Bats, Cache River National Wildlife Refuge, Bioacoustics, BCID, Arkansas, Bottomland Hardwood Forests, Occupancy, Program PRESENCE
Six bat species of special concern, threatened or endangered, may occur in one of Arkansas’ largest bottomland hardwood forests, the Cache River National Wildlife Refuge (CRNWR). However, inventory of bat species throughout the refuge has been lacking and management plans may not be adequate in promoting bat conservation. The objectives of this study were to inventory bat species in the CRNWR, and determine bat-habitat associations via occupancy estimates. From May–August 2014 and 2015, we mist-netted from sunset for 5 hours. We also deployed bioacoustic devices throughout 5 habitat types (cypress-tupelo [dominantly Taxodium distichum and Nyssa aquatica], emergent wetland, mature forest, hardwood reforestation, and managed hardwood). Mist-netting yielded 460 bat captures with Rafinesque’s big-eared bats (Corynorhinus rafinesquii; n = 156) being the most common capture, followed by eastern red bats (Lasiurus borealis; n = 104), southeastern myotis (Myotis austroriparius; n = 91), evening bats (Nycticeius humeralis; n = 58), tri-colored bats (Perimyotis subflavus; n = 54), and a big-brown bat (Eptesicus fuscus; n = 1). Based on 3,896 calls identified with 85% certainty, evening bats and rarer big-brown bats tended to occupy managed hardwood forests more than any other habitat (occupancy probabilities ± SE: Ψ = 0.75 ± 0.13 and 0.38 ± 0.19, respectively). Tri-colored bats tended to be more present in mature forest habitats (Ψ = 0.91 ± 0.09), and Myotis species tended to have highest occupancy rates in cypress-tupelo stands (Ψ = 0.59 ± 0.15). Not all species were detected with both methods. Thus, we encourage future studies to combine mist-netting and acoustic surveying methods to minimize bias in species presence estimate. This would ensure management practices that would benefit all present species.
Schratz, Samuel; Rolland, Virginie; Phillips, Jason; Crossett, Richard; Richardson, David; and Risch, Thomas S.
"Bat Occupancy Estimates and Species Richness at Cache River National Wildlife Refuge,"
Journal of the Arkansas Academy of Science: Vol. 71
, Article 20.
Available at: http://scholarworks.uark.edu/jaas/vol71/iss1/20