Species-richness, abundance, and body size of stream-breeding anurans across land-use types in Sabah, Malaysia (Borneo)

Abstract

Approximately 70% of Earth’s surface is impacted by human land-use. While numerous studies have demonstrated that species richness is higher in primary (undisturbed) forest than in secondary forest or agriculture sites, some studies fail to detect differences in species richness across land-use type. Recent work suggests that individual-level changes such as body size or body condition can occur more rapidly than population- or community-level processes, such as abundance and species richness, respectively. Thus, body size and condition may be more sensitive measures of environmental changes. We examined body size, body condition, abundance, and species richness of anurans in primary forest, secondary forest, and agriculture in Sabah, Malaysian Borneo, to determine whether individual-, population-, and community-level measures show similar sensitivities to land-use type. We found that observed anuran species richness and estimated population size are lower in agriculture than in primary or secondary forest, as were body size (SVL), mass, and body condition of female Meristogenys orphnocnemis. Further, anuran body condition (all species pooled) was higher in primary forest than agriculture or secondary forest, and size (SVL), mass, and body condition of male M. orphnocnemis were higher in primary forest than in agriculture or secondary forest areas. Collectively, our data demonstrate that primary forests are the best habitat for anurans in Sabah, and that individual-level processes such as size, mass, and body condition, show larger differences across land-use type than population- (abundance) or community-level processes (species richness). These data highlight the importance of primary forest for preserving anuran biodiversity in Borneo.

Keywords

• Agriculture
• Body condition
• Frogs
• Primary forest
• Secondary forest