Hebb described the characteristics of valuable wildlife trees in Coastal BC as laid out by the Wildlife Tree Committee in 2012: a minimum dbh of 70cm, a minimum height of 15m, visible signs of decay “such as broken tops, cavities and hollow areas,” and a decay stage of 2-6 (2013, p. 17). See Table 7 for uses of wildlife trees by bird species. The wildlife trees of Bowker Creek were analyzed against these standards: “Based on these measures, the woods at Bowker Creek West support some highly valuable wildlife trees. The majority of wildlife trees that were identified, 50 of the 77, were 15m in height or greater. In terms of dbh, the trees may have somewhat less value to wildlife as only 25 of the them were 70cm dbh or greater, and some of these were multi-stemmed trees. Nevertheless, trees as small as 20cm dbh had evidence of wildlife use and cavity excavation, and the trees from 35cm-69cm dbh also showed a great deal of usage. Most of the trees that were identified in the survey were in stages 2-6 of decay (based on visual appearance) which is good for wildlife. The high number of trees in stage 2 indicate that there will be ample recruitment into later stages in the next decades” (Hebb 2013, p. 17). Table 7. Birds been sighted at UVic that are known to use wildlife trees (Adapted from Harrop-Archibald 2007) Bird Species Wildlife Tree Use Great Blue Heron Open nest on large tree limbs Hooded Merganser Secondary cavity nester Turkey vulture Roosting Bald Eagle Open nest on large tree limbs, hunting perch, roost Red Tailed Hawk Hunting perch Merlin Secondary cavity nester Great Horned Owl Secondary cavity nester, nest in broken tree top, hunting perch Barred Owl Secondary cavity nester, nest in broken tree top, winter roost Western Screech Owl Secondary cavity nester Vaux’s Swift Secondary cavity nester, winter roost Belted Kingfisher Hunting perch Red Breasted Sapsucker Primary cavity nester, roost, foraging Northern licker Primary cavity nester, roost, foraging Pileated Woodpecker Primary cavity nester, roost, foraging Downy Woodpecker Primary cavity nester, roost, foraging Hairy Woodpecker Primary cavity nester, roost, foraging Pacific Slope Flycatcher Secondary cavity nester, hawking perch Violet Green Swallow Secondary cavity nester Tree Swallow Secondary cavity nester Chestnut Backed Primary cavity nester (opportunistic secondary cavity nester), foraging, Chickadee winter roost Red Breasted Nuthatch Primary cavity nester, occasional secondary cavity nester, foraging, winter roost 69 Brown Creeper Secondary cavity nester, foraging Bewick's Wren Secondary cavity nester There are several invasive plant species of concern present in the Bowker Creek ecosystems. The dominant invasive species is English ivy, found climbing vertically up trees (Figure 63 and Figure 64Error! Reference source not found.) with the highest occurrence in the south of Bowker Creek (Kathrens & Jennings 2016). Additional species that are a high priority to remove are yellow flag iris, thistle, Daphne, Robert’s geranium, grasses and English holly (Kathrens & Jennings 2016). Distribution of invasive plants varies by species: “Large patches of English holly are found throughout, large stands of Himalayan blackberry are found bordering most of the area, and a high number of mature English hawthorn trees can be found in the southern portion of Bowker Creek West” (Kathrens & Jennings 2016, p. 62). See Figure 65 for a map of the distribution of invasive species in Bowker Creek. Figure 63. Thick stems of ivy climbing a tree (Photo: Kathrens & Jennings 2016) Figure 64. Tree trunks completely engulfed in climbing ivy (right) (Photo: Kathrens & Jennings 2016) 70 Figure 65. Distribution of Invasive Species in Bowker Creek (Source: Kathrens & Jennings) 71 History and Restoration The original plans for the campus from the 1960s did not preserve Bowker Creek as a natural area on campus; it was slated for “academic expansion and graduate studies” (Hocking 2000, p. 13). Shortly before the next campus plan was published in 2003, in 2001 UVic became a stakeholder in the multi- stakeholder group, the Bowker Creek Initiative (UVic 2006 & Kathrens & Jennings 2016). UVic contributed to the development of the January 2003 Bowker Creek Watershed Management Plan, which stated its vision for the watershed a follows: “The varied human uses and natural areas in the Bowker Creek Watershed are managed to minimize runoff pollution making Bowker Creek a healthy stream that supports habitat for native vegetation and wildlife, and to provide a community greenway that connect neighbourhoods” (Westland Resource Group 2003, p. i). The four goals outlined in the plan were (p. ii): • Individuals, community and special interest groups, institutions, governments, and businesses take responsibility for actions that affect the watershed • Manage flows effectively • Improve and expand public areas, natural areas, and biodiversity in the watershed • Achieve and maintain acceptable water quality in the watershed In the Campus Plan 2003, protection was given to Bowker Creek that was equivalent to all other natural areas on campus outside of Ring Road: a ten-year moratorium on development (UVic 2003). The importance of Bowker Creek to the campus with further elucidated in the 2004 Integrated Stormwater Management Plan (Lloyd). Bowker Creek, with Mitchell’s Moat and its surrounding riparian and wetland ecosystems was described as “the most naturally protected system at the University because the water is extensively filtered through surface ponds and natural bio-treatment areas” (Lloyd 2004, p. 129). In the Sustainability Report 2006, it described how UVIC had been participating for the past five years in the Bowker Creek Initiative (Robson, Corbett & Webb 2006). The involvement was further described: “From creek clean up projects to riparian area restoration, university staff have played an active role in the revitalization of this urban watershed” (Robson et al. 2006, p. 4). While this sounds as though these restoration activities were carried out on the campus itself, this was not specified in any detail. As a further project of the Bowker Creek Initiative, the Bowker Creek Blueprint was published in 2012 that defined a 100-year management plan for the watershed based on the goals and vision of the Watershed Management Plan. The Blueprint laid out recommendations for management and restoration of each reach of the stream, including for reach 15 on the UVic campus. Facilities Management was identified as the lead agency in charge of the implementation of these recommendations, which included: invasive species removal, installation of interpretive signs, a widening of riparian buffers (the vegetation on either side of the stream), and native species planting, with willow staking around Mitchell’s Moat. Student projects were also identified as a source of support for carrying out these recommendations. Perhaps the most ambitious goal, “to obtain perpetual protection of the reach beyond 2011,” would require the cooperation of many more elements of UVic to achieve. A map published in this report identified areas all along the creek where restoration activities have taken place, and this includes the UVic campus although further details of this restoration were not provided. See Figure 66 for details of this map for the headwater of Bowker Creek on the UVic campus. 72 Figure 66. The headwaters of Bowkers Creek on the UVic campus. The pink highlight indicated creek restoration areas (Adapted from the Bowker Creek Initiative 2012). 73 The UVic Campus Plan 2016 contains several references to Bowker Creek. It is designated as a protected natural area to be preserved and restored as part of the campus’ green ring, however it is not given protection in perpetuity as requested in the Blueprint. It said to implement “wherever possible” the management and restoration recommendations in the Watershed Management plan and the Blueprint (UVic 2016, p. 44). Equally broadly, it contained a policy regarding creek corridors and waterbodies, which was to preserve and restore those that are located in natural areas (UVic 2016, p. 56). More specifically, it recommended that UVic consider replacing lawn at McGill Road entrance to the university “with meadow and forested landscapes to create improved habitat and rainwater infiltration around the sensitive Bowker Creek ecosystem” (UVic 2016, p. 54). An early restoration activity, predating 2008 but possibly installed significantly earlier, are two log weirs located near the University Club, just downstream of Mitchell’s Moat. Weirs span the width of the stream and create a drop in the channel depth, while reducing erosion and catching sediment. See Figure 67 for location of the weirs. See Figure 68 and Figure 69 for photos of the weirs. Figure 67. Black lines indicate location of existing weirs. Yellow lines represent weirs proposed as part of a student project (Source: Dasanjh et al. 2009) 74 Figure 68. Southern log weir (Source: Dasanjh et al. 2009) Figure 69. Northern log weir (Source: Dasanjh 2009) 75 Invasive species work parties commenced in 2016 as part of the Public Engagement portion of the Invasive Species Management Strategy (Kathrens & Jennings 2016). The first event, an ivy pull, was hosted in October by Kathrens and Jennings with the Ecological Restoration Volunteer Network (ERVN). Five volunteers were present, mostly geography and environmental studies students (Kathrens & Jennings 2016). See Figure 70 and Figure 71 for photos from the event. Figure 70. Volunteers removing ivy stems from a tree trunk in Bowker Creek (Source: Kathrens & Jennings 2016) Figure 71. Volunteers display the thick ivy stems removed from Bowker Creek (Source: Kathrens & Jennings 2016) 76 Additional events have since been hosted by the ERVN, including in December of 2017 and January 2018, and two events in February 2018. The focus of the February events was clipping vertical growing ivy from trees and removing mats of ivy from the ground near the Alumni Chip Trail (“February Restoration” 2018). References Bokor, C., Brett, E., Brennan, J., Gryzbowski, N.