Weather Monitoring White-tailed Deer Winter Severity Index Volunteer Winter Weather Monitors Required The Manitoba Wildlife Federation, in partnership with Manitoba Sustainable Development - Wildlife and Fisheries Branch, is seeking assistance from local wildlife and fish associations with individuals that have an interest in white-tailed deer biology and in becoming Volunteer Winter Weather Monitors (VWWM). Climate and climate change can have severe impacts on ecosystems and species such as whitetailed deer. In Manitoba, white-tailed deer are at the northern limit of their range and are occasionally susceptible to severe winters causing mortality. Winter severity is influenced by temperature and snow depth, which can effect deer movements, access to quality food and increase energy stress, and can also affect reproductive success rates and individual survival. To monitor the relative severity of winters on white-tailed deer, the Wildlife and Fisheries Branch uses a Winter Severity Index (WSI) as a general measure of winter conditions based on the knowledge that prolonged cold temperatures and deep snow can reduce overwinter survival of white-tailed deer. The current low population status of white-tailed deer in the province is attributed to the recent cycle of severe winters (i.e., 2010/11, 2012/13 and 2013/2014) throughout the deer range. The Duties of a Volunteer Winter Weather Monitor (VWWM) VWWMs will record temperature and snow depth data that is representative of local and regional weather conditions. Data collected from a network of monitoring stations will be assembled and used by the Wildlife and Fisheries Branch to prepare local, regional and province-wide assessments of winter conditions of the deer range. VWWMs must be committed to monitor weather conditions from November 1 to April 30. To obtain an overall assessment of the effects of the winter, VWWMs are required at various locations from east and north to Bissett, south to the U.S. border, west to the Saskatchewan border and north as far as The Pas. The Wildlife and Fisheries Branch is working towards establishing monitoring stations across the provincial deer range, VWWMs are especially needed in Game Hunting Areas where there are currently no winter weather monitoring sites
(see Figure 1). There should be no more than three monitoring stations per Game Hunting Area. Figure 1. Provincial white-tailed deer range Game Hunting Areas in red are those where there are currently no monitoring stations.
Winter Severity Index The methods used for the WSI are repeatable and provides biologists with trend data overtime. The data collected from November 1 to April 30, in the form of daily temperatures ( C), and weekly accumulated snow depths (cm), will: Contribute to building the winter severity index database in Manitoba. Determine the winter severity at various locations within the white-tailed deer range in Manitoba. Temperature Daily temperature data can be collected from local thermometers or the closest automated Environment Canada, The Weather Network, or Manitoba Agriculture Weather Network websites. The following daily temperatures are to be recorded on a weekly data sheet (see Appendix 1). The maximum (warmest) daily temperature ( C). The minimum (coldest) daily temperature ( C). The mean daily temperature ( C). The daily mean is calculated by averaging the daily minimum (coldest) low and maximum (warmest) high temperatures. Snow Depth Measurements Snow depth measurements must be taken once a week in a forested area. Data collection of snow measurements must be initiated once snow remains permanently on the ground and continue through the winter until the ground is snow-free. Measurements will be taken at ground/eye-level. Snow depths measurements shall be recorded along a straight-line transect at 10 permanent sites, with each site located 20 metres (m) apart in untracked (unpacked) snow. The mean value of the 10 measurements is recorded as the snow depth for the station and should be recorded onto the weekly data sheet (see Appendix 2). The following criteria will be used to assist the selection of a snow station transect. A snow station is to be located within a forested area/stand. The snow station and associated transect line is to be located in a forested area/stand of moderate to heavy density with an average tree height being 6 metres or greater.
The terrain should be relatively level with little or no overall gradient, straight-line transects can be set-up in any direction. The transect line should not pass within 40 metres of any clearing, lake, road or other opening which could lead to drifting snow. Materials Required Volunteers shall supply the following materials: 10 metal metric measuring rulers 1 metre in length. 10 metal posts (or substitute - trees or other materials can be used); posts must be a minimum of 3 metres in length, with a diameter of no more than 5 centimetres. Metre rulers are to be attached at ground level. Submission of Data VWWMs must submit week-ending (Sunday) data sheets to the Wildlife and Fisheries Branch by the following Monday. Final year-end reporting data sheets must be submitted no later than two weeks after the winter weather monitoring program has concluded for the year. All data can be submitted electronically or by fax to the Wildlife and Fisheries Branch designate listed below: Herman Dettman, Big Game Biologist Manitoba Sustainable Development Wildlife and Fisheries Branch Email @ herman.dettman@gov.mb.ca Fax 204-945-3077 Analysis and Reporting The Wildlife and Fisheries Branch biologists will analyze the WSI data and the results will be posted on the Wildlife and Fisheries Branch website by June 1. The information will also be shared with the Manitoba Wildlife Federation, local wildlife and fisheries associations and private citizen volunteers that participate. Thank you for participating in this important cooperative program.
Appendix 1 Winter Severity Index - weekly temperature and snow depth data sheets Week Max Temp ( C) Min Temp ( C) Mean Temp ( C) Average Snow Depth cm Week Max Temp ( C) Min Temp ( C) Mean Temp ( C) Average Snow Depth cm Week Max Temp ( C) Min Temp ( C) Mean Temp ( C)
Appendix 2 Winter Severity Index weekly snow depth measurement data sheets Snow depth measurement Snow depth measurement Snow depth measurement Snow depth measurement 1) 1) 1) 1) 2) 2) 2) 2) 3) 3) 3) 3) 4) 4) 4) 4) 5) 5) 5) 5) 6) 6) 6) 6) 7) 7) 7) 7) 8) 8) 8) 8) 9) 9) 9) 9) 10) 10) 10) 10) Average: Average: Average: Average: Snow depth measurement Snow depth measurement Snow depth measurement Snow depth measurement 1) 1) 1) 1) 2) 2) 2) 2) 3) 3) 3) 3) 4) 4) 4) 4) 5) 5) 5) 5) 6) 6) 6) 6) 7) 7) 7) 7) 8) 8) 8) 8) 9) 9) 9) 9) 10) 10) 10) 10) Average: Average: Average: Average: