Assessing the use of forest islands by parrot species in a neotropical savanna

• Published in: Avian conservation and ecology 2015-06, Vol.10 (1), p.11, Article art11
• Main Authors: Berkunsky, Igor, Simoy, María V., Cepeda, Rosana E., Marinelli, Claudia, Kacoliris, Federico P., Daniele, Gonzalo, Cortelezzi, Agustina, Díaz-Luque, José A., Friedman, Juan Mateo, Aramburú, Rosana M.
• Format: Article
• Language: English
• Subjects: Acrocomia aculeata; Attalea; Bolivia; habitat use; macaw; occupancy model
• ISSN: 1712-6568; 1712-6568
• DOI: 10.5751/ACE-00753-100111

Understanding the effect of habitat fragmentation is a fundamental yet complicated aim of many ecological studies. Beni savanna is a naturally fragmented forest habitat, where forest islands exhibit variation in resources and threats. To understand how the availability of resources and threats affect the use of forest islands by parrots, we applied occupancy modeling to quantify use and detection probabilities for 12 parrot species on 60 forest islands. The presence of urucuri (Attalea phalerata) and macaw (Acrocomia aculeata) palms, the number of tree cavities on the islands, and the presence of selective logging, and fire were included as covariates associated with availability of resources and threats. The model-selection analysis indicated that both resources and threats variables explained the use of forest islands by parrots. For most species, the best models confirmed predictions. The number of cavities was positively associated with use of forest islands by 11 species. The area of the island and the presence of macaw palm showed a positive association with the probability of use by seven and five species, respectively, while selective logging and fire showed a negative association with five and six species, respectively. The Blue-throated Macaw (Ara glaucogularis), the critically endangered parrot species endemic to our study area, was the only species that showed a negative association with both threats. Monitoring continues to be essential to evaluate conservation and management actions of parrot populations. Understanding of how species are using this natural fragmented habitat will help determine which fragments should be preserved and which conservation actions are needed.Original Abstract: La comprehension de l'effet de la fragmentation de l'habitat est l'objectif fondamental mais complique de nombreuses recherches en ecologie. La savane de Beni est un milieu forestier naturellement fragmente dans lequel les iles forestieres different sur le plan des ressources et des menaces. Afin de comprendre a quel point la disponibilite des ressources et les menaces ont une influence sur l'utilisation d'iles forestieres par les perroquets, nous avons applique des modeles de presence pour quantifier l'utilisation et la probabilite de detection de 12 especes de perroquets sur 60 iles forestieres. La presence de palmiers canne (Acrocomia aculeata) et de palmiers urucuri (Attalea phalerata), le nombre de cavites d'arbres sur les iles et la presence de coupes