This study attempts to explain changes in abundance of rock ptarmigan (Lagopus mutus) at Eagle Creek, Alaska. It includes an analysis of population data collected from 1960 to 1969, and a test of an hypothesis: that there were no differences in the quality (survival, growth, behaviour) of rock ptarmigan chicks between years that influenced spring densities. Spring densities fluctuated between 1960 and 1969, reaching peaks in 1962 and 1968. This was the result of an orderly and generally synchronous change in the loss of birds (primarily juveniles) in winter, accompanied by changes in the production of young. Both acted together in most years to either increase or decrease numbers. Each contributed approximately equally to changes in total annual loss. Changes in the production of young were primarily caused by parallel changes in both clutch sizes and nest failures. Population regulation by direct extrinsic control appeared unlikely. Other than weasel predation on nests, no environmental factor external to the population itself appeared sufficient to explain changes in winter loss of juveniles or clutch size loss, or their synchrony. These results suggested that some internal process within the population must have been important in changing the abundance of partmigan. I tested the aforementioned hypothesis in 1967, 1968, and 1969 by examining chicks both in the wild, and in captivity. Survival, growth, and behaviour of chicks all varied between years. Changes in survival were apparently determined by unidentified parental influences (genetic or physiological) rather than by the direct influence of the environment. Growth rates were similar between years in captivity, but not in the wild, suggesting that environmental influences must have had some effect. However, neither the changes in survival of chicks in summer, nor in growth rates, could be implicated in altering subsequent spring breeding densities. Levels of agonistic and aggressive behaviour in successive cohorts of aviary chicks differed. In the similar environment of the aviary each year, these behavioural changes were attributed to undetermined parental influences (genetic or physiological). These changes in aggressive-agonistic behaviour offer the best possible explanation of changes in the. population parameters most important in altering spring breeding densities. / Science, Faculty of / Zoology, Department of / Graduate

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Thesis (M. Sc.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on Jan. 14, 2010). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Department of Biological Sciences, University of Alberta." Includes bibliographical references.

Master of Science / Department of Biology / Brett K. Sandercock / Translocations are a useful management tool for restoring wildlife species to their native ranges, but require post-release monitoring to determine project success. We report results of a 4-year effort to reestablish a breeding population of Evermann's Rock Ptarmigan (Lagopus mutus evermanni) on Agattu Island in the Aleutian Archipelago, Alaska. This endemic subspecies of ptarmigan was extirpated from most of the Near Islands by introductions of arctic fox by fur traders, and natural recolonizations did not occur after fox eradication. All females surviving the 2-week post-release period attempted to nest but initiated clutches later in the season and laid fewer eggs than resident females. Nest success was similar for resident and translocated females. Brood survival was greater for translocated than resident females and differed significantly; however, brood survival varied among years and was reduced by adverse weather conditions in 2006. Seasonal survival of radio-marked birds during the breeding season was 100% for translocated and resident ptarmigan. Over-winter mortality resulted in a low return rate in 2006. Returning birds in 2006 showed strong site fidelity and nest locations in two consecutive years were closely spaced. We examined nest site selection and determined brood movements and home range size of recently translocated and resident females. Nest sites of translocated females averaged 4.2 km from their respective release location and were not different from nest locations of resident females with regard to topographical features. Female nest site selection was influenced by percent composition of rock and forb coverage but was unaffected by slope, aspect, or general habitat. Broods of both resident and translocated females made movements to higher elevations after hatching. While size of brood home range was similar for resident and translocated females, distances traveled between the nest site and the arithmetic center of the brood home range were greater for translocated females. Overall, we conclude that translocations are an effective technique for reestablishing island populations of Rock Ptarmigan. Our study provides successful methods which may benefit future projects to reestablish endemic populations of ptarmigan and landbirds elsewhere in the Aleutian Islands.

Willow grouse ( Lagopus lagopus) and rock ptarmigan (Lagopus muta) are popular game birds in Sweden. I have analysed hunting statistics from Jämtland county in Sweden and investigated if there is a significant correlation between willow grouse density and Catch-Per-Unit-Effort (CPUE) by nationalities and type of permits. The included nationalities were Swedish, Nordic and non-Nordic hunters. Type of permits that were analysed were day-, municipality and county permits. There was no correlation between the grouse density and CPUE variables. However, significant correlations were found when correlating yearly number of harvested grouse  with the CPUE variables. For willow grouse, significant correlations were found between Swedish, Non-Nordic, day and municipality permit hunters and for rock ptarmigan, Swedish, Nordic, day and municipality permit hunters. I also found that international hunters was more effective than Swedish hunters, as well as hunters with day permit, which was true for both species. There were also differences between the CPUE variables between two time periods, 2004-2012 and 2013-2021. In the second period, the CPUE of Swedish hunters, day and municipality permit hunters have decreased for willow grouse. The CPUE also decreased for non-Nordic during the second period for rock ptarmigans. Significant difference in hunting pressure were also found between the two time periods, where the later period had slightly higher hunting pressure than the first period. The results of this study strengthened previous studies where no correlation has been found between the grouse density and CPUE.

From an ecological perspective, knowledge of demographic history is highly valuable because population size fluctuations can be matched to known climatic events, thereby revealing great insight into a species’ reaction to past climate change. This in turn enables us to predict how they might respond to future climate scenarios. Prominently, with the advent of high-throughput sequencing it is now becoming possible to assemble genomes of non-model organisms thereby providing unprecedented resolution to the study of demographic history and speciation. This thesis utilises four species of grouse (Aves, subfamily Tetraoninae) in order to explore the demographic history and speciation within this lineage; the willow grouse, red grouse, rock ptarmigan and the black grouse. I, and my co-authors, begin by reviewing the plethora of methods used to estimate contemporary effective population size (Ne) and demographic history that are available to animal conservation practitioners. We find that their underlying assumptions and necessary input data can bias in their application, and thus we provide a summary of their applicability. I then use the whole genomes of the black grouse, willow grouse and rock ptarmigan to infer their population dynamics within the last million years. I find three dominant periods that shape their demographic history: early Pleistocene cooling (3-0.9 Mya), the mid-Brunhes event (430 kya) and the last glacial period (110-10 kya). I also find strong signals of local population history – recolonization and subdivision events – affecting their demography. In the subsequent study, I explore the grouse dynamics within the last glacial period in more detail by including more distant samples and using ecological modelling to track habitat distribution changes. I further uncover strong signals of local population history, with multiple fringe populations undergoing severe bottlenecks. I also determine that future climate change is expected to drastically constrict the distribution of the studied grouse. Lastly, I use whole genome sequencing to uncover 6 highly differentiated regions, containing 7 genes, hinting at their role in adaptation and speciation in three grouse taxa. I also locate a region of low differentiation, containing the Agouti pigmentation gene, indicating its role in the grouse plumage coloration.