Diversity of waterbirds wintering in Douz wetlands (south Tunisia): factors affecting wetland occupancy and species richness

Abstract

Understanding the environmental factors shaping wetland attractiveness for waterbirds is an important question in wetland ecology and for conservation purposes. However, detailed data from numerous North African wetlands, notably those situated in inland areas, are still lacking. Thus, the aim of this study was to identify the factors influencing wetland use by waterbirds wintering in one of such poorly known habitat systems, namely the Saharan wetland complex of Douz, in south‐western Tunisia. Thirty‐four waterbird species (20 wading birds and 14 waterfowl species) were found to winter in this area. Using discriminant function analyses, we found that wetland size was the unique variable discriminating between occupied and unoccupied sites for total waterbirds and wading birds, while waterfowl distribution was related to both wetland size and water depth. Wetland size also provided the strongest predictor of species richness of wading birds, waterfowl and total waterbirds. Overall, our findings highlight the importance of wetland size as a key factor determining the attractiveness of wetlands for waterbirds wintering in the Saharan wetland complex of Douz. The possible explanations of this wetland size effect are discussed.

Diversity and Abundance of Breeding Birds, Habitat, and Nesting Substrate Selection in Urban Areas: A Relevant Case from the Southern Slope of the Mediterranean

“…In the Northern slope of the Mediterranean, our results are very close to those cited in Kavala (Greece) and in Rovaniemi (Finland) with 26 and 15 breeding species, respectively. However, the recorded breeding birds are inferior when compared to other Moroccan ecosystems counting farmlands that host nearly 60 breeding birds [36], forests with 70 breeding species [22,24,47], and wetlands with nearly 100 breeding species [14]. Te increased urbanization rate is suggested to be behind this lower avian diversity in Fez city.…”

“…Nests of birds of prey Falco tinnunculus and Accipiter nisus were built separately in urban forests far from the breeding passerines. Te segregation of breeding habitats between predators and preys is currently cited among avian species [56,57] as in the case of olive orchards surrounding Fez city [18] in which the breeding Doves (Streptopelia decaocto and Streptopelia turtur) nested far from the predatory Maghreb magpie (Pica mauritanica) and the case of Oued Bouhellou watershed in which the community of breeding passerines selected nesting sites far from the birds of prey counting Falco tinnunculus, Falco naumanni, Buteo rufnus, Circus aeruginosus, Elanus caeruleus, Lanius excubitor, and Lanius senator [47]. In the same way, our study revealed a clear habitat partitioning between Streptopelia decaocto that nested in urban farmlands and its competitor Spilopelia senegalensis concentrated in green gardens.…”

“…Similarly, the selection of nesting supports (eight species of trees and wall cavities) used by breeding bird species (105 nests of 13 species) was evaluated by detrended correspondence analysis (DCA) in the same way as habitat use. Tis multivariate method is widely used to evaluate the ecological requirements counting habitat use and nesting supports for bird species [19,47]. All analyses were performed using SPSS 18.…”

Finding Out Suitable Index for Wetland Mapping in Barind Plain of India and Predicting Dynamics of Its Area and Depth

“…Wetland depth is very essential for sustaining different species (Lantz et al, 2011;Hamza and Selmi, 2018). Depth is a hydro-ecological aspect whose variation is linked to the species richness, diversity, comfortability, particularly to the fish species (Hamza and Selmi, 2018;Ouma, 2020). Wetland trend analysis (depth and area) is very essential for sustainable management planning.…”