1. Ecological restoration of riparian forest corridors at the landscape scale can facilitate recruitment of certain flora and fauna, thus possibly helping to maintain viable wildlife populations.2. We evaluated ecological restoration of three corridors between two protected Andean forests. Soil ants and eight environmental variables focused on edaphic conditions were monitored for 8 years following restoration activity. Soil ants were collected in pitfall traps and by leaf litter extraction on 21 plots classified into five types of habitat: large forest patches, riparian forests, two types of restoration corridors on former timber and pasture land (R-Forestry and R-Pasture, respectively), and Pasture.3. A total of 132 ant species belonging to 40 genera were found. Among these, 112 species were found in Forests, 105 in Riparian, 80 in R-Forestry, 79 in R-Pasture and 63 in Pasture. Composition analyses (canonical correspondence analysis and NMDS) showed that the ant community in restoration corridors and pastures is far from resembling that of the forests. Yet, there is biological progress with respect to the Pasture.4. Gnamptogenys bisulca and Pheidole pygmaea were indicator species for advanced restoration progress because of their close association to forests, while Linepithema piliferum indicated a reversal of restoration progress due to its preference for open habitats.5. Since both ant richness and composition in restored areas do not yet resemble the reference forest ecosystem, we suggest that other interventions such as restoring wider corridors and changing to wild-friendly agriculture around the reserves might improve restoration efforts in Andean landscapes.

Hunting ants are predators of organisms belonging to different trophic levels. Their presence, abundance, and diversity may reflect the diversity of other ants and contribute to evaluate habitat conditions. Between 2003 and 2005 the restoration of seven corridors in an Andean rural landscape of Colombia was performed. The restoration took place in lands that were formerly either forestry plantations or pasturelands. To evaluate restoration progress, hunting ants were intensely sampled for 7 yr, using sifted leaf litter and mini-Winkler, and pitfall traps in 21 plots classified into five vegetation types: forests, riparian forests, two types of restored corridors, and pasturelands. The ant communities were faithful to their habitat over time, and the main differences in ant composition, abundance, and richness were due to differences among land use types. The forests and riparian forests support 45% of the species in the landscape while the restored corridors contain between 8.3-25%. The change from forest to pasturelands represents a loss of 80% of the species. Ant composition in restored corridors was significantly different than in forests but restored corridors of soil of forestry plantations retained 16.7% more species than restored corridors from pasturelands. Ubiquitous hunting ants, Hypoponera opacior (Forel) and Gnamptogenys ca andina were usually associated with pastures and dominate restored corridors. Other cryptic, small, and specialized hunting ants are not present in the restored corridors. Results suggest that the history of land use is important for the biodiversity of hunting ants but also that corridors have not yet effectively contributed toward conservation goals.

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