Seed removal by ants in Brazilian savanna: optimizing fieldwork

There has been an increase in the number of studies using seed removal by ants to evaluate ecosystem functioning; however, these studies encompassed varying time periods and used different types of seeds. Therefore, our aim was to evaluate differences in the proportion of seeds removed by ants in impacted and non-impacted sites in Brazilian savanna. Furthermore, we evaluated seed removal (1) during the morning and after a 24h period of seed exposure and (2) using natural and artificial seeds (manipulated resource to resemble natural seeds). The proportion of seeds removed was higher after the 24h exposure period (artificial seeds) regardless of site status, and more artificial seeds were removed than natural seeds. Our recommendations regarding sampling period depend on whether evaluating impacted or non-impacted sites. Although seed removal was greater after 24h in both impacted and non-impacted sites, we suggest that research evaluating the proportion of seeds removed in non-impacted sites should be performed only in the morning period to optimize the sampling time (removal of 60% during this period). When the aim is to compare non-impacted and impacted sites, we suggest evaluating after 24h of exposure, since the impacted sites experienced a higher proportion of seed removal during the afternoon and/or night time periods. Furthermore, we recommend the use of artificial seeds because they are easier to obtain and manipulate, and allow us to do comparisons between studies at different regions. We consider these findings an important first step towards standardizing future research on seed removal in Brazilian savannas by facilitating fieldwork and allowing comparisons to be made among different studies

Canopy and Litter Cover Do Not Alter Diaspore Removal by Ants in the Cerrado

Diaspore removal by ants is a crucial stage for successful myrmecochory and can be directly or indirectly affected by natural or anthropic changes to environments. Among the consequences of such changes is variation in habitat attributes, such as changes in conditions and resources and, consequently, decreased diaspore removal or even the loss of this ecological function. The aim of this study was to assess whether canopy and litter cover affect diaspore removal by ants in the Cerrado. We considered canopy and litter cover as proxies of humidity and temperature and evaluated whether changes in these environmental conditions could affect diaspore removal by ants. We hypothesized that the greater the canopy and litter cover (higher humidity and lower temperature), the greater the number of diaspores removed by ants. We tested this hypothesis by establishing three classes of cover for each proxy: low, intermediate, and high. We placed artificial diaspores under each cover class and quantified the number of diaspores removed. We found that variation in canopy and litter cover did not affect the number of diaspores removed by ants in areas of cerrado sensu stricto. Variation in habitat attributes in natural environments were less important for diaspore removal than in modified areas. Our results indicate that understanding the processes and habitat atributes involved in diaspore removal by ants is important for conserving the Cerrado

Invasion and establishment of digitonthophagus gazella (Fabricius) (Coleoptera: scarabaeidae) in transition fragment atlantic forest

Digitonthophagus gazella is known worldwide because it has been introduced in tropical and subtropical regions of several countries. The aim of this introduction was to assist in the removal of dung pats in pasture areas and to aid in the biological control of flies of veterinary importance. Thus, although D. gazella has a preference for open and sunny habitats and herbaceous vegetation, there is evidence that it apparently has been adapting to closed-canopy areas. Therefore, this study aimed at evaluating the ability of D. gazella to develop in a forest environment. The study was conducted in 2012 and 2013 in the Farm of UNESP - Ilha Solteira in Mato Grosso do Sul, Brazil. To evaluate the presence of D. gazella in the forest were used pitfall traps and to verify its capability of develop in this habitat couples of this species were kept in pasture and forest fragment in the absence and presence of competitors. The results indicate that D. gazella is able to enter the forest fragment, but at short distances from the edge. Additionally, D. gazella was not able to develop and establishment in the forest fragment.Financiadora de Estudos e ProjetosA espécie Digitonthophagus gazella é conhecida mundialmente pelo fato de ter sido introduzida em regiões tropicais e subtropicais de vários países. O objetivo dessas introduções foi o de auxiliar na remoção de massas fecais em áreas de pastagem e no controle biológico de moscas de importância veterinária. D. gazella apresenta preferência por habitats abertos e ensolarados e de vegetação herbácea, porém há indícios de que esta vem se adaptando a áreas fechadas. Com isso, este estudo objetivou avaliar a capacidade de D. gazella em se desenvolver em ambiente florestal. O estudo foi realizado nos anos de 2012 e 2013 na Fazenda de Pesquisa e Extensão da UNESP - campus de Ilha Solteira, em Selvíria/MS. Para avaliar a presença de D. gazella na mata foram utilizadas armadilhas pitfall e para verificar a capacidade de desenvolvimento um casal da referida espécie foi mantido no pasto e no fragmento florestal na ausência e presença de competidores. Os resultados indicam que D. gazella é capaz de entrar no fragmento florestal, porém a curtas distâncias da borda. E que de forma geral os indivíduos desta espécie não são capazes de se desenvolverem e se estabelecerem no fragmento florestal

ATLANTIC ANTS: a data set of ants in Atlantic Forests of South America

International audienc