Conservation Priorities in the Squamish River Estuary To: Squamish Estuary Conservation Society

3.2 Maintain Good Water Quality

Estuaries are efficient filters of particle-reactive chemical contaminants (PAHs, halogenated hydrocarbons, heavy metals), which mainly enter estuaries via land run-off, river inflow, and atmospheric deposition. Tight restrictions on waste dumping, waste water discharge, and log handling can reduce contaminant concentrations. It would be wise to get some baseline data on water quality before any further development along Mamquam Channel and East Channel, and to gather data at sewage and stormwater release sites as well. The Ministry of Water, Land and Air Protection (contact: Brent Moore) has water quality data for some areas within the estuary, but potential gaps in information could be identified. A thorough dataset would serve as a guide for future actions and management needs.

Dredging at the mouth of the Blind Channel is required periodically. The process of dredging stirs up bottom sediments and re-releases toxins from the chemical plant, log sorts, saw and pulp mills, and hogfuel storage site, into the water column. Ideally the spoils would be removed by clamshell dredging or be suctioned out by centrifugal action, but the latter process can be costly. Alternatively, dredging should be done at low tide and the toxic spoils should be disposed of in upslope habitats away from watercourses, wetlands, unclassified channels, and seepages. Stabilization and recolonization of dredged areas occurs within a year or more (Kennish 2002).
Water quality problems, substrate compaction and siltation, and the potential for damaging benthic organisms can be minimized at the log handling facilities by using upland sorts as much as possible, bundling logs to increase rafting capacity, minimizing rafting area, and locating rafts where there is good water circulation, with enough depth to float log bundles during all tidal regimes and prevent disturbance of substrate by tugs (Kennish 2002). To prevent debris from entering the water and minimize toxins from leaching during storage, logs should be bundled in a way that reduces log bumping and bark loss, easy let-down devices should be used to dump logs, duration of log storage should be kept to a minimum (less than seven days), and bark and debris from the unloading area should be disposed of, away from the estuary (Brown 1975).
Following the transfer of the West Barr log sort to the Mamquam Blind Channel, the central portion of the estuary should receive a low level of development. Road and parking surfaces should be prohibited because exposed surfaces, especially impervious or toxic ones, increase the input of pollutants to the water, through storm run-off and spills. In addition, direct disturbance and noise pollution at the centre of a wetland decreases its value as a wildlife refuge.
Refueling areas should be prohibited near the water on East and Mamquam Deltas, particularly where tree buffers are absent and surfaces are paved. Herbicide and pesticide use should be prohibited in the downtown area and along the train tracks, particularly within 50 m of any water body. In essence, the use of chemicals, roads, parking lots and large open work surfaces should be minimized to reduce run-off, and the possibility of fuel leaks and accidental spills. Efforts should be made to prevent motorized activity in Central Channel (e.g., phase out use of the dock on the west side of the Terminals). This will reduce the chance for contamination, fuel spills, and direct disturbance to fish and wildlife, and eliminate the need to maintain a dredge pocket in Central Channel.
Wetlands are important water storage sites, a source of drinking water for all small and large wildlife, and a breeding site for wetland specialists. Draining, contaminating and filling permanent wetlands in and along the margins of the estuary should be prevented. This includes the swamp in Rose Tatlow Park, at the head of the Mamquam Blind Channel.

3.3 Manage Recreation and Tourism

The mudflats and saltmarshes are the most productive element of the estuary, and because they are ultimately the source of food for all fish and most wildlife living or visiting the estuary, they should receive high protection priority. There should be no additional trails along the training dyke, and any changes to existing trails should minimize overlap with natural edges such as the shoreline and riparian zones. Loops such as Meadow Loop and Forest Loop, Woodpecker Trail and Restored Marsh Loop, are an effective way of directing pedestrian traffic in and out of precious ecosystems, and minimizing the tendency for random exploration. Easy access should be provided from the downtown area to trails on East Delta, where the integration of wildlife and recreation is recommended. Conversely, Central Delta represents a wilderness priority zone and trails along the Training Dyke should be minimal, and require some effort on the part of visitors.

A boardwalk should be constructed along the western and southern dykes of Meadow Loop, and on the southern dyke of the Forest Loop, to prevent further soil erosion and subsequent loss of the trees that screen pedestrians from Central Channel, East Marsh and North Field. Meadow Loop is ideally situated to give visitors an exceptional look at the estuary’s beauty and a vantage of the surrounding crown of mountains. Aesthetic experiences give people the incentive to protect special habitats when these become threatened.
Meadow Loop is well screened from Central Channel and East Marsh, two of the most productive parts of the estuary. Some users have recommended that a trail be established through Bridge Pond, along an existing old dyke, to complete the Meadow Loop and keep pedestrians off the rail line. Bridge Pond has the highest bird biodiversity (127 species) in the estuary because of the inherent edges created by the diversity of habitats and intercepting channels. A trail section through Bridge Pond is not likely to displace wildlife because it is well away from the mudflats used by shorebirds, dabblers and other flighty birds, and the structural diversity that attracts non-water birds and small mammals would not be altered. Indeed, a trail through Bridge Pond could help deter incompatible land uses in Bridge Pond (i.e., urban, commercial and industrial development) and protect the forest buffer that separates the estuary from the town centre.
A few changes to Forest Loop are recommended to direct visitors through the estuary efficiently. The trail would best be accessed from the periphery, via a bridge across Cattermole Slough at the end of Winnipeg St. For a trail system to be least invasive to wildlife it should be simple and its location along inherent edges should be minimized. There are currently three hiking choices at this location: an inner forest loop, the road to the log sort, and swan trail. Site A has a high diversity of passerine birds, raptors, and woodpecker species, many of which favour more interior forest conditions. It might be wise to phase out one of these pathways. Ideally, the road should be phased out once the log sort is gone, and all road fill should be removed. Motorized vehicles are very invasive to wildlife, and they facilitate the accumulation of debris (garbage disposal, party sites) and the introduction of pollutants to the water. If the road is rehabilitated and access is prohibited, it could be incorporated into Forest Loop as a trail and the interior loop could be phased out to minimize habitat fragmentation. In order to stay away from inherent edges, the section of trail along upper Cattermole Slough should also be phased out. It would be better to have a bridge directing pedestrians across the slough to the short trail linking Site A to the dyke along the western edge of town, east of the railway line. That trail layout minimizes hiker traffic within the estuary without preventing people from making use of the area, and seeing the attractive meadows and bordering mature riparian forest. The north dyke section of Forest Loop could lead to within 50 m of the water (northwest corner of existing log sort) to give visitors a view of Central Channel. An efficient loop or set of loops will not displace forest dwellers if fragmentation is kept to a minimum.
According to the land use gradient proposed above, Central Delta should be a wildlife priority zone, with low levels of recreation. Current trails along the training dyke have a low impact on wildlife because they are loops, and they are clear of natural edges (particularly the mudflats and shoreline). If human use patterns stay as they are, signage along the restored marsh trail loop and at the end of the training dyke would help to make visitors cognizant of their influence on ecosystems and their inhabitants. In particular, garbage disposal should be encouraged and facilitated. If the windsurfer put-in could be relocated to the northwest corner of the Terminals site, motorized traffic on the training dyke could be prohibited. Pedestrian traffic along the restored marsh and woodpecker loops would thus be limited to cyclists, and keen hikers and naturalists. Motorized access to the mouth of the Squamish River would be prevented, more effectively protecting the heart of the Wildlife Management Area from disturbance. The movement of mammals and other wildlife into the estuary from the contributing watershed would not be interfered with. Refraining from mowing the road shoulders and using herbicides and pesticides would minimize the impact of the dyke on wildlife. The windsurfers would be within the moderate recreation zone, and their presence at the Terminals site would have minimal impact on wildlife if: (1) activities were restricted to the summer months (June to September); (2) the put-in was 100 m from East Marsh boundary; and (3) other public use was prohibited. East Channel has relatively low wildlife value and could have unrestricted use by hikers and cyclists, or for urban, commercial and light industrial development as long as water quality is maintained.
If a cable crossing is established across the river at Fisherman’s entrance (see Baumann 1998), trails along the western shore to the estuarine flats of Squamish River should be prevented. Any trail above the western deltaic environment should be situated away from the riparian edge as well, preferably in the upper powerline corridor.
An impact assessment should be done before permitting the use of non-motorized watercraft in the estuary channels and at the mouth of Squamish River. Kayak and canoe traffic is likely to have a low impact if: (1) the use of channels is restricted to the summer period (June to mid September) when wildlife use is at a minimum; (2) access to East of Fill and East Marsh is prohibited to prevent substrate disturbance; and (3) a limited number of boats are allowed on the water per season (based on an impact assessment). Access to the western shore of Squamish River should be restricted to Fisherman’s entrance because this is a popular access point for Echo and Alec Lakes, and the crossing is nearly one kilometer from the most northern mudflat at the mouth of the river. A popular put-in for boats on East Delta, is the parking lot in the bend of Crescent Slough. This put-in is suitable given that the site is already disturbed (lacks a riparian zone).

3.4 Enhance Natural Habitats

The Squamish River Watershed Society and Matt Foy (via Department of Fisheries and Oceans funding from the SEMP Compensation Agreement) have successfully restored and enhanced the dredge spoil site to the east of the training dyke, by restoring the filled marsh to intertidal elevations, establishing small tidal fish-rearing and spawning channels, and replanting the area with native vegetation. There is a need, however, to encourage the establishment of more gradual slopes (e.g., 3:1 and 4:1 horizontal to vertical ratio) in these enhancement project areas to increase the use of excavated channels by other organisms, namely water birds. Furthermore, remaining meadow habitat is scarce in the Georgia Basin. Habitat restoration such as channel construction must be done in such a way as to minimize the impact on meadowlands. In particular, channel excavation materials should be removed or distributed such that mudflat and seagrass elevations are maintained. In addition, the introduction of small trees and shrubs should be limited to the terrestrial edges of the estuary to prevent humans from acceleration the rate of succession in the estuary.

Removing all fill materials should rehabilitate the log sort that is being phased out of the centre of the estuary. The site should be restored to its subtidal and intertidal surface, to create more mudflat and saltmarsh habitat. The slope at the waterline should be 3:1 or 4:1 to accommodate dabblers and shorebirds. Any future channel excavations should also aim for a more gradual slope, to make these channels useful to wildlife as well.
Edith Tobe has encouraged several levels of government to develop large eel grass beds on the margins of Central Channel, and at the mouth of Mamquam Blind Channel.

3.5 Education

The importance of education cannot be emphasized enough. Signage would be a worthwhile investment to ensure proper long-term land stewardship, on the part of all citizens. Meadow and Forest Loops are an ideal place to raise awareness about ecosystem elements, functions, and health. If an interpretive centre is ever proposed, it should be situated at the periphery of the estuary, beyond the riparian forest buffer or in an existing disturbed site such as the old sewage treatment plant, once it is phased out.

4.0 Conclusion

Estuaries are unique ecosystems because they represent an interface of terrestrial, freshwater and marine habitats. Between 1986 and 2001, commercial and public use of estuaries has increased from 600 to 1375 ha (2.1 to 4.7 %) in British Columbia. Primary users in 2001 were log storage and handling (604 of 29,000 analyzed hectares of estuary) but area management for conservation has increased from 23% (of 6700 ha) to 69% (20,300 ha). Most of this protection is accounted for by conservation efforts in the Fraser River estuary (Jeo et al. 2003).

In this report, the ecological value of the estuary has been detailed, and the fragility of some of its elements has been outlined. In summary, fish are an extreme conservation concern, and one third of BC fish are red listed in BC. The reduction in northwest salmonid runs appears to be at least partly related to poor marine (estuary and ocean) survival (Emmet et al. 2000). Fish are an integral part of culture, heritage and economy. Sea-going species bring marine-derived nutrients to forest and stream ecosystems, which benefit many species.
The avifauna is rarely considered when impacts of disturbance to estuaries are being assessed, yet thousands of birds use estuaries at some point in their life history. Staging areas are critical for water birds that travel long distances, to rest and replenish fat reserves so they can continue on with their flight. Some species must migrate several thousands of kilometres in an ever more fragmented landscape, to reach their summer and winter grounds. Migration is a leap of blind faith, and many individuals don’t make it to their destination due to storms, lack of fitness, a faulty internal compass, predation, or inexperience. Migration depends upon links, such as safe havens, food and clean water, strung out in due measure and regular occurrence along routes that may cross thousands of miles (Weidensaul 2000). Availability of estuaries is the difference between life and death for many species of estuarine users.
Urban sprawl, industrial development and increasing recreational pressure decrease the availability of estuary havens enormously. Sustained disturbance associated with footpaths, roads and railroads reduce local habitat quality for waterbirds in particular, and the carrying capacity of estuaries (Burton et al. 2002). The evidence is that human occupancy of coastal areas will continue to increase during the 21^st century. This can be counter-balanced with nature-based tourism and recreation that aims to educate people and maintain ecosystem integrity. Having identified the estuary’s needs for long-term survival, a partnership must be built. With community support it is possible to prevent fragmentation, isolation and functional degradation by coordinating the development in and adjacent to the estuary with a landscape-level environmental perspective. Through planning and understanding the form and function of estuaries, a visionary community can successfully protect crucial habitat, aiding the survival of plant and animal communities while expanding its economy.

5.0 Literature Cited

Baumann Engineering. 1998. Squamish River Pedestrian Crossing Study. Project for Forest Renewal B.C. and the District of Squamish. Squamish, B.C.

Baur, A. and B. Baur. 1992. Effect of corridor width on animal dispersal: a simulation study. Global Ecology and Biogeography Letters 2: 52-56.
BC Ministry of Forests and BC Ministry of Environment. 1995a. Riparian Management Guidebook. Joint publication, Victoria, BC.
BC Ministry of Forests and BC Ministry of Environment. 1995b. Forest Road Engineering Guidebook. Joint publication, Victoria, BC.
British Columbia Nearshore Habitat Loss Work Group. 2001. A strategy to prevent coastal habitat loss and degradation in the Georgia Basin. Dept. of Fisheries and Oceans, in conjunction with Ducks Unlimited, Environment Canada, BC Land Use Coordination Office, BC Ministries of Agriculture, Environment, and Municipal Affairs, and West Coast Environmental Law, Vancouver, B.C.
Brosofske, K.D., Chen, J. Naiman, R.J. and J.F.Franklin. 1997. Harvesting Effects on Microclimatic Gradients from Small Streams to Uplands in Western Washington. Ecological Applicattions 7(4): 1188-1200.
Brown, R. (Ed.). 1985. Management of Wildlife and Fish Habitats in Forests of Western Oregon and Washington. USDI Bureau of Land Management and USDA Forest Service. Pacific Northwest Region, OR. R6-F&WL – 192-1985.
Bunnell, F.L. and L.A. Dupuis. 1994. Riparian habitats in British Columbia; their nature and role. In (K.H. Morgan and M.A. Lashmar, Eds.) Riparian Habitat Management and Research. Proceedings of a workshop held in Kamloops, B.C. 4-5 May, 1993. Special Publication of the Fraser River Action Plan, Environment Canada, and the Canadian Wildlife Service. Delta, B.C.
Burton, N., Armitage, M., Musgrove, A. and M. Rehfisch. 2002. Environmental Assessment: Impacts of man-made landscape features on numbers of estuarine waterbirds at low tide. Environmental Management 30(6): 857-864.
Cannings, Dick. 1980. Bird Censuses on the Squamish River estuary, January to March 1980. Report to D. Trethewey. Canadian Wildlife Service, Delta, B.C.
Campbell, W. 1972. The green heron in British Columbia. Syesis 5: 235-247.

Campbell, W., Dawe, N., McTaggart-Cowan, I., Cooper, J., Kaiser, G. and M. McNall. 19990. The Birds of British Columbia. Vol. 1. Nonpasserines. Royal British Columbia Museum, Victoria.

Chilibeck, B., Chislett, G. and G. Norris (Eds.). 1993. Land Development Guidelines for the Protection of Aquatic Habitat. Department of Fisheries and Oceans, in collaboration with B.C. Ministry of Environment. Vancouver, B.C.
Cooperrider, A.Y., Boyd, R.J. and H.R. Stuart, S.L. (Editors). 1986. Inventory and Monitoring of Wildlife Habitat. US Dept. of Interior, Bureau of Land Management, Service Center, Denver, CO. 858 pp.
Dupuis. L., Smith, J.N.M. and F. Bunnell. 1995. Relation of terrestrial-breeding amphibian abundance to tree-stand age. Conservation Biology 9(3): 645-653.
Emmett, R., Llanso, R, Newton, J. Thom, R., Hornberger, M., Morgan, C., Levings, C., Copping, A. and P. Fishman. 2000. Geographic Signatures of North American West Coast Estuaries. Estuaries 23(6): 765-792.
Estuary Working Group. 1974. The Squamish River Estuary. Status of Environmental Knowledge to 1974. Special Estuary Series No. 2, Environment Canada.
Gaumer, T.F., Benson, S.L., Brewer, L.W., Osis, L., Skeesick, D.G., Starr, R.M., and J.F. Watson. 1985. Estuaries. Chapter 5 in Brown, E.R. Ed.) Management of Wildlife and Fish Habitats in Forests of Western Oregon and Washington. USDA Forest Service, Pacific Northwest Region, in cooperation with USDI Bureau of Land Management. Portland, OR.
Hutchinson, I. 1988. The biogeography of the coastal wetlands of the Puget Trough: deltaic form, environment, and marsh community structure. Journal of biogeography 15: 729-745.
Jeo, R., Sanjayan, M. and D. Sizemore. 2003. BC Central Coast Conservation Area Design. www.rainforest.org.
Johnston, B. and L. Frid. 2002. Clearcut logging restricts the movements of terrestrial Pacific giant salamanders (Dicamptodon tenebrosus Good). Can. J. Zool. 80:2170-2177.
Kennish, M.J. 2002. Environmental Threats and environmental future of estuaries. Environmental Conservation 29(1): 78-107.
Lambeck, R.J. 1997. Focal species: a multi-species umbrella for nature conservation. Conservation Biology 11(4): 849-856.
Logan, W., Brown, E.R., Longrie, D., Herb, G. and R.A. Corthell. 1985. Edges. Chapter 6 in Brown, E.R. Ed.) Management of Wildlife and Fish Habitats in Forests of Western Oregon and Washington. USDA Forest Service, Pacific Northwest Region, in cooperation with USDI Bureau of Land Management. Portland, OR.
Mahaffy, M., Nysewander, D., Vermeer, K., Whal, T. and P. Whitehead. 1994. Status, Trends and Potential Threats Related to Birds in the Strait of Georgia, Puget Sound and Juan de Fuca Strait. Symposium on the Marine Environment organized by the Canadian Wildlife Service, British Columbia, and the U.S. fish and Wildlife Service, Washington.
Meidinger, D. and J. Pojar (Eds.). 1001. Ecosystems of British Columbia. Special Report Series No. 6. BC Ministry of Forests, Victoria, B.C.
Merriam, G. and A. Lanoue. 1990. Corridor use by small mammals: field measurements for three experimental types of Peromyscus Leucippus. Landscape Ecology 4(2/3): 123-131.
Naiman, R.J. and K.H. Rogers. 1997. Large animals and system-level characteristics in river corridors; implications for river management. Bioscience 47(8): 521-529.
Rosenberg, D.K. 1998. Compensatory behavior of Ensatina eschscholtzii in biological corridors: a field experiment. Can. J. of Zool 76(1): 117-133.
Spackman, S.C. and J.W. Hughes. 1995. Assessment of minimums stream corridor width for biological conservation: species richness and distribution along mid-order streams in Vermont, USA. Biological Conservation 71: 325-332.
Squamish Estuary Coordinating Committee. 1999. Squamish Estuary Management Plan 1999. District of Squamish in collaboration with BC Environment, BC Lands, BC Rail, the Department of Fisheries and Oceans, Environment Canada and BC Business, Culture and Tourism. Squamish, B.C.
Trethewey, D.E.C. 1985. Bird Use of the Squamish River Estuary. Canadian Wildlife Service, Delta, B.C.
Weidensaul. S. 2000. Living on the Wind; Across the hemisphere with migratory birds. North Point Press, New York, NY.
www.wa.gov/Publications/pshealth2002/habitat_eelgrass.htm. 2003. Eelgrass ecology.