BIODIVERSITY IN SOUTHERN ALBERTA
Often referred to as “biodiversity”, biological diversity refers to the variety of species and ecosystems and the ecological processes of which they are a part. Three components of biodiversity are ecosystem diversity, species diversity and genetic diversity.
Ecosystem diversity is reflected in the range of large units on the landscape, defined by climate, topography and vegetation, and the biological and physical processes that operate within them. Major ecosystems, or natural regions and subregions, in southern have been defined and mapped by the Alberta Natural Heritage Information Centre (link to http://www.cd.gov.ab.ca/preserving/parks/anhic/natural_regions_map.asp). They include:
Rocky Mountain Natural Region
[include photo of each natural regions/subregions]
Species diversity is the sum of total living organisms, including plants, insects, bacteria, fungi, mites and ticks, crustaceans, fishes, reptiles and amphibians, birds, and mammals. Scientists believe that there are somewhere between 5 and 25 million species on Earth. About 1.5 million species have been recorded to date.
The total number of known species in Canada is around 71,000 and there are about 68,000 other species which are believed to exist, but have not been described. Less than five percent of the nation’s species are thought to be endemic, that is occurring only in Canada and nowhere else.
In Alberta, there are about 2900 plants (vascular and non-vascular) and 450 vertebrate animal species. The precise number of invertebrate (e.g. insects) and fungi species are unknown. Over two-thirds of the province’s species occur in the ecosystems of southern Alberta.
Vertebrate Animal Species in Alberta
Mammals – 84
Birds – 297
Fish – 51
Amphibians – 10
Reptiles – 9
Vascular plants – 1600
Mosses and liverworts - >650
Lichens - >650
[include a photo sample of each group]
The network of species found in each ecosystem is different and unique in the distribution and numbers. Recent research is showing that the productivity and resiliency of ecosystems is related to species richness.
Genetic diversity is the variability at the level of DNA within species. This variability, by conferring resilience and flexibility, is assumed to be responsible for the evolutionary persistence of species. For example, with a reduced genetic base, species like grizzly bears or leopard frogs, are more vulnerable to a new threat such as predation, disease, or environmental change.
LOSS OF BIODIVERSITY
Decline of biodiversity is one of the most serious global environmental threats now facing humanity. Studies of the geological record suggest that extinction is occurring at rates faster than it has ever occurred before. In Canada, since Europeans began arriving in the early 1500s, twenty species or populations are known to have disappeared.
In southern Alberta two species or populations have become extinct – the plains grizzly and greater prairie-chicken – and two species were extirpated, but still occur elsewhere – the black-footed ferret and swift fox. The swift fox has recently been reintroduced.
Forty-five species in southern Alberta are assessed “At Risk” by federal or provincial expert committees. (link to http://www.cosewic.gc.ca/eng/sct0/rpt/dsp_booklet_e.cfm and http://www.srd.gov.ab.ca/fw/speciesatrisk/ ).
Mammals (5 species)
Birds (14 species)
Reptiles (2 species)
eastern yellow-bellied racer
greater short-horned lizard
Amphibians (3 species)
northern leopard frog
great plains toad
Fish (6 species)
Banff longnose dace
western silvery minnow
westslope cutthroad trout
Insect (2 species)
Mollusc (1 species)
Banff Springs snail
Plants (12 species)
small-flowered sand verbena
western blue flag
slender mouse-ear cress
Some of these species occur in the mountains but the majority are species of the plains. In fact, 85% of Alberta’s species at risk are found in the Grassland and Parkland natural regions. Loss of suitable habitat is the biggest contributing factor. Only 26% of the Grassland and Parkland natural regions remain in a relatively natural state; and, there are increasing demands on the remnants of native habitat from human activities such as agricultural expansion, oil and gas development, urban residential development, recreation and rural subdivision. In the Rocky Mountain Natural Region loss of suitable habitat is attributed to many of these same factors as well as clearcut logging. Other factors which contribute to species risk and loss of biodiversity are overharvesting, introduction of alien species, pesticides, disease and isolation.
Protecting biodiversity – ecosystems, species and genetics – requires good science and the belief among southern Albertans that it is the right thing to do. It requires leadership by governments to put in place appropriate legislation, policy and programs. It requires cooperation among a variety of interests.
There are many initiatives underway in southern Alberta to protect biodiversity.
Parks and other designated protected areas
Private conservancy (conservation easements)
Programs to improve range, riparian and aquatic health
Species at risk assessment, designation and recovery plans
Land use planning by communities interested in conservation
Much more still needs to be done.