Moose Winter Range Mapping, Boundary Forest District, British Columbia

Transcription

1 Moose Winter Range Mapping, Boundary Forest District, British Columbia Les W. Gyug, Registered Professional Biologist Okanagan Wildlife Consulting Ensign Way Westbank, B.C. V4T 1T9 Prepared for B.C. Ministry of Water, Land and Air Protection, Okanagan Region Penticton, B.C. February 1 1,2003

2 TABLE OF CONTENTS INTRODUCTION... 3 METHODS... 3 SUITABILITY MAP DEVELOPMENT... 4 Project Area... 4 Season... 4 Model Summary... 4 Ungulate Inventory Data... 5 WINTER RANGE SUITABILITY MAPPING... 5 RECOMMENDATIONS... 6 LITERATURE CITED... 6 List of Figures Figure 1. Broad Ecosystem Inventory -based moose winter range mapping compared to moose winter range management units proposed in fall 2002, Boundary Forest District, British Columbia (: Figure 2. Aerial ungulate survey routes from February 2001 and March 2002, and previously known moose observations in Boundary Forest District, British Columbia Figure 3. Aerial ungulate survey routes on December 20,2002, and February 6,2003, Boundary.... Forest District, Bntish Columbia Figure 4. Moose observations during aerial surveys, December 20,2002, and February 6,2003, Boundary Forest District, British Columbia Figure 5. Moose winter range suitability map for Boundary Forest District, I Acknowledgements This project and report was completed under contract to the British Columbia Ministry of Water, Land and Air Protection, Okanagan Region. This project only came about because funding was freed up from moose censuses in Management Units 8-23 and 8-24 which did not require their full budgets. Brian Harris served as contract monitor. The report and maps also benefited from discussions with MWLAP personnel including Les Molnar, Grant Furness, Brian Harris and Tom Ethier. Brain Harris and Bruce Ryder assisted as observers on aerial survey flights. Helicopter services were provided by John Kennedy and Matt Callaghan of Kelowna (Kokanee) Helicopters.

3 INTRODUCTION This is a continuation of the previous ungulate winter range mapping exercise begun in 2002 by Okanagan Wildlife Consulting (Gyug 2002b) under contract to the Okanagan Region (Region 8) of the Ministry of Water, Land and Air Protection (MWLAP). Examination of the results of that project for moose in the Boundary Forest District were not deemed successful in that the mapped winter range took in far too much area, much of which is unoccupied by moose in the winter (Figure 1). Initial attempts by WLAP staff and licensees clearly showed there were large areas for which there was little agreement on whether an area was moose winter range or not largely because of lack of data (see Figure 1). This project was intended to refine the existing model of moose winter range in the Boundary based on new aerial survey data. Broad Ecosystem Inventory (BEI) mapping (1 :250,000 scale based on Landsat and Biogeoclimatic Ecosytem Classification (BEC) Zones) will never be able to map moose winter range in enough detail to provide for on-the-ground habitat management. Critical factors for moose winter range mapping such as wetlands and soil capacity for palatable shrub growth are not covered by BE1 mapping. Therefore this project made modifications to the existing Moose Ratings for BE1 by applying survey data to map out the currently occupied moose winter range in the Boundary. The only more detailed TEM or PEM products was the Granby pre-tem biophysical mapping covering 30% of the district. However, this has never been interpreted for moose, but certainly could be, but would only cover about a quarter of the moose range in the Boundary. As a result, this project mapped current winter range suitability for moose in the Boundary Forest District, rather than capability, because the results are based largely on interpretation of aerial survey data. METHODS Resource Inventory Committee standards (Appendix G, British Columbia Ministry of Environment, Lands and Parks 1999) were used to develop the winter range maps of Gyug (2002b) at 1 :250,000 scale using a BE1 base. Other sources of information applied to this project were GIs-based coverages the Digital Slope Model broken into polygons based on 25-m pixels with slope classifications of 0-35%, 45-90%, %, > 120% provided by M WLAP, and the Okanagan ungulate aerial survey database provided by MWLAP. Additional information from Mule Deer classification counts in the southern part of the district on December 20,2002 (Gyug 2003) and from one day of aerial survey counts specifically for moose on February 6,2003, were added to the Okanagan aerial survey database. The Okanagan ungulate inventory data consisted of all the aerial ungulate inventories flown in the region between 1968 and early This consisted of 144 flights (some of which were multiple flights) with 2965 location records of individual animals (which includes all ungulates, not just moose). Additional maps and information consulted included the moose winter range stratification for MU 8-14 (Gyug 2001) and the Central Okanagan (Poole et al. 1999).

4 The final maps provided here are estimates of current winter range suitability for moose in the Boundary Forest District using the 6-class RIC rating system. However, the Very Low (5) (1-5% of baseline maximum moose suitability) and the Nil (6) classes were left out of consideration. In addition, the maps do not attempt to include all Low suitability habitat. To be consistent throughout the southern interior, the lowest of the Low areas are left out of consideration. Using RIC classes, Low takes in areas with 6-25% of maximum suitability, but the lowest areas below 10% of maximum suitability were actually requested for this winter range mapping (Gyug 2002b). Therefore there will be some areas of isolated moose winter occurrence which are not included on these maps. All output coverages used in the project are available in digital ARC shapefile format in B.C. Albers projection. SUITABILITY MAP DEVELOPMENT Project Area: Boundary Forest District which is in Okanagan Region (Region 8) of the Ministry of Water, Land and Air Protection (MWLAP). Season: Winter. This is defined as November to March for the Southern Interior (Appendix B, British Columbia Ministry of Environment, Lands and Parks 1999). However, only December to March was considered here. In the Southern Interior, for moose in particular, most moose remain on summer ranges into November based on data from the Okanagan Connector Freeway telemetry project (Simpson et al. 1995). Depending on how quickly deep winter snow builds up, most moose will move towards winter ranges during December. In addition, this project only sought to map 90% of the winter ranges, without covering 100% of the areas where these ungulates could be in any winter. The 6-class rating system used for ungulate ecosystern/habitat mapping specifies that Class 4 (=Low) rating is given to areas that achieve 6-25% of the maximum density (i.e. includes down to 95% of the winter range, rather than to 90%). This breakpoint is slightly different than desired for this project. Therefore a more conservative estimate of winter was used as December to March, which would not include some of the outlying winter range areas that are only used for small portions of the early winter. Model Summary: Species accounts from other projects were appended to Gyug (2002b) but a short summary of the model rationale is presented here. Moose are browsing ungulates that depend on high quantities of palatable shrubsprincipally willow - to survive the winters. Snow depths >70 cm are considered extremely limiting to moose. Winter temperature tolerances are between -25C and -5C with heat stress starting at -2C. Moose are found throughout the region but reach highest winter capabilities at midelevations in the MSxk and IDFdk. Slightly lower in capabilities are the MSdm2 and the IDFxh. The ESSF and AT zones have almost no winter capability because of deep snows. The upper MSdm2 can also have snow depths that are very limiting to moose in the winter. Areas with greater winter snows at the east edge of the region (SFH, SHH ecosections; ICH BEC subzones) can be limiting to moose because of winter snow accumulations at middle to upper elevations.

5 The ICHdw is less limiting than the wetter ICHm and ICHw zones with a wider range of elevations and habitats used in the IDFdw than in the ICHm or ICHw zones. However, the ICHrnk is a very widespread BEC subzone with some parts of it equivalent to plateau MSdm where it has been mapped above the IDF, and other parts more similar to valley bottom ICH types, and is therefore difficult to generalize for moose modeling. The lowest BEC zones, the BG and PP, are of limited usefulness to moose because of winter temperatures that are generally above the winter tolerances of moose. Ungulate Inventory Data The previously available moose location information is shown on Figure 2. New ungulate inventory data for this project came from a mule deer classification flight on December 20,2002, and from a moose habitat stratification flight (equivalent to RIC "encounter transect") on February 6,2003, both by helicopter. Survey routes for these flights are shown on Figure 3. In addition, the negative data (i.e. areas where there were no moose or fresh moose tracks) from flights made in February 2001 (425 km route surveyed in Boundary, Gyug 200 l), March 2002, (541 km route surveyed in Boundary, Gyug 2002a) and the two flights mentioned above were considered in the suitability mapping. 32 moose at 21 locations were seen on the February 6 flight, and notes made on tracks seen at 150 locations in the 645 km route surveyed (Figure 4). 3 moose at 2 locations were seen on the December 20 flight with no note made of any fresh moose tracks on the 223 krn route surveyed (Figure 4). WINTER RANGE SUITABILITY MAPPING The moose BE1 winter range maps of Gyug (2002b) were altered to cover only those areas occupied by moose in the winter, with suitability estimated based on comparisons to stratification flights and expected moose densities compared to provincial benchmarks. Most slopes of >45% were excluded from the areas of suitability. The only area of Class 2 moose winter range suitability (Moderately High % of provincial benchmark density) was at Arlington Hills area on Highway 33 (Figure 5). The only area of Class 3 suitability (Moderate % of provincial benchmark density) was on the Lassie Lake-Joan Lake plateau of about 1300-m elevation in the MSdm2 to the east of Arlington Hills and over to the Kettle Valley. All other areas were rated Low for suitability. The area east of Christina Lake was not extensively covered, and may contain some moderate moose winter range.

6 RECOMMENDATIONS The final moose winter range suitability map (Figure 5) shows the areas that should be included in moose winter management. Of particular note is the Lassie Lake- Joan Lake-Sandrift Lakes plateau. This area is only about 1300 m in elevation, and contains numerous wetlands and areas of moose winter range. More information is needed to accurately map the area east of Christina Lake, however, most of the winter moose range in this area overlaps with Mt. Faith- Gladstone Provincial Park, or with areas that would be managed as deer or elk range, and therefore is not of higher priority for management as moose winter range. LITERATURE CITED British Columbia Ministry of Environment, Lands and Parks British Columbia Wildlife Habitat Rating Standards Version 2.0. Prepared by Resources Inventory Branch, British Columbia Ministry of Environment, Lands and Parks for the Terrestrial Ecosystems Task Force, Resources Inventory Committee (RIC), Victoria, B.C. Gyug, L. W Moose Stratified Block Census, Management Units 8-5, 8-6 and 8-14, Okanagan Sub-region, February Report prepared for, Wildlife Branch, Ministry of Environment, Kamloops, B.C. Gyug, L.W. 2002a. Ungulate Aerial Surveys, Okanagan Region, March Report prepared for Ministry of Water, Land and Air Protection, Penticton, B.C. ( Gyug, L.W. 2002b. Moose, Elk, Mountain Goat, and Bighorn Sheep Winter Range Mapping, MWLAP Okanagan Region (8). Report prepared for Ministry of Water, Land and Air Protection, Penticton, B.C. Gyug, L.W Mule Deer Aerial Surveys, Okanagan Region, November-December Report prepared for Ministry of Water, Land and Air Protection, Penticton, B.C. Poole, K.G., D.A. Fear, G. Mowat and C.D. Shurgot Moose inventory in the Central Okanagan, January-February Report prepared for Ministry of Environment, Lands and Parks, Penticton, B.C. Simpson, K., Les W. Gyug, and J. Kelsall. Revised The effect of a new freeway on mule deer and moose. IN A Compendium of Wildlife Studies: Okanagan Connector Freeway 1987 to Highway Environment Branch, Min, of Transportation and Highways, Victoria, B.C.

7 - A ) o Kibmeters 0 BE1 Based Added in expert layer Excluded from final winter range 0 Figure 1. Broad Ecosystem Inventory -based moose winter range mapping compared to moose winter range management units proposed in fall 2002, Boundary Forest District, British Columbia.

8 Kibmeters A 2-3 Moose WR for Forest Management Fliaht Track Mar 2002 light Track Feb 2001 Figure 2. Aerial ungulate survey routes from February 2001 and March 2002, and previously known moose observations in Boundary Forest District, British Columbia.

9 - A - Flight Track Feb Kibrneters ( Moose WR for Forest Management Mule deer Dec Track Figure 3. Aerial ungulate survey routes on December 20,2002, and February 6,2003, Boundary Forest District, British Columbia.

10 - I=-. b A Moose Seen Feb 6,2003 A 1 A Kibmeters A >3 - Flight Dec 20 Track 2002 Dec Moose Sightings Flight Track Feb Moose WR for Forest Management Figure 4. Moose observations during aerial surveys, December 20,2002, and February 6,2003, Boundary Forest District, British Columbia.

11 Figure 5. Moose winter range suitability map for Boundary Forest District, 2003.

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