Regional distribution patterns can predict the local habitat specialization of arachnids in heterogeneous landscapes of the Atlantic Forest

Abstract

Aim This study formally evaluates the ability of three models to use geographical data on species distribution to predict the habitat use patterns of species in heterogeneous landscapes. Location Species and habitats in the Brazilian Atlantic Rain Forest were investigated. Methods Based on empirical data on harvestmen and scorpions, we estimated the strength of species association with preferred habitat and classified them as habitat generalists or habitat specialists. We compared these empirical results with predictions made using data on species range size (model 1), species occurrence in biomes (model 2) and species occurrence in habitats within the biomes (model 3). Results We used 1,278 records of eight harvestman and two scorpion species that had specific determination and enough sampling numbers to allow safe identification of habitat specialization. We observed the following: (1) the extension of species occurrence did not influence the strength of species–habitat association (estimated by IndVal), which led us to reject model 1; (2) species habitat specialization derived from occurrences in biomes was 60% coincident with the classification derived from empirical data. This value is not different enough from the value expected by chance for these data, which also led us to reject model 2; and (3) species classification derived from secondary data about the habitats used had a significant coincidence of 80% with the empirical classification, which led us to accept model 3. Main conclusions For correct classification of species habitat specialization using secondary distributional data, we recommend that future studies consider using the most accurate information available on the habitats used by species. Especially for megadiverse and understudied groups, information about habitats used is not easy to obtain, so it is important for researchers and institutions to register and disseminate this information, which could support many other studies.

Unraveling the Effects of Hurricane Maria on the Abundance and Composition of Harvestmen (Arachnida: Opiliones) Species Along an Elevational Gradient in Puerto Rico

“…Porto et al (2018) observed that most har-vestmen taxa had a limited geographic range and were closely tied to specific habitats. Out of the abundant species they sampled, three quarters were forest specialists, and the remainder specialized in open areas (Porto et al 2018). Thus, habitat type and microhabitat can have major proximal effects on harvestmen abundance and species composition.…”

“…However, they observed substantial differences between harvestmen taxa inhabiting the ground/litter layer and those inhabiting the shrub/tree layer, indicating specific habitat and microhabitat preferences within a forest stand (Proud et al 2012). Porto et al (2018) observed that most harvestmen taxa had a limited geographic range and were closely tied to specific habitats. Out of the abundant species they sampled, three quarters were forest specialists, and the remainder specialized in open areas (Porto et al 2018).…”

Diferentes distúrbios antrópicos na paisagem podem influenciar padrões florísticos e estruturais da Mata Atlântica?

“…Homepage:https://periodicos.ufpe.br/revistas/rbgfe Paschoal., E., M.., A., D., Otoni., T., J., O., Gripp., A., M., Freire., J., P., Alves., P., L., Gonzaga., A., P., D., Machado., E., L., M. principais ameaças a biodiversidade (Xie et al, 2017;Santos et al, 2020). Os fragmentos remanescentes, por possuírem áreas de habitat menores, acabam suportando populações também menores, e onde os riscos de extinção são mais comuns (Porto et al, 2018). Isto porque o isolamento das populações leva à depreciação do fluxo gênico, aumento da endogamia e perda da heterozigose, favorecendo a ocorrência da extinção local ou até mesmo regional (Porto et al, 2018;Cruz et al, 2018).…”

“…Os fragmentos remanescentes, por possuírem áreas de habitat menores, acabam suportando populações também menores, e onde os riscos de extinção são mais comuns (Porto et al, 2018). Isto porque o isolamento das populações leva à depreciação do fluxo gênico, aumento da endogamia e perda da heterozigose, favorecendo a ocorrência da extinção local ou até mesmo regional (Porto et al, 2018;Cruz et al, 2018). Tais consequências são ainda mais preocupantes quando ocorrem em ambientes que apresentam fragilidade ambiental, ou seja, quando os recursos naturais têm sido explorados durante séculos, incluindo, por exemplo, a ocupação antrópica na região da Mata Atlântica, o que proporcionou modificações na paisagem em larga escala e fragmentação florestal (Santos et al, 2020;Laurance, 2009;Ribeiro et al, 2009).Os altos níveis de fragmentação ainda observados atualmente, assim como, a contínua perda de habitat em toda a Mata Atlântica, têm gerado várias preocupações na comunidade científica (Joly et al, 2014;Esser et al, 2019).…”

A weighting method to improve habitat association analysis: tested on British carabids

“…Large-scale analysis of habitat association de-emphasises the less frequent recordings of a species in a habitat in which the species is transient, which could be misconstrued at a small-scale as association. Although SDMs (Petit et al 2003, Phillips et al 2006, Porto et al 2018) and indicator species analyses (Hill et al 1975, Gardner 1991, Ricotta et al 2015 are often done over large scales, this is rare for analysis of the preference of a species. Exceptions are Eyre and Luff (2004), who used ordination to study habitat preferences of carabids in north east England and the Scottish Border, and Redhead et al (2016) who used general linear mixed effects models to study butterfly habitats across Britain.…”