional mechanisms of predatory avoidance may complicate capture, such as cryptic coloration and camouflage against the substrate texture (Pearson, 1988; Pearson & Vogler, 2001). Likewise, warning behaviour, including stridulation and the release of defence compounds, may alert conspecifics against the collector, thus altering beetle behaviour and biasing collection records (Pearson, 1988).Direct observations as well as various collection techniques have successfully been used to survey tiger beetles (Pearson & Vogler, 2001; Cassola et al., 2006; Irmler, 2010). For the live capturing of adults, hand netting during daytime has been suggested to be the most effective method (Pearson & Vogler, 2001; Nageleisen & Bouget, 2009). Yet, successful capture demands prior practice to develop essential skills in approaching the beetle and handling the net (Pearson & Vogler, 2001). Likewise, recording adult tiger beetles by walking transects requires previous training in individual detectability, as well as repeated visits (Hudgins et al., 2012). For both techniques, accurate occurrence data depend on the observer's ability to identify the position where the individual was first seen and to distinguish it from subsequent positions after escape flight. Continuous or simultaneous surveys over large areas or among locations would require a significant increase in sampling effort (i.e., in number of visits or observers/collectors) (see Dodd, 2011; Hudgins et al., 2011, 2012).Despite the numerous factors affecting pitfall trapping (e.g., trap position, size, and material; Luff, 1975; Adis, 1979), this method has the potential of producing maximum adult catches and recording the beetle's exact position over wide sampling areas, without the presence of the observer, at the same time allowing for standardization. Although non-fatal pitfall trapping has produced adequate captures for flightless tiger beetles (e.g., Brust et al., 2005), none of the attempts to live trap flying species has succeeded so far (Samu & Sárospataki, 1995; Nageleisen & Bouget, 2009; Dodd, 2011). In this study, we tested the effectiveness of several types of dry pitfall traps in capturing and retaining flying tiger beetles alive. Further modifications of the trap designs were introduced to improve catchability and to reduce escape rates of the trapped specimens. Our objective was to determine the most suitable trapping technique for collecting sufficient sample sizes of a targeted species, while removing collector bias.

KW - Biology

KW - Calluna vulgaris heathland

KW - Carabidae

KW - Cicindela campestris

KW - Cicindela sylvatica

KW - Cicindelinae

KW - Coleoptera

KW - Sampling technique

KW - Ecosystems Research

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-84865784350&origin=inward&txGid=0

U2 - 10.1111/j.1570-7458.2012.01316.x

DO - 10.1111/j.1570-7458.2012.01316.x

M3 - Journal articles

VL - 145

SP - 82

EP - 87

JO - Entomologia Experimentalis et Applicata

JF - Entomologia Experimentalis et Applicata

SN - 0013-8703

IS - 1

ER -