Over the last century anadromous alewife (Alosa psuedoharengus) and blueback herring (Alosa aestivalis), collectively called river herring, suffered drastic declines throughout their range from Newfoundland (Canada) to North Carolina (USA). A 2011 petition to include river herring in the Endangered Species Act (ESA) was rejected, partly due to inadequate information towards identifying coast-wide population status. Additionally, knowledge gaps were identified with basic ecology of the river herring life cycle in freshwater, including species reproductive strategies. In Chapter 2, I investigated how body size, spawning arrival time, and sex influence river herring reproductive success. I collaborated with the Massachusetts Division of Marine Fisheries to introduce adult river herring (421, 266, and 410 individuals in 2013, 2014, and 2015, respectively) into Pentucket Pond (Massachusetts, USA), which historically had river herring but is currently inaccessible to upstream migrants. Using fin clips from stocked adult fish and juveniles collected in the lake each summer, I genotyped individuals and constructed pedigrees with 15 microsatellites. River herring had small (mean =1.1) families and spawned multiple times with multiple mates from May to June. Females were more successful than males. Earlier arrival and larger body size were independent indicators of reproductive success. These results provide critical river herring life history information for the freshwater component of population models that will inform management of this at-risk species. Presently, most river herring populations are monitored using data from citizen counts of spawning adults entering freshwater. Involving citizen watershed groups in data collection and may provide ancillary benefits beyond collection of population-level count data. In Chapter 3, I used pre-and post-surveys to assess how involvement in one citizen monitoring program influenced participants’ environmental knowledge, attitudes, and behaviors. Participants began the program with high scores for broader scientific and pro-environmental attitudes and pro-environmental behaviors. After the program, participants reported increased connection to nature, citizen science involvement, river herring knowledge, and engagement in outdoor recreation. For participants, engagement with nature was the most important program benefit. These results provide an additional case study to the citizen science literature and demonstrate that citizen science programs can help participants connect with the environment.

The seasonal and diel feeding habits of the goosander, Mergus merganser, the red-breasted merganser, M. serrator, gulls (Larus canus, L. argentatus and L. fuscusj and terns, Sterna hirundo/paradisaea were studied at 64V05'N. Birds' activity patterns were influenced by the nocturnal spawning of the river lamprey (Lampetra fluviatilis). Food selection and food consumption by hand-raised mergansers together with aquarium studies of the diel activity patterns of their most important prey supplemented the field data. River lamprey dominated the diet of the goosander by weight and the sculpin Cottus gobio by number. The fish consumption of the goosanders was found to be about 12% of the available river lamprey biomass and about 17% of the sculpin biomass during the breeding season. In experimental situations the river lamprey was a low- pritority species compared with salmon , Salmo salar, brown trout, 53. trutta, and minnow, Phoxinus phoxinus, when presented to satiated birds of both Mergus species. When hungry, however, the birds caught the available prey irrespective of species, but they selected larger prey when two size classes were present. Experimental results were compared with field data on availability, consumption and the escape behaviour of the various fish species. The rivers emptying in the Bothnian Bay are regarded as important feeding areas for birds breeding along the coast. In early spring they get access to abundant and reliable food resources, e.g the river lamprey. Later on the three-spined stickleback, Gasterosteus aculeatus, supply both Mergus species with food in the river and also along the coast. From the middle of June potential food supply available to birds decreases in the rivers and becomes more abundant in the coastal area. / <p>S. 1-41: sammanfattning, s. 43-227: 7 uppsatser</p> / digitalisering@umu