Birds have developed many strategies, behaviour and morphology to maximize the diversity of ecological niches available in the wetlands for their key life moments. Just as an example, there is more to think about the many ways and how they use their beak, which gives them greater success in obtaining food, such as fish of various sizes (herons, loons, kingfishers), insects (gulls, stilts, curlew), different parts of plants (with the variety of morphology in waterfowl), or even with respect to the place where (full spectrum of forms within the group of waders) they are fed.
Therefore, birds are one of the species that have the value of telling us by their absence, presence and changes in numbers, changes in the ecological status of a given environment.
In this context, the aquatic birds or depending on the aquatic ecosystems, especially those with more stringent and water bodies associated with good quality ecological requirements, can be a good indicator for estimating the state of conservation of wetlands. For example, the crested coot (Fulica cristata) and the red-crested porchard (Netta rufina) are a priori indicators of the existence of macrophytes in the wetland (in particular those of the type Chara and Myriophyllum), through ecological relationships and trophic states between breeding waterfowl, their offspring, the physical-chemical environment and biological groups that represent their livelihood during reproduction.
But it is not only during reproduction time when the requirements of each species (requirements, on the other hand, will vary throughout the year even for the same species) should be analyzed. Some knowledge of the use of these ecological niches available and structural or biological elements of aquatic ecosystems associated with them (directly related indicators DMA) is essential to design and implement the most appropriate conservation actions in this faunal group.
A revision of the role of indicators of some species can be found here:
http://www.seo.org/wp-content/uploads/tmp/docs/Manual_DMA_SEO_Def_Baja.pdf
Other data, in summary:
- Kingfisher: During reproduction, they are a clear indicator of the presence of natural slopes and low fluctuation levels;
- Terns: During reproduction, they are indicative of the presence of aquatic macrophytes to reach the surface and achieve good coverage, being where they build their nests;
- Grebes: given the fact that they build their nest on aquatic vegetation, they are indicative of little change in water level;
- Harrier: During reproduction, they indicate the abundance of amphibians, rodents, chickens of water birds like the coot or purple gallinule, with which they feed their own offspring;
- Great Bittern: throughout the year, they are indicative of abundance of small fish, dense and lush vegetation, the presence of shallow waters and little variation in water levels;
In addition, waterfowl show fidelity to breeding areas at river basins or biogeographic regions, so that if the ecological status of a wetland is altered, the most demanding waterfowl in reproduction respond looking for a new location that meets the right conditions. It is this response that gives us the key to using birds as indicators. Basically, “if they like it, they will stay, and if not, they will leave.”
One objectiveof thisproject is to establisha direct relationship between the indicators of the Water FrameworkDirectiveandthe potential of theelements analyzedforthe studied species. So, given that many of the measuresdealing withwetlands(and thereforewaterfowl) are of the responsibility ofriver basin plans, it is possible to plan specific actionsandmeasures to improvethe indicators connected towaterfowl, by integrating them in the management plans of wetlandsoftheNatura2000 network and water management plans.
It is,after all, with the helpof birds andtheir role asbioindicators that we develop anddesignmore efficientmanagement plansforwetlands ofthe Natura 2000 network, thereby ensuring the improvement andconservation of waterfowl populations.