Sociobiology 61(2): 225-233 (June, 2014) DOI: 10.13102/sociobiology.v61i2.225-233 Sociobiology An international journal on social insects Research article - WASPS The Social Wasp Fauna of a Riparian Forest in Southeastern Brazil (Hymenoptera, Vespidae) GA Locher1, OC Togni1, OT Silveira2, E Giannotti1 Abstract 1 - Instituto de Biociências, Universidade Estadual Paulista, Rio Claro, SP, Brazil. 2 - Museu Paraense Emílio Goeldi, Belém, PA, Brazil. Article History An inventory of social wasps was carried out on a monthly basis, from March 2010 to Edited by March 2011 in a section of riparian forest along the Passa-Cinco River in Ipeúna, São Gilberto M M Santos, UEFS, Brazil Paulo state, Brazil. Two active collecting methods (active collecting and point sampling Received 23 August 2013 Initial acceptance 21 November 2013 using a liquid bait) and one passive method (baited PET bottle trap) were used. The re- Final acceptance 23 March 2014 sults increased the data on the diversity of social wasps of the State and were used to compare richness, equitability and diversity obtained with several collecting methods Keywords which have been employed to social wasps. Thirty-one species belonging to eight ge- Richness, abundance, Polistinae, nera were recorded; the most abundant were Agelaia vicina (de Saussure) and Agelaia attractive traps, active sampling pallipes (Olivier). Both species belong to the tribe Epiponini, which was dominant in the Corresponding author sample. Regarding sampling methods, the active collecting ones sampled the greatest Gabriela de Almeida Locher richness value and the highest Shannon-Wiener diversity index and also presented the Departamento de Zoologia largest number of exclusive species. However, the other methods have also obtained Instituto de Biociências exclusive species. Universidade Estadual Paulista 13506-900 Rio Claro, SP, Brazil E-Mail: [email protected] Introduction group of insects, researches related to diversity of social wasps in this country are increasing in number and have covered Native forests have been exploited for years in a different regions, environments and biomes (Richards, 1978; degrading manner, resulting in a number of environmental Rodrigues & Machado, 1982; Marques, 1989; Marques et al., problems such as species extinctions, local climate change, 1993; Diniz & Kitayama, 1994; Mechi, 1996; Santos, 1996; soil erosion, siltation and eutrophication of watercourses Lima et al., 2000; Raw, 2003; Marques et al., 2005; Mechi, (Ferreira & Dias, 2004). In order to monitor the effects of 2005; Melo et al., 2005; Hermes & Köhler, 2006; Santos et al., changes in the environment, to develop conservation strate- 2006; Silva-Pereira & Santos, 2006; Souza & Prezoto, 2006; gies on a local scale, information on biodiversity of an area is Elpino-Campos et al., 2007; Santos et al., 2007; Morato et al., essential. The concept of diversity can be divided into alpha, 2008; Ribeiro Junior, 2008; Silveira et al., 2008; Souza et al., beta and gamma, namely the biological diversity in natural 2008; Gomes & Noll, 2009; Santos et al., 2009a; Santos et and changed communities, the biodiversity exchange rate be- al., 2009b; Alvarenga et al., 2010; Auad et al., 2010; Lima et tween different communities, and the species richness of all al., 2010; Prezoto & Clemente, 2010; Santos & Presley, 2010; the communities which integrate a landscape, respectively Souza et al., 2010; Pereira & Antonialli-Junior, 2011; Silva (Moreno, 2001). An inventory of a local fauna which generates et al. 2011; Souza et al., 2011; Tanaka Junior & Noll, 2011; data on alpha diversity is the first step in conservation biology. Jacques et al., 2012; Silveira et al., 2012; Simões et al., 2012 Brazil hosts a great diversity of social wasps, reaching ; Auko & Silvestre, 2013; Grandinete & Noll, 2013; Togni et a total of 319 species, about 33% of the social wasp species al. 2014). In the State of São Paulo, studies on diversity of described worldwide (Prezoto et al., 2007). Due to this high social wasps are still scarce, mainly focusing on the North- diversity and the importance that has been assigned to this western region, with studies in localities such as Paulo de Open access journal: http://periodicos.uefs.br/ojs/index.php/sociobiology ISSN: 0361-6525 226 GA Locher et al - The Social Wasp Fauna of a Riparian Forest Faria, Pindorama and Neves Paulista (Gomes & Noll, 2009), logical net, at the time of greatest foraging activity between Patrocínio Paulista (Lima et al., 2010), Magda, Bebedouro, 10:00 am to 3:00 pm (see Prezoto et al., 2008). Rounds of Matão and Barretos (Tanaka Junior & Noll, 2011); on the active collecting were made at two different days each month Central Eastern region, with researches in Rio Claro (Rodri- by four independent collectors on the same transect where gues & Machado, 1982), Luíz Antônio, Corumbataí (Mechi, the bottle traps were placed. The collected individuals were 1996), and Santa Rita do Passa Quatro (Mechi, 2005); and associated with the nearest trap point for further analysis and finally at the Littoral in Ubatuba (Togni et al., 2014). comparisons. According to the above information, this study aimed The method of point sampling using a liquid bait was to conduct an inventory of the diversity of social wasps in made with a sucrose solution (1: 4, commercial sugar: water) an area of Riparian Forest in the Central Eastern region of with 2 cm³ of salt for each half liter of solution which was São Paulo State, increasing the data on the diversity of social sprayed over the vegetation at 10 marked points along the wasps of the State and to compare richness, equitability and sampling trail (with a distance of 100 meters between points). diversity obtained through the several methods used. At least 30 minutes after spraying, active searching was per- formed by two independent collectors on the vegetation for 3 Materials and Methods minutes with the aid of an entomological net (modified from Liow et al., 2001; Lima et al., 2010; Tanaka Junior & Noll, Social wasps (Vespidae, Polistinae) were sampled 2011). monthly from March 2010 to March 2011 along the western The species relative abundances were computed by di- edge of a riparian forest fragment (semideciduous alluvial viding the number of collected individuals of each species by forest, according to Rodrigues, 1999) by the margins of the the total abundance found (expressed as percentage) and the Passa-Cinco River, in a landscape with the surrounding ma- richness value is the total number of species encountered. trix composed by sugarcane plantations, in the rural munici- The richness value obtained by each method was di- pality of Ipeúna - State of São Paulo (22 ° 24’52 .55 “S, 47 vided by the total richness sampled to evaluate the efficiency ° 43’35 .55” W). The Passa-Cinco is one of the main rivers of each of them. We calculated the Shannon-Wiener index of the Corumbataí River Basin, in a region that presents a and Equitability of samples obtained by each method accord- subtropical climate (Köppen Cwa type) characterized by dry ing to the formulas from Krebs (1998) in order to compare winter and rainy summer, with an average temperature in the the diversity sampled by each of them. warmest month of up to 22˚C (Palma-Silva, 1999). Originally, The rarefaction curve based on samples was obtained the watershed vegetation was mainly composed of semide- using the Mao Tau estimator (Colwell et al., 2004) calculated ciduous forests, and “cerrado” vegetation spots in smaller with EstimateS- version 8.2 (Colwell, 2009) and used to areas (Koffler, 1993 as cited inValente & Vettorazzi, 2002). compare the three methods based on the monthly richness According to Valente and Vettorazzi (2002) the sub-basin of sampling effort. The species accumulation curve for months of Passa-Cinco River had in year 2000 51.72% of its surface collection was calculated through the addition of new species occupied by pasture areas, 14.3% by sugarcane, 15.67% na- found every month. tive forest, 10.5% planted forest, 0.74% Cerrado, 0.5% urban To analyze the equality of samples obtained from each areas and 6.47% by others. sampling method, the Kruskal-Wallis test (BioEstat 5.0 version Three different methods were used for sampling the 5.0 (Ayres et al., 2007)) was used. For the test, the raw abundance wasps: baited PET bottle trap, active collecting, and point data of each species, and the relative abundances (percentage), sampling using a liquid bait. The baited PET bottle trap were used. method consisted in 10 attractive traps made with 2 L PET type bottles (Polyethylene Terephthalate Bottles) installed Results and Discussion along a 1000 meter trail bordered by riparian vegetation and sugarcane plantation. The traps were set on the edge of the Social wasps community in Ipeúna - SP vegetation at a height of approximately 1.5 meters (Ribeiro Junior, 2008), with a 100 meters interval between traps (Togni After 13 months of sampling activity in the rural area et al., 2014). Each bottle had four circular orifices at the mid- in Ipeúna, São Paulo state, 31 species of eight genera of social dle, and contained 200 ml of attractive liquid (modified from wasps were found. A total of 954 individuals was collect- Souza & Prezoto, 2006) consisting of natural industrialized ed and 86.58% belonged to the Epiponini tribe, while only guava juice and sugar solution (Togni et al., 2014). After a 9.43% belonged to the tribe Polistini and 3.98% to the tribe week, traps were removed, the attractive