Spatial partitioning of perching on plants by tropical dung beetles depends on body size and leaf characteristics: a sit-and-wait strategy for food location

[1.] Many animals invest a great amount of time and energy foraging.However, the sit-and-wait strategy is a common behaviour, which reduces the cost of moving by using perches. In the case of dung beetles, individuals of many species use leaves as perches. The factors for the selection of these perches are still unknown, but one hypothesis proposes that plant features may be key, creating an ecological animal–plant network.[2.] We identified dung beetles and plant species in a tropical rain forest and measured the height and area of the leaves, and the body length for each species. We fitted linear regression models to test the relationship between the height and area of the leaf and a beetle’s body size. We also analysed the number of perching interactions through a bipartite analysis to quantify the network modularity.[3.] We collected 369 dung beetles of 21 species that were perching on 32 plant species.There were significant differences in the selection of perches related to dung beetle body size and functional group. Larger beetle species selected higher and larger leaves, whereas telecoprids perched on higher leaves than paracoprids.[4.] Our findings show a distinct network of beetle-plant relationships with clear preferences by some dung beetles for particular plant species. The findings also suggest that the processes driving network structure lead to spatial segregation of dung beetle species. In conclusion, sit-and-wait behaviour is a common and apparently effective strategy for foraging, and reduces competition in dung beetles in tropical rain forests.JAN was supported by a Colombian COLCIENCIAS PhD scholarship and MMS was supported by an FPI PhD Grant (BES-2013-062910 from the CGL2012-32459 project)