River functionality influences the distribution of the dipper Cinclus cinclus (Linnaeus, 1758)

Area of Science:

• Ecology
• Conservation Biology
• Environmental Science

Background:

• The dipper (Cinclus cinclus) is a bioindicator species linked to riparian ecosystems and aquatic macroinvertebrates.
• Limited research exists on dipper distribution and ecology in Central Italy, hindering conservation efforts.
• Previous studies highlight dippers as potential bioindicators of water quality.

Purpose of the Study:

• To assess dipper occurrence in relation to water quality using diatom and macroinvertebrate biotic indices.
• To evaluate the overall river ecosystem state using the River Functionality Index and land-use analysis.
• To understand factors influencing dipper presence in Central Italian rivers.

Main Methods:

• Biotic indices based on diatom and macroinvertebrate communities were used to assess water quality.
• The River Functionality Index was applied to evaluate the riparian ecosystem's overall state.
• Land-use analysis was conducted in buffer areas around dipper presence sites.

Main Results:

• Water quality alone did not fully explain dipper occurrence; the species was absent from some sites with good water quality.
• Diatom and macroinvertebrate diversity were insufficient to predict dipper presence.
• Dipper occurrence significantly correlated with the River Functionality Index, indicating a preference for well-preserved, functional ecosystems.

Conclusions:

• River ecosystem health and functionality are key drivers of dipper occurrence in Central Italy.
• The dipper could serve as an umbrella species for riparian ecosystem conservation.
• Urgent research on dipper auto-ecology and conservation threats is needed for Central Italy.