Linda Dupuis Box 663 Garibaldi Highlands, British Columbia Telephone: V0N 1T0 Cell:

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1 TECHNICAL MEMORANDUM Box 663 Garibaldi Highlands, British Columbia Telephone: V0N 1T0 Cell: TO: Metro Vancouver Policy and Planning Dept Kingsway, Burnaby, BC, V5H 4G8 Attention: Mr. John Worthen DATE: Sept 01, 2010 FROM:, M.Sc., R.P.Bio. JOB NO: RE: PACIFIC WATER SHREW SALVAGE ON BEAR ISLAND, LSCR: SUMMARY REPORT 1.0 INTRODUCTION Metro Vancouver s Watershed Management Division is proposing to establish a loop trail below (app. 250 m south of) the Seymour Dam. This trail will intercept two Seymour Reservoir and a small, ephemeral creek. Placing bridge spans over the comprises the bulk of construction works in the subject area, as it involves the establishment of riparian landing sites wide enough to accommodate the large machinery needed to build bridge abutments and carry two 38 m metal spans into place. Works in the remainder of the site will involve clearing and grubbing the trail area. The Pacific water (Sorex bendirii) is considered threatened provincially (red-listed; BC Conservation Data Centre 2006) and federally (Part 3 of Schedule 1 in the Species at Risk Act; Environment Canada 2006). This species was reported four kilometres south of Seymour Lake in 1991 (c.f. Diamon Head Consulting Ltd. 2010). Given the proximity of the Pacific water record to the proposed trail site, and the fact that most of the subject area is comprised of marginal habitat for this species (Dupuis 2010a), a Pacific water salvage was undertaken in the area as recommended in the provincial Best Management Practices (BMP) for this species (refer to Craig et al. 2009). This memo summarizes the results of the salvage, which took place bewteen August 19 th and 29 th, 2010.

2 Mr. John Worthen METHODS Below is a summary of the Pacific waters salvage methods, which are described in greater detail in the salvage plan submitted to the Ministry of Environment in July 2010 (Dupuis 2010b). Silt fences were established in the subject area to exclude the construction site (60 m on either side of the two Seymour Reservoir ) from the remainder of the forest. A total of 31 6L buckets (22 cm deep) were used to intensively sample the subject area. Pitfall traps were buried flush with the ground at 15 m intervals along the exclusion fences or natural runways (linear terrain features, and logs). Traps were equipped with wood chips and sponges, and sheltered by cover boards to minimize the risk of hypothermia from cold and/or wet conditions. Mealworms were regularly supplied to ward off starvation. Traps were checked at six-hour intervals for eight days, between August 19 th and 29 th, Captured animals were identified, weighed, and measured prior to being released in the same vicinity, beyond the exclusion fences. Captured animals were marked with a felt pen, to gage the effectiveness of the exclusion fences. 3.0 RESULTS 3.1 General Findings The traps were checked 24 times during late August. More specifically traps were checked at 6: 00 am, 12: 00 pm, 6:00 pm, and 12:00 am from August 19 th to Aug 23 rd and from August 27 th to 29 th. Traps were sealed between salvaging sessions (from August 24 th to 26 th ). Ten animals were captured in the traps during the salvage period, including seven common s (Sorex cinereus), two ensatina salamanders (Ensatina eschscholtzii), and one Pacific water (Table 1). Five of seven (71%) of the common s that were encountered carried ticks. One of the common s was found dead in the trap despite the warm, dry conditions and the sypply of mealworms. Captures were equally distributed: (1) between Bear Island, the east and west sides of the ouflow channels (Table 1); and (2) within the riparian zones (0 to 60 m from the shoreline).

3 Mr. John Worthen Table 1. Summary of Pacific water salvage below Seymour Dam in August, 2010 Species Date Site Total length (cm) Weight (g) Age Comments Aug 19 6:00AM 60 m west of Juv. Escapee; four ticks Ensatina Aug 19 6:00AM 60 m east of Yrlg. Released in construction site Aug 19 12:00AM Bear Island (between channels) Adult Three ticks Aug 20 12:00PM < 5 m west of Adult One tick Aug 20 12:00AM 60 m east of channels Juv. Aug 23 6:00AM Bear Island Adult Dead in trap Pacific water Aug 27 3:00AM (late midnight shift) 60 m west of E, N Juv. Not marked Aug 28 3:00AM 15 m east of Adult Three ticks Ensatina Aug 28 6:00AM Bear Island Adult Aug 29 12:00AM 15 m east of Adult Two ticks

4 Mr. John Worthen Live captures were released up to 50 m beyond the exclusion fences. 3.2 Pacific water sighting The Pacific water was captured in the early morning on August 27, 2010 (day 6 of salvage), below the Seymour Dam (Figure 1). The individual was 14.6 cm in total length and weighed 10 g suggesting that is was a juvenile (photos in Appendix 1). Figure 1. Site of the Pacific water capture in relation to Seymour Dam The young Pacific water was located 60 m west of the Seymour Reservoir outflow channels (UTM: E, N). The banks of these channels are high (>1 m) and steep (Dupuis 2010a), and thus not generally accessible to water s. No other sources of water were found within 100 m of the trap in which this animal was captured (Figure 1). The surrounding forest is dominated by red alder (Alnus rubra), with minor components of western hemlock (Tsuga heterophylla), western redcedar (Thuja plicata), Amabilis fir (Abies amabilis) and Douglas-fir (Pseudotsuga menziesii). The stand is dense ( stems/ha), with little understory or ground cover. The soil has a moist nutrient regime, and a moderate to high level of nutrients (Diamond Head Consulting Ltd. 2010). There is very little coarse woody debris on the forest floor (Dupuis 2010a).

5 Mr. John Worthen CONCLUDING REMARKS The eight-day salvage successfully removed small vertebrates, including a Pacific water, from the area around the Seymour Reservoir where bridges are to be established, and banks armoured. A small, ephemeral creek known as Smokey Creek is located roughly 150 m east of the Seymour Reservoir outflow creeks. This creek has gentle banks, and a moderate cover of ferns and wood. It is possible that the Pacific water juvenile caught on the west side of the overflow channels originated from the Smokey Creek subdrainage. To err on the side of caution, any clearing and grubbing within 60 m of Smokey Creek should be minimized (trail should be narrow). A wooden bridge should be established over the ephemeral channel to maintain shoreline continuity for Pacific water s, and to minimize bank erosion and channel disturbance from foot traffic. 5.0 CLOSURE A permit was obtained from the Ministry of Environment for this salvage (No. SU ) and the trapping was conducted in accordance with permit terms. It is the understanding of the undersigned that SHIM mapping has already been done by Metro Vancouver for the Seymour watershed, which includes the area in and around the salvage site (the 500 m radius required by the Wildlife permit). Please feel free to contact the undersigned at (604) or should you have any questions or comments regarding the Bear Island Bridges salvage. Sincerely,, M.Sc., R.P.Bio. Wildlife Habitat Ecologist

6 Mr. John Worthen REFERENCES B.C. Conservation Data Centre Species Summary: Sorex bendirii. B.C. Ministry. of Environment. Available: (accessed Sep 8, 2006). Craig, V.J., R.G. Vennesland, and K.E. Welstead Best Management Practices Guidelines for Pacific Water Shrew in Urban and Rural Areas. Working Draft report to Ecosystem Standards and Planning, Biodiversity Branch, Ministry of Environment, Surrey, BC. Diamond Head Consulting Ltd LSCR Trail Impact Overview Assessment. Report to Metro Vancouver, prepared on January 5, Vancouver, BC. Dupuis, L. 2010a. Pacific water mitigation. Site (Reconnnaissance) meeting summary. Letter-memo submitted to Metro Vancouver on July 14, Vancouver, BC. Dupuis, L. 2010b. Pacific water salvage plan Bear Island bridges in the Lower Seymour Conservation Reserve. Memo submitted to Metro Vancouver on July 23, Vancouver, BC. Environment Canada Species at Risk Pacific water (Sorex bendirii)

7 Mr. John Worthen Appendix 1: Photos of the captured Pacific water

8 Photo 1. Pacific water in trap (TL = 146 mm) Photo 2. Uniform body colour and hair fringe on hind feet