Browsing by Subject "Reproductive success"

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    The causes and consequences of individual variation in survival and fecundity of Great Lakes piping plovers (Charadrius melodus)
    (2015-03) Saunders, Sarah Prairie
    The piping plover (Charadrius melodus) is a small shorebird endemic to North America and restricted to three breeding populations: Atlantic Coast, Great Plains, and Great Lakes. Listed as federally endangered in 1986, the Great Lakes population has numbered from 17 to 71 known breeding pairs. Despite recovery efforts, the population is far from the federal recovery goal of 150 breeding pairs. The purpose of my dissertation research is to understand the causes and consequences of individual variation in survival and fecundity during key breeding stages through four distinct methods of investigation: life-history theory, quantitative genetic analysis, population demography, and behavioral assessment. Effective conservation of small wildlife populations requires the intersection of many scientific disciplines and I seek to achieve this unification through the four chapters of my dissertation. First, I investigate how age and parental experience with breeding, a mate, and a nesting location influence reproductive success (Chapter 1). In chapter 2, I investigate the heritabilities of three fitness-related traits (chick body mass, natal dispersal distance, and female timing of breeding) to determine which are strongly environmentally-determined and thus susceptible to impacts of global climate change. In chapter 3, I tease apart the relative influences of various developmental and environmental factors at pre-fledging, post-fledging, and adult stages to more precisely inform population recovery actions. In my final chapter, I test the hypothesis that captive-reared chicks have lower survival rates than those reared in the wild because of a lack of threat recognition. The insights gained from my research not only pertain to this small shorebird breeding in the Great Lakes, but also provide a more comprehensive framework for analyzing data on marked individuals with the goal of shaping conservation actions for an entire population. Further, the new analytical methods applied to ecologically complex data will be important to any study that uses long-term marking. Avian populations are predicted to become more threatened in the future, so it is increasingly critical to understand factors driving vital rates and to develop approaches to alleviate threats to population persistence.
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    Paternity and father-offspring relationships in wild chimpanzees, Pan troglodytes schweinfurthii.
    (2010-03) Wroblewski, Emily Elizabeth
    Hamilton's seminal theory of kin selection asserts that because relatives share a certain proportion of genes, individuals can increase their inclusive fitness by helping and/or not harming kin, as long as the benefits to kin outweigh the costs to the individual. We would expect animals to attain maximal inclusive fitness by discriminating both the available maternal and paternal kin from non-kin in their social groups. The primate order is a useful taxon in which to study kin selection and kin discrimination because most primates live in permanent social groups with both kin and non-kin between which to discriminate, and their complex social interactions provide many opportunities to both hurt and aid others. However, the prevailing view has been that the discrimination of paternal kin does not occur in most species. Despite emerging studies that suggest otherwise, study of paternal kin discrimination thus far has been limited in primates. Furthermore, study has been restricted to matrilineal species with male-biased dispersal. Paternal kinship could also be important in a patrilineal species such as chimpanzees as males will remain with fathers and other paternal kin for life, as will females until they disperse. Thus, this study aimed to further our understanding of importance of paternal kinship in social behavior by examining the most direct paternal relationship, that of fathers and offspring, in the chimpanzees of Gombe National Park, Tanzania. Identifying fathers and offspring and characterizing their relationship is a necessary first step on the way to testing for kin discrimination amongst non-descendent paternal kin. Thus, in Chapter 1, I first determined paternal relationships and explored patterns of male reproductive success relative to dominance rank and the priority of access model, as well as fathers' mating strategy and age. Then in Chapter 2, I examined whether fathers showed parental investment in their juvenile and adolescent sons. Finally, in Chapter 3, I investigated whether there was inbreeding avoidance between fathers and daughters.