Management of Spartina anglica in the Fraser River estuary, British Columbia Gary Williams GL Williams & Associates Ltd. White Rock & Surrey Naturalists Society May 12 th, 2005 White Rock, BC
Presentation Outline Origin of S. anglica in England Identifying S. anglica Comparison with native species Fraser Delta management efforts
Origin of S. anglica S. maritima (native to SE England) S. alterniflora (Atlantic US ballast water) native & introduced species hybridized sterile F1 hybrid = S. townsendii fertile amphidiploid = S. anglica (through chromosome doubling) Hybrid Vigour higher rates of photosynthesis Increased sediment accretion More frequent tidal submergence
S. anglica (English cordgrass)
Comparison with Native Species Scirpus maritimus (seacoast bulrush) Salicornia virginica (pickleweed) Triglochin maritimum (seacoast arrowgrass) Distichlis spicata (saltgrass) Leymus (Elymus) mollis (dunegrass)
seacoast bulrush, Scirpus maritimus
Pickleweed, Salicornia virginica
arrowgrass, Triglochin maritimum
saltgrass, Distichlis spicata
dunegrass, Leymus (Elymus) mollis
Ecological Impacts of S. anglica Hybrid of S. maritima & S. alterniflora spread to 120 countries Aggressive invasive species replaces mudflats with mono culture reduces fish and waterfowl habitat accumulates sediments alters tidal drainage (mudflats & upland) out-competes native salt marsh species
Ecological Perspective Needed for Invasive Species Management
S. anglica a Regional Problem
Estuarine Nearshore Functions
Marine Nearshore Food Web
Steering Committee Pat Lim, Fisheries & Oceans Canada Kathleen Moore, Canadian Wildlife Service Dan Buffett, Ducks Unlimited Canada Verne Kucy, Corporation of Delta Ron Goldstone, BC Water Lands and Air Protection Tasha Murray, Vancouver Aquarium Juergen Baumann, Vancouver Port Authority Gary Williams, GL Williams & Associates Ltd. Wayne Mather, Greater Vancouver Regional District Kyle Murphy, WA Department of Agriculture Dave Heimer, WA Depart. of Fish and Wildlife Laural Shiner, Whatcom Cty. Noxious Weed Board Sally Hacker, Oregon State University Keeley O Connell, People for Puget Sound
Principles of Control Program Avoid the use of chemical herbicides high sensitivity of habitats difficult and lengthy process to obtain permits S. anglica infestation small enough for complete removal rapid, intensive response WA 2003 treated 6,000 acres at a cost of $1.5 million
S. anglica Management Program Identification & information review GW discovered in August 2003 Spartina key & DNA analysis Inventory & Planning Fraser estuary and Burrard Inlet GPS & GIS mapping (walking/hovercraft) Removal Manual and mechanical Outreach and Education NGO s, municipalities, conferences
S. anglica Identification California Coastal Conservancy www.spartina.org Barkworth (2003) S. Riggs, Padilla Bay National Estuarine Research Reserve Cindy Sayre, UBC Herbarium D. Ayres, Univ. CA, DNA analysis
DNA Analysis (courtesy D. Ayres) Gel image of S. anglica (first 2 lanes) and S. alterniflora x foli hybrids Band is absent in S. alterniflora (and S. foli) S. maritima band in S. anglica
Hovercraft Inventory Hovercraft surveys Nov. 2003 Oct. 2004
Distribution in Boundary Bay & Roberts Bank
Area of Impact of Impact
Regrowth of S. anglica
2003 Roberts Bank Manual Removal
2004 Manual Removal Methods
2004 Mechanical Removal (in situ burial)
Schedule of Spartina Removal Date Manual Removal Roberts Bank Excavator Boundary Bay Manual Removal Excavator Sep. 2003 Oct. 24, 2003 Jun. 17-19, 2004 Jun. 23, 2004 Aug. 3 & 12, 2004 Aug. 5, 2004 Sep. 2, 2004 Sep. 25, 2004 Oct. 13-14 clip seedheads
Costs for 2004 Program $39,000 for consulting, excavator, materials, labour, and equipment $79,000 in-kind support Combined costs of $118,000 Removed over 7500 kg of Spartina Estimated Area: 248 ha Roberts Bank = 65 ha (0.2 ha solid) Boundary Bay = 183 ha (1.4 ha solid)
Funding Vancouver Port Authority Environment Canada, Canadian Wildlife Service Ducks Unlimited Canada Fisheries and Oceans Canada Greater Vancouver Regional District Water Land and Air Protection Western Regional Panel BC Inter-Ministry Invasive Plant Committee
Volunteers Over 100 volunteers Vancouver Aquarium, Riverworks Langley Environmental Partners Society The Nature Trust Puget Sound Action Team Northwest Wildlife Whatcom County UBC student Plus numerous individuals from Steering Committee agencies
A Matter of Choices