Highly disparate bird assemblages in sugarcane and pastures: implications for bird conservation in agricultural landscapes

Abstract

Sugarcane and cattle pastures are two of the most widespread and economically important agricultural landscapes. However, in Brazil, they have not been properly investigated for their importance to native birds and wildlife conservation. Thus, we aim to characterize and compare bird assemblages of sugarcane and cattle pastures; and understand how landscape features within both habitats influence bird assemblages. We surveyed birds in both agricultural habitats over one year, and then investigated the relationship between species richness and composition with landscape diversity, matrix permeability, and the size and distribution of natural forests close to both habitats. We observed 132 species in cattle pastures and only 72 in sugarcane (48% bird community similarity). We further evaluated the richness and relative abundance of avian ecological groups, including habitat specialists and habitat generalists, insectivores, omnivores, granivores and frugivores. All avian groups were higher in pastures, the habitat where landscape heterogeneity and number of scattered trees was higher. Our results show that overall increasing landscape heterogeneity favors an assemblage with higher richness and composed by species with more diverse ecological functions. Therefore, we argue in favor of management practices that incorporate heterogeneity in agricultural landscapes, mainly in sugarcane fields where a homogeneous scheme has been used. Otherwise, the potential of agricultural landscapes for bird conservation will be highly hindered, particularly if the sugarcane sector expands to other agricultural lands.

Can guava monocultures (Psidium guajava L.) function as refuge for bird conservation?

“…It was also lower than that of Tejeda-Cruz and Sutherland (2004) (n = 80 species) and Leyequién et al (2010) (n = 181 species), in coffee plantations. On the other hand, the number of bird species recorded in this study was higher than that recorded in Campolim (2011) (n = 57 species), in orchards of Citrus reticulata; (n = 42 species) and Almeida et al (2016) (n = 58 species), in oil palm plantations; Mangan et al (2017) (n = 59 species), in apple orchards; and in Alexandrino et al (2019) (n = 72 species), in sugarcane fields. Some of the bird species observed in guava orchards, such as Crypturellus parvirostris, Bubulcus ibis, Vanellus chilensis, Columbina talpacoti, Crotophaga ani, Furnarius rufus, Pitangus sulphuratus, Tyrannus melancholicus, Troglodytes musculus, Tangara sayaca, Volatinia jacarina and Euphonia chlorotica, were common to the studies by Estrada and Estrada (1997), Tejeda-Cruz and Sutherland (2004), Torresan (2010), Campolim (2011), Silva-Andrade (2016).…”

“…Although birds have been surveyed in various agricultural crops worldwide (e.g., Bennett et al 2006;Fischer et al 2008;Fahrig et al 2011), Brazilian crops have been poorly studied, despite Brazil's global importance for both agriculture and biodiversity (Alexandrino et al 2019). As a result, data on species occurrence and crop usage is scarce.…”

Remnants of Native Vegetation Surrounding Do Not Affect the Diversity and Density of Birds in Brazilian Grassland-Restoration Sites

“…We then marked an outer buffer zone with a 1-km radius, surrounding the smaller buffer zone. We determined this buffer proportion because it encompasses the home ranges of most Neotropical songbirds (Lee and Carroll, 2014), and is sufficiently large for the birds to perceive as a landscape (Rodewald and Yahner, 2001), covering all environmental features (Alexandrino et al, 2019). We drew polygons of all land uses except native grassland inside the outer buffer zone for each site, using a 1:20,000-scale screen.…”

Avian Use of Agricultural Areas as Migration Stopover Sites: A Review of Crop Management Practices and Ecological Correlates

“…One third of all bird species have been recorded in agricultural areas (Şekercioglu et al, 2007) and avian use of primary temporary crops is well documented, particularly for certain crops such as sugarcane (Alexandrino et al, 2019) and rice (Elphick et al, 2010;Masero et al, 2011;Elphick, 2015). For birds, temporary primary crops can provide food in the form of seeds, the plants themselves, or vertebrates and invertebrates that live among the crops (Stafford et al, 2010).…”