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The Importance of the North Okanagan Grasslands Introduction Some of the public and all levels of government are beginning to understand the importance of biodiversity and are putting words to paper with the intent to improve our country's environmental protection and biodiversity of wildlife and plant life. We know that the Thompson/Okanagan/Nicola and other dry-belt areas of BC are very unique in this province and are very sensitive and vulnerable to ecosystem and habitat destruction. If urban development continues along the same path as in the last few decades, the natural ecosystems and biodiversity of wildlife habitat in these areas will be gone. The goals of provincial and federal governments are to protect 30% of land and water by 2030. This is just a number, if the right areas and connective corridors to maintain biodiversity of species are not considered. If in each ecoregion we protect, preserve and restore the areas of sensitive habitat and the supportive connectivity for wildlife movement and genetic diversity, then we will accomplish our international commitment to preserving Canada’s biodiversity. The Importance The Grasslands of the North Okanagan provide an important wildlife corridor for animals with an opportunity to move freely between two or more habitat patches or habitat types in an otherwise fragmented landscape. This movement is essential to provide genetic links between populations and prevent inbreeding, and to compensate for temporary population declines in one of the habitat patches. Reasons to Protect, Preserve and Restore Biodiversity, species at risk survival, recovery of extirpated species, wildlife connectivity from south to north, maintaining wetlands, gullies, ravines, nesting and denning locations as well as recreational opportunities and preservation of Indigenous cultural history. BC Government Ministry of Environment (published 1998) Habitat Atlas for Wildlife at Risk Preserve Ecosystem Corridors Excerpts from: https://www.env.gov.bc.ca/okanagan/esd/atlas/preserve.html Landscape Linkages For a functional biodiversity strategy, areas of similar terrain should link the core reserves. Landscape linkages should permit movement up and down the Okanagan Valley on both the eastern and western sides. We must also maintain intact elevational landscape connections from low-elevation grasslands, lakes and wetlands up to forests, rugged terrain and subalpine areas. Preserve Grassland Corridors The Okanagan is a critical biological highway to the British Columbia central interior. Originally, the whole of the valley could serve this purpose but the corridor is difficult to maintain with current urban and agricultural land use patterns divided between private, Crown and Indian Reserve ownership. The Okanagan Valley has been a vital landscape corridor and linkage between the grasslands of the intermontane areas and the Great Basin to the south, and the Thompson Valley and Cariboo-Chilcotin grasslands to the north. It still serves as a channel for the movement of plants and animals. It will become even more important as a corridor and landscape linkage with future climate change caused by global warming. Excerpts from: Sensitive Ecosystems Inventory: Vernon Commonage, 2005 https://a100.gov.bc.ca/pub/acat/documents/r4159/wha_4477_rpt_1149095902327_eb94b0d2ace348668725ad272a341dc2.pdf Extensive land development is fragmenting and encroaching on important wildlife habitats, contributing to wildlife and habitat declines. 1.2 Ecological Importance of the Study Area The Okanagan Valley is a region of nearly unparalleled biological diversity within British Columbia, Canada, and North America. The complex terrain of the area, combined with a semi-arid climate moderated by the influence of Lake Okanagan has resulted in a wide diversity of ecosystems and organisms in relatively close proximity to one another. The terrain and presence of glacial-relict lakes distinguish the Okanagan Valley from the broad Columbia Basin to the south. Increasingly, scientists are finding that populations at the edge of their range, such as those in the Okanagan, are likely to persist longer than core populations during population declines. This phenomenon may allow these populations to adapt to future changes such as global warming19. The Okanagan Valley is a north to south corridor that connects the dry interior valleys of British Columbia to southern grassland ecosystems of the Columbia Basin in the U.S. The valley is a corridor for migrating birds and a point of entry for organisms entering into B.C.’s dry interior from the Columbia Basin. The Vernon Commonage was identified in the Vernon Natural Features Inventory as an area that is regionally important for bird life, including a provincially significant year-round concentration of raptors. The area is relatively large and natural, only partly fragmented by roads and development, and has a great diversity of ecosystems, plant and wildlife species, landforms, and bedrock geology. The area received a very high importance ranking in the Natural Features Inventory for rare species and communities. With proper planning and management, the natural features of the study area provide the potential for long-term viability of many endangered species and sensitive ecosystems. The area may be an important area for the northward migration of species during global warming. Finally, the area provides many community values including aesthetics, hiking, and observing wildlife and nature.  Figure 1. Vernon Commonage SEI study area outlined in red.
Landscape connectivity: Disturbed grasslands provide buffers, and connectivity between other ecosystems. Rare vertebrates of disturbed grasslands Swainson's Hawk (R) (Buteo swainsonii) Ferruginous Hawk (R, COSEWIC-SC) (Buteo regalis) Prairie Falcon (R) (Falco mexicanus) Upland Sandpiper (R) (Bartramia longicauda) Burrowing Owl (R, COSEWIC-E) (Athene cunicularia) Grasshopper Sparrow (R) (Ammodramus savannarum) Brewer’s Sparrow (R) (Spizella breweri ssp. breweri) Lark Sparrow (R) (Chondestes grammacus) Preble's Shrew (R) (Sorex preblei) Merriam's Shrew (R) (Sorex merriami) Pallid Bat (R, COSEWIC-T) (Antrozous pallidus) Badger (R, COSEWIC-E) (Taxidea taxus) Great Basin Spadefoot (B, COSEWIC-T) (Spea intermontana) Painted Turtle (B) (Chrysemys picta) Racer (B, COSEWIC-SC) (Coluber constrictor) Gopher Snake (B, COSEWIC-T) (Pituophis catenifer ssp. deserticola) Western Rattlesnake (B, COSEWIC-T) (Crotalus oreganus) Long-billed Curlew (B, COSEWIC-SC) (Numenius americanus) Lewis's Woodpecker (B, COSEWIC-SC) (Melanerpes lewis) Fringed Myotis (B, COSEWIC-SC) (Myotis thysanodes) Western Small-footed Myotis (B) (Myotis ciliolabrum) Great Basin Pocket Mouse (B) (Perognathus parvus) Western Harvest Mouse (B, COSEWIC-SC) (Reithrodontomys megalotis) 16.3 Status Grassland ecosystems cover only 0.8% of British Columbia’s land area and many of these grasslands have been lost or disturbed. The SEI showed that disturbed grasslands covered 24% (1350 ha) of the study area. Although these sites had up to 50% non-native plants, they could provide a source of grassland ecosystems through restoration. In particular, disturbed grassland ecosystems that occur in association with other sensitive and important ecosystems are higher priorities for preservation and restoration. 16.4 Management Recommendations Although 17% of the study area is covered by undisturbed grassland; disturbed grasslands covered a greater proportion. These disturbed grassland ecosystems need to be restored to replace invasive plants with native vegetation. Where disturbed grasslands occur in association with other sensitive ecosystems, they have a higher preservation value and should be a higher priority for Provincially endangered or threatened (R-red-listed) or vulnerable (B-blue-listed) vertebrate species and natural plant communities as of June 2005 are noted. Nationally rare vertebrate species ranked by COSEWIC, as of May 2005, are noted as endangered (E), threatened (T), or of special concern (SC). Grasslands Conservation Council of B.C. 2002 Management recommendations have been adapted from McPhee et al. 2000 and Iverson and Cadrin 2003. Badger populations have declined Badger populations have likely declined from habitat loss, persecution and traffic mortality. Fragmentation of habitats has also likely contributed to their decline. The study area and the Bella Vista – Goose Lake Range are important refuges of expansive grasslands suitable for Badgers. What can we do? Providing adequate habitat and reducing human-caused mortality are the keys to Badger survival in British Columbia. This involves control of urban expansion into grasslands, establishment of protected areas, responsible stewardship of ranges used for cattle grazing and mitigation of highway developments. Conservation of Badger populations in British Columbia cannot be achieved without strong public support. Wildlife Corridors Wildlife corridors provide animals with an opportunity to move freely between two or more habitat patches or habitat types in an otherwise fragmented landscape. This movement is essential to provide genetic links between populations and prevent inbreeding, and to compensate for temporary population declines in one of the habitat patches. The habitat needs of all priority species should be incorporated into the design of the corridor. Corridors must be suitably wide, with appropriate habitat features to provide security cover during movement. Corridors usually consist of linear habitats such as gully or streamside riparian areas; they are often composed of two or more ecosystem types to provide complexity to the corridor. Development and roads should avoid these zones, and mitigation will be required where roads and other developments transect the corridor. Wildlife corridors were identified to connect core areas to each other and to outside the study area, including connections to Okanagan Lake and Kalamalka Lake. In some cases, corridors have already been fragmented by roads and connections need to be restored. In particular, it will be challenging to restore connections across Highway 97. Corridors, where possible, include riparian draws with adjacent warm aspect grasslands, and ridges. These habitat features are those most commonly used for travel between habitats. Larger scale mapping and additional wildlife inventory might identify some small areas that could be developed without compromising connectivity and other corridor values. This would depend upon the type and configuration of development, and site-specific issues. BC Government Farming, natural resources and industry Rangelands Ecology Excerpts from: Rangeland restoration https://www2.gov.bc.ca/gov/content/industry/rangelands/ecology/restoration Ecosystem restoration is the process of assisting with the recovery of an ecosystem that has been degraded, damaged or destroyed by re-establishing its structural characteristics, species composition and ecological processes. In the fire-maintained ecosystems of B.C.’s interior region, a lack of wildfire due to decades of suppression, the absence of prescribed fire and applying no other intervention or disturbance processes as an adequate surrogate for the role of fire, has contributed to trees encroaching onto historic grasslands, as well as excessive in-growth of trees in previously open forests. Hundreds of thousands of hectares have been affected by this ecological change province-wide, causing a reduction of ecosystem resiliency to climate change pressures and a host of negative trends in open forest and grassland ecosystems. Government management of fire maintained ecosystems To partially mitigate these adverse effects on Crown rangelands, the B.C. government is targeting fire-maintained ecosystems. In certain cases it may be necessary to initiate treatment activities on other key ecosystems as well. The expected benefits are ecological, economic, social and cultural. They include:
Extirpated animals Burrowing Owls Excerpts from: https://www.birdatlas.bc.ca/accounts/speciesaccount.jsp?sp=BUOW&lang=en Over the past three decades, the Burrowing Owl population in Canada has declined from an estimate of over 3,000 pairs to fewer than 800 pairs, most of which are in the Prairies ( Environment Canada 2012). British Columbia Species Explorer (British Columbia Ministry of Environment 2014) gives a current British Columbia population estimate of 1-50 birds based on a COSEWIC (2006) estimate of 9 known wild birds. Designated Endangered nationally under the Species at Risk Act, and Red-listed provincially, the Burrowing Owl is also one of only four species to be designated as Endangered under the British Columbia Wildlife Act. https://www2.gov.bc.ca/assets/gov/environment/plants-animals-and-ecosystems/species-ecosystems-at-risk/brochures/burrowing_owl.pdf Over much of its North American range, this owl is most abundant in active colonies of ground squirrels or prairie dogs, where numerous nesting and satellite burrows are available. This indicates that the availability of burrows is a major factor controlling the abundance of Burrowing Owls. Burrows dug by Badgers are also important in many areas. In British Columbia, habitats that are otherwise suitable for this owl have relatively few burrowing mammals. If we save and protect Badgers and their habitat in the Commonage, we can provide the way back for the Burrowing Owl and support the survival of many other species.
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