WbS and IWSG Joint Conference Wilhelmshaven 2013 ABSTRACTS - TALKS |56 37th annual meeting of the Waterbird Society Wilhelmshaven 2013 Beyond aggregate life history trajectories: insight from a 35-year study on Kittiwakes Emmanuelle Cam1 & Jean-Yves Monnat2 1 Laboratoire Evolution et Diversité Biologique, Université Paul Sabatier, Toulouse, France; [email protected] 2 Penn Ar Run Izella, Goulien, France The growing richness of data collected in ongoing long-term longitudinal studies from marked wild vertebrates in conjunction with theoretical and technical progress in statistical tools have led to a progressive upgrade in the biological questions that can be addressed. Many early efforts have focused on evaluation of the relationship between biological or environmental factors (sex, habitat features) and the diversity of life history trajectories and lifetime production in populations, or the description of age- specific life history traits, mostly within the theoretical framework of trade-offs between traits. Subsequently, the significance of such studies has often been devalued in the literature because experimentation is assumed to allow stronger inferences about the processes underlying life history evolution. Experimentation is impossible in retrospective studies or undesirable in ongoing studies that have to maintain consistency in observations. However, the lack of insight on the representativeness of conditions created in experimental studies and in short-term studies in general has led to awareness of the limitations of such studies. Contemporary studies are benefiting from the call from other areas of research for tests of theories in quantitative genetics, population ecology and population dynamics using long-term non-experimental data. Here we adopt a ‘historical’ perspective on a 35-year study of Kittiwakes Rissa tridactyla conducted in Brittany (France) and analyze the changes in the questions about the evolution of life histories driven by new observations and changes in analytical tools. In particular we detail the input from other disciplines also addressing longitudinal data, our progression towards model-based inferences about individual fitness, and the use of conceptual constructs developed in other areas to account for the diversity of individual ‘responses’ (e.g., survival in life history studies). Analyzing long-term longitudinal data with a high degree of stratification according to individual and environmental features raises specific difficulties in terms of statistical inference. We address the new challenges we have to take up to address seemingly old questions raised in early studies of life histories of wild vertebrates. Wednesday, 25th September 2013 – PLENARY |57 37th annual meeting of the Waterbird Society Wilhelmshaven 2013 The Study of Career Decisions: Oystercatchers as Social Prisoners Bruno J. Ens1,* & Martijn van de Pol2,3 1 Sovon Dutch Centre for Field Ornithology, Nijmegen, The Netherlands 2 Netherlands Institute of Ecology, Wageningen, The Netherlands 3 Australian National University, Canberra, Australia * [email protected] Because resources are limited, animal populations cannot grow forever and the ensuing struggle for existence subjects them to the relentless force of natural selection (Darwin, 1859). Thus, competition among animals for limited resources is a defining property of life. In the case of our study species, the Oystercatcher, access to these limiting resources depends on their social position as a member of a social system or animal society. There are three descriptions of aspects of animal societies in terms of competition, each accompanied by their own body of theory: 1. Distribution theories describe the access of individual animals to limiting resources in space. 2. Life history theory describes the access of individual animals to limiting resources in the course of their life, and how these resources are allocated to survival and reproduction. 3. Mating systems theory describes the access of individual animals to partners as a resource limiting reproduction. According to Wilson (1998), the ultimate goal of science is to unite different fields of knowledge and his term for this enterprise is consilience. Our modest contribution to consilience is the attempt to combine adaptive distribution theory to life history theory and mating systems theory to better understand the social organization of our study species. As Wilson (1975) formulated it nearly three decades ago: The ultimate goal is a stoichiometry of social evolution. When perfected, the stoichiometry will consist of an interlocking set of models that permit the quantitative prediction of the qualities of social organization - group size, age composition, and mode of organization, including communication, division of labor, and time budgets - from a knowledge of the prime movers of social evolution". We will describe the progress we have made towards this goal in our thirty-year study of an Oystercatcher population breeding on the island of Schiermonnikoog." Wednesday, 25th September 2013 – ORAL SESSION LIFE HISTORY |58 37th annual meeting of the Waterbird Society Wilhelmshaven 2013 Black Tern pairbond and breeding site fidelity in The Netherlands Jan van der Winden Bureau Waardenburg, Consultants for Ecology and Environment, Culemborg, The Netherlands; [email protected] Within the family Sternidae, the social behaviour of the genus Chlidonias is relatively poorly studied compared to the genus Sterna. Although widespread over Europe, the breeding habitat of Chlidonias terns, in less accessible marshlands, makes studies difficult. Species of the genus Sterna but also of the genus Gelochelidon and Hydroprogne are monogamous with a high year-to-year pair bond fidelity, e.g. with an estimated 75% inter season pair bond fidelity in Common Tern Sterna hirundo. Several Sterna species also show a relatively high site fidelity. In order to get more information on pair bond and site fidelity in Chlidonias terns, a colour ring study had been started in 2002 with 30 individually ringed birds until 2012 in a colony of 20 to 25 pairs. The colony is situated close to a touristic area and birds are used to human presence and therefore it is possible to check colour rings from a close distance. Birds are regarded as divorced if both are present in the next year but without a pair bond. The data suggest that Black Terns have no year-to-year pair bond and also divorces within a season after nest losses are usual. 47% of the Black Terns returned to the same colony at least one year but movements to another colony are also recorded yearly. Thus, in terms of social behaviour Black Terns are quite different from Sterna terns. This might be related to the low habitat and nest site predictability. Locations of marsh with suitable nest substrates are on average less predictable than Sterna habitat on islands. So time to wait and search for the partner of the previous year might be less rewarding. In this respect it will be interesting to study the selection processes in partner choice in this species compared to others in the Sternidae family. Wednesday, 25th September 2013 – ORAL SESSION LIFE HISTORY |59 37th annual meeting of the Waterbird Society Wilhelmshaven 2013 The effect of body condition on short- and long-term fitness: why fat plovers may be better plovers Daniel Catlin*, James D. Fraser, Kelsi Hunt, Meryl Friedrich & Sarah M. Karpanty Virginia Tech, Blacksburg, Virginia, USA * [email protected] Individual condition of precocial chicks prior to fledging can have significant impacts on chick survival and thus population growth. Less is known, however, about the potential sub-lethal and chronic effects of poor body condition on lifetime fitness. We studied the relationship of chick fledging condition with short- and long-term survival and with measures of reproductive output in Piping Plovers nesting on the Missouri River from 2005-2012. In addition, we examined ecological and management variables to determine which of these were determining the growth and condition of chicks at fledging. We found that the condition of fledglings was not only associated with hatch- year survival, but also was positively correlated with survival in subsequent years, such that birds in better condition at fledging had higher lifetime survival than those in worse condition. Moreover, chicks that fledged in better condition than others, tended to be in better condition as adults. Chick growth and condition at fledging were related to measures of parental condition, availability of foraging habitat, and to environmental variables. In particular, the density of individuals per unit of foraging substrate was negatively correlated with the rate of chick growth as well as the condition of chicks at fledging. On the Missouri River, water management policies tend to increase densities during chick rearing, potentially affecting the long-term fitness of the plovers. Our results indicate that there are significant carryover effects of chick condition that could be capitalized on by managers to improve overall population fitness. Wednesday, 25th September 2013 – ORAL SESSION LIFE HISTORY |60 37th annual meeting of the Waterbird Society Wilhelmshaven 2013 Fitness prospects: effects of gender, recruitment age and senescence on reproductive value in a long-lived seabird He Zhang1,*, Maren Rebke2, Sandra Bouwhuis1 & Peter H. Becker1 1 Institute of Avian Research ‘Vogelwarte Helgoland’, Wilhelmshaven, Germany 2 Max Planck Institute for Demographic