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K'omoks (BC272)

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K'omoks (BC272)

Comox, British Columbia

Latitude 49.624°N
Longitude 124.873°W
Altitude 0 - 200m
Superficie 560.73km²

Site Description

The K'omoks IBA, along the east-central coast of Vancouver Island near the city of Courtenay, is an extensive network of marine waters, estuaries, backshore areas and associated lowland valley bottoms. Inland lowlands are a mixture of agricultural areas and forested land. Forests are predominately Coastal Douglas-fir and Western Hemlock while some dry Garry Oak/Douglas-fir forest occupies drier sites. An extensive estuary ecosystem extends from K'omoks Estuary through Baynes Sound to Deep Bay and Mapleguard Point, approximately 30 km to the southeast. Baynes Sound is a shallow coastal channel fringed by protected bays, open foreshore, tidal estuaries and inshore marshes. The shoreline includes wide expanses of mud and sand flats, low gradient deltas and sand and gravel beaches. This area is the most important intertidal area in B.C. for oyster and shellfish aquaculture. Further offshore, Lambert Channel and the marine waters surrounding Hornby Island have mostly rocky shores and rocky headlands, that provide extensive feeding and resting areas for waterbirds, especially during herring spawn in late-winter and early-spring.

The K'omoks IBA is an amalgamation of the former Comox Valley IBA, Baynes Sound IBA and Lambert Channel/Hornby Island Waters IBA. These three IBAs share common populations of waterbirds but were established as separate IBAs because they were nominated independently; follow the links to access the original site information.

Birds

This IBA is designated for four species at the global level: Trumpeter Swan, Harlequin Duck, Thayer's Gull, Glaucous-winged Gull; one species at the continental level: Mew Gull; and two species at the national level: Great Blue Heron and Peregrine Falcon. Continentally significant numbers of Waterbirds occur each year and, in some years, globally significant numbers have been recorded for Surf Scoter and Western Grebe and continentally significant numbers for White-winged Scoter and Red-necked Grebe.

The Comox Valley is notable for the numbers of Trumpeter Swan that over-winter there. Based on regular surveys, the numbers of swans increased to the late-1990s and have stabilized at an over-wintering (February) population of over 2,100 birds, with peak counts of over 2,900 birds. The swans arrive in late October and have mostly departed by early April. They feed on discarded vegetables or corn cobs, green forage between harvested corn, and seedlings of various winter cover crops, as well as native vegetation in the estuary.

Aggregations of Harlequin Duck gather at a few locations on the northeast side of Hornby Island during herring spawn. These aggregations can include 49-81% of the midwinter population of Harlequin Duck in the northern Strait of Georgia. An estimated 3,400-5,500 birds were present in 1996-2001. Aggregations occur in only a small fraction of the habitat area where spawn is available, indicating the importance of the site. During summer and early fall, the shores of Hornby Island are also a major roost site for moulting Harlequin Duck. Systematic surveys have not been conducted since 1996-2001, but regular shore-based counts indicate that the Harlequin Duck population appears to be stable (shore-based counts are lower than those obtained from a systematic survey).

Aggregations of 30,000-60,000 Waterbirds occur each year during herring spawn. About a third of those birds are waterfowl, including significant numbers of Surf Scoter and White-winged Scoter in some years, and about 60% are gulls, including significant numbers of Mew Gull, Thayer's Gull and Glaucous-winged Gull.

Historically, Western Grebe wintered here in globally significant numbers, with high counts ranging from 1345-4700 birds between 1978 and 1997. However, the numbers have declined steeply since then and only one count (2003) was close to the 1% global threshold. This significant decline has been noted throughout the Salish Sea (British Columbia and Washington); the reasons for the decline are not clear but may be related to a decrease in forage fish and a subsequent southerly shift in wintering areas.

Red-necked Grebe was recorded at continentally significant levels in early September 2007 and 2012. The Deep Bay area may be a significant fall moulting area for this species but more study is needed as there have been few comprehensive surveys at that time.

The IBA supports important numbers of three species determined to be Threatened or Special Concern by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC; wildlife species that have been assessed as at risk by COSEWIC may qualify for legal protection and recovery under Canada's Species at Risk Act). Great Blue Heron (fannini subspecies) (Special Concern, COSEWIC) has several colonies in the IBA (up to 100 individuals). Marbled Murrelet (Threatened, COSEWIC; and Endangered, the International Union for Conservation of Nature, IUCN) occurs regularly in the IBA most of the year (peak counts of at least 50-100 individuals). Peregrine Falcon (Special Concern, COSEWIC) winters regularly in the IBA and 1-2 pairs nest there.

Conservation Issues

The number of people living in the IBA has doubled over the past 20 years and is expected to continue to increase. Impacts associated with increased development, including discharges from sewage and suburban storm sewers, wetlands being filled in, and new housing developments and associated commercial/industrial areas reduces the amount, and degrades the quality, of habitat for Trumpeter Swan and other waterbirds. Loss of soil-based agriculture also reduces habitat available for swans. From 1992 to 2002, at least 5% of the sensitive ecosystems and over 29% of modified ecosystems such as older second growth forests and seasonally flooded agricultural fields were lost to other uses. Disturbance from increased recreational activities also poses a potential threat to bird populations using the area.

Many of the species using this IBA are dependent on herring spawn. Any activity that negatively impacts the herring spawn (e.g. reductions in water quality, foreshore development) could have significant impacts on the ability of this site to support a concentration of birds. The recent demand for expanded aquaculture development will need to continue to be evaluated carefully for its impact on birds.

There is limited legislated protection in place for the marine waters; the most significant is the marine extension to Helliwell Provincial Park. On the uplands, there is a National Wildlife Area and several Provincial and Regional Parks, mostly forested habitat. Several areas of upland habitat are owned or managed for wildlife conservation, especially for Trumpeter Swan and waterfowl, by Ducks Unlimited Canada and The Nature Trust of British Columbia. As well, the Comox Valley Waterfowl Management Project (Ducks Unlimited Canada and Canadian Wildlife Service) is a cooperative farm and wildlife extension program established to maintain wintering waterfowl populations in harmony with successful farming.

An IBA Conservation Plan was written for part of the IBA (2001), but needs to be updated. Specific conservation strategies will vary across the IBA to reflect differences in habitats and threats. The IBA is recognised in the Comox Valley Conservation Strategy (Nature Without Borders) and in some Official Community Plans.

Within the IBA, members of the Comox Valley Naturalists Society have been conducting standardised bird monitoring for five decades: Christmas Bird Counts since 1961, Spring Bird Counts since 1976, weekly Trumpeter Swan Counts since 1990, as well as other bird counts. Volunteers also have been collecting monthly counts for the British Columbia Coastal Waterbird Survey since 1999 and monthly surveys for the British Columbia Beached Bird Survey since 2002.

Catégories ZICO Habitats Usages Menaces Potencielles ou Existantes Status de Protection
Iceland Gull (Thayer's)
Number Year Season
802017Spring
200 - 1,0002017Winter
240 - 7772016Winter
100 - 2202016Fall
136 - 4002016Spring
300 - 1,3672015Winter
150 - 2002015Fall
100 - 1,0002015Spring
151 - 6002014Winter
90 - 1402014Fall
850 - 2,0002014Spring
195 - 3392013Winter
200 - 3002013Fall
500 - 8002013Spring
328 - 6702012Winter
80 - 1052012Fall
200 - 5002012Spring
129 - 5182011Winter
86 - 3592011Fall
100 - 4002011Spring
123 - 3172010Winter
1502010Fall
200 - 5002010Spring
120 - 2362009Winter
105 - 3452009Fall
1502009Spring
135 - 1,5012008Spring
78 - 1272008Winter
79 - 1192007Winter
88 - 3502007Fall
300 - 2,0002007Spring
100 - 2542006Winter
150 - 2842006Spring
87 - 1382005Winter
1672005Fall
112 - 5002005Spring
81 - 2692004Winter
140 - 8002004Spring
192 - 1,2002003Winter
1172003Fall
111 - 4002003Spring
922002Winter
210 - 2252002Fall
200 - 2962002Spring
104 - 4502001Winter
1102001Fall
97 - 2602001Spring
166 - 3592000Winter
100 - 1,0002000Spring
77 - 4961999Winter
1181998Winter
94 - 1111995Winter
1971994Winter
2601993Winter
1201992Winter
Trumpeter Swan
Number Year Season
284 - 4302017Winter
320 - 4502016Winter
290 - 5782015Winter
279 - 1,0912014Winter
400 - 1,4652013Winter
3002013Spring
340 - 2,5502012Winter
4002012Fall
407 - 2,2742011Winter
310 - 2,1792010Winter
360 - 6502010Fall
2602010Spring
300 - 2,1192009Winter
289 - 2,9062008Winter
306 - 2,2562007Winter
1,796 - 2,8042006Winter
6002006Fall
481 - 2,3602005Winter
461 - 1,4742004Winter
910 - 2,9392003Winter
400 - 1,1952002Winter
400 - 1,5602001Winter
270 - 1,9042000Winter
1,2791999Winter
315 - 1,2211998Winter
1,4941997Winter
1,0111995Winter
8021994Winter
7421993Winter
1,0981992Winter
4151991Winter
7151990Winter
Glaucous-winged Gull
Number Year Season
9,0252017Spring
5,0002016Spring
5,000 - 32,0002014Spring
5,000 - 8,0002013Spring
4,6972012Winter
7,5482011Spring
4,3632010Winter
5,000 - 8,0002010Fall
4,300 - 45,0002010Spring
5,6692006Spring
4,3102005Winter
6,914 - 6,9252004Winter
7,0002004Spring
9,2442003Winter
6,8662002Winter
8,5972001Winter
8,0002001Spring
5,6852000Winter
6,3101997Winter
7,5251995Winter
4,5561994Winter
4,4981991Winter
Western Grebe
Number Year Season
1,1202010Fall
6,3402005Winter
1,000 - 1,1322003Fall
2,0002003Spring
2,1221997Winter
1,5161994Winter
3,0811991Winter
Brant
Number Year Season
15,5012012Spring
Surf Scoter
Number Year Season
8,0002016Spring
6,000 - 8,0002015Spring
5,9662014Winter
11,0002014Spring
11,4762012Spring
25,0002010Spring
6,5962009Spring
5,9312005Spring
15,0002003Spring
Black Oystercatcher
Number Year Season
1782015Winter
1922014Winter
1542013Winter
1002011Winter
1672010Winter
1182009Winter
1122007Winter
882006Winter
782005Winter
812004Winter
791995Winter
Pelagic Cormorant
Number Year Season
9002017Winter
Black Turnstone
Number Year Season
1,0002004Fall
1,0002002Fall
Marbled Murrelet
Number Year Season
5102016Spring
822008Spring
942006Spring
43 - 602004Spring
46 - 752003Spring
442002Fall
Mew Gull
Number Year Season
6,0252017Spring
2,5002016Spring
2,500 - 4,0002013Spring
4,2552008Spring
2,800 - 4,1682007Spring
2,9152006Spring
3,3412004Spring
2,5002003Spring
2,990 - 9,0002001Spring
Red-necked Grebe
Number Year Season
5002017Fall
368 - 4002016Fall
358 - 5502013Fall
5652012Fall
601 - 8222007Fall
4002005Spring
3972004Fall
4092003Spring
White-winged Scoter
Number Year Season
5,9942004Winter
5,1672004Fall
5,0852003Spring
5,0332003Winter
Heermann's Gull
Number Year Season
1002014Fall
3352009Spring
612008Winter
352006Spring
Great Blue Heron
Number Year Season
37 - 552016Summer
532015Winter
442014Winter
562012Spring
682011Spring
1022010Spring
412009Winter
492009Spring
532008Spring
462007Fall
382007Summer
482007Spring
35 - 442006Winter
602005Winter
45 - 762005Spring
552004Winter
55 - 632004Fall
46 - 942004Spring
562003Winter
542003Fall
38 - 842003Spring
392002Winter
552002Fall
732002Spring
392001Winter
442001Fall
35 - 611999Winter
35 - 611998Winter
561997Winter
431995Winter
34 - 351994Winter
531993Winter
861992Winter
1061991Winter
691990Winter
Western Screech-Owl
Nombre Année Saison
12009Winter
12004Winter
12003Spring
12001Winter
12001Fall
12000Winter
22000Spring
21999Spring
11999Winter
21998Spring
Waterbirds
Nombre Année Saison
32 7412011Spring
21 0662011Winter
60 5372010Spring
26 2322010Winter
21 8122009Spring
22 2622009Winter
47 6842008Spring
38 0972007Spring
33 0542006Spring
50 4572005Spring
54 5712004Spring
28 9532003Spring
24 2962003Winter
28 5182002Spring
20 6042002Winter
Greater Scaup
Nombre Année Saison
5 0002010Spring
Surfbird
Nombre Année Saison
5302015Spring
6002014Winter
6002013Winter
6002012Fall
California Gull
Nombre Année Saison
5 0002016Spring
Harlequin Duck
Nombre Année Saison
1 4692007Spring
1 4772006Spring
1 0992005Spring
1 5872004Spring
1 0942003Spring
1 2212002Spring