Effects of bait spacing on ant abundance and richness in one forest at Central Amazonia

• Published in: Acta amazonica 2011-03, Vol.41 (1), p.115-122
• Main Authors: Baccaro, F B, Ketelhut, S M, de Morais, JW
• Format: Article
• Language: Portuguese
• Subjects: Formicidae
• ISSN: 0044-5967

Baits are widely used to investigate the activity of terrestrial and arboreal ants, but also can be used to estimate the ant abundance and species richness. Despite the fact that baiting are cheap and easy to implement, many factors, such as the distance between baits, may influence the estimate of ant species richness and abundance. In this study, we evaluated the effects of bait spacing on abundance and the number of ant species. We also demonstrate which distance between baits showed the best relationship between costs and number of ant species sampled. We sampled 30 transects of 100 m with bait spacing ranging from 2.5 to 20 m, spread over 1 km super(2) of a "terra-firme" forest situated at North of Manaus. The bait spacing did not affect the ant diversity estimative. Regardless bait spacing, the number of species collected every five baits was around 8, and the average abundance was approximately 50 individuals. However the number of species per bait was higher in transects with larger bait spacing. Transects with bait spacing of 10 m and 20 m, collected 50% more species than transects with baits placed 2.5 m and 3.4 m apart. Our results suggest that at this forest, the most efficient sampling design using only baits would be place 450 baits every 10 m or 20 m at the forest floor.Original Abstract: Coletas com iscas sao amplamente utilizadas para investigar a atividade de formigas de solo e vegetacao e tambem podem ser empregadas para estimar o mimero de especies e a abundancia de formigas. Apesar de ser barata e facil de implementar, a riqueza e abundancia das formigas estimadas por iscas podem ser enviesadas por alguns fatores, como a distancia entre iscas. Neste trabalho, avaliamos se a distancia entre iscas altera as estimativas de abundancia e riqueza de formigas e qual distancia entre iscas resulta na melhor relacao entre custo financeiro e niimero de especies amostradas, objetivo da maioria dos relatorios de impacto ambiental. Amostramos 30 transectos de 100 m com distancia entre iscas diferentes (2,5; 3,4; 5; 6,7; 10 e 20 m), distribufdos em uma area de 1 km super(2) em uma floresta de terra-firme ao norte de Manaus. Independente da distancia entre iscas, o mimero de especies coletado a cada cinco iscas, foi aproximadamente 8, e a abundancia media foi maior que 50 individuos. No entanto o mimero de especies por isca foi maior em transectos com maior distancia entre iscas. Transectos com distancia entre iscas de 10 e 20 m, coletaram 50% mais es