Wind Tunnel Studies of Temperature Dependence and Behavior of Butterflies in the Context of Habitat Dgese
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Ecology, Evolution and Organismal Biology Publications Ecology, Evolution and Organismal Biology 6-2015 Wind Tunnel Studies of Temperature Dependence and Behavior of Butterflies in the Context of Habitat dgesE J. Rhea S. Waldman Iowa State University Diane M. Debinski Iowa State University, [email protected] Follow this and additional works at: https://lib.dr.iastate.edu/eeob_ag_pubs Part of the Behavior and Ethology Commons, and the Entomology Commons The complete bibliographic information for this item can be found at https://lib.dr.iastate.edu/ eeob_ag_pubs/423. For information on how to cite this item, please visit http://lib.dr.iastate.edu/howtocite.html. This Article is brought to you for free and open access by the Ecology, Evolution and Organismal Biology at Iowa State University Digital Repository. It has been accepted for inclusion in Ecology, Evolution and Organismal Biology Publications by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Wind Tunnel Studies of Temperature Dependence and Behavior of Butterflies in the Context of Habitat Edges Abstract Wind tunnel studies provide a valuable experimental approach that can be used to investigate the influence of specific environmental parameters and to make generalizations about insect behavior. In this study, we designed an experiment to test the sensitivity of butterflies ot isolated environmental parameters in the context of understanding edge responses. We tested the behavior of 21 different butterfly species in esponser to certain stimuli, including food source, feeder color, temperature, and UV light. Certain butterfly species (e.g. Heliconius melpomene and Papilio polytes) were particularly active in the wind tunnel setup. All butterfly species tested preferred blue feeders over white, yellow or pink. Investigation of the UV content of the different feeders and the butterflies' preferred nectar plant showed a similar wavelength response, which could indicate a UV preference in butterflies. eW also observed species-dependent temperature preferences. Papilio lowii had a significant preference for the warm side (36.0°C) of the wind tunnel, whereas Papilio polytes showed a significant preference for the cold side (25.3°C). Keywords flight, training, UV, perception, experiments Disciplines Behavior and Ethology | Ecology and Evolutionary Biology | Entomology Comments This article is published as Waldman, Rhea and D.M. Debinski. 2015. Wind Tunnel Studies of Temperature Dependence and Behavior of Butterflies in the Context of Habitat dges.E Journal of the Lepidopterists' Society. 69(2): 125-130. doi: 10.18473/lepi.69i2.a13. Posted with permission. This article is available at Iowa State University Digital Repository: https://lib.dr.iastate.edu/eeob_ag_pubs/423 VOLUME 69, N UMBER 2 125 Journal of the Lepidopterists’ Society 69(2), 2015, 125 –130 WIND TUNNEL STUDIES OF TEMPERATURE DEPENDENCE AND BEHAVIOR OF BUTTERFLIES IN THE CONTEXT OF HABITAT EDGES J. R HEA S. W ALDMAN * AND DIANE M. D EBINSKI Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, IA 50011, USA * previously published as R. von Busse, email: [email protected] ABSTRACT. Wind tunnel studies provide a valuable experimental approach that can be used to investigate the influence of specific environ - mental parameters and to make generalizations about insect behavior. In this study, we designed an experiment to test the sensitivity of butter - flies to isolated environmental parameters in the context of understanding edge responses. We tested the behavior of 21 different butterfly species in response to certain stimuli, including food source, feeder color, temperature, and UV light. Certain butterfly species (e.g. Heliconius melpomene and Papilio polytes ) were particularly active in the wind tunnel setup. All butterfly species tested preferred blue feeders over white, yellow or pink. Investigation of the UV content of the different feeders and the butterflies’ preferred nectar plant showed a similar wavelength response, which could indicate a UV preference in butterflies. We also observed species-dependent temperature preferences. Papilio lowii had a significant pref - erence for the warm side (36.0°C) of the wind tunnel, whereas Papilio polytes showed a significant preference for the cold side (25.3°C). Additional key words: flight, training, UV, perception, experiments Wind tunnel studies have long been used to responses to edges could influence the dispersal and investigate animal flight (e.g. Pennycuick 1968, Tucker recolonization of restored habitats by butterfly species, 1968). The biggest advantage of wind tunnel use is the thereby affecting the function of the restored ecosystem. ability to simplify a complex natural environment and The conceptual model driving our wind tunnel allow for controllable and repeatable measurements. To experiment combines free flight in the context of a ensure non-biased results of a lab or wind tunnel study, simplified environment to allow assessment of choice. By the experimental design needs to be adjusted carefully to allowing the butterflies to fly freely in a confined space, represent conditions pertinent to the research question. an opportunity is provided for the researcher to evaluate Previous training and behavioral testing of the study selection for or against a particular environmental species or individual can be essential for the success of variable. The wind tunnel test section is divided into two the experiment (e.g. Pennycuick 1968). However, parts, with one environmental parameter (e.g., training butterflies presents a different set of challenges temperature) varying across the two parts of the wind than training vertebrates, like birds or bats, and the tunnel. An identical food source in each compartment is butterflies’ perception and learning capabilities need to provided and the butterflies’ preference is observed, be taken into account. Current studies by van Dyck (e.g., recorded, and analyzed. Certain prerequisites, however, 2011) acknowledge a species’ perception of its need to be achieved to promote the success of the environment and highlight the importance of experiments. The butterflies need to be acclimatized to incorporating this species-specific perception when the wind tunnel conditions and be willing to fly around applying research questions to natural environments. the wind tunnel and feed from the offered food source. Our study was designed to investigate the sensitivity of This involves prior training of the butterflies and butterflies to environmental parameters in the context of appropriate environmental conditions to keep the edge responses. Current habitat restorations aim to butterflies active. To ensure the validity of the restore the function of original ecosystems and one experiment, it is further necessary that the two measure of restoration success is the composition of the compartments of the wind tunnel are identical except for insect community. Butterflies are particularly good the parameter to be tested. For example, if the test indicators because they are easily identifiable and are involves an artificial food source, the two sides of the associated with the plant community both as herbivores chamber should not vary in smell, food quality, amount, and pollinators (e.g., Kremen 1992, Brown & Freitas etc. Here we present preliminary results with a focus on 2000, Shepherd & Debinski 2005). However, some developing an experimental protocol that will provide a grassland butterfly species react strongly to the presence basis for future butterfly behavioral research using wind of habitat edges and show differential probabilities for tunnels. crossing edges between different land cover types (e.g., road, treeline, field, or crop) (Ries & Debinski 2001). MATERIALS AND METHODS The landscape today in most parts of the developed Butterfly species. Table 1 provides an overview of world is highly fragmented and these behavioral the 21 butterfly species tested in the wind tunnel. The Downloaded From: https://bioone.org/journals/The-Journal-of-the-Lepidopterists'-Society on 17 Aug 2020 Terms of Use: https://bioone.org/terms-of-use Access provided by Iowa State University 126 126 JOURNAL OF THE LEPIDOPTERISTS ’ S OCIETY butterflies were supplied from the butterfly house of the well as fast and slow flying species. This allowed us to Reiman Gardens at Iowa State University, where they assess a wide variety of potential behavioral differences were reared from caterpillars. All caterpillars were within the wind tunnel. The butterfly behavior is obtained from commercial butterfly farms and were summarized in Table 1 and an assessment of the most likely reared in captivity for several generations. suitability of the species for these kinds of wind tunnel Butterflies taken straight out of the rearing chamber experiments is described. Two species, Heliconius where they had recently emerged were generally melpomene and Papilio polytes , were by far the most inactive for about 24 h. Active butterflies caught in the active and displayed the desired feeding behavior. All butterfly house needed a couple of hours to adjust to other tested longwings showed similar activity levels and wind tunnel conditions. The most success (i.e., the most behavior, indicating a general suitability of this genus for activity) was attained by keeping individuals in the wind wind tunnel experiments. Even by keeping individuals in tunnel for several consecutive days. The tested species the