Time filter

Source Type

Fort Nelson, Canada

Poole K.G.,Aurora Wildlife Research | Bachmann K.D.,Tembec Inc. | Bachmann K.D.,CBA Ltd. | Teske I.E.,Environment Canada
Western North American Naturalist | Year: 2010

In most populations of mountain goats (Oreamnos americanus), mineral lick use is an essential part of the ecology of the species. In many areas, the distribution and use of licks in the landscape is poorly known, rendering planning for resource development difficult, We examined lick use by 28 GPS radio-collared mountain goats in 2 study areas in southeastern British Columbia during 20042005, Viewing collar-location movements on digital orthophotos, we assumed goat use of 6 previously known and 10 suspected mineral licks. Field visits verified that 9 of the 10 suspected sites were mineral licks, Thirteen of the 1.5 licks used by collared goats were within forests with commercial harvesting potential. All but 3 of the licks were ≤600 m from the closest logging block, and 5 licks were <100 m away, Number of annual visits to licks by individual goats ranged from 0 to 9. Goats often moved considerable distances (up to 17.3 km) to visit licks. Most visits by males occurred between early May and late June (median 9 June), and most visits by females occurred between early June and mid-July (median 21 June). Mean time spent at licks on each visit was 1.5 days for females and 1.6 days for males. Most of the licks were characterized by numerous cavities dug under trees (which we term "lick trees"). Using GPS collars, we were able to collect data on lower-elevation mineral licks not previously known to researchers. Source

Adamczewski J.,Natural Resources Canada | Gunn A.,368 Roland Road | Poole K.G.,Aurora Wildlife Research | Hall A.,Arctic Inc | And 2 more authors.
Arctic | Year: 2015

The Beverly herd was one of the first large migratory herds of barren-ground caribou (Rangifer tarandus groenlandicus) defined in northern Canada on the basis of annual return of breeding females to traditional calving grounds near Beverly Lake in Nunavut. In 1994, herd size was estimated at 276 000 ± 106 600 (SE) adult caribou, but monitoring was minimal from 1994 to 2007. The next calving ground survey in 2002 revealed that caribou densities had dropped by more than half since 1994; annual surveys following from 2007 to 2009 demonstrated an extreme decline in numbers of calving cows, and by 2011, no newborn calves were seen there. We examine two possible explanations for the declining use of the traditional Beverly calving grounds from 1994 until their abandonment by 2011. One explanation is that a true numerical decline in herd size occurred, driven in at least the later stages by low cow survival and poor calf productivity, which led the remaining Beverly cows to switch to the neighbouring Ahiak calving ground 250 km to the north in 2007-09 and join that herd. An alternative explanation is that the decline on the traditional Beverly calving grounds was largely due to a distributional shift to the north of the Beverly herd that may have begun in the mid-1990s. We suggest that the former explanation is the more likely and that the Beverly herd no longer exists as a distinct herd. We acknowledge that gaps in monitoring of Beverly and Ahiak caribou hamper definitive evaluation of the Beverly herd’s fate. The large size sometimes achieved by barren-ground caribou herds is not a guarantee of persistence; monitoring shortfalls may hamper management actions to address declines. © The Arctic Institute of North America. Source

Poole K.G.,Aurora Wildlife Research | Cuyler C.,Greenland Institute of Natural Resources | Nymand J.,Greenland Institute of Natural Resources
Wildlife Biology | Year: 2013

Abundance estimates are important to management of most harvested species of wildlife. In West Greenland, recent estimates of barren-ground caribou Rangifer tarandus groenlandicus population size have been derived from aerial surveys conducted in early March of numerous short (7.5 km) transects that focused on obtaining high detection probabilities. The resultant study area coverage was low (≤ 1.6%), in part due to the survey design. In this article, we conducted a critical review of the current West Greenland caribou survey methodology using data from past surveys and recent GPS collar data, and present recommendations to improve the methodology. On an annual basis, movement rates of collared females were lowest in March, supporting survey timing. March distribution of collared caribou, however, differed markedly between 2009 and 2010, indicating that stratification flights prior to each survey are required to produce the most accurate and precise estimates. A viewshed analysis in GIS supported the use of a 300-m strip width, but demonstrated that the current 15-m survey flight altitude resulted in 4-5% availability bias due to the portion of the strip width hidden by topography and out of sight of observers, and a corresponding nil detection probability for caribou in these areas. A 30-m or 45-m flight height may be more appropriate to reduce the availability bias in this rugged terrain. Examination of the population composition data collected during and after abundance estimates suggested that robust calf:cow and bull:cow ratio data could be obtained with less sampling effort distributed proportionate to the population density. We suggest that systematic strip transects should be considered to increase survey coverage; this design would increase survey efficiency (ratio of helicopter time to coverage) and inherently increase precision. Distance sampling collected by group would be an improvement over the current negatively biased, transect-total method to calculate detection probabilities. Managers should ensure that sufficient resources are available to obtain robust estimates of abundance and composition of West Greenland caribou. These recommendations may be applicable to other areas in which ungulate populations exist in heterogeneous habitats with low sightability. © 2013 Wildlife Biology, NKV. Source

Boulanger J.,Integrated Ecological Research | Poole K.G.,Aurora Wildlife Research | Gunn A.,368 Roland Road | Wierzchowski J.,Consulting Inc.
Wildlife Biology | Year: 2012

Wildlife species may respond to industrial development with changes in distribution. However, discerning a response to development from differences in habitat selection is challenging. Since the early 1990s, migratory tundra Bathurst caribou Rangifer tarandus groenlandicus in the Canadian Arctic have been exposed to the construction and operation of two adjacent open-pit mines within the herd's summer range. We developed a statistical approach to directly estimate the zone of influence (area of reduced caribou occupancy) of the mines during mid-July-mid-October. We used caribou presence recorded during aerial surveys and locations of satellite-collared cow caribou as inputs to a model to account for patterns in habitat selection as well as mine activities. We then constrained the zone of influence curve to asymptote, such that the average distance from the mine complex where caribou habitat selection was not affected by the mine could be estimated. During the operation period for the two open-pit mines, we detected a 14-km zone of influence from the aerial survey data, and a weaker 11-km zone from the satellite-collar locations. Caribou were about four times more likely to select habitat at distances greater than the zone of influence compared to the two-mine complex, with a gradation of increasing selection up to the estimated zone of influence. Caribou are responding to industrial developments at greater distances than shown in other areas, possibly related to fine dust deposition from mine activities in open, tundra habitats. The methodology we developed provides a standardized approach to estimate the spatial impact of stressors on caribou or other wildlife species. © 2012 Wildlife Biology, NKV. Source

Poole K.G.,Aurora Wildlife Research | Reynolds D.M.,British Columbia Ministry of forests | Mowat G.,British Columbia Ministry of forests | Paetkau D.,Wildlife Genetics International
Journal of Wildlife Management | Year: 2011

Non-invasive collection of tissue samples to obtain DNA for microsatellite genotyping required to estimate population size has been used for many wildlife species but rarely for ungulates. We estimated mountain goat (Oreamnos americanus) population size on a mountain complex in southwestern British Columbia by identification of individuals using DNA obtained from fecal pellet and hair samples collected during 3 sampling sessions. We identified 55 individuals from 170 samples that were successfully genotyped, and estimated a population of 77 mountain goats (SE = 7.4). Mean capture probability was 0.38 (SE = 0.037) per session. Our technique provides one of the first statistically rigorous estimates of abundance of an ungulate species using DNA derived primarily from fecal pellets. Our technique enables managers to obtain minimum counts or population estimates of ungulates in areas of low sightability that can be used for conservation and management. Copyright © 2011 The Wildlife Society. Source

Discover hidden collaborations