Aquatic insects indicate terrestrial habitat degradation: changes in taxonomical structure and functional diversity of dragonflies in tropical rainforest of East Kalimantan

Abstract

As a group of freshwater invertebrates, dragonflies (Odonata) are commonly used as ecological indicators of freshwater ecosystems. Despite earlier studies suggesting that adult odonates may be good indicators for complex changes in a landscape, the utility of odonates as suitable indicators to indicate health of non-aquatic (forest) habitats remains poorly understood. This study analyses the adult dragonfly assemblage pattern against spatial and temporal disturbance characteristics in Indonesia's Sungai Wain Protection Forest. The core of this reserve comprises one of the few remaining fragments of primary rain forest along the East Kalimantan coast, whereas the rest of the reserve is covered by secondary forest, scrub, grassland, and farmland. Adult dragonfly assemblages at individual sampling sites were analysed in relation to (1) their intensity, (2) frequency of human-caused disturbances, and (3) the time since the last such disturbance, while controlling random variables (type of aquatic and terrestrial habitat) were removed. This study tests the effect of these factors on (1) species richness, (2) proportion of Zygoptera, (3) proportion of forest specialists, and (4) proportion of Borneo's endemics. The humaninduced disturbances in the rain forest resulted in pronounced changes in the taxonomical composition and functional diversity of the odonate fauna. Results reported here demonstrate that gradual changes in the odonate assemblages correspond to the degree of anthropogenic influences on forest environments. Adult odonates comprise an appropriately sensitive and versatile indicator group for identifying changes in terrestrial forest environments as well as in freshwater habitats.

Home Range, Movement, and Distribution Patterns of the Threatened Dragonfly Sympetrum depressiusculum (Odonata: Libellulidae): A Thousand Times Greater Territory to Protect?

“…Our data support the concept of using dragonflies as indicators of freshwater habitat quality and changes in habitat quality [4], [38], [39]. In addition, our findings suggest that the structure of the surrounding landscapes (i.e.…”

Analysis of urban impacts on aquatic habitats in the central Amazon basin: Adult odonates as bioindicators of environmental quality

“…Many species are habitat specialists, being sensitive to changes in the environment, and may become extinct more than generalist species (Dolný et al, 2012;Suhonen et al, 2010). In the case of damselflies (Zygoptera), species diversity appears to be influenced primarily by environmental heterogeneity (McPeek, 2008), with more complex habitats favoring the establishment of larger numbers of species, given that these insects require riparian vegetation with perches due to their reduced dispersal capacity, as well as areas for foraging and reproducing, and to provide refuge from predators (Corbet, 1999;Johansson, 2000).…”

Setting boundaries: Environmental and spatial effects on Odonata larvae distribution (Insecta)

“…Thus, for some species, the niche conservatism and lack of ability of adapting to environmental changes are the key factors in explaining the loss of genetic variability and the residence of species in the environment (Wiens 2004, Wiens andGraham 2005). These environmental requirements are some of the characteristics that make Odonata sensitive to changes in the environment and thus widely used bioindicators (Dolný et al 2012). Therefore, we believe that for Zygoptera, dispersal rates followed by colonization events would modify both species abundance (patch -dynamic model) as well as interaction among species (Pulliam 1988 andLeibold et al 2004).…”

“…Perithemis, Micrathyria 245 SPACE OR ENVIRONMENT STRUCTURING ASSEMBLIES and Diastatops), although the determining effect was not strong enough to show significant effects on the Anisoptera suborder. However, Dolný et al (2012) showed the dependence of Zygoptera on habitat structure and its association to ecosystem characteristics making them specialist organisms and excellent habitat bioindicators. Thus, for some species, the niche conservatism and lack of ability of adapting to environmental changes are the key factors in explaining the loss of genetic variability and the residence of species in the environment (Wiens 2004, Wiens andGraham 2005).…”