Managing the farmscape for connectivity increases conservation value for tropical bird species with different forest-dependencies.

Land clearing for agricultural use is a primary driver of biodiversity loss and fragmentation of natural ecosystems. Restoring natural habitat connectivity by retaining quality habitats and increasing on-farm tree cover contributes to species' mobility and persistence in agricultural landscapes. Nonetheless, remarkably few studies have quantified the impacts of on-farm practices for species' mobility measured as functional connectivity within the context of farm and broader spatial levels of landscape organization. We tested how adding and removing trees in different configurations on a farm comprised of coffee plantations and cattle pastures can help evaluate species' mobility at the farmscape level (an area comprising the farm plus a 1.5 km buffer area). We coupled bird capture data and scenario modeling to assess species mobility of five neotropical bird species with distinct life history characteristics representing a gradient of forest dependency. We used seven years of mist-netting data to estimate species habitat affinity and to predict species mobility using the Circuitscape model across a 4371 ha farmscape in Costa Rica. Circuitscape allowed us to estimate changes in movement probability and relative changes in resistance to movement that species experience during dispersal (measured as resistance distance and passage area through which species can move) under four farmscape management scenarios. The four land-use scenarios included: (a) the 2011 farmscape land-use composition and configuration, b) converting all existing live fences to post-and-wire fence lines in the farm c) converting simplified coffee agroforests to multistrata coffee agroforests in the farm, and d) placing multistrata live fences around the perimeter of every parcel and roads on the farm. Model results suggest that existing multistrata live fences maintain the sporadic movement of all five species irrespective of forest dependence. Likewise, adding multistrata live fences around individual fields presents a more efficient strategy for increasing species mobility than multistrata coffee agroforestry systems in the assessed farmscape, by doubling the passage areas available to all species, although it created labyrinths with "dead-ends" for two species. While retaining large habitat patches remains important for conservation, managing on-farm connectivity complements these efforts by increasing movement probability and reducing dispersal resistance for forest-dependent bird species.

Landscape connectivity among remnant populations of guanaco (Lama guanicoe Müller, 1776) in an arid region of Chile impacted by global change.

Connectivity between populations plays a key role in the long-term persistence of species in fragmented habitats. This is of particular concern for biodiversity preservation in drylands, since water limited landscapes are typically characterized by little suitable habitat cover, high habitat fragmentation, harsh matrices, and are being rapidly degraded at a global scale. In this study, we modelled landscape connectivity between 11 guanaco Lama guanicoe populations in Chile's arid Norte Chico, a region that supports the last remnant coastal populations of this emblematic herbivore indigenous to South America. We produced a habitat suitability model to derive a regional surface resistance map, and used circuit theory to map functional connectivity, investigate the relative isolation between populations, and identify those that contribute most to the patch connectivity network. Predicted suitable habitat for L. guanicoe represented about 25% of the study region (i.e., 29,173 km2) and was heterogeneously distributed along a continuous stretch along the Andes, and discontinuous patches along the coast. As a result, we found that high connectivity current flows in the mid and high Andes formed a wide, continuous connectivity corridor, enabling connectivity between all high Andean populations. Coastal populations, in contrast, were more isolated. These groups demonstrate no inter-population connectivity between themselves, only with higher altitude populations, and for two of them, animal movement was linked to the effectiveness of wildlife crossings along the Pan-American highway. Our results indicate that functional connectivity is an issue of concern for L. guanicoe in Chile's Norte Chico, implying that future conservation and management plans should emphasize strategies aimed at conserving functional connectivity between coastal and Andean populations, as well as the protection of habitat patches likely to act as stepping stones within the connectivity network.