This study was designed to test the hypothesis that the level of first summer mortality in blue grouse is determined by the condition of the hen and that this in turn determines the level of subsequent fall and spring densities. Early mortality was studied in a series of field and aviary comparisons of chicks on, or from, two areas of Vancouver Island that were in different stages of vegetative succession, following logging and burning. The summer recruitment each year was then compared to annual trends and mortality rates as determined for the breeding populations. No relevant differences were found in the pre-hatch parameters of recruitment (clutch size, fertility, and hatchability) between areas or years. No differences were found in the survival of young between areas, but differences were found between years. There were always sufficient young produced into the fall period to replace the annual losses in the breeding population. The major conclusions are: (1) early mortality does vary between years but does not vary between different habitat types or between areas with different breeding densities, (2) variations in early mortality between years are a result of as yet undetermined parental influences, and (3) this mortality is involved in the regulation of fall numbers, but is not involved in the regulation of subsequent breeding levels in established populations. / Science, Faculty of / Zoology, Department of / Graduate

The primary purpose of keeping blue grouse was to learn to keep them in good health and breed them. New data were obtained on the weights, nutrition, survival, diseases, and behaviour of blue grouse in captivity. They were kept in 3 sizes of pens, 2 feet wide by 4 feet high by 8 feet long, 6 feet wide by 4 feet high by 8 feet long, and 20 feet wide by 10 feet high by 20 feet long. On the basis of plumage condition and reproductive behaviour the medium sized pens were best. The level of protein of the diet of the hens appeared to affect survival and reproductive behaviour. Grouse that were fed a diet with 18 percent protein had better survival and exhibited more reproductive behaviour than grouse fed a diet with 24 or 28 percent protein. Grouse were unable to survive on a diet of dried and pelleted Douglas fir needles. None of the conclusions reached appear applicable to conditions observed in the field. Hens exhibiting reproductive behaviour were sexually imprinted upon humans. The only successful method of mating grouse was to take a male exhibiting sexual display to a squatting female. Artificial insemination was as successful as natural matings in the aviary. The apparent digestibility of the commercial chicken breeder ration varied from 51.2 to 64.9 percent. There was a relationship between the daily consumption of water and body weight. The study of behaviour indicated there was a relationship between the hooting of males and the squatting and egg laying of females. Adult males hooted more than yearlings. The female usually gave a pre-copulatory cry when ready to mate. Males became more aggressive during the breeding season and less aggressive through the summer. The females appeared to have two peaks of aggressive behaviour during the reproductive season. Aggressive behaviour of females may serve to space them in the field during the period of nesting. There may be a period of aggressive behaviour in males during the winter. A partial catalogue of grouse behaviour was made. Photo graphs of postures and sonographs of calls supplement description. / Science, Faculty of / Zoology, Department of / Graduate

This study was designed to follow up previous studies (Bendell and Elliott 1967, Lance 1967, Zwickel and Bendell 1967) which suggested blue grouse regulated their numbers through juvenile mortality over winter, and to examine the population of grouse that lived their entire lives on winter range. Grouse were observed and collected in the sub-alpine of Vancouver Island between May, 1965, and June, 1966. Data from the uplands were compared to grouse on lowland breeding ranges. The major findings were: (1) A low density and apparently stable breeding population lived in the sub-alpine with sex and age ratios and recruitment similar to those of lowland populations. (2) All events of reproduction following spring migration were delayed approximately one month compared to the lowlands. Further, the nesting season was shorter by approximately four weeks. (3) Grouse in the sub-alpine selected open forest and hilly areas as on the lowlands. (4) In winter, some males at least, lived separately from hens and chicks. The males lived in the open forest of the upper elevations of the sub-alpine but the habitat used by the hens and chicks is unknown. (5) The main source of juvenile mortality, and hence population regulation, probably occurred in autumn with first snow fall and/or brood break-up. Late winter behavioral interaction may also be important in regulating numbers. (6) No factor of the sub-alpine was found that could explain the size and success of lowland populations. There was some evidence to suggest that the quality of food in the sub-alpine may.be important to reproductive success on the lowlands. / Science, Faculty of / Zoology, Department of / Graduate

This study was a natural experiment to test an hypothesis that blue grouse populations are regulated by aggressive behavior. Three natural populations were studied during two successive breeding seasons. The environments of the three were essentially the same. The density of one remained stable at 5 territorial males per 100 acres. The density of the second was declining 10% annually and was approximately 6 territorial males per 100 acres. The density of the third was 35 territorial males per 100 acres and had risen to this density in the previous three years. It ceased to rise during the study. The annual mortality of adults was similar in all three. Annual recruitment in any one year, was also similar, however the population which was decreasing showed a lower recruitment over the term of the study. In the population which was increasing in density, more chicks were produced per adult, than in the population which was decreasing. Production in the stable population was intermediate. Males in the increasing population, sang longer into the season than those in the other populations. Males in the increasing population hooted less frequently in response to humans and reacted less aggressively to artificial song than those at the other areas. All grouse in the increasing population were less frequently observed on the ground and were harder to capture than those in the other populations. 'Flush distances' were longer, and the time to flush, was shorter than in the other populations. Threatening calls, "head dips" and "neck stretches", all behavior which indicates aggression were observed more frequently in the decreasing and stable populations. "Flutter flights" and "feather spread displays", gestures which probably also serve as threats, were recorded more often in the declining and stable populations. "Grouch and run", a non-aggressive pattern, was observed more frequently in the increasing population. In the declining population, hens showed more vigorous brood defense than those in the increasing. Chicks were further from the hen in the increasing population, flew more readily, and flew further when flushed. Artificial hen calls caused territorial cocks in all populations to alter their songs similarily. Males at the declining and stable populations advanced more quickly toward the sound. Males in all populations courted a dummy female similarily. When reacting to a mirror, males showed fewer aggressive acts per minute in the increasing population. Behavior, including many types of agonistic behavior can vary between populations. Hostile interactions have the potential of being less severe in the increasing population. This may have caused its increase. However, no cause and effect relationship was demonstrated. / Science, Faculty of / Zoology, Department of / Graduate

No description available.

The pathological effects of infections of Dlspharynx nasuta (Nematoda: Acuariidae) on confined, experiment ally-infected chicks of the blue grouse, Dendragapus obscurus, have been studied. The severity of the infection was found to be directly proportional to the number of worms present and the youth of the host. The development of the lesion produced at the site of infection, the proventriculus of the host, is described and its papillomatous nature confirmed. The previously unknown developmental stages of D. nasuta in the avian host are described and related both to the formation of the lesion and to the disease process. The growth of infected birds, expressed as gain in weight, was less than that of the controls although food intake studies indicated that the amount of food eaten by both groups was comparable. Calcium and phosphorus analyses on bones gave no indication that the mineral metabolism of infected birds was affected although their bones broke more readily than those of the controls. Development of the Juvenal feathers which appear from 3 to 5 weeks of age may be severely retarded. These observations suggest that the protein metabolism of the host is impaired. The numbers of hemocytes of infected grouse fluctuate greatly and show two critical low periods. The first, occurring immediately after infection, can be correlated with the invasion of the larvae and possibly to a substance secreted by them. The second occurs 2 to 3 weeks after initial infection and can be correlated with local irritation and hemorrhages and perhaps the moult of the larvae. Chronic hematological symptoms are anemia and leucocytosis. The latter is characterized by heterophil ia, eosinophilopenia, lymphocytosis of small forms and lymphopenia of the larger forms. The presence of circulating antibodies for D. nasuta was not demonstrated with the techniques used. The evidence suggests that the host tissue reaction may be an allergic response. Several ecological questions concerning the survival of D. nasuta during the winter months, temperature for larval development in the intermediate host, longevity of adult D. nasuta in the definitive host, infection and reinfection of adult blue grouse, are considered. In the laboratory, infections of 16 and 22 worms, administered to the host before 2 weeks of age, were fatal. Results of these experiments indicate that D. nasuta is a debilitating pathogen which may prove fatal and, may act as a controlling factor of natural grouse populations. / Science, Faculty of / Zoology, Department of / Graduate

A general property of animal populations is their failure to continue increasing in number indefinitely, even when the habitat may contain enough resources to support more animals than are present at the time. Certain populations of blue grouse have expressed this property by failing to increase when the habitat has undergone changes that have produced striking increases in past cases. Other populations have expressed it by arresting their increase before the resources of the habitat were exhausted. In blue grouse populations on Vancouver Island, adult mortality is constant and it is restricted recruitment that has held these populations stable in the periods they have been studied, even though sufficient young have been produced to support an increase. The hypothesis that the behavior of territorial adult males affects the local occurrence of recruits and other grouse in general on the summer range was tested by studying dispersion during the breeding period. Information on dispersion and social behavior were obtained from nine grouse fitted with miniature radio transmitters. Data from non-instrumented birds supplement this work. The principal finding is that there was no evidence of social interaction causing females and immature males to occur in special places, and that no interaction of a sort that could affect recruitment occurs between blue grouse on their summer range. It is alternatively suggested that such behavior occurs in winter. Other conclusions are that the onset of estrus induces hens to seek out and become localized near a mate, that several hens may seek out the same mate, and that no lasting pair-bonds are formed. Each type of reproductive activity in blue grouse has a distinctive movement pattern, and perhaps movement rate, associated with it. Excepting for hens In estrus who briefly seek out mates, and some yearling males who are prevented by adults from remaining on territories, movements and local occurrence within the breeding range are unaffected by social interaction with other grouse. / Science, Faculty of / Zoology, Department of / Graduate

The dispersion of a population of blue grouse was analyzed using data from a breeding range on east-central Vancouver Island. During the summers of 1959-1962, the locations, densities, habitat preferences, and behaviour of grouse were studied using several habitats with varying densities of vegetation. A removal experiment was performed in different habitats to test the effect of interaction and selection of habitat on the dispersion of males. All adult males and a few yearling males were territorial, and territories were spaced in a near-uniform pattern. Within a given season, males removed from their territories were seldom replaced by other adults, suggesting that no surplus of non-territorial adults was present. About half of the yearling males were prevented from establishing territory by the presence of adults, and these yearlings were attracted to the vicinity of territorial males. The location of territories by newly-adult males did not depend significantly on the number of territories already present, even though the tendency toward uniform spacing was preserved. Comparison with other studies indicated that territory size and possibly the fraction of yearling males in the population were inversely related to the density of males. Females restricted their movements while on the breeding range but were not territorial. No pair-bonds were observed but females stayed near territorial males prior to nesting. After the hatch, the locations of females and broods bore no relation to each other or to the positions of males. Interaction apparently had no effect on breeding numbers. All birds preferred sparse vegetation to dense. When compared to randomly-chosen points, territories were found more often in areas with sparse vegetation, elevated points, and patches of open ground. Within open habitats, nests were usually located where cover by logs, stumps, and ground-level vegetation was high, and cover by dead plants and litter was low. Broods were associated with moist areas and other areas having heavy cover by vegetation at the ground level. Chicks apparently dispersed widely between their first and second summers. In their third summer, males usually returned within one-half mile of the positions they used as yearlings. Once territories were established, the owners returned to them in succeeding summers. Females one year and older showed a fairly accurate return to their previous locations. The dispersion was described somewhat theoretically by considering the summer population to be grouped into two types of aggregations. The first, found in the earlier half of the summer, was caused by the attraction of yearling males and lone females to territorial males. Later, hens with their broods were the dominant groupings. The spacing, movements, and habitat preferences seemed to be adaptations allowing such populations to rapidly exploit new habitats. / Science, Faculty of / Zoology, Department of / Graduate

The present study demonstrates that blue grouse on Vancouver Island are infected with two species of Haemoproteus, probably two species of Leucocytozoon and a species of Trypanosoma. Haemoproteus dendragapi n.sp. is described from the Nanaimo Lakes Area. The growth rate of H. canachites gametocytes is much more rapid than that described by Fallis in Ontario. The very young tissue stages of H. canachites are described from lung preparations of grouse chicks. The life cycle of Leucocytozoon bonasae has been completed by using a new vector, Cnephia minus. As reported by Fallis in Ontario, Simulium aureum has been found to be a vector of L. bonasae on Vancouver Island. This study has verified Woodcock's often ignored hypothesis that the morphology of the gametocyte-host cell complex changes with age of infection. A probable new species of Leucocytozoon is described from the Campbell River Area. In-vitro culture of the trypanosome from grouse blood has been carried out. A yearling blue grouse has been successfully infected by inoculation of metacyclic trypansomes from the culture. / Science, Faculty of / Zoology, Department of / Graduate

The effects of herbicidal spraying upon a North Central Utah blue grouse population were studied. Baseline data were obtained in 1970 and 1971 prior to the spraying on June 2, 1972. The spraying was done to control wyethia (Wyethia amplexicaulis) and black sage (Artimesia nova) which covered 48 percent and 20 percent of the study area respectively. No differences in blue grouse numbers occurred following spraying with 17 to 20 broods using the area in 1972 compared to 18 to 20 broods in 1971. Total population of blue grouse each year was between 90 and 104 birds. Distribution of blue grouse changed, with the birds using areas with trees and shrubs following spraying rather than open areas that were sprayed. There was significantly more black sage on the control area than the spray area. These differences began before spraying, however, and cannot be attributed solely to the spray. No differences occurred in insect numbers or songbird use of the spray and control area.