LITTLE QUALICUM ESTUARY RESTORATION PROJECT QUALICUM BEACH, BC

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LITTLE QUALICUM ESTUARY RESTORATION PROJECT QUALICUM BEACH, BC PREPARED

, SENIOR FISHERIES BIOLOGIST LIVING RIVERS - GEORGIA BASIN/VANCOUVER

NANAIMO, BC V9S 3Z7 OFF-CHANNEL FISHERIES HABITAT CONSTRUCTED AT THE

1 LITTLE QUALICUM ESTUARY RESTORATION PROJECT QUALICUM BEACH, BC PREPARED FOR: J.C. (CRAIG) WIGHTMAN, R.P.BIO., SENIOR FISHERIES BIOLOGIST LIVING RIVERS - GEORGIA BASIN/VANCOUVER ISLAND BC CONSERVATION FOUNDATION # PRINCESS ROYAL AVENUE NANAIMO, BC V9S 3Z7 OFF-CHANNEL FISHERIES HABITAT CONSTRUCTED AT THE LITTLE QUALICUM ESTUARY. PREPARED BY: POLSTER ENVIRONMENTAL SERVICES LTD MARY STREET DUNCAN, BC V9L 2G5 AUGUST, 2011

2 INTRODUCTION Restoration is the process of assisting the recovery of ecosystems that have been damaged, degraded or destroyed (SERI 2004). The key to effective restoration is to determine the factors that might be constraining recovery on the site in question (Polster 2011). Restoration then becomes a matter of simply overcoming these constraints or filters and allowing the natural processes to restore the site. The Little Qualicum Estuary is a complex site. The sandy/gravel spit associated with the estuary is the only estuarine spit on the east coast of Vancouver Island that has not been subjected to development. As such it serves a valuable role in the ecology of the region and has been afforded protection with the establishment of the Little Qualicum River Estuary Regional Conservation Area (LQRERCA). The LQRECA is a partnership (79:21) between Ducks Unlimited, representing a range of government and nongovernment environmental groups and the Regional District of Nanaimo. An extensive area of fisheries habitat enhancement was constructed in 2000 (see cover photograph). At that time a significant part of the LQRERCA was cleared with the cleared area being seeded to agronomic grasses and legumes. Although the seeded species have established a very productive cover due to the coarse texture of the soils, the green vegetation and the lack of impediments has allowed high populations of Canada Geese to move into the area. In addition, the seeded vegetation cover attracts deer that then make use of the limited native woody vegetation that has established on the spit. Significant efforts are being undertaken to address the goose problem without reducing the ecological values of the estuary (Photograph 1). This brief report has been prepared to provide suggestions for the restoration treatment of the estuary and particularly the LQRERCA. The report is organized to present the ecological filters or constraints that were identified during a site visit on June 14, This is followed by recommendations for addressing the filters as well as suggestions for monitoring. FILTERS (CONSTRAINTS) TO RECOVERY Herbivory is the dominant filter operating at the LQRERCA site. As noted above, geese and deer are causing significant ecological problems at the site (Photograph 2). Seeding the spoil areas of the fisheries enhancements that were constructed in 2000 and the lack of significant predation has encouraged hyper-abundant populations these animals. Ecological degradation is the result of this biotic filter (Polster 2009). In addition to the seeding, there appears to have been a loss of large woody debris on the spit during the construction activities.

3 Photograph 1. An area of flight obstructions has been established on a portion of the estuary in a test designed to determine if this approach will prevent geese from destroying the area. Photograph 2. The trim line on this clump of native hawthorn (Crataegus douglasii) is indicative of the heavy pressure by deer while the close cropping of the grass is caused by geese.

Invasive species can also cause substantial ecological degradation. Efforts to remove invasive species from the spit have been undertaken.

Managing ecosystems in a healthy state can reduce the invasion by nonnative species although in the case of herbaceous areas such as Garry Oak Ecosystems and portions of the LQRERCA site, invasive

aurea) is moving into the spit, probably as a result of the ecological degradation caused by the geese.

4 Invasive species can also cause substantial ecological degradation. Efforts to remove invasive species from the spit have been undertaken. However, new invasive species are starting to appear (see Photograph 3), probably as a result of the degradation caused by the herbivory. Managing ecosystems in a healthy state can reduce the invasion by nonnative species although in the case of herbaceous areas such as Garry Oak Ecosystems and portions of the LQRERCA site, invasive species such as Scotch Broom (Cytisus scoparius) and Blackberry (Rubus discolor) will invade even reasonably healthy sites. Photograph 3. An ornamental Stonecrop (Sedum acre var. aurea) is moving into the spit, probably as a result of the ecological degradation caused by the geese. RECOMMENDED RESTORATION TREATMENTS Fencing and construction of flight barriers (Photograph 1) are not natural methods of preventing the adverse impacts of geese and deer, although the use of flight barriers may be effective in areas where other methods cannot be used. Re-establishment of a relatively dense cover of large woody debris over the spit area may be the most effective way of preventing the adverse effects of herbivory without destroying the ambience of

the area. Photograph 4 shows a site on the spit where natural beach logs are limiting access by deer and geese.

In addition, the heavy browsing on woody species noted in other areas of the spit was not seen in this area, although this may be due to the position of this site near the end of the spit that may

Many native species were seen in these areas that are not occurring on the rest of the spit.

5 the area. Photograph 4 shows a site on the spit where natural beach logs are limiting access by deer and geese. The flora in this area has responded to this lack of herbivory by allowing native species such as Bare-stemmed Desert Parsley (Lomatium nudicaule) to establish. In addition, the heavy browsing on woody species noted in other areas of the spit was not seen in this area, although this may be due to the position of this site near the end of the spit that may limit deer access. Photograph 4. A natural collection of large woody debris is limiting the access to this area of the spit by deer and geese. Many native species were seen in these areas that are not occurring on the rest of the spit. Large woody debris could be established in the fisheries channel as well as on the upland areas of the spit. The tidal effects could be offset by using large stumps such as the one shown in the cover photograph to lock the large woody debris in place. Care should be taken to avoid chaining or cabling the woody debris to hold it in place as the movement of this material over the years is one of the natural features that allow the spit vegetation to develop. Ideally, beach logs and stumps would be used to treat the LQRERCA site.

6 However, this material plays an important role on the beaches where it occurs and the movement of it from the beach areas to the spit would result in degradation of the beach areas. Fresh materials collected from upland land clearing activities could be used. Although this large woody debris may look out of place for a few years, the severe weather conditions associated with the spit will ensure that the woody debris gains a weathered look relatively quickly. The quantities of woody debris that will be needed and the logistics of moving this material onto the spit will need to be determined in concert when the details of where the material is to come from are known. As a start, the density of woody debris shown in Photograph 4 would appear to be adequate. Within the fish channel however, large stumps will need to be placed at strategic locations to prevent the movement of the woody debris out of the channel area. Deer fencing may be needed near the residence to prevent deer from moving from the residence down the spit to the LQRERCA area. As with the quantities and placement details, the need for fencing will have to be determined once the large woody debris has been established. Ideally, fencing would not be needed, but if the geese are prevented from accessing the spit, then the seeded grasses may recover to the point where they are too tempting for the deer. Continued efforts to remove invasive species will need to be continued. Groups such as the Qualicum Beach Streamkeepers could provide a valuable service by monitoring the area for invasive species and arranging for removal when they occur. Care should be taken to avoid soil disturbances during invasive species removal programs and species such as Scotch Broom and Blackberry should be cut at the soil surface with the cut stumps covered with a bit of leaf litter and duff to prevent (or limit) re-sprouting. Recutting should be continued frequently as needed following the initial cutting to reduce stored energy reserves and cause the cut plants to die. Monitoring this area over the years ahead should focus on determining if the treatments that have been applied are succeeding in shifting the ecological conditions of the site in favour of recovery. Although a detailed monitoring program could be established and might provide some interesting data on recovery processes, a detailed program is not required and casual observations several times a year can serve to determine if the treatments are having the desired effects. If it is determined that the treatments have not succeeded in allowing recovery, then additional treatments may be needed. Care should be taken initially to avoid over-treating the site as significant changes could be met with opposition from local residents. Keeping all interested parties informed of the treatments that are being considered will be the most effective way of ensuring acceptance.

7 LITERATURE CITED Polster, D.F Natural Processes: The Application of Natural Systems for the Reclamation of Drastically Disturbed Sites. paper presented at the B.C. Technical and Research Committee on Reclamation, BC Mine Reclamation Symposium. Cranbrook, B.C. September 14-17, Polster, D.F Effective reclamation: Understanding the ecology of recovery. paper accepted for presentation at the 2011 Mine Closure Conference and B.C. Technical and Research Committee on Reclamation, BC Mine Reclamation Symposium. Lake Louise, AB. September 18-21, SERI, The SER Primer on Ecological Restoration. Version 2. October, Science and Policy Working Group, October, Society for Ecological Restoration International. Tucson AZ. accessed March 25, 2007

The Ecology of Recovery: from mines to marshes. Frank Slide. How does this happen? Over time natural processes restore these sites

The Ecology of Recovery: from mines to marshes David Polster Polster Environmental Services Ltd. Ecological restoration is the process of assisting the recovery of an ecosystem that has been degraded,