Efficiency of playback for assessing the occurrence of five bird species in Brazilian Atlantic Forest fragments

Abstract

Playback of bird songs is a useful technique for species detection; however, this method is usually not standardized. We tested playback effi ciency for fi ve Atlantic Forest birds (White-browed Warbler Basileuterus leucoblepharus, Giant Antshrike Batara cinerea, Swallow-tailed Manakin Chiroxiphia caudata, Whiteshouldered Fire-eye Pyriglena leucoptera and Surucua Trogon Trogon surrucura) for different time of the day, season of the year and species abundance at the Morro Grande Forest Reserve (South-eastern Brazil) and at thirteen forest fragments in a nearby landscape. Vocalizations were broadcasted monthly at sunrise, noon and sunset, during one year. For B. leucoblepharus, C. caudata and T. surrucura, sunrise and noon were more effi cient than sunset. Batara cinerea presented higher effi ciency from July to October. Playback expanded the favourable period for avifaunal surveys in tropical forest, usually restricted to early morning in the breeding season. The playback was effi cient in detecting the presence of all species when the abundance was not too low. But only B. leucoblepharus and T. surrucura showed abundance values signifi cantly related to this effi ciency. The present study provided a precise indication of the best daily and seasonal periods and a confi dence interval to maximize the effi ciency of playback to detect the occurrence of these forest species.

Targeted reforestation could reverse declines in connectivity for understory birds in a tropical habitat corridor

“…Songs were played at the average measured volume for our four bird species (~80 db at 1 m; see Boscolo et al. ). When a bird responded to the song playbacks, the researchers retreated >5 m from the speaker, crouched, and played the species’ song until an individual approached the forest edge, for a maximum of 10 min.…”

Fragment edge and isolation affect the food web: effects on the strength of interactions among trophic guilds

“…We obtained owl species richness estimates using playbacks (Boscolo et al 2006) and visual identification of species whenever possible. Eight owl species, known to occur in the study area (Sigrist 2006), were selected a priori: Glaucidium minutissimun, Glaucidium brasilianum, Strix virgata, Strix hylophila, Pulsatrix koeniswaldiana, Bubo virginianus, Athene cunicularia, and Megascops choliba.…”

Isolation determines patterns of species presence in highly fragmented landscapes

“…All species are non‐migratory year‐round residents with strong territorial behaviour and known to actively respond to playback stimuli (Stotz et al 1996). Two of them ( C. caudata and P. leucoptera ) have already been studied for several years in the selected landscapes (Uezu et al 2005, Boscolo et al 2006, Awade and Metzger 2008). Precise and efficient playback methods for their census have been tested and consolidated (Boscolo et al 2006), what reduces the problems of imprecise presence detection.…”

“…If after this three days period no bird was heard or seen within the patch, that species' presence probability was considered to be very low (e.g. <5%; Boscolo et al 2006), and the species was noted as absent at that location.…”