Foraging guild structure and niche characteristics of waterbirds in an epicontinental lake in Mexico

Abstract

Background: It was suggested that ecological patterns can be used to infer the nature of ecological processes (i.e., competition) that structure communities. Analysis of patterns of resource partitioning under the classical niche paradigm (competitive niche differentiation in exploiting limited resources) has traditionally been used to understand the structure of communities. On the contrary, neutral theory states that patterns result from neutral processes such as stochasticity and dispersal abilities. Thus, if any ecological process gives rise to a characteristic ecological pattern, the comparative study of patterns with appropriate neutral models may reveal the magnitude of that process. In this study, we analyzed patterns of resource utilization of a waterbird community in Lake Acuitlapilco, an epicontinental lake in central Mexico. In February 2011 to January 2012, we recorded foraging behaviors of waterbird species in two niche dimensions or axes: feeding technique and foraging habitat. The pattern of resource utilization was characterized by niche breath and niche overlap. Results: Results showed that waterbird species in Lake Acuitlapilco were specialists in resource utilization patterns and therefore were vulnerable to fluctuations in resources, particularly feeding habitat. Niche overlaps were generally largest among species belonging to the same guild. To test competition as an ecological process that plays a role in the community structure, observed niche overlaps were compared with niche overlaps generated with null models of communities in the absence of competition using the RA4 randomization algorithm. Habitat and observed bidimensional overlaps were higher than those of randomly generated communities. Conclusions: Our study suggested that other processes can be used to predict resource utilization patterns instead of competition alone, as suggested by neutral theory. Future studies analyzing the mechanisms that structure waterbird communities should include the use of null models to support their conclusions.

Comparing habitat preferences of a set of waterbird species wintering in coastal wetlands of North Africa: implication for management

“…our findings suggest that, waterbird species inhabiting tonga wetland have certain similarity in using the different habitat categories, which leads to cluster them into 5 guilds. in ecology, guild is a group of species that exploit the same kinds of resources in comparable ways (ntiamoa-Baidu et al, 1996;Pérez-crespo et al, 2013;Liordos, 2010). accordingly, to the number of species in each guild and their levels of conservation concern, the seven studied microhabitats havecertain relevant differences in their importance for the citation species.…”

“…one of the principal factors that influence the structure of waterbird communities is the partitioning of resources (either food or space)and it may be driven by the large number of water-related variables affecting species interactions (Pérezcrespo et al, 2013). Most studies searching for patterns of resource utilization (food and space) evaluated niche breadth and niche overlap (krebs, 1999;Pérez-crespo et al, 2013). niche breadth is an important parameter forthe evaluation of the level of dietary specialization; species with niches of reduced breadth are relatively specialized, whereas more ample niches are typical of generalist species (colwell, Futuyma, 1971;krebs, 1999;Pérez-crespo et al, 2013).…”

“…Most studies searching for patterns of resource utilization (food and space) evaluated niche breadth and niche overlap (krebs, 1999;Pérez-crespo et al, 2013). niche breadth is an important parameter forthe evaluation of the level of dietary specialization; species with niches of reduced breadth are relatively specialized, whereas more ample niches are typical of generalist species (colwell, Futuyma, 1971;krebs, 1999;Pérez-crespo et al, 2013). The analysis of niche overlap also provides an important approach to answer the question: How do the different species partition the resources in the community?…”

“…The analysis of niche overlap also provides an important approach to answer the question: How do the different species partition the resources in the community? if species overlap in niches to a great extent, they may influence each other's population growth through interspecific competition (colwell, Futuyma 1971;krebs, 1999;Pérez-crespo et al, 2013).…”

Environmental and anthropogenic factors structuring waterbird habitats of tropical coastal lagoons: Implications for management

“…Since waterbird abundance represents a recognized metric for habitat use (Baschuk et al, 2012;Lunardi et al, 2012;Paracuellos and Tellería, 2004), we assessed the effects of hydrochemical, structural and anthropogenic factors on the abundance of different guilds. Specifically, we tested the expectation that different guilds should show specific responses to variations in water depth, vegetation height, lagoon size, water salinity, water pH, grazing pressure, and distance from human settlements (Cumming et al, 2012;Guadagnin and Maltchik, 2007;Pérez-Crespo et al, 2013;Sebastián-González and Green, 2014). Knowledge regarding the use of habitats by waterbirds is particularly poor in tropical and subtropical coastal systems, which harbor complex arrays of habitats and unique bird communities (Gianuca et al, 2014;Lunardi et al, 2012;Tavares and Siciliano, 2014a).…”