This research delves into the many functions played by bird communities in southern Iran’s wetland coastal wetlands and mangroves through sampling 88 species at 29 sites specifically selected to be studied. It does not target the question of which particular species inhabit each site, but the range of physical and behavioral characteristics—such as size, diet, and habitat use—that the birds contribute to the ecosystems. Plotting the distribution of these characteristics between the birds at each site, the research uncovers the way that sets of species interact to deliver functions such as nutrient cycling, seed dispersal, and shore stability. A trait‑based approach presents a richer vision of biodiversity, revealing not only the number of birds that inhabit an area, but how, collectively, such crucial habitats operate efficiently.

The results reveal a strong correlation between the number of species at one site and the range of ecological functions that they support: sites that contain more species supported a wider “toolkit” of functions, which indicates higher resilience to change. It indicates particular clusters of birds—functional guilds—which live the same way, highlighting the value of keeping common and uncommon birds around to ensure healthy ecosystems. It is ultimately providing conservation planners with practical advice, however, to protect the complete range of bird functions, not just protecting the birds themselves, if we are to ensure that these wetlands and mangroves are healthy and successful.