Bird conservation strategy for region 5: Northern Pacific rainforest, chapter 4

Executive summary

The Northern Pacific Rainforest, Bird Conservation Region (BCR) 5, extends from the western Gulf of Alaska south through British Columbia, Washington, Oregon, to northern California. In Canada, the terrestrial portion of BCR 5 is about 205,000 km² in extent, covering British Columbia from the coast inland though the Coast Mountains, and includes Vancouver Island and Haida Gwaii. It also extends northwards inland of the Alaska panhandle and includes a small corner of extreme southwestern Yukon Territory. This region encompasses the marine environment as well, from the coastline westward to the limit of Canada’s 200-nautical mile exclusive economic zone. BCR 5 is dominated by mountainous topography cut by numerous fjords and glacial valleys. Coastal waters are ice-free and associated with a narrow coastal shelf and slope. The region has some of the wettest climate in North America, with the north coast receiving up to 5,000 mm of rain a year. The oceanic influence also means temperatures are generally mild.

This conservation strategy for BCR 5 in the Pacific and Yukon Region (PYR) builds on existing bird conservation strategies and complements those created for the other BCRs across Canada. BCR strategies will serve as a framework for implementing bird conservation nationally, and also identify international conservation issues for Canada’s priority birds. This strategy is not intended to be highly prescriptive, but rather is intended to guide future implementation efforts undertaken by various partners and stakeholders.

The mild coastal climate and Pacific Ocean combine to create important bird habitats unique to this BCR. While estuaries form only a tiny fraction of the coastline, they are crucial habitat for a wide variety of waterfowl, seabirds and shorebirds. BCR 5 is also a major migration and wintering area for birds in Canada. Wetlands of the Fraser River delta and estuary are the most important wintering habitat for waterbirds in British Columbia, and the delta also supports millions of migrating shorebirds and the largest overwintering population of raptors in Canada. The Fraser River estuary’s importance has been widely recognized, both as a site of hemispheric importance under the Western Hemisphere Shorebird Reserve Network, a Ramsar site and an Important Bird Area.

Two hundred and ninety-three (293) species of bird regularly breed, overwinter or migrate through the Canadian portion of BCR 5.^{Footnote 1} Of these, 139 species were identified as priority species. All bird groups were represented on the priority species list, although the list is dominated by landbirds (41% of the total list) and waterbirds (27%). Over half of the waterbirds (56%) and waterfowl (62%) occurring in BCR 5 were identified as priority species, as compared to only 39% of the landbirds. Forty-six percent (46%) of the priority species are considered at risk, either federally or provincially.

Identifying the broad habitat requirements for each priority species within the BCR allowed species to be grouped by shared habitat-based conservation issues and actions. Coastal habitat types (including estuaries, rocky shorelines, mudflats and beach/dune habitats) and waterbodies (both marine and freshwater) are important for a broad suite of waterfowl, shorebirds, seabirds and even some landbirds. Forested habitats throughout the BCR, especially mature and old growth coniferous habitat types, are particularly important to a large set of priority landbirds. Also important to this bird group are herbaceous habitats, specifically the endangered Garry Oak ecosystem as well as old field habitats in the Lower Mainland and southeastern Vancouver Island.

The population objectives in this strategy are categorical and are based on a quantitative or qualitative assessment of species’ population trends. If the population trend of a species is unknown, the objective is set as “assess and maintain.” Over 63% of priority species, with representatives from all bird groups (landbirds, shorebirds, waterbirds and waterfowl), were assigned an objective to “assess” population status while “maintaining” current levels in the interim. For 6% of species, population levels were deemed to be at or near the objective. Five percent (5%) and 9% of species were assigned objectives to increase the population by 50% and to double the population, respectively. For a small proportion of species (6%), all listed under the federal Species at Risk Act (SARA), we have deferred to the population objectives developed in Recovery Strategies.

An assessment of threats identified a number of conservation issues facing priority species in the various habitats of PYR’s BCR 5. Residential and commercial development was recognized to be a very high threat across most terrestrial habitat types for many priority species (including waders like the Great Blue Heron, many shorebirds, and several raptor species, including owls). This is probably most true in southern parts of the BCR, such as the Lower Mainland and southeastern Vancouver Island. Logging and wood harvesting was identified as a very high threat in all forested habitats for many priority species (e.g., Northern Saw-whet Owl, Marbled Murrelet, Chesnut-backed Chickadee, Harlequin Duck). Invasive non-native species also emerged as a very high threat, particularly in coastal habitat. Many of these are colonial-nesting seabirds subject to predation by introduced mammalian predators (rats, racoons, mink) on offshore islands. Climate change also was identified as a very high threat, and again the list of affected species is dominated by seabirds, like Pink-footed Shearwater and Cassin’s Auklet, as warming sea surface temperatures are thought to be linked to lower ocean productivity. Climate change may manifest in the form of sea level rise, which may eliminate or severely reduce the extent of certain coastal habitats (e.g., mudflats) that are key migratory stopover foraging sites for shorebird species such as Western Sandpiper, Dunlin and Red Knot. Finally, oil pollution emerged as a high-level threat for a great number of seabirds and waterbirds (e.g., Black-footed Albatross, Common Murre, Pelagic Cormorant) that rely on coastal and offshore marine waters throughout the BCR.

Conservation objectives were designed to address threats and information gaps that were identified for priority species.They describe the environmental conditions and the research and monitoring that are thought to be necessary for making progress towards population objectives and for understanding underlying conservation issues for priority bird species. The majority of conservation objectives for BCR 5 relate to maintaining or enhancing habitat quality and quantity, and to reducing mortality or increasing productivity. Ensuring adequate habitat includes maintenance of the full range of naturally occurring habitat types, maintaining the quality of existing habitats, and retaining important features on the landscape (e.g., standing dead snags for cavity nesting birds). Reducing mortality includes addressing a wide suite of sources of accidental mortality, including bycatch in commercial fisheries, ingestion of plastic or lead shot, exposure to oil, collisions with human-made structures, destruction of nests, and pesticide poisoning.

Recommended actions identify on-the-ground activities that will help to achieve the conservation objectives. Actions are deliberately strategic rather than highly detailed and prescriptive. Whenever possible, recommended actions will benefit multiple species and/or respond to more than one threat. Given the importance in BCR 5 of conservation objectives relating to the maintenance and enhancement of habitat, it is not surprising that securing and protecting habitat emerges as a key theme. Actions relating to the development of beneficial management practices or other voluntary private sector codes of practice are similarly common, in part because site management and protection actions often have aspects that relate to the development of voluntary best practices. Another large set of recommended actions relate to policy and practices surrounding fisheries bycatch of seabirds. A significant proportion of actions fall into both the monitoring and research categories, indicating that knowledge gaps exist for specific species (relating either to a specific threat or current population status) where more information is required before conservation actions can be effectively formulated.