caa a22 4500 445894709 CHVBK 20180317145628.0 cr unu---uuuuu 170323e20110401xx s 000 0 eng 10.1007/s10750-010-0596-x doi (NATIONALLICENCE)springer-10.1007/s10750-010-0596-x Behavioural and population responses to changing availability of Artemia prey by moulting black-necked grebes, Podiceps nigricollis [Elektronische Daten] [Nico Varo, Andy Green, Marta Sánchez, Cristina Ramo, Jesús Gómez, Juan Amat] We examined how availability of brine shrimps, Artemia parthenogenetica, influenced temporal aspects of foraging behaviour and population dynamics of moulting black-necked grebes, Podiceps nigricollis, from late August to early December in four salt ponds in the Odiel marshes, southern Spain, in 2008 and 2009. The moulting grebe population was higher in 2009, coinciding with an increase in shrimp biomass, with a peak of 2,500 birds in October. Grebes increased their time spent foraging as the season progressed, coinciding with decreases in shrimp biomass and water temperature. Foraging activity was lower in 2009, when shrimp biomass was greater. Diving was the most frequent feeding method, especially as the season progressed. Brine shrimps at the bottom of the water column were larger than those near the surface. Differences between years in grebe body mass suggest that changing shrimp availability and water temperature had an influence on body condition. The grebe population consumed an estimated 0.2-2.0% of the standing crop of Artemia per day, with this fraction increasing as the season progresses, thus contributing to the decline in the Artemia population. Our results suggest that moulting grebes are probably only able to adjust foraging effort within certain limits, especially at the end of moulting period when thermal stress is greatest and food supply is lowest. They may leave the study area when they can no longer meet their energy requirements. Springer Science+Business Media B.V., 2011 Brine shrimps nationallicence Foraging behaviour nationallicence Grebes nationallicence Mediterranean wetlands nationallicence Waterbirds nationallicence Varo Nico Department of Wetland Ecology, Estación Biológica de Doñana, C. S. I. C, Calle Américo Vespucio s/n, 41092, Sevilla, Spain aut Green Andy Department of Wetland Ecology, Estación Biológica de Doñana, C. S. I. C, Calle Américo Vespucio s/n, 41092, Sevilla, Spain aut Sánchez Marta Department of Wetland Ecology, Estación Biológica de Doñana, C. S. I. C, Calle Américo Vespucio s/n, 41092, Sevilla, Spain aut Ramo Cristina Department of Wetland Ecology, Estación Biológica de Doñana, C. S. I. C, Calle Américo Vespucio s/n, 41092, Sevilla, Spain aut Gómez Jesús Department of Wetland Ecology, Estación Biológica de Doñana, C. S. I. C, Calle Américo Vespucio s/n, 41092, Sevilla, Spain aut Amat Juan Department of Wetland Ecology, Estación Biológica de Doñana, C. S. I. C, Calle Américo Vespucio s/n, 41092, Sevilla, Spain aut Hydrobiologia Springer Netherlands 664/1(2011-04-01), 163-171 0018-8158 664:1<163 2011 664 10750 https://doi.org/10.1007/s10750-010-0596-x text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10750-010-0596-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Varo Nico Department of Wetland Ecology, Estación Biológica de Doñana, C. S. I. C, Calle Américo Vespucio s/n, 41092, Sevilla, Spain aut NATIONALLICENCE 700 1- Green Andy Department of Wetland Ecology, Estación Biológica de Doñana, C. S. I. C, Calle Américo Vespucio s/n, 41092, Sevilla, Spain aut NATIONALLICENCE 700 1- Sánchez Marta Department of Wetland Ecology, Estación Biológica de Doñana, C. S. I. C, Calle Américo Vespucio s/n, 41092, Sevilla, Spain aut NATIONALLICENCE 700 1- Ramo Cristina Department of Wetland Ecology, Estación Biológica de Doñana, C. S. I. C, Calle Américo Vespucio s/n, 41092, Sevilla, Spain aut NATIONALLICENCE 700 1- Gómez Jesús Department of Wetland Ecology, Estación Biológica de Doñana, C. S. I. C, Calle Américo Vespucio s/n, 41092, Sevilla, Spain aut NATIONALLICENCE 700 1- Amat Juan Department of Wetland Ecology, Estación Biológica de Doñana, C. S. I. C, Calle Américo Vespucio s/n, 41092, Sevilla, Spain aut NATIONALLICENCE 773 0- Hydrobiologia Springer Netherlands 664/1(2011-04-01), 163-171 0018-8158 664:1<163 2011 664 10750 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer