Habitat selection and reproductive success of coot Fulica atra on ponds under different fish size and density conditions

Abstract

Fish may influence habitat selection and reproductive success in waterfowl. We investigated the effects of common carp Cyprinus carpio on breeding coots Fulica atra along a gradient of fish size structure and density, created by separate stocking of age cohorts in ponds in eastern Poland. Coot breeding densities were higher on ponds with low biomass of small-sized, young-of-the-year fish than on ponds with medium-or large-sized fish, stocked at high biomass densities; they also increased with increasing submerged vegetation biomass (an effect correlated with water transparency) and emergent vegetation cover. Densities of nektonic and epibenthic macroinvertebrates and of amphibian larvae were also negatively influenced by fish size/density gradient, while densities of emerging insects were not affected. However, coot breeding success per pair was similar among pond types, while positively related to submerged vegetation, indicating that either plant food abundance was more important than the overall trophic impact of fish or fledgling production was additionally limited by factors other than food. Carp may adversely affect pond habitats of waterfowl both via trophic interactions and through abiotic disturbance of ecosystem processes. In coots, however, the effects can be mitigated by maintenance of abundant emergent vegetation and of submerged macrophytes resistant to fish.

Notes on the nesting and foraging behaviours of the Common Coot Fulica atra in the wetlands of Viluppuram District, Tamil Nadu, India

“…In the present study area, diverse animal/ plant species, such as snails, insects, five algal species, and eleven macrophytes including submerged, floating and terrestrial plants played an important role as a food source of Common Coots. Hence, the present study corroborates the findings of Martin et al (1997), Draulans & Vanherck (1987), Howes & Perrow (1994), and Nieoczym & Kloskowski (2018).…”

“…In southern Algeria, 63.2% of nests of Common Coot were associated with Phragmites australis probably to reduce predation risk from the air (Samraoui & Samraoui 2007). Emergent vegetation is important for habitat selection by Coots, presumably because it provides nesting habitats and protection against aerial predators (Nieoczym & Kloskowski 2018). In the present study, 89.75% of nests were built in emergent vegetation I. carnea probably to avoid aerial predators as stated by Samraoui & Samraoui (2007) and Nieoczym & Kloskowski (2018).…”

“…Emergent vegetation is important for habitat selection by Coots, presumably because it provides nesting habitats and protection against aerial predators (Nieoczym & Kloskowski 2018). In the present study, 89.75% of nests were built in emergent vegetation I. carnea probably to avoid aerial predators as stated by Samraoui & Samraoui (2007) and Nieoczym & Kloskowski (2018). Most of the nests of Common Coot were associated with T. angustifolia in Algerian Sahara (El-Yamine et al 2018).…”

“…Sago pondweed Stuckenia pectinata in France and Germany (Allouche & Tamisier 1984;Hilt 2006) and Watermilfoil Myriophyllum verticillatum and horn-wort Ceratophyllum demersum in China are their main sources of food (Wang et al 1990;Zhang & Ma 2011). Submerged vegetation is an important food source for Common Coot and it is positively related to its breeding success (Nieoczym & Kloskowski 2018). The Common Coots exhibit considerable plasticity in their foraging behaviours by foraging on a wide range of plants and animal materials,…”