Pacific Water Shrew Salvage on SFPR Advanced Works July to September 2010

Transcription

1 Stantec 4370 Dominion Street, 5 th Floor Burnaby, BC V5G 4L7 Tel: (604) Fax: (604) VIA Ministry of Environment PO Box 9372 Stn Prov Govt Victoria, BC V8W 9M3 Reference: Pacific Water Shrew Salvage on SFPR Advanced Works July to September INTRODUCTION The Pacific Water Shrew (PWS) (Sorex bendirii), also known as the marsh shrew, is the largest shrew species found in British Columbia. The shrew averages 15 cm in length, of which half of that is its tail. The PWS has brownish black fur with a lighter belly. Its feet are brown in colour and have distinctive fringed hairs on the sides (Blood 1995). The PWS s range in British Columbia is limited to the Lower Fraser Valley as far east as Agassiz and north towards the Burrard Inlet (BC MWLAP 2004). The PWS has a long and linear home range, inhabiting riparian areas within 25 to 50 m of a slow-moving watercourse with forest coverage (BC MWLAP 2004). The PWS is semi-aquatic and its diet is distinguished by a high percentage of aquatic invertebrates. Pacific Water Shrews have been recognized as a species of conservation concern due to limited suitable habitat and rarity of occurrences in British Columbia. This species is red-listed in BC (BC CDC 2010) and is protected under the B.C. Wildlife Act. The PWS is designated as Endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) and receives federal protection under the Species at Risk Act (SARA). Where a species at risk has potential to be affected, the SARA requires a formal environmental assessment to be conducted before any works can proceed on or adjacent to potential habitat. Stantec retained EBB Environmental Consulting Inc. (EBB) to assist in a PWS salvage program at selected sites spanning Surrey to Delta, where culvert extensions and placements are being undertaken as part of the advanced site preparation activities for South Fraser Perimeter Road. The submission of this report, including capture records, satisfies the reporting requirements of the Ministry of Environment as outlined in Appendix A, Section 1 of Permit SU

2 Ministry of Environment Page 3 of 2 Reference: Pacific Water Shrew Salvage on SFPR Advanced Works July to September OBJECTIVE The Pacific Water Shrew (PSW) salvage was conducted to avoid direct impacts on PWS that could otherwise potentially result from advanced site preparation works (including culvert extensions, preload placement) in Surrey and Delta for the South Fraser Perimeter Road (SFPR). The objective was to prevent accidental mortality or injury to PWS and other wildlife, including other small mammals, amphibians and reptiles that are present in the immediate work areas. Impacts were minimized through the application of a salvage program developed in accordance with the Ministry of Environment s Draft Best Management Practices Guidelines (BMPG) for Pacific Water Shrew in Urban and Rural Areas (Craig et al. 2009). 3 STUDY AREA The general PWS salvage area was situated proximate to the Fraser River along 116 th Avenue and South Fraser Way spanning from Surrey to Delta. Seven sites were established near watercourses and adjacent riparian/upland areas previously identified in the South Fraser Perimeter Road Environmental Assessment. These sites were delineated as potential PWS habitat with moderate to high capability for the species. Figure 1 shows the location of two high-rated PWS sites (Cougar Creek, Bolivar Creek) and four sites with potential linkage/corridor habitat value (Manson Canal, Patullo Channel, Southward Creek, Landfill Creek). Maps for each site and coordinates for trapping locations can be found in Appendix A.

3 Ministry of Environment Page 4 of 2 Reference: Pacific Water Shrew Salvage on SFPR Advanced Works July to September 2010 Figure 1: South Fraser Perimeter Road study area and sites for PWS salvage program 4 METHODOLOGY Trapping methodology for PWS followed the recommended protocols outlined in the Best Management Practices Guidelines for Pacific Water Shrews in Urban and Rural Areas (Craig et al. 2009). The PWS salvage program commenced August 3, 2010 following completion of the installation of exclusion fencing at each location. Salvage activities were conducted at six sites and continued for eight days including eight over night sessions, for a total of 192 trap hours at each location. A combination of pitfall and Longworth traps were used and were checked every six hours, in accordance with the Best Management Practices Guidelines for Pacific Water Shrews in Urban and Rural Areas (Craig et al. 2009). In conditions of cold weather or heavy rainfall, trap captures are likely to experience higher levels of stress which may lead to mortality. In these circumstances, traps were temporarily closed and the trapping period for that location was extended until the 192 trap hours including eight trap nights, had been reached.

4 Ministry of Environment Page 5 of 2 Reference: Pacific Water Shrew Salvage on SFPR Advanced Works July to September 2010 Traps were placed every 15 m along the length of the excluded area, with pitfall traps being placed within 5 m of a watercourse and Longworth traps installed to survey adjacent upland areas. Pitfall traps were installed by burying a 6 L buck to sit flush with the ground. Traps were lined with shredded fiber bedding material to provide aid in thermoregulation and included a sponge to absorb moisture. Traps were baited using 10 g of moist cat food and were replaced every 24 hour period or as required. Lids were positioned using clothes pegs secured to the lip of the bucket to provide an entrance to the trap while protecting the bucket from precipitation. Drift fences were installed on either side of each pitfall trap as a guide to direct small mammals towards the opening of the trap. Drift fences were constructed using 1.5 m lengths of wood placed on either side of the trap and anchored by stakes. Longworth traps were placed in areas most likely to capture small mammals and included linear obstacles such as rocks and coarse woody debris as well as areas where runs were observed. Traps were lined with fiber bedding materials and baited with 10 g of cat food. Traps were cleaned and materials replaced every three days or as required for the duration of the survey. A description of the trap type and position for each site is described in Appendix A. 5 RESULTS Pacific water shrew salvage occurred at six sites with a total of 53 trap locations. Trapping efforts were carried out at all sites for eight consecutive 24-hour periods, as per the BMPG protocol. Each trap was therefore open for a total of 192 hours. Trapping effort resulted in the capture and relocation of one black rat (Rattus rattus), one deer mouse (Peromycus maniculatus), and three common shrews (Sorex cinereus). These individuals were not banded or tagged prior to release. Salvage captures did not include any Pacific water shrews or any other provincially or federally listed species at risk. Table 1 summarizes capture results. Detailed capture results are provided in Appendix B. Table 1: Summary of salvage results for the PWS salvage program for the South Fraser Perimeter Road, sites spanning Surrey to Delta. Common Name Scientific Name Capture Location Number Caught Black Rat Rattus rattus Landfill 01 1 Common Shrew Sorex cinereus Manson 01 1 Common Shrew Sorex cinereus Manson 03 1 Deer Mouse Peromyscus maniculatus Bolivar 01 1 Common Shrew Sorex cinereus Manson CLOSURE We trust this information meets your present requirements. Should you have any questions or require additional information, please contact the undersigned.

5

6 APPENDIX A Trap Locations

7 Stantec 4370 Dominion Street, 5 th Floor Burnaby, BC V5G 4L7 Tel: (604) Fax: (604) A 1: Positions of pitfall (PF) and Longworth (LW) small mammal traps at each trap location for South Fraser Perimeter Road advanced site preparation works from Surrey to Delta. Station Number Trap Type Zone Easting Northing Landfill Creek Landfill 01 LW Landfill 02 PF Landfill 03 LW Landfill 04 PF Landfill 05 LW Landfill 06 PF Landfill 07 LW Landfill 08 LW Landfill 09 PF Landfill 10 PF Southward Creek Southward 01 PF Southward 02 PF Southward 03 PF Southward 04 PF Southward 05 PF Southward 06 PF Southward 07 PF Southward 08 PF Bolivar Creek Bolivar 01 PF Bolivar 01 PF Bolivar 03 PF Bolivar 04 PF Bolivar 05 PF Bolivar 06 PF Bolivar 07 PF Bolivar 08 PF

8 Station Number Trap Type Zone Easting Northing Bolivar 09 PF Bolivar 10 PF Bolivar 11 PF Bolivar 12 PF Bolivar 13 PF Bolivar 14 PF Bolivar 15 PF Bolivar 16 PF Bolivar 17 PF Bolivar 18 PF Bolivar 19 PF Bolivar 20 PF Bolivar 21 PF Bolivar 22 PF Bolivar 23 PF Patullo Creek Patullo 01 PF Patullo 02 PF Patullo 03 PF Manson Creek Manson 01 PF Manson 02 PF Manson 03 PF Manson 04 PF Manson 05 PF Cougar Creek Cougar 01 PF Cougar 02 PF Cougar 03 PF Cougar 04 PF

9 Ministry of Environment Page 8 of 2 Reference: Pacific Water Shrew Salvage on SFPR Advanced Works July to September 2010 Figure 2: Cougar Creek Figure 3: Manson Canal

10 Ministry of Environment Page 9 of 2 Reference: Pacific Water Shrew Salvage on SFPR Advanced Works July to September 2010 Figure 4: Patullo Channel Figure 5: Bolivar Creek and Southward Creek

11 Ministry of Environment Page 10 of 2 Reference: Pacific Water Shrew Salvage on SFPR Advanced Works July to September 2010 Figure 6: Landfill Creek

12 APPENDIX B Capture Results

13 Stantec 4370 Dominion Street, 5 th Floor Burnaby, BC V5G 4L7 Tel: (604) Fax: (604) B1: Detailed summary of salvage results for the PWS salvage program for the South Fraser Perimeter Road, sites spanning Surrey to Delta. Record No. Date Time 1 6-Aug-10 06:12: Aug-10 11:30: Aug-10 11:35: Aug-10 12:45:00 5 N/Amortality 14-Aug :26:00 Station Number Landfill 01 Manson 01 Manson 03 Bolivar 01 Manson 03 Common Name Black Rat Common Shrew Common Shrew Deer Mouse Common Shrew Species Scientific Name Rattus rattus Sorex cinereus Sorex cinereus Peromyscus maniculatus Sorex cinereus Age Adult Adult Adult Adult Adult Sex Unknown Unknown Unknown Unknown Unknown Biometrics Body (incl. Tail tail) (mm) (mm) Hind Foot (mm) Weight (g) Relocation Site Bon Accord Creek N/Amortality Bolivar Creek Manson Creek