Over the past two centuries, anadromous alewife populations have drastically declined due to damming, inadequate fish passage, overfishing in the ocean and freshwater, climate change, and reduction in habitat quality. Alewife populations are currently assessed by counting adult fish as they migrate upstream, but little is known about resulting juvenile production within lakes. Lack of knowledge of freshwater life history characteristics of juvenile alewife limits our understanding of overall productivity. For this thesis, I fill existing information gaps by (1) characterizing the timing of adult alewife migrations and subsequent spawning (Chapter 2), and (2) assessing juvenile alewife density, size, growth, and mortality within lakes, and abiotic factors influencing these estimates across lakes (Chapter 3). Twenty lakes across coastal Massachusetts were sampled for juvenile alewife and water quality in summer 2014. Each lake was sampled three times: Round 1 (29 May to 15 June), Round 2 (26 June to 16 July), and Round 3 (27 July to 15 August). Analyses of instream adult counts and otolith-based estimates of spawning date from captured juveniles showed a distinct delay (7-28 d) between the beginning of the adult migration run and spawning, and spawning continued 13-48 days after adults stopped migrating. These findings further corroborate recent discoveries that suggest alewife exhibit asynchronous spawning and has large implications for freshwater foodwebs. Lakes, overall, did not produce the same sized fish and there appears to be substantial variations of length-at-age with some lakes exhibiting large differences. No change in length-at-age occurred in August, thus differences were achieved earlier in the growing season. Additionally, all 20 lakes exhibited variable growth, density, and mortality rates that yielded generally weak relationships with abiotic and biotic factors. Juvenile alewife density was positively related to juvenile density in the previous sampling Round, suggesting that a single sampling date may be sufficient to estimate relative lake density across the landscape. Factors affecting growth were not consistent; overall growth was positively correlated with DOC, while the last 20 days of growth was negatively correlated with secchi depth. While different, these responses are likely the result of the same mechanisms, both intrinsically linked with zooplankton abundance, prey availability, and feeding behavior within lakes. No significant correlate was found for mortality. In the future, the data in this thesis can be incorporated into models to improve stock assessments and support timely adaptive management strategies.

This thesis presents an osteoarchaeological analysis of juvenile mortality profiles questioning the speculations made by some archaeologists that the under-representation of infants from Anglo-Saxon and medieval burial populations could be due to the practice of infanticide in England during these periods. Morphological and metrical age estimation and sex assessment methods are used to determine the age-at-death and sex of 1275 children from fifty-three Anglo-Saxon and medieval sites located in southern England. The age and sex distribution of the Anglo-Saxon and medieval children under six-years-old are then compared with age-specific United Nations demographic statistics see to whether or not a normative mortality profile is presented by the archaeological populations. This study identified an abnormal age-at-death distribution for the early Anglo-Saxon perinatal individuals. Excess female mortality was observed for the perinatal individuals from all three periods; early Anglo-Saxon, late Anglo-Saxon and medieval, and for the neonatal and infant individuals from the early Anglo-Saxon and medieval periods. The results of this osteoarchaeological analysis are discussed in conjunction with a review of the Anglo-Saxon and medieval documentary evidence which examines the possible social and economic motives for infanticide. Whilst this analysis of the historical sources revealed laws and penitentiary warnings against the neglect and deliberate murder of infants, the late Anglo-Saxon and medieval documents provided little evidence to suggest the social devaluation of women that would support a hypothesis of preferential female infanticide. There are few surviving early Anglo-Saxon documents however, so the significance of the abnormal mortality profiles from this period is considered.

This thesis presents an osteoarchaeological analysis of juvenile mortality profiles questioning the speculations made by some archaeologists that the under-representation of infants from Anglo-Saxon and medieval burial populations could be due to the practice of infanticide in England during these periods. Morphological and metrical age estimation and sex assessment methods are used to determine the age-at-death and sex of 1275 children from fifty-three Anglo-Saxon and medieval sites located in southern England. The age and sex distribution of the Anglo-Saxon and medieval children under six-years-old are then compared with age-specific United Nations demographic statistics see to whether or not a normative mortality profile is presented by the archaeological populations. This study identified an abnormal age-at-death distribution for the early Anglo-Saxon perinatal individuals. Excess female mortality was observed for the perinatal individuals from all three periods; early Anglo-Saxon, late Anglo-Saxon and medieval, and for the neonatal and infant individuals from the early Anglo-Saxon and medieval periods. The results of this osteoarchaeological analysis are discussed in conjunction with a review of the Anglo-Saxon and medieval documentary evidence which examines the possible social and economic motives for infanticide. Whilst this analysis of the historical sources revealed laws and penitentiary warnings against the neglect and deliberate murder of infants, the late Anglo-Saxon and medieval documents provided little evidence to suggest the social devaluation of women that would support a hypothesis of preferential female infanticide. There are few surviving early Anglo-Saxon documents however, so the significance of the abnormal mortality profiles from this period is considered. / Arts and Humanities Research Council