Living on the edge: The use of fruit‐feeding butterflies to evaluate edge effect on subtropical assemblages

• Published in: Austral ecology 2023-04, Vol.48 (2), p.217-232
• Main Authors: Bellaver, Juliane, Romanowski, Helena Piccoli, Richter, Aline, Iserhard, Cristiano Agra
• Format: Article
• Language: English
• Subjects: Atlantic Forest; Butterflies & moths; Composition; conservation; Deforestation; diversity; Edge effect; Feeding; Forests; fragmentation; Fragments; Fruits; Habitat fragmentation; Habitats; Humidity; Indoor environments; Luminosity; Sampling; Temperature effects; turnover; Wind speed
• ISSN: 1442-9985; 1442-9993
• DOI: 10.1111/aec.13261

This study evaluated how the edge effect influences the structuration of fruit‐feeding butterfly assemblages in swamp forest fragments of the subtropical Atlantic Forest, Southern Brazil. Sampling was carried out twice in 10 fragments using baited traps placed in sampling units both at the forest edge and 50 m within the forest interior, with the habitats being defined by a set of environmental variables. Richness and abundance were higher for edge habitats with an effect of temperature depending on humidity and luminosity. The subfamily/tribe composition of fruit‐feeding butterflies was segregated between edge and interior and was predicted by wind speed and the interaction between humidity and luminosity. Fifty meters within the forest interior is not sufficient to cause homogenization of butterfly composition between the edge and interior of swamp forest fragments, indicating distinct assemblages in each habitat. The interior harboured forest‐loving butterfly groups while the edge harboured generalist sun‐loving and common butterflies associated with disturbed areas, suggesting resistance to the effects of habitat fragmentation. We highlight the importance of using fruit‐feeding butterfly groups, instead of species, to evaluate edge effects. We also suggest that a heterogeneous matrix with native habitats and distinct semi‐natural land‐use systems be maintained to manage subtropical areas by increasing connectivity within the landscape. Considering the impacts that the Atlantic Forest suffers, increased knowledge of modifications caused at small and regional scales is crucial for the maintenance of ecological processes and represents a tool for conservation planning and environmental agendas.