Anne Murray: First-ever online B.C. Breeding Bird Atlas finds many bird species are on the move

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      Did you know there are two different species of hummingbirds in the Vancouver area? The rufous hummingbird is a tiny orange-red hummer that visits B.C. each summer and winters in Mexico, while the slightly larger maroon-and-green Anna’s hummingbird is here all year.

      Anna's hummingbirds have increased their numbers in B.C. dramatically in the past two decades in response to the warmer climate and availability of year-round food. It is on the front cover of the new Birder’s Guide to Vancouver, and it is one of many bird species spreading across the province, as demonstrated by the newly released British Columbia Breeding Bird Atlas. The atlas was published online this month, coinciding with Vancouver Bird Week, International Migratory Bird Day, and the 100th anniversary of the 1916 Migratory Bird Treaty Act.

      The B.C. Breeding Bird Atlas is based on an unprecedented five-year field survey carried out by an army of enthusiastic volunteers and coordinated by the nonprofit group Bird Studies Canada (BSC). Its completion required more than 56,000 hours of fieldwork that collected more than 630,000 records. This massive collaborative effort involved impressive numbers of people: 1,300 field volunteers, 40 writers and editors, 45 regional coordinators, 40 photographers, and 150 partners and special contributors.

      First-ever free web-based bilingual bird atlas worldwide

      The result is the first entirely web-based, free of charge, fully bilingual breeding bird atlas in the world. All 320 species accounts—plus maps, graphs, tables, and raw data—are available on the website in an easy-to-use format.

      Many discoveries were made about the distribution of both common and rare birds during this systematic atlassing of the B.C. landscape. Although the birds of the Lower Mainland are well known to keen birders, exciting new finds occurred in more remote regions. Uncommon birds such as yellow rails and wandering tattlers were located in distant areas of the province.

      The atlas also identified long-term changes. Waterfowl are doing well, while other bird families, such as some of the grebes, swallows, and flycatchers, are disappearing—in some cases, quite dramatically. Peregrine falcons have increased in number at the same time as prairie falcons have declined. Some birds, like the Anna’s hummingbird, are expanding their breeding ranges. Long-billed curlews were known to breed in the Kamloops and Kootenays grasslands but were found nesting further north. Birds of the dry Southern Interior valleys, such as Lewis’s woodpecker, lazuli bunting, gray flycatcher, and gray catbird, were found to be moving both north and westward.

      Some tundra species moving south

      In contrast, a few tundra-loving shorebird species—greater and lesser yellowlegs, least sandpiper, and American golden plover—were found breeding in montane central parts of the province, much farther south than previously known.

      General patterns were found for some groups of species, but for others, similar species are faring very differently, like the populations of three colourful warblers, all spruce-budworm specialists. Tennessee warblers were found to be exploding west and northwards, while the Cape May warbler is gradually expanding westward, and the bay-breasted warbler’s range remains unchanged. Other boreal-forest birds, like the Canada warbler, blue-headed vireo, and rose-breasted grosbeak, found in the northeast of B.C., may also be moving west. These migratory songbirds all spend the summer in the northern forests and winter in tropical Central or South America.

      The ecological consequences of these population changes and range expansions will need more research, and the atlas is now an important source for students, universities and government departments exploring the effects of habitat and climate change around the province.

      Bird atlassing is done around the world. I remember taking part in the very first atlas in Britain in 1970. In Canada, the B.C. Atlas complements atlases completed or under way in Ontario, the Maritimes, Quebec, and Manitoba.

      Birds identified in 10,000 10-kilometre squares

      Atlases follow a standardized method of bird-surveying. Evidence of breeding for different species is established within a provincewide grid of 10-kilometre squares by listening for singing birds, finding nests, or spotting young birds or adults carrying food for chicks. Song-identification skills were particularly tested during point counts that helped estimate the numbers of birds, such as the many migratory warblers, flycatchers, and vireos that spend the summer in boreal forests. To ensure equitable coverage of both familiar, well-populated areas and the remote regions, the number of hours spent searching for birds was strictly limited for each 10-kilometre square over the five years of atlassing.

      Atlassing birds is a challenging, physically active, yet fun pursuit, and it is a fascinating way to get to know the natural environment. The adventures begin when birdwatchers head into the backcountry, looking for birds by hiking up mountains or exploring by cycle, kayak, or horseback. Every sense is alerted, listening for bird song, watching for the flutter of wings in the foliage, and even keeping an eye open for bears feeding in the same berry bushes you are busy surveying! Wendy Boothroyd and her son Malcolm recorded five grizzlies and eleven black bears on an Alaska Highway section while atlassing by bicycle.

      Volunteers for the B.C. Atlas included both amateur and professional birders. People all over the province came together to offer logistical help, including guide-outfitters, floatplane owners, and environmental-management companies and organizations, as well as members of B.C. nature clubs and the B.C. Field Ornithologists. Other partners included Environment Canada, the B.C. Ministry of Environment, the Pacific Wildlife Foundation, and LP Building Products. As Rosamond Pojar, regional coordinator for the Bulkley Valley atlas region described: “It is big country up there, and you just cannot walk from one valley to another in a short time.” With 10,000 squares to be covered, the atlas would not have been accomplished without dedication and some really serious support.

      Breeding western scrub jays in Maple Ridge a first

      Whether it was climbing mountains or birding in their backyard, everyone who participated in the atlas has lasting memories. Project manager Peter Davidson said: “The thrill of discovery is a feeling that lifts us all. The atlas gave everyone, from beginner to expert, an opportunity to discover. Every encounter that lit up a new map square was a thrill—even the process of entering data became exciting!”

      New discoveries were often made close to home; Davidson climbed a gruelling 1,000 metres above Chilliwack Lake and found boreal chickadees breeding at the southwestern limit of their range. Western scrub Jays were breeding in Maple Ridge—the first time the species has bred anywhere in Canada!

      Between them, Margo Hearne and Peter Hamel atlassed much of northern Haida Gwaii, on foot and by boat. In Masset Inlet, Hearne describes seeing “a number of sandhill-crane chicks, tiny golden dots running along the shore with their parents; many black-oystercatcher chicks trying to hide behind clumps of seaweed on the rocky islets as we approached. Hiking the muskeg bogs, we could hear red-throated loons far in the distance and knew they were back on their nesting grounds". For her and Hamel, "the songbirds were ever a delight, and to see fox sparrows and pine siskins feeding fledged young made all those early morning excursions worthwhile".

      Volunteer atlassers shared unforgettable experiences

      Joanne Vinnedge, regional coordinator for the Fraser Plateau, described her atlassing experience in one of the project’s newsletters: “It makes me really stop and take careful note of what’s going on. And I like to think that I’ve managed to make a wee bit of difference in my small town and opened some people’s eyes to the birds around them.”

      I am personally proud to have also played a small part in this huge collaborative effort, atlassing in Delta, the Gulf Islands, Wells Grey Park, and, for 10 glorious days, on horseback through Itcha Ilgachuz Provincial Park, in the West Chilcotin Uplands, with a team led by John Woods and outfitters Roger Williams and Wanda Dorsey from Six Mile Ranch. Waking to frost on the tent, singing Lincoln’s sparrows, and the drumming of horses’ hooves were just some of many unforgettable experiences.

      The National Atlas Program is not only finding where breeding birds occur but also identifying which birds require conservation help and where habitat should be protected. As Davidson told me: “Some of the best moments from the atlas have yet to happen. They will come when the information is used to protect land, recover species at risk, keep common birds common, and inspire others to fill the gaps that we could not.”

      The B..C Breeding Bird Atlas fills in the knowledge gaps for our province and sets a benchmark to evaluate the effects of the changing climate on bird life. The results from this important work should serve to guide the protection and management of bird habitat into the future, for both common birds and species at risk.

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