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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 #3 – 1200 PRINCESS ROYAL AVENUE
NANAIMO, BC V9S 3Z7
OFF-CHANNEL FISHERIES HABITAT CONSTRUCTED AT THE LITTLE QUALICUM ESTUARY.
PREPARED BY:
POLSTER ENVIRONMENTAL SERVICES LTD. 6015 MARY STREET
DUNCAN, BC V9L 2G5
AUGUST, 2011
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 non-
government 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, 2011.
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.
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. 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 non-
native 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. 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.
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. Re-
cutting 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.
LITERATURE CITED
Polster, D.F. 2009. 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, 2009.
Polster, D.F. 2011. 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, 2011.
SERI, 2004. The SER Primer on Ecological Restoration. Version 2. October, 2004. Science and
Policy Working Group, October, 2004. Society for Ecological Restoration International.
Tucson AZ. http://www.ser.org/content/ecological_restoration_primer.asp accessed
March 25, 2007
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