Abstract
Rainfall is a common phenomenon in tropical forests influencing the behavior of many animals, however, little is known about its post-occurrence effect on behavior. We investigated the effect of diurnal rainfall on the nocturnal activity of the wandering spider species Phoneutria reidyi in nights without rainfall. Our study included two different areas and periods: a coconut plantation, located 108 km from the city of Manaus, containing an area of 80 m x 80 m with 105 palms, from July 2014 to July 2015; and an area of 80 m x 80 m in a rainforest fragment in Manaus, from December 2015 to March 2016. Each night, we counted active spiders (found outside refugees) searching carefully on the vegetation and on the ground using a headlamp between 19:00-00:00. Spiders were not captured to avoid the effect of disturbance, and were measured by approaching a caliper rule. We used an index to measure the diurnal rainfall effect (DRE) which was the percentage of change in the number of active spiders at night after a diurnal rainfall, considering 100 % the number of spiders active at the previous or following night, without previous rainfall during the day. This pairwise approach was used to avoid seasonal bias and included 15 pairs of nights in the plantation, and 15 pairs in the forest. A total of 2 243 active spiders were counted. The number of active spiders was always smaller in nights after diurnal rainfall, with a mean reduction of 53.4 %. The abundance of active spiders reduced significantly in both areas after a diurnal rainfall, and the effect was not different between areas. Larger spiders (mostly adults) reduced their activity (-62.8 %) more than smaller spiders (juveniles, -48.5 %). The amount of rainfall during the day had no effect on the nocturnal activity, i.e., the effect of strong diurnal rainfall is similar to the effect of a weak rainfall. The air temperature did not change significantly at night after diurnal rainfalls. The seasonality of rainfall apparently has a weak or absent effect on the abundance of P. reidyi, which was approximately constant through one year. We believe that the moisture, which may affect the chemical cues of prey, is the major cause to reduce the active spiders after rainfall, but we discuss other potential causes. Smaller individuals are probably more active under less favorable conditions due to the stronger need of food for growing. If this effect of rainfall on the behavior is common for wandering spiders in general, the rainfall events may have important consequences for the entire community of arthropods and small vertebrates. We suggest that studies based on relative abundance of spiders should take in account this potential effect in collection and analysis of data.
References
Barth, F. G. (2002). Spider senses - technical perfection and biology. Zoology, 105, 271-285.
Barth, F. G., Seyfarth, E. A., Bleckmann, H., & Schüch, W. (1988). Spiders of the genus Cupiennius Simon 1891 (Araneae: Ctenidae). Oecologia, 77, 187-193.
Cardoso, J. L. C., França, F. O. S., Wen, F. H., Malaque, C. M. S., & Haddad-Jr, V. (2009). Animais Peçonhentos no Brasil: Biologia Clínica e Terapêutica dos Acidentes. 2ª Edição. São Paulo, Brasil: Sarvier.
Carvalho, L. S., Sebastion, N., Araújo, H. F. P., Dias, S. C., Venticinque, E., Brescovit, A. D., & Vasconcellos, A. (2015). Climatic variables do not directly predict spider richness and abundance in semiarid Caatinga vegetation, Brazil. Environmental Entomology, 44, 54-63.
Chai, Y. Q., & Wilgers, D. J. (2015). Effects of temperature and light levels on refuge use and activity in the wolf spider Rabidosa punctulata. Transactions of the Kansas Academy of Science, 118 (3-4), 194-200.
Efron, B. (1982). The jackknife, the bootstrap and other resampling plans. Philadelphia, Pennsylvania, USA: Society for Industrial and Applied Mathematics.
Gasnier, T. R., & Höfer, H. (2001). Patterns of abundance of four species of wandering spiders (Ctenidae: Ctenus) in a forest in central Amazonia. Journal of Arachnology, 29, 95-103.
Gasnier, T. R., Höfer, H., & Brescovit, A. D. (1995). Factors affecting the “activity density” of spiders on tree trunks in an Amazonian rainforest. Ecotropica, 12, 69-77.
Gibbons, J. W., & Bennet, D. H. (1974). Determination of Anuran Terrestrial Activity Patens by a Drift Fence Method. Copeia, 236-243.
Hazzi, N. A. (2014). Natural history of Phoneutria boliviensis (Araneae: Ctenidae): habitats, reproductive behavior, postembryonic devolopment and prey-wrapping. Journal of Arachnology, 42, 303-310.
Hilton, G. M., Ruxton, G. D., & Cresswell, W. (1999). Choice of foraging area with respect to predation risk in redshanks: The Effects of Weather and Predator Activity. Oikos, 87, 295-302.
Hölldobler, B., & Wilson, E. O. (1990). The ants. Massachusetts, USA: Cambridge.
Hothorn, T., Hornik, K., Mark, A., Wiel, V., & Zeileis, A. (2008). Implementing a Class of Permutation Tests: The coin Package. Journal of Statistical Software, 288, 1-23.
Jocqué, R., Samu, F., & Bird, T. (2005). Density of spiders (Araneae: Ctenidae) in Ivory Coast rainforests. Journal of Zoology, 266, 105-110.
Leisch, F. (2015). Bootstrap: Functions for the Book "An Introduction to the Bootstrap". R package version 2. Retrieved from https://CRAN.R-project.org/package=bootstrap
Lensing, J. R., Todd, S., & Wise, D. H. (2005). The impact of altered precipitation on spatial stratification and activity-densities of springtails (Collembola) and spiders (Araneae). Ecological Entomology, 30, 194-200.
Manly, B. F. J. (2007). Randomization, Bootstrap and Monte Carlos Methods in Biology. Boca Raton, FL, USA: Chapman & Hall.
Marcon, J. L., Crus, J., Menin, M., Carolino, O. T., & Gordo, M. (2012). Biodiversidade fragmentada na floresta do campus da Universidade Federal do Amazonas: Conhecimento Atual e Desafios para a Conservação. In J. L. Marcon, M. Menin, M. G. P. Araújo, & T. Hrbek. Biodiversidade Amazônica: Caracterização, Ecologia e Conservação. Manaus, Brasil: Editora da Universidade Federal do Amazonas.
Martins, R., & Bertani, R. (2007). The non-Amazonian species of the Brazilian wandering spiders of the genus Phoneutria Perty, 1833 (Araneae: Ctenidae), with the description of a new species. Zootaxa, 1526, 1-36.
Medeiros, L. G. S., Bandeira, A. G., & Martius, C. (1999). Termite swarming in the Northeastern Atlantic rain forest of Brazil. Studies on Neotropical Fauna and Environment, 34, 76-87.
Perty, M. (1833). Brasilianische Spinnen. In J. B. de Spix & F. F. Martius (Eds.), Delectus Animalium Articulatorum quae in itinere per brazilian ann. 1817 et 1820 colligerunt (pp. 191-209). Monachii.
Pickard-Cambridge, F. O. (1897). On cteniform spiders from the lower Amazons and other regions of North and South America. The Annals and Magazine of Natural History, 19, 52-106.
Portela, E., Willemar, R. H., & Gasnier, T. R. (2013). Soil type preference and the coexistence of two species of wandering spiders (Ctenus amphora and C. Crulsi: Ctenidae) in a rainforest in Central Amazonia. Journal of Arachnology, 41, 85-87.
Powell, B. E., Brightwell, R. J., & Silverman, J. (2009). Effect of an invasive and native ant on field population of the black citrus aphid (Hemiptera: Aphididae). Environmental Entomology, 38, 1618-1625.
Quinn, G. P., & Keough, M. J. (2003). Experimental design and data analysis for biologists. New York: Cambridge University Press.
R core development team. (2016). R: version 3.3.2. The R project for statistical computing, Vienna, Austria. Retrieved from https://www.r-project.org
Rego, F. N. A. A., Venticinque, E. M., & Brescovit, A. D. (2005). Densidade de aranhas errantes (Ctenidae e Sparassidae, Araneae) em uma floresta fragmentada. Biota Neotropica, 5(1a), 45-52.
Romero, G. Q., & Vasconcellos-Neto, J. (2003). Natural history of Misumenops argenteus (Thomisidae): seasonality and diet on Trichogoniopsis adenantha (Asteraceae). Journal of Arachnology, 31, 297-304.
Simó, M., & Brescovit, A. D. (2001). Revision and cladistic analysis of the neotropical spider genus Phoneutria Perty, 1833 (Araneae: Ctenidae), with notes on related Ctenidae. Bulletin of British Arachnological Society, 122, 67-82.
Spiller, D. A., & Schoener, T. W. (1995). Long-term variation in the effect of lizards on spider density is linked to rainfall. Oecologia, 103, 133-139.
Stamps, J. A. (1976). Rainfall, activity and social behavior in the lizard Anolis aeneus. Animal Behavior, 24, 603-608.
Teixeira, L. T., & Coutinho, E. S. (2002). Hábito alimentar de Proceratophrys boiei (Wied) (Amphibia, Anura, Leptodactylidae) em Santa Teresa, Espírito Santo, sudeste do Brasil. Boletim do Museu Biologia Mello Leitão, 14, 13-20.
Thomas, L., Buckland, S. T., Rexstad, E. A., Laake, J. L., Strindberg, S., Hedley, S. L., Bishop, J. R. B., Marques, T. A., & Burnham, K. P. (2010). Distance software: design and analysis of distance sampling surveys for estimating population size. Journal of Applied Ecology, 47, 5-14.
Torres-Sanchez, M. P., & Gasnier, T. R. (2010). Patterns of abundance, habitat use and body size structure of Phoneutria reidyi and P. fera (Araneae: Ctenidae) in a Central Amazonian rainforest. Journal of Arachnology, 38, 433-440.
Wallace, R. B. (2001). Diurnal activity budgets of black spider monkeys Ateles chamek, in a Southern Amazonian Tropical forest. Neotropical Primates, 9, 101-107.
Wilder, S. M., Devito, J., Persons, M. H., & Rypstra, A. L. (2005). The effects of moisture and heat on the efficacy of chemical cues used in predator detection by Pardosa milvina (Araneae: Lycosidae). Journal Arachnology, 33, 857-861.
Williams, S. C. (1987). Scorpion bionomics. Annual Review of Entomology, 32, 275-95.
Wise, D. H. (1993). Spiders in Ecological Webs. New York: Cambridge University Press.
Zaller, J. G., Simmer, L., Santer, N., Tataw, J. T., Formayer, H., Murer, E., Hösch, J., & Baumgarten, A. (2014). Future rainfall variations reduce abundances of aboveground arthropods in model agroecosystems with different soil types. Frontiers in Environmental Science, 2, 44.
Comments
This work is licensed under a Creative Commons Attribution 4.0 International License.
Copyright (c) 2017 Revista de Biología Tropical