Back to Search Start Over

Patterns of resource partitioning by nesting herons and ibis: How are odonata exploited?

Authors :
Abdennour Boucheker
Boudjéma Samraoui
Riad Nedjah
Farrah Samraoui
Ahmed H. Alfarhan
Source :
Comptes Rendus Biologies. 335:310-317
Publication Year :
2012
Publisher :
Elsevier BV, 2012.

Abstract

Herons and ibis are colonially nesting waders which, owing to their number, mobility and trophic role as top predators, play a key role in aquatic ecosystems. They are also good biological models to investigate interspecific competition between sympatric species and predation; two processes which structure ecological communities. Odonata are also numerous, diverse, mobile and can play an important role in aquatic ecosystems by serving as prey for herons and ibis. A relationship between prey size and bird predator has been observed in Numidia wetlands (NE Algeria) after analyzing food boluses regurgitated by six species of birds (Purple Heron, Black-crowned Night Heron, Glossy Ibis, Little Egret, Squacco Heron and Cattle Egret) during the breeding period, which also shows a temporal gradient for the six species. Both the Levins index and preliminary multivariate analysis of the Odonata as prey fed to nestling herons and ibis, indicated a high degree of resource overlap. However, a distinction of prey based on taxonomy (suborder and family) and developmental stage (larvae or adults) reveals a clear size dichotomy with large-sized predators (Purple Heron, Black-crowned Night Heron and Glossy Ibis) preying on large preys like Aeshnids and Libellulids and small-sized predators feeding mainly on small prey like Zygoptera. Overall, the resource utilization suggests a pattern of resource segregation by coexisting nesting herons and ibis based on the timing of reproduction, prey types, prey size and foraging microhabitats.

Details

ISSN :
16310691
Volume :
335
Database :
OpenAIRE
Journal :
Comptes Rendus Biologies
Accession number :
edsair.doi.dedup.....8daf8eee26e48f6cd9649a950f7d30bb
Full Text :
https://doi.org/10.1016/j.crvi.2012.03.009