Vulnerability of Willow Ptarmigan to Hunting

Bergerud, Arthur T.; Columbia, British

doi:10.2307/3799012

Cited by 7 publications

(7 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Bowman and Robel (1977) also reported greater mortality for juvenile than adult prairie chickens, particularly during the fall dispersal. Additionally, we found evidence of negative effects of differential susceptibility to harvest on the harvest-age ratio only in galliforms (Bergerud 1970, Roseberry and Klimstra 1992, Durbian et al 1999. Clearly, if both differential susceptibility to harvest and survival existed in the populations we studied, we would have expected an exaggeration of their negative effect on the harvest-age ratio as the hunting season progressed rather than a suppression of the effects.…”

Section: Survival and Harvest Effectssupporting

confidence: 49%

“…We maintain that this was unlikely under the conditions occurring during the Nebraska hunting seasons we evaluated. First, older juveniles might be more wary or physically capable of evading hunters and therefore less susceptible to harvest than younger juveniles in Galliformes (Helminen 1963, Gallizioli 1967, Mercer 1967, Bergerud 1970. Therefore, in the long Nebraska hunting season (3.5 months), we can reasonably assume that juveniles would have adequate time to mature, gain experience with hunting, and take on a harvest rate similar to adults.…”

Section: Survival and Harvest Effectsmentioning

confidence: 99%

“…The percentage of juvenile birds in the harvest has been shown to decline as the hunting season progressed for greater prairie-chickens (Durbian et al 1999), ring-necked pheasants (Phasianus colchicus; Kimball 1948, Eberhardt andBlouch 1955), northern bobwhites (Colinus virginianus; Roseberry and Klimstra 1992), Gambel's quail (Callipepla gambelii; Gallizioli and Swank 1958), ruffed grouse (Bonasa umbellus; Davis and Stoll 1973), willow ptarmigan (Lagopus lagopus; Bergerud 1970), capercaillie (Tetrao urogalus; Helminen 1963), and black grouse (Lyrurus tetrix; Helminen 1963). All of these authors believed that differential vulnerability to harvest was at least partially responsible for the decline they detected.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Validity of Prairie Grouse Harvest-Age Ratios as Production Indices

Flanders-Wanner

White

McDaniel

2004

Journal of Wildlife Management

View full text Add to dashboard Cite

The ratio of juveniles to adults in the fall harvest is a common index of production for Galliformes. The percentage of juvenile birds in the harvest has been shown to decline as the hunting season progressed for many galliforms, resulting in a biased index of production. Therefore, we used wing samples of plains sharp‐tailed grouse (Tympanuchus phasianellus jamesi) and greater prairie‐chickens (T. cupido pinnatus) from 4 public land areas in the Nebraska Sandhills, Nebraska, USA, to assess the potential for bias in harvest‐age ratios across time. We hypothesized that the ratio of juveniles to adults in the harvest could change over time if susceptibility to harvest and/or fall survival were different between the juvenile and adult prairie grouse (Tympanuchus spp.) in the Nebraska populations. We found no change in the harvest‐age ratio over time in either the sharp‐tailed grouse or greater prairie‐chicken data. Our findings were consistent with the published literature on harvest‐age rates for sharp‐tailed grouse but inconsistent with the greater prairie‐chicken literature. Therefore, we maintain that analysis of the harvest data for bias due to a changing harvest‐age ratio as the hunting season progresses is an essential adjunct to subsequent analysis or comparisons of production indices based on harvest‐age ratios. In addition, limitations of harvest‐age ratios must be known and care must be taken to minimize other potential biases before using harvest‐age ratios as an index to production.

show abstract

Section: Survival and Harvest Effectssupporting

confidence: 49%

Section: Survival and Harvest Effectsmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Validity of Prairie Grouse Harvest-Age Ratios as Production Indices

Flanders-Wanner

White

McDaniel

2004

Journal of Wildlife Management

View full text Add to dashboard Cite

show abstract

“…The sparse radiotelemetry data required us to pool information and assume a common vulnerability coefficient for both young-of-the-year and older birds. However, numerous investigators have either found or suggested that juvenile upland game birds have higher vulnerability to harvest than adult birds (Bergerud 1970, Davis and Stoll 1973, Shupe et al 1990, Durbian et al 1999. To assess the sensitivity of our abundance estimates to the assumption of equal vulnerability, we repeated the population reconstruction after setting the juvenile vulnerability coefficient to be twice that of adults (i.e., 2c).…”

Section: Model Assumptionsmentioning

confidence: 99%

Using Statistical Population Reconstruction to Estimate Demographic Trends in Small Game Populations

Broms¹,

Skalski

Millspaugh

et al. 2010

J Wildl Manag

View full text Add to dashboard Cite

Statistical population reconstruction offers a robust approach to demographic assessment for harvested populations, but current methods are restricted to big‐game species with multiple age classes. We extended this approach to small game and analyzed 14 years of age‐at‐harvest data for greater sage‐grouse (Centrocercus urophasianus) in Oregon, USA, in conjunction with radiotelemetry data to reconstruct annual abundance levels, recruitment, and natural survival probabilities. Abundance estimates ranged from a low of 26,236 in 1995 to a high of 39,492 in 2004. Annual abundance estimates for adult males were correlated with a spring lek count index (r = 0.849, P < 0.029). We estimated the average annual harvest mortality for the population to be 0.028, ranging from 0.021 to 0.031 across years. We estimated the probability of natural survival of adult females to be 0.818 ( = 0.052), somewhat higher than that of adult males (Ŝ = 0.609, = 0.163). Our precision in reconstructing the population was hampered by low harvest rates and the few birds tagged in the radiotelemetry investigations. Despite these issues, our analysis illustrates how modern statistical reconstruction procedures offer a flexible framework for demographic assessment using commonly collected data. This approach offers a useful alternative to small‐game indices and would be most appropriate for species with 5 or more years of age‐at‐harvest data and moderate‐to‐heavy harvest rates.

show abstract

“…In these cases, such change can bias estimates of productivity derived from harvested wing collections (Flanders‐Wanner et al 2004). The ratio of I:A birds in the harvest has been shown to decline through the hunting season for many Galliformes (Gallizioli and Swank 1958, Bergerud 1970, Roseberry and Klimstra 1992, Durbian et al 1999), but remained stable in some cases (DeStephano and Rusch 1986, Flanders‐Wanner 2004). For forest grouse, few studies of harvest data have been evaluated for changes in the I:A ratio during hunting seasons.…”

mentioning

confidence: 99%

Temporal changes in age and sex ratios of forest grouse harvested in northeastern oregon

et al. 2011

View full text Add to dashboard Cite

Ratio of immature (young of the year) grouse to adult birds (I:A) in the harvest of upland game birds is commonly used as an index to annual reproduction; however, I:A ratios can vary as the season progresses producing biased estimates. We analyzed I:A ratios in the daily harvest of dusky grouse (Dendragopus obscurus) and ruffed grouse (Bonasa umbellus) in northeastern Oregon over 28 years and found that I:A ratios in the harvest declined for both species as the hunting season progressed. We also analyzed ratios of adult female to adult male (AF:AM) grouse to determine if female and male grouse were harvested in equal numbers throughout the harvest season. We found that more males than females of both species were harvested, but that AF:AM ratio of both dusky and ruffed grouse did not change during most of the hunting season. Approximately 50% of the annual harvest occurred during the first 14 days of the hunting season. Therefore, we recommend using the ratios of I:A birds in the first 14 days of the harvest season as the best index to annual reproduction of forest grouse in northeast Oregon. ß 2011 The Wildlife Society.

show abstract

Vulnerability of Willow Ptarmigan to Hunting

Cited by 7 publications

References 3 publications

Validity of Prairie Grouse Harvest-Age Ratios as Production Indices

Validity of Prairie Grouse Harvest-Age Ratios as Production Indices

Using Statistical Population Reconstruction to Estimate Demographic Trends in Small Game Populations

Temporal changes in age and sex ratios of forest grouse harvested in northeastern oregon

Contact Info

Product

Resources

About