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Item Harvest, nasal-markers, and lesser scaup vital rates(Montana State University - Bozeman, College of Letters & Science, 2017) Deane, Cody Earle; Chairperson, Graduate Committee: Jay J. RotellaSince the mid-1980s, lesser scaup (Aythya affinis) population abundance has been approximately 20% below the North American Waterfowl Management Plan goal of 6.3 million lesser adult lesser scaup. Sustained harvest opportunity of this species is an important management goal in North America. We examined the relationship between harvest mortality and survival rates for a breeding population in southwest Montana from 2005 to 2016 when Adaptive Harvest Management was implemented for lesser scaup. We combined resighting, recapture, and hunter recovery to estimate survival and harvest rates using multistate capture-mark-recapture models in Program MARK. Nasal-marker loss rates were substantial and accounted for by allowing resight detection probability to decay with nasal-marker age. Adult female survival rates tended to be positively related to an interaction between annual Pacific flyway lesser scaup harvest and this value divided by the Pacific flyway daily bag limit, which we used as an index for population density (beta INTERACTION = 0.168, SE = 0.091). Estimated annual survival rates for adult metal-banded females averaged 0.66 (SE = 0.03) and 0.49 (SE = 0.02) for adult nasal-marked females, while first-winter survival rates averaged 0.39 (SE = 0.03) for metal-banded juveniles and 0.23 (SE = 0.02) for nasal-marked juveniles. However, this decrease in survival rates is not attributable to differing harvest rates between nasal-marked and metal-banded females (beta NASAL-MARKED, HARVEST RATE = 0.101, SE = 0.166). Body condition of nasal-marked females did not differ from unmarked females as their residual body mass was 1.6 g (SE = 10.4 g) less during the pre-breeding season and 3.5 g (SE = 6.5 g) less during the brood-rearing period. Nasal-marked females were found to have delayed initiating nests by 3.6 days (SE = 1.9 days) and laid 0.5 fewer eggs (SE = 0.3 eggs) relative to unmarked females while they hatched ducklings weighing 0.2 g (SE 0.2 g) more than unmarked females. Nasal-marked females were harvested 154.9 km (SE = 112.5 km) further from the study site than unmarked females, suggesting nasal-markers don't impede migration ability. Cumulatively, our results for nasal-marker impacts on vital rates suggest substantial individual heterogeneity among individuals exists in this population.Item Factors influencing the density and distribution of breeding waterfowl in North-Central Montana(Montana State University - Bozeman, College of Letters & Science, 2011) Fields, Sean Patrick; Chairperson, Graduate Committee: Jay J. RotellaContinental waterfowl population declines in the early 1980s led to the development and implementation of the North American Waterfowl Management Plan. The plan identified wetland and grassland losses in the Prairie Pothole Region (PPR) of Canada and the United States as the major causes of low continental duck populations. North-central Montana is the only remaining PPR area in the United States without a ground-based annual survey to monitor breeding duck populations and quantify breeding duck habitat. The purpose of this study was to establish an annual breeding duck survey in north-central Montana to 1) develop species-specific breeding pair predictive models, and 2) apply the models to estimate the density and distribution of breeding ducks and identify priority areas for conservation actions. 1969 indicated breeding duck pairs were observed on approximately 700 wetland basins in 2008 and 2009. A competing model analysis was used to identify local- and landscape-scale habitat characteristics to predict breeding duck pairs on wetland basins. The five most commonly observed species were modeled separately; those species were mallard (Anas platyrhynchos), northern pintails (A. acuta), gadwall (A. strepera ), northern shoveler (A. clypeata) and blue-winged teal (A. discors). At the local scale, wetland basin area, the square root transformation of wetland basin area and wetland basin class were important predictors for all species. Northern pintail, gadwall and blue-winged teal exhibited a strong location effect, occurring more in the northern and eastern portions of the study area. At the landscape scale, the proportion of agricultural lands surrounding a sample basin was associated with the greater abundance of all species. Northern pintail and blue-winged teal breeding pair abundance increased when the proportion of seasonal and semipermanent basin wetland surface area in the landscape around sample basin decreased. Results from this study provide land managers with initial information on where breeding waterfowl are settling across the PPR landscape of north-central Montana. The continuation of this research for several more breeding seasons will enable conservation partners to efficiently target important breeding waterfowl habitat for conservation actions.Item The influence of landscape characteristics on duck nesting success in the Missouri Coteau Region of North Dakota(Montana State University - Bozeman, College of Letters & Science, 2003) Stephens, Scott Eugene; Chairperson, Graduate Committee: Jay J. Rotella; Mark S. Lindberg (co-chair)Because of the importance of nesting success to avian population dynamics, and the extensive and ubiquitous nature of habitat fragmentation, many studies have attempted to address the relationship between fragmentation and nesting success. However, an overall theory of fragmentation effects on nesting success has remained elusive. First, we reviewed published literature to examine fragmentation effects on nesting success at three spatial scales (i.e., edge, patch, and landscape scales). We identified 86 relevant manuscripts that provided 117 individual tests of hypotheses regarding the effects of fragmentation on nesting success. Fragmentation effects were more likely to be detected if fragmentation was examined at a landscape scale and if research was conducted over several years. Next, we examined the influence of habitat and landscape variables on duck nest survival (n ~ 4200 nests) on 18 10.4-km2 sites in the Missouri Coteau Region of North Dakota. We evaluated competing models of nest survival that considered combinations of habitat features measured at nests, within nesting patches, and at multiple landscape scales. We used generalized non-linear mixedmodeling techniques to model nest survival. Information-theoretic techniques were used to select among competing models. Models that included random effects of individual sites and covariates measured at multiple landscape scales were dramatically better than models that included nest-level, patch-level, or landscape-scale covariates measured at a single spatial scale. Nest survival was positively related to the amount of grassland habitat, negatively related to the wetland density and related to the amount of grassland edge in a complex quadratic manner. Finally, we combined our nest survival model with existing models of mallard pairs using spatially-explicit GIS models and applied them to the entire Coteau region of North and South Dakota to guide conservation programs. Important trade-offs existed between pair density and nest survival; source populations were dominated by low pair-density areas while sink populations were dominated by high and medium pair-density areas. Based on the complex suite of factors influencing nest survival, a unifying paradigm of fragmentation across taxa and habitat types may not exist. Thus, research on the species and habitats of interest may be necessary to guide successful conservation efforts.