Distribution of Bats in Bottomland Hardwood Forests of the Arkansas Delta Region

Bat distribution data is incomplete for the delta region of Arkansas. We extensively surveyed 16 counties within the Mississippi alluvial plain that comprises the delta from late spring to early fall 2004 using mist nets. We obtained 44 new county records for 9 species: Myotis lucifigus, M. austroriparius, Pipistrellus subflavus, Eptesicus fuscus, Lasiurus seminolus, L. borealis, L. cinereus, Nycticeius humeralis, and Corynorhinus rafinesquii. We generated updated distribution maps for these species and eastward Arkansas range expansions were documented for L.seminolus. Possible sampling concerns and research directions are discussed in relation to the needs of bats inhabiting bottomland forests of the delta, particularly M. austroriparius and C. rafinesquii

Perch-type Characteristics of Overwintering Red-tailed Hawks (Buteo jamaicensis) and American Kestrels (Falco sparverius)

Red-tailed Hawks (Buteo jamaicensis) and American Kestrels (Falco sparverius) are primarily sitand-wait predators that rely on perches to forage most efficiently. Overwintering Red-tailed Hawks and American Kestrels use available perches (e.g., utility poles and wires, trees, fences, gates, etc.) to hunt for prey items in agricultural fields in northeast Arkansas. Observations were made from December 2011-March 2012 and November 2012-March 2013 in three representative cover-types (short rice stubble, soybean stubble, and fallow areas including roadsides) to determine which perch-types were used by Red-tailed Hawks and American Kestrels. Utility pole crossbeams at an average height of 6.3 m were the main perchtypes used by Red-tailed Hawks, demonstrating the use of man-made structures’. These perches were generally in or near fallow areas or short rice stubble fields. Conversely, American Kestrels usually perched on wires at an average height of 4.9 m, over fallow roadsides’. Fallow areas had high prey density and vegetation cover. Niche separation via differential use of perches may be one factor that allows these raptors to avoid inter-specific competition

Amphibian, Reptile, and Small Mammal Associates of Ozark Pocket Gopher Habitat in Izard County, Arkansas

We conducted a study of the amphibian, reptile, and small mammal community assemblage of Ozark pocket gopher (Geomys bursarius ozarkensis) habitat in north-central Arkansas. We used 2 methods to capture individuals: hand capture and drift fences. During the study, we captured and marked a total of 9 anuran, 4 salamander, 5 lizard, 3 turtle, 16 snake, and 8 small mammal species exclusive of pocket gophers. We found one hatchling three-toed box turtle (Terrapene carolina triunguis) and one rough earth snake (Virginia striatula) inside a pocket gopher burrow and mound, respectively. Additionally, we witnessed both eastern racers (Coluber constrictor) and eastern coachwhips (Masticophis flagellum) retreat into pocket gopher burrows, as well as Hurter’s spadefoots (Scaphiopus holbrookii hurterii) burrow into pocket gopher mounds when released. Our results highlight the importance of mammalian burrows, specifically pocket gophers, to other vertebrate associates in grassland ecosystems. Both conservationists and managers need to determine the pocket gopher’s impact on ecosystem health and viability, specifically in natural grasslands, before conservation and/or management strategies are employed

Responses of Bats to Forest Fragmentation in the Mississippi River Alluvial Valley, Arkansas, USA

Intense conversion of bottomland hardwood forests to rice and soybeans in the Mississippi River Valley of Arkansas has restricted the remaining forest to isolated fragments. Habitat fragmentation has proven to be detrimental to population sustainability of several species, and is the subject of intense study with often species and latitude specific responses. We compared both coarse land area classes and landscape fragmentation metrics from six 30 km × 30 km subsets centered on publicly owned management areas to bat captures obtained from a 2005 population study. Patch density was the strongest predictor of total captures (R 2 = 0.801, p = 0.016) and of Myotis austroriparius captures (R 2 = 0.856, p = 0.008). Our findings indicate that patch density and area are important predictors of bottomland bat captures

Bat Occupancy Estimates and Species Richness at Cache River National Wildlife Refuge

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