Forest, Range & Recreation Resource Analysis Table of Contents
2.5 Biological Diversity
Biological diversity (“biodiversity”) refers to the variety of life and its processes. Biodiversity is generally considered at three levels: genetic diversity, species diversity and ecosystem diversity. Two genetic diversity issues of particular interest in the realm of forestry are the genetic diversity of conifer species and of salmon. The genetic diversity of most species is so poorly known that the topic is not considered here.
2.5.1 Species Diversity
British Columbia has high species diversity considering its northerly latitudes (48°14’ to 60°N), the preponderance of rock, ice and snow in much of its landscape, and its relatively recent glaciation (10 000 years ago in some areas). British Columbia probably has greater biological diversity than Oregon and Washington combined and is certainly more diverse physiographically, ecologically and biologically than any other Canadian province or territory or Alaska. Native vascular plants illustrate this point: about 2 500 species occur in B.C., 1 775 in Alberta and 1 600 in Alaska and the Yukon combined. British Columbia contains over half of the 4 150 species of vascular plants estimated to occur in Canada.
Plants
Endemism in the flora (that is, plants restricted in their occurrence to B.C.) is generally low, although there are several endemic taxa on the Coast, especially on the islands (including Vancouver Island and the Queen Charlotte Islands). The centres of plant richness and rarity in B.C. are the dry southern Interior, the Peace River area and the Strait of Georgia complex of grassland, parkland, dry forest, rock outcrop, vernal meadow and pool or seepage vegetation, collectively called “saaniche.”
Mosses, liverworts and hornworts also display great richness in B.C. About 700 species of mosses occur in B.C., compared to 900 in all of northwestern North America (Alaska, Yukon, B.C., Alberta, Oregon, Washington, Idaho and western Montana). British Columbia has about 250 species of liverworts or hornworts — nearly all those that inhabit northwestern North America.
More than 75% of Canada’s bryophyte species are represented in B.C. Some 30 genera and 60 species in Canada are found only in B.C. Bryophytes are especially diverse and prominent in coastal forests. Endemism is not high but is concentrated on the Queen Charlotte Islands and adjacent island groups. Unusual species are concentrated on the very wet outer Coast; the semi-arid southern Interior also has a few. Rare or endangered bryophytes are mainly those at their northern or southern range limits, are restricted endemic species or rare throughout their range.
Lichens
Knowledge of the province’s lichens is sketchy; the recently published Lichens of British Columbia is the first available guide to these organisms.[8] The only large areas in which lichens have been intensively collected are the Queen Charlotte Islands and Strait of Georgia area. The most recent B.C. checklist added about 50 species to the North America lichen flora of 3 400 species. British Columbia has most (nearly 85%) of the 1 200 species that occur in northwestern North America. The province has noteworthy epiphytic communities of both lichens and bryophytes, as one would expect of a moist, mountainous region fronting the ocean. Arctic-alpine and Pacific-maritime elements are well represented. Some wide-ranging genera of macro-lichens are very well represented in B.C. For example, 15 of the 20 North American species of Hypogymnia occur here, as do 20 of 28 species of Umbilicaria and 23 of 30 species of Cetraria.
Fungi
Despite the fundamental roles fungi play in nutrient and energy dynamics, knowledge about them is lacking. Much of the existing knowledge of fungi is limited to species that are economically important, showy, tasty, dangerous, pathogenic or especially lurid. An estimated 10 000 species of fungi are found in B.C., including up to 3000 mushroom species. We know so little of lower fungi (e.g., phycomycetes) that meaningful estimates of their species richness are impossible — it would be surprising if 20% of the province’s species are known. British Columbia is believed to have more kinds of fungi than the Prairies or Maritimes and about the same number as Ontario and Quebec, which are enriched by southern, deciduous forest species.
Animals
The richness of B.C.’s fauna parallels the richness of its flora. British Columbia has more than 70% of Canada’s 454 bird species, in terms of both the provincial total and breeding species. British Columbia has about 300 species of breeding birds — more than any other province and nearly half the total for the continental United States; 162 of these do not breed anywhere else in Canada. These 162 species include Marbled Murrelet, Ancient Murrelet, Rhinoceros Auklet, Tufted Puffin, Spotted Owl, Flammulated Owl, White-headed Woodpecker, White-throated Swift, Anna’s Hummingbird, Gray Flycatcher, Canyon Wren and Hutton’s Vireo.
Species with a centre of distribution in B.C. include Harlequin Duck, Barrow’s Goldeneye, Bald Eagle, Blue Grouse, Common Poorwill, Rufous Hummingbird, Lewis’ Woodpecker, Sage Thrasher, Black-headed Grosbeak, Golden-crowned Sparrow, Cassin’s Finch and American Dipper.
British Columbia has internationally significant populations of Barrow’s Goldeneye, Blue Grouse, White-tailed Ptarmigan, Black Oystercatcher, Ancient Murrelet, Marbled Murrelet, Cassin’s Auklet, Rhinoceros Auklet, Rufous Hummingbird, Northwestern Crow, Varied Thrush, Townsend’s Warbler and Golden-crowned Sparrow, as well as raptors like Osprey, Bald Eagle and Peregrine Falcon.
The province is a major migration corridor and staging area for species such as Brant, Sandhill Crane, Hammond’s Flycatcher and Vaux’s Swift. The centres of bird diversity occur in the southern Interior and southwest B.C. The Fraser Lowland (especially the Fraser River delta) provides internationally significant, critical wintering habitat for many species.
British Columbia has about 110 species of terrestrial mammals, nearly 80% of the Canadian total. In comparison, Ontario has 77 and the continental United States has 315. Twenty-five of B.C.’s terrestrial mammal species and 12 marine species occur nowhere else in Canada. British Columbia contains more large (greater than 1 kilogram) mammal species than any other province or state in North America.[9] The southern Okanagan, which has 14 species of bats, is the richest area for bats in Canada.[10]
British Columbia’s fauna are notable not only for high species diversity but also for diversity within species (e.g., subspecies, peripheral populations, island races) and high abundance. Furthermore, some large, remote areas of the province still have intact large mammal predator-prey systems, with various combinations of deer, elk, moose, caribou, mountain sheep, mountain goat, gray wolf, cougar, grizzly bear, black bear and wolverine.[11] Species lost to B.C. include the Queen Charlotte Islands (“Dawson”) caribou, white-tailed jackrabbit, bison (reintroduced) and sea otter (reintroduced).
About 21 species of amphibians occur in B.C., 19 of which are native. Amphibians constitute a surprisingly large percentage of the biomass in the province’s forest ecosystems, particularly in coastal old-growth forests. Centres of richness in B.C. are the south Coast and the dry southern Interior. There are four species of amphibians designated “at risk” in the province: Pacific giant salamander, tiger salamander, Coeur d’Alene salamander and tailed frog.
Five of B.C.’s 15 native species of reptiles are designated “at risk”: sharp-tailed snake, western rattlesnake, gopher snake, short-horned lizard and night snake.[12] This list does not include two species of sea turtles, both of which are seriously endangered. As one would expect, the warm, dry southern Okanagan Valley is the centre of the province’s reptile diversity.
Many of B.C.’s vertebrate species are affected by forest and range management activities. A list of the red-[13] and blue-listed[14] vertebrate species potentially affected by forest and range practices is presented in Appendix A.
Invertebrates constitute the vast majority of kinds of organisms and are very abundant, but they are usually small and difficult to study. About 75% of living things are animals and 75% of these are insects (beetles are one-quarter of all species). Much of our knowledge of B.C.’s invertebrates is in the early phase of taxonomy. The numbers and kinds that occur in B.C. are therefore extremely poorly known. No estimates are possible for rich and ecologically critical groups such as nematodes, flatworms, annelids, molluscs and mites. Around 600 species of spiders (the Canadian total is 1 400) and 35 000 species of insects (the Canadian total is 55 000) occur in B.C. It is likely that about 50% of the insect species in Canada and B.C. are as yet unknown to science.
The richest insect orders in B.C. are true flies (Diptera), beetles (Coleoptera) and wasps, bees and ants (Hymenoptera). Flies increase dramatically in importance with increasing latitude, whereas Hymenoptera tend to increase with aridity.
British Columbia’s insect fauna is more diverse than that of Alberta and is probably more diverse than those of Ontario and Quebec combined. The insect fauna is poorly known, but significant endemism (of both species and subspecies) occurs in those groups that are relatively well known (e.g., endemic subspecies of butterflies in the Peace River area and on the Gulf Islands). The insect fauna of coastal northwestern North America is highly distinctive and has a large endemic component even in areas that were glaciated (e.g., Queen Charlotte Islands, Olympic Peninsula and Vancouver Island).[15] Few other heavily glaciated areas are known to have developed such a distinctive insect fauna with so much endemism.[16] Along with the southwest coast (Strait of Georgia area), the southern Okanagan is the most diverse region in the province. Both areas also contain the largest numbers of threatened and rare insect species.
Microbes
Microscopic organisms include bacteria and viruses (creatures without distinct nuclei in their cells or “prokaryotic”) and protoctists (creatures with distinct nuclei or “eukaryotic”). Bacteria and viruses, though ubiquitous in our environment and vital for processes such as nutrient cycling, are so poorly known taxonomically that we can say nothing about their species diversity.
The kingdom Protoctista comprises eukaryotic micro-organisms and their close descendants and includes flagellates, euglenophytes, amoebae and ciliates, as well as organisms traditionally classed as algae and fungi with flagellated life stages.[17] Protoctists are critical components of all ecosystems, active in organic matter decay and turnover, photosynthesis and other ecological processes. This large, diverse and ubiquitous group is extremely poorly known taxonomically. No estimates of their richness and diversity in B.C. can be made.
2.5.2 Ecosystem Diversity
British Columbia’s diverse climate, topography and soils have produced a province more biologically diverse (in terms of species and ecosystems) than any other in Canada. The province has six of the 10 forest regions of Canada.[18] Though largely forested, it also has extensive grasslands, wetlands and alpine areas.
British Columbia has 14 major climatic, ecological subdivisions, known as biogeoclimatic zones.[19] Each biogeoclimatic zone has numerous habitats, ranging from dry to wet and forested to non-forested.[20] The province has much beta (between-habitat) diversity and very few simple landscapes. Forests predominate, covering more than 55% of the total area, and include deciduous, mixed wood and even some broad-leaved evergreen (in the Strait of Georgia) forest types. In this ruggedly mountainous region with sharp climatic gradients, general diversity increases markedly as area expands, from low to high elevations (tidewater to timberline in many cases) and from west to east. British Columbia boasts a great range of plant communities, from saaniche to muskeg, from coastal temperate rainforest to Great Basin shrub-steppe and dry forest, from tidal and freshwater wetlands to grasslands and alpine tundra.
Biogeoclimatic zones (Figure 2.3) represent areas of broadly homogeneous macroclimate and provide a handy framework for considering the ecological diversity of the province. The biogeoclimatic zones and the ecosystems they contain have been described and mapped over the last 20 years by scientists in the Ministry of Forests Research Program. This ecological classification of the province provides the basis for ecosystem-specific forest management interpretations.[21]
Alpine Tundra
The Alpine Tundra zone, essentially a treeless region characterized by a harsh climate, is found on high mountains throughout the province. The long, cold winters and short, cool growing seasons create conditions too severe for the growth of most woody plants — except in dwarf form. Hence, this zone is dominated by dwarf shrubs, herbs, mosses and lichens. This zone provides important range for caribou, mountain goats and mountain sheep and has high recreational appeal. Due to the severe climate it is extremely sensitive to use. Disturbed landscapes require decades or even centuries to recover to their natural states. The Alpine Tundra zone covers approximately 17.5 million hectares or 18% of B.C.
Spruce–Willow–Birch
This subalpine Spruce–Willow–Birch zone occurs in the severe climate of northern B.C., at elevations above the boreal forest and below the alpine tundra. In its lower parts, the zone is characterized by open forests of primarily white spruce and subalpine fir; upper elevations are dominated by deciduous shrubs, including scrub birch and willow. Cold air collects in some high, wide valleys, resulting in a mosaic of scrub, grassland and wetlands on valley floors below a band of forest on the valley sides. Above, the forest again gives way to shrubs. This zone provides extensive moose, caribou and (in the east) elk habitat. The Spruce–Willow–Birch zone covers approximately 7.8 million ha or 8% of B.C.
Boreal White and Black Spruce
The Boreal White and Black Spruce zone is part of the extensive belt of boreal coniferous forest occurring across Canada. It occupies the northern valleys west of the Rocky Mountains and the gently rolling topography of the Great Plains. Winters are long and cold and the growing season short; the ground remains frozen for much of the year. The severe climate results in forests of low productivity. Numerous fires have created extensive successional forests of trembling aspen and lodgepole pine. Where flat, the landscape is typically a mosaic of black spruce bogs and white spruce and aspen stands. Valuable agricultural land is prevalent in this zone in the Peace River area of the province. Moose and mosquitoes are abundant. The Boreal White and Black Spruce zone covers approximately 15.1 million hectares or 16% of B.C.
Sub-Boreal Pine–Spruce
The Sub-Boreal Pine–Spruce zone occurs on the high plateau of the west central interior in the rainshadow of the Coast Mountains. Due to the cold, dry climate, the forests are generally of low productivity. The landscape is rolling and dotted with numerous wetlands important for wildlife and hay production. The zone is also characterized by many even-aged lodgepole pine stands, the result of an extensive fire history. A minor amount of white spruce regeneration occurs. Lichens and/or feathermosses usually dominate the understorey; pinegrass and kinnikinnick are also common. The profuse ground lichens in the drier parts of the zone provide valuable winter range for caribou. The Sub-Boreal Pine–Spruce zone covers approximately 2.4 million ha or 3% of the province.
Sub-Boreal Spruce
The Sub-Boreal Spruce zone occurs in the central interior of the province, primarily on gently rolling plateaus. The zone is intermediate between the interior Douglas-fir forests to the south and the boreal forests to the north. Forest productivity is moderate and, although the climate is severe, the winters are shorter and the growing season longer than in boreal areas. Hybrid Engelmann-white spruce and subalpine fir are the dominant trees; extensive stands of lodgepole pine occur in the drier portions of the zone due to forest fires. Wetlands are abundant, dotting the landscape in poorly drained areas. Moose are common throughout this zone. The Sub-Boreal Spruce zone covers approximately 9.9 million ha or 10% of B.C.
Mountain Hemlock
The subalpine Mountain Hemlock zone occurs at high elevations along the Pacific coast. The growing season is short, and the annual snowfall is high. Trees are absent where the snowpack remains late in the spring or where the ground freezes under snow. In the upper elevations, forests thin out into open parkland where trees are clumped and interspersed with sedge or mountain-heather communities. At lower elevations, the forest is continuous and more productive. Mountain hemlock and amabilis fir, important commercial species, are the dominant trees; varying amounts of yellow-cedar also occur. Due to the adverse climate, forest regeneration is often slow. The Mountain Hemlock zone covers approximately 4.1 million ha or 4% of B.C.
Engelmann Spruce–Subalpine Fir
The Engelmann Spruce–Subalpine Fir zone occurs at high elevations throughout much of the Interior. The climate is severe, with short, cool growing seasons and long, cold winters. Only those trees capable of tolerating extended periods of frozen ground occur. The landscape at the upper elevations is open parkland, with trees clumped and interspersed with meadow, heath and grassland. Engelmann spruce, subalpine fir and lodgepole pine are the dominant trees. White rhododendron and false azalea are common understorey shrubs. Under drier conditions, extensive lodgepole pine and whitebark pine forests are common. In wetter areas where snowfall is more abundant, mountain hemlock can occur. The Engelmann Spruce–Subalpine Fir zone covers approximately 13.3 million ha or 14% of the province.
Montane Spruce
The Montane Spruce zone occurs in the southcentral Interior at middle elevations and is more extensive on plateau areas. The winters are cold; the summers are moderately short and warm. Engelmann and hybrid spruce and varying amounts of subalpine fir are the characteristic tree species. Due to past wildfires, successional forests of lodgepole pine, Douglas-fir and trembling aspen are common. This zone is intermediate between the Engelmann Spruce–Subalpine Fir zone at higher elevations and the Interior Douglas-fir zone at lower elevations. Forestry activities are extensive through most of this zone. The zone also provides important summer and fall range for mule deer and cattle. The Montane Spruce zone covers approximately 2.6 million ha or 3% of B.C.
Bunchgrass
The Bunchgrass zone is confined to the lower elevations of the driest and hottest valleys of the southern Interior. It supports critical winter and spring forage for bighorn sheep and white-tailed deer and is the home of the burrowing owl. This grassland zone also provides important spring livestock range and, with irrigation, has produced some of the province’s most valuable agricultural land. Bluebunch wheatgrass is the dominant grass on undisturbed sites. At the lower elevations, big sagebrush is common — particularly on overgrazed areas. Ponderosa pine and Douglas-fir occasionally occur in draws and on coarser textured soils, although the dry climate restricts their growth. The Bunchgrass zone covers approximately 300 000 ha or 0.3% of the province.
Ponderosa Pine
The Ponderosa Pine zone — the warmest and driest forest zone — is confined to a narrow band in the driest and warmest valleys of the southern Interior where it often borders the Bunchgrass zone along its lower or drier limits. Ponderosa pine is the dominant tree, and wide spacing, round crowns and yellow-orange bark distinguish this zone. Frequent ground fires are important for creating and maintaining these stands. Douglas-fir is common on the colder and moister sites. Where not overgrazed, the understorey includes abundant grasses such as bluebunch wheatgrass and rough fescue, which provide excellent forage. The Ponderosa Pine zone covers approximately 300 000 ha or 0.3% of B.C.
Interior Douglas-fir
The second warmest forest zone of the dry southern Interior, the Interior Douglas-fir zone occurs in the rainshadow of the Coast, Selkirk and Purcell mountains. Douglas-fir is the dominant tree. Fires have frequently resulted in even-aged lodgepole pine stands at higher elevations, while ponderosa pine is the common seral tree of the lower elevations. Pinegrass and feathermoss dominate the understorey; soopolallie and kinnikinnick are common shrubs. Along its drier limits the zone often becomes savanna-like, supporting bunchgrasses like rough fescue and bluebunch wheatgrass. This zone is important for summer livestock range as well as mule deer and elk habitat. The Interior Douglas-fir zone covers approximately 4.3 million ha or 5% of the province.
Coastal Douglas-fir
In the lee of the Olympic and Vancouver Island mountains, a mild Mediterranean type of climate prevails. Rainshadow coastal forests are dominated by Douglas-fir, with an understorey commonly consisting of salal and/or Oregon grape. Western redcedar is typical of wetter sites, and Garry oak and arbutus are abundant on drier sites. The latter two trees are characteristic of the Coastal Douglas-fir zone and occur nowhere else in Canada. The favorable climate also results in some of the province’s most productive agriculture land. In addition, blue grouse and black-tailed deer habitats are abundant. The Coastal Douglas-fir zone covers approximately 200 000 ha or 0.2% of B.C.
Interior Cedar-Hemlock
The Interior Cedar-Hemlock zone occurs at lower to middle elevations in the interior wet belt of the province. Winters are cool and wet and summers are generally warm and dry. This zone is the most productive in the Interior and has the widest variety of coniferous tree species of any zone in the province. Western hemlock and western redcedar are characteristic species, but spruce (white-Engelmann hybrids) and subalpine fir are common. Douglas-fir and lodgepole pine are generally found on drier sites. Wet sites are often easily recognized by a dense understorey of devil’s club and/or skunk cabbage. The Interior Cedar-Hemlock zone covers approximately 5.0 million ha or 5% of the province.
Coastal Western Hemlock
The northern latitude rainforests composing the Coastal Western Hemlock zone occur at low elevations along the coast. Western hemlock and amabilis fir are the dominant climax trees, although several other species are also common. Abundant rainfall and mild temperatures make these forests the most productive in Canada. In the drier parts of this zone, old-growth Douglas-fir can approach 100 metres in height. On floodplain soils, western redcedar and Sitka spruce can reach up to four metres in diameter. Mature stands of timber within this zone provide important habitat for grizzly bears and black-tailed deer. This zone is sometimes called the “coastal temperate rainforest.” The Coastal Western Hemlock zone covers approximately 10.6 million ha or 11% of B.C.
2.6 Forest Resources
The Ministry of Forests is charged with:
- plan[ning] the use of the forest and range resources of the Crown, so that the production of timber and forage, the harvesting of timber, the grazing of livestock and the realiza-tion of fisheries, wildlife, water, outdoor recreation and other natural resource values are coordinated and integrated….[22]
As the agency responsible for managing approximately 87% of our province’s land base, the Ministry of Forests, with the Ministry of Environment, Lands and Parks and a host of other agencies and individuals, is responsible for planning all types of resource use on that land. For example, although the Ministry of Forests has no mandate to directly manage populations of fish or wildlife (this responsibility rests with the Ministry of Environment, Lands and parks), it is responsible for managing most fish and wildlife habitat in B.C.
There are numerous resources associated with British Columbia’s forests. The 16 values associated with old-growth forests recognized by B.C.’s Old Growth Strategy (Table 2.1) make a good general list of forest resource values.
Timber, range, recreation and botanical forest products are managed by the Ministry of Forests and are discussed in detail in Chapters 3, 4, 5 and 6 of this report. Other forest values — such as tourism, hunting, trapping and fishing — are managed by other agencies (e.g., Ministry of Environment, Lands and Parks).23 Some forest values (e.g., spiritual) are not currently managed by any agency.
