AUTHORS: Thanchira Suriyamongkol, Southern Illinois University; Brent Pease, Southern Illinois University; James Zaczek, Southern Illinois University; Jon Schoonover, Southern Illinois University; Clayton Nielsen; Southern Illinois University; John Groninger, Southern Illinois University
ABSTRACT: Destruction of wetlands reduced vegetation cover and habitat structures, which negatively impacted herpetofauna populations. Giant cane (Arundinaria gigantea) forms dense monodominant patches (canebrakes), once a prominent wetland feature throughout the lower Mississippi Valley. Although high herpetofauna richness is associated with landscape where canebrakes remain abundant, specific relationships between herpetofauna and canebrakes remain poorly studied. We conducted herpetofauna inventory and evaluated the influence of giant cane on herpetofauna richness and habitat use from April to June, 2022 and 2023 at 64 sites in southwestern Illinois, USA, using area search method. We detected 225 individual herpetofauna of 24 species, with17 species in canebrakes and 22 species in non-canebrakes. We examined differences in herpetofauna richness and communities between canebrakes and non-canebrakes using an analysis of variance (ANOVA) and a non-metric multidimensional scaling (NMDS) based on Bray-Curtis dissimilarity. We also assessed the occupancy probabilities of herpetofauna using a community occupancy model. Species richness was not significantly different between canebrakes and non-canebrakes (p = 0.42). The NMDS analysis revealed no differences in herpetofauna community between canebrakes and non-canebrakes. However, frogs (e.g., Hyla spp. and Lithobates spp.) were more commonly in areas with dense canebrake and herbaceous cover, while reptiles and salamanders (e.g., Eurycea spp. and Plethodon spp.) were associated with contiguous forest cover. Overall herpetofauna occupancy increased in areas with 1) increased canebrake density, 2) more canopy closure and tree density, 3) less ground vegetation cover, and 4) farther from road, forest edge, agriculture, and open water source. Current canebrakes structure, which are sparse and fragmented, might explain the lack of strong influence of canebrake on herpetofauna communities. However, variations in the relationship patterns between herpetofauna and other habitat components were expected given diverse life histories among species. Therefore, maintaining habitat heterogeneity and managing other microhabitat components in wetlands are important for conservation of herpetofauna.
