1854 INTRODUCTION Changes in landscape attributes such as the amount of forest cover can alter species composition (Fahrig 2013, Dirzo et al. 2014) and are thought to be relevant to the maintenance of biodiversity and integrity of ecological processes. Moreover, species can respond idi- osyncratically to anthropogenic impacts. Thus, to better conserve or restore particular aspects of the contem- porary biota, it is imperative to determine which species in different taxonomic groups most respond to anthro- pogenic alterations and how they persist in fragmented environments (Sutherland et al. 2013). Information about ecological aspects such as community structure and species’ responses to landscape changes (Banks-Leite et al. 2014) can be obtained through examination of response curves to landscape characteristics, which are not always linear (Fahrig 2003). Based on such infor- mation, it may be possible to develop more efficient conservation strategies. Knowledge of effects of anthro- pogenic impacts on the contemporary biota has direct implications to defining strategies of landscape man- agement for conservation and habitat restoration (Rodrigues et al. 2009, Tambosi et al. 2013). Variation in habitat diversity, connectivity, and total amount of habitat have direct effects on species distribution and diversity within heterogeneous land- scapes (Estavillo et al. 2013). However, among these different landscape properties, quantity of remaining habitat is claimed to be the characteristic that best explains ecological responses related to ecosystem func- tions for many organisms (Fahrig 2013). Often there are threshold responses describing the relationship between amount of habitat and other biological Threshold effect of habitat loss on bat richness in cerrado-forest landscapes RENATA L. MUYLAERT, 1,3 RICHARD D. STEVENS, 2 AND MILTON C. RIBEIRO 1 1 Department of Ecology, Universidade Estadual Paulista (UNESP), 24A Av., 1515, 13506-900, Rio Claro, Brazil 2 Department of Natural Resources Management, Museum of Texas Tech University, Lubbock, Texas 79409 USA Abstract. Understanding how animal groups respond to contemporary habitat loss and fragmentation is essential for development of strategies for species conservation. Until now, there has been no consensus about how landscape degradation affects the diversity and distribution of Neotropical bats. Some studies demonstrate population declines and species loss in impacted areas, although the magnitude and generality of these effects on bat community structure are unclear. Empirical fragmentation thresholds predict an accen- tuated drop in biodiversity, and species richness in particular, when less than 30% of the original amount of habitat in the landscape remains. In this study, we tested whether bat species richness demonstrates this threshold response, based on 48 sites distributed across 12 landscapes with 9–88% remaining forest in Brazilian cerrado-forest formations. We also examined the degree to which abundance was similarly affected within four different feed- ing guilds. The threshold value for richness, below which bat diversity declines precipitously, was estimated at 47% of remaining forest. To verify if the response of bat abundance to habitat loss differed among feeding guilds, we used a model selection approach based on Akaike’s information criterion. Models accounted for the amount of riparian forest, sem- ideciduous forest, cerrado, tree plantations, secondary forest, and the total amount of forest in the landscape. We demonstrate a nonlinear effect of the contribution of tree plantations to frugivores, and a positive effect of the amount of cerrado to nectarivores and animalivores, the groups that responded most to decreases in amount of forest. We suggest that bat assemblages in interior Atlantic Forest and cerrado regions of southeastern Brazil are impoverished, since we found lower richness and abundance of different groups in landscapes with lower amounts of forest. The relatively higher threshold value of 47% suggests that bat communities have a relatively lower resistance to habitat degradation than other animal groups. Accordingly, conservation and restoration strategies should focus on increasing the amount of native vegetation of landscapes so as to enhance species richness of bats. Key words: cerrado; Chiroptera; conservation; environmental gradient; fragmentation threshold; habitat amount; interior Atlantic Forest; landscape resilience. Ecological Applications, 26(6), 2016, pp. 1854–1867 © 2016 by the Ecological Society of America Manuscript received 1 October 2015; revised 29 December 2015; accepted 1 January 2016; final version received 19 February 2016. Corresponding Editor: J. Goheen. 3 E-mail: renatamuy@gmail.com