Effect of Habitat and Foraging Height on Bat Activity in the Coastal Plain of South Carolina

Abstract

M7e conipared bat activity levels in the Coaslal Plain of South Carolina atnong 5 habitat types: forested riparian areas, clearcuts, young pine plat~tations, mature pine plantations, and pine savannas. We used time-expansion I-adio-microphones and integrated detectors to simultaneously monitor bat activity at 3 heights (30, 10, 2 mj in each habitat type. Variation in vegetative clutter among sanipling heights and arnttng habitat types allowed us to examine the differential effect of forest vegetation on the spatial activity patterns of clutter-adapted and openadapted bat species. Moreover, monitoring activit~~ at 30, 10, and 2 m permitted us to also compare bat activity above and below the forest canopy. We detected calls of 5 species 01-species groups: eastern red/Seminole bats (Lasiums bo~-ealis/ L. seminol'us) , eastern pipistrelles (Pipistrellus subfivus) , evening bats (iz5cticpiu~ hu?nerulis), big brown bats (Eptesicus fuscus), and hoary bats (Lasiul-us cinrrius). At 2 and 10 m, bat activity was concentrated in riparian areas, whereas we detected relatively low levels of bat activity in upland habitats at those heights. Activity was more evenly distributed across the landscape at 30 m. Bat activity levels above the forest canopy were almost 3 times greater than within or below the canopy. We detected significantly greater activity levels of 2 open-adapted species (hoary and big brown bats) above rather than within or be lo^^^ the forest canopy. However, activity levels of 2 clutter-adapted species (eastern red,'Seminole bats and eastern pipistrelles) did not differ above, within, or below the forest canopy Despite classification as a clutter-adapted species, evening bat activity was greater above rather than within or below the forest canopy. We believe our results highlight the importance of riparian areas as foraging habitat for bats in pine-dominated landscapes in the southeastern United Slates. Although acoustical surveys conducted below forest canopies can provide useful intitmiation about species composition and relative activity levels of bats that forage in cluttered environments, our results sl~owing activity above canopy suggest that such data may not accurately reflect relative activity of bats adapted to forage in more open conditions, and therefore may provide an inaccurate picture of bat community assemblage and foraging habitat use. JOURNAL OF WILDLIFE MANAGEMENT

Habitat-associated and temporal patterns of bat activity in a diverse forest landscape of southern New England, USA

“…The diVerence in bat activity between harvested and uncut forest was most clearly seen in active acoustic surveys of large-bodied (open adapted) species, with larger numbers of bats recorded per unit time in the harvested sites and with the numbers increasing with cutting intensity (Table 3a). These results support the suggestion that the opening of the forest canopy creates additional uncluttered foraging habitat (Grindal and Brigham 1998;Owen et al 2004;Menzel et al 2005b). The eVect was less apparent for clutter-adapted Myotis species.…”

“…In this study, clutter eVects were addressed by surveying open-canopy sites, including both terrestrial (open Welds and clear cuts) and aquatic habitats (beaver meadows, ponds, and reservoir) and closed-canopy sites (partial and uncut forests, woods roads, streams, and seasonal forest pools). One major habitat that was not surveyed was the air space above forest canopies (Menzel et al 2000(Menzel et al , 2005b. Individual survey sites were subjectively chosen to best represent the desired habitat.…”

Distribution and activity of bats at local and landscape scales within a rural–urban gradient

“…Big brown bats, eastern red bats, and eastern pipistrelles were the most ubiquitous bat species throughout the landscape, occurring at all parks. This distribution may be attributed to their broad niche and generalist foraging behaviors and ability to migrate to all NCR Parks (Hutchinson and Lacki 1999;Ford et al 2005;Menzel et al 2005). Still, some variation in big brown bat activity did occur among parks.…”

Habitat preferences of bats in anthropogenically altered, mosaic landscapes of northern Poland

“…Many other studies indicate the exceptional significance of water bodies and riparian habitats for bat fauna in the temperate zone of the Holarctic (e.g. Vaughan et al 1997a;Menzel et al 2005;Vindigni et al 2009). It is usually associated with high abundance of flying insects, especially those undertaking their larval development in water (Fukui et al 2006).…”