165 I

WILDLIFE HABITAT MITIGATION FOR THE OLDMAN DAM PROJECT, , CANADA1

IL. by

[ Jeffrey E. Green, P. Biol.2 [ and Alan Nilson, P. Eng.3

Abstract. To compensate for losses of wildlife habitat associated with [ the construction and operation of the in , an extensive wildlife habitat mitigation program has been undertaken. Habitat evaluation procedures were used to determine the amount and types of habitat losses in the reservoir area, and the most [' important habitat needs of wildlife in the mitigation program. Three major types of mitigation, involving thirteen specific measures, are being employed in the Mitigation Program: habitat protection, habitat enhancement and habitat creation. A concept plan was developed that [ addressed the biological requirements of wildlife (e.g., movement corridors, core habitat areas and other specialized sites) in conjunction with existing land uses, the need for a good distribution of projects [ around the reservoir, and the suitability for establishment of woody vegetation. In total, 65 habitat projects are being developed, as well as additional projects for cliff nesting raptors. Other habitat enhancement and creation projects may be developed as opportunities artse durtng dam l construction and reclamation. Additional Key Words: habitat reclamation, mule deer, waterfowl [

Introduction

Paper presented at the conference, The Oldman River Dam is currently being Reclamation, A Global Perspective, held in constructed a short distance downstream from the Calgary, Alberta, , August 27-31, 1989. confluence of the Oldman, Crowsnest and Castle in southern Alberta. When completed in 2 Jeffrey E. Green is a Principal and Senior 1990, the dam will create a reservoir covering an Biologist for The Delta Environmental area of approximately 2420 ha at full supply level L Management Group Ltd., Suite 101, 622 - 5th (FSL). Figure 1 shows the location of the Avenue S.W., Calgary, Alberta T2P OMS . reservoir.

3 Alan Nilson is the Program Manager of Wildlife Although cultivated fields, pastureland, l., Mitigation, Alberta Public Works, Supply and winter feedlots and farmsteads occupy most of the Services.5th Floor, College Plaza , 8215 - 112 bottomland areas in these valleys, the remaining - ,- Street, Edmonton, Alberta T6G SAG. valley areas and adjacent are important L_, overwintering habitats for wildlife. For example, approximately 350-400 mule deer ( Odocoileus hemionus) overwintered in and around the

L Rg. I Rg.llO Rg ... 4

,..._.

Tp7 .... °'

OLDMAN RIVER DAM SITE

SCALE I 1 100 000

TOP OF DAM ELEVATION 3680 FT. (1121.7ml PROJECT LOCATION F.S.L.3670 FT. ( 1118.6 m l

Figure 1. General location of the study area for the Oldman River Wildlife Habitat Mitigation Plan in southeastern Alberta, Canada. ,~ ~ ~~ ~~ ·~ 167

reservoir area during 1985-86, with slightly more Habitat Mitigation Projects than half that number being present during the spring and summer months {Allison and Russell The wildlife habitat mitigation program 1986). The reservoir area also supports a variety involves three major classes of mitigation of other mammals and avifauna on a seasonal or methods: habitat protection, habitat year-round basis including white-tailed deer { 0. enhancement and habitat creation. virginianus), moose {uncommon} {A/ces atces), yellow-bellied marmots (Marmota f/aviventris), badgers {Taxidea taxus), beaver {Castor Habitat Protection Measures canadensis), mink (Mustafa vison), Ferruginous hawks {Buteo regalis), prairie falcons {Falco Two initiatives have been undertaken to mexicanus), Canada geese {Branta canadensis), complete the habitat protection phase of the mallards {Anas platyrhyncos), and common wildlife habitat mitigation program. A land base of mergansers {Branta merganser) (Young et al. approximately 700 hectares (2300 acres} has 1986). been secured from crown lands for use in the [ wildlife habitat mitigation program. An additional Because of the importance of the flooded 50 ha of private land may be secured through area to wildlife, Alberta Public Works, the Alberta easements, leases or purchase agreements to [ Fish and Wildlife Division and Alberta Environment complete the wildlife mitigation program. have undertaken a program to enhance existing habitat conditions around the proposed reservoir. 1. Vegetation clearing guidelines have been The Delta Environmental Management Group Ltd. established to retain as much habitat as [ (The Delta Group) was retained to develop possible. These include: practical, effective habitat improvement and creation projects which could be implemented in staging the clearing of the reservoir over the vicinity of the reservoir area during 1988 to 1989 and 1990 to delay disturbance of [ 1993 {Green and Eccles 1988; Nilson and Green wildlife cover as long as possible; 1988). Recent studies. on wildlife numbers, distributions and habitat preferences in the vicinity retaining most shrubs of less than 3 [ of the Oldman River Dam (Allison and Russell metres in height within the flood zone of 1985, 1986; Westworth 1984; Young et al. 1986), the reservoir; as well as information from the Alberta Fish and Wildlife Division, the Local Advisory Committee, preserving stands of black (Popu/us [ and field surveys, aided in the selection and trichocarpa) and narrow leaf {Populus design of appropriate projects for the area. angustifolia) cottonwood and flood tolerant shrubs in those areas of the The major objectives of the Wildlife Habitat reservoir where only shallow flooding (i.e., [ Mitigation Plan, as described by Alberta <2 m} of short duration (e.g., <5 weeks} is Environment (1988) are: expected to occur during the normal operation of the reservoir, or where soil 1. To minimize the potential negative impacts of erosion will not threaten moderate to long- L the Oldman River dam project on wildlife term (>25 years} survival of trees and species, and shrubs. This also includes leaving selected stands of vegetation within the 2. To take advantage of mitigation opportunities borrow areas downstream of the dam. L arising from the development of the dam and reservoir. • minimizing the clearing of Douglas Fir (Pseudotsuga menziesi1) and trembling This paper describes the major measures aspen { Populus tremuloides) communities L which will be implemented as part of the Wildlife in the area between the full supply level Habitat Mitigation Plan with emphasis on specific and the reservoir takeline; and wildlife considerations relating to the water level [ fluctuations of the Oldman River Dam Reservoir. 2. All of the land base for wildlife will be fenced to permit management of grazing and other land uses utilizing a 3-wire fence with posts at [_ 5 metre spacing. Fencing of the wildlife mitigation land base will add 7 km of fence to the 118 km fence that is required for the L reservoir boundary. 168

supplemental water supplies during periods A range management program will be of poor water availability), construction of developed for suitable areas of native and earthen or rock nesting islands in the central improved pasture that occur within the deep water areas of wetlands, enlargement of fenced boundaries of wildlife habitat the wetland basin, planting of riparian shrubs mitigation projects. Range management and trees along some portions of the wetland plans will identify acceptable standards for shoreline, reseeding of nesting cover in cattle use (e.g., the number of animal use adjacent upland areas, and/or maintenance of days, timing and duration of use}, and existing nesting cover. recommend rest-rotational grazing schemes (e.g., location of water sources, additional 3. Nine nesting sites for Canada geese will be fencing as necessary) to permit cattle use constructed on several outcroppings that are without detrimental effects to wildlife habitat. likely to become large islands within the Gravelled water access will be provided to reservoir. Nest sites will include one or more most check dams in the vicinity of existing log nest cribs and, in some cases, may private or crown owned pasture lands. include planting of small shelterbelts and erection of snowfencing. Operation and maintenance of this portion of the program is limited to the maintenance of the 4. Native and improved range in several areas fence and the administration of the grazing permit within the takeline is. in poor condition or has system. been removed by cultivation. These areas will be reseeded with native or suitable commercially-available grasses to provide a Habitat Enhancement Measures stable grass cover for control of noxious weeds and soil erosion, as well as forage for Habitat enhancement projects involve the wildlife and cattle. Some pasture areas will be improvement and/or expansion of existing sites fertilized to promote rapid regeneration of and natural habitats to provide more suitable ground vegetation. and/or larger areas of habitat for terrestrial and wetland wildlife than presently exists. Habitat All of the enhancement projects are within enhancement includes: the fenceline provided for the habitat protection measures. Although short term maintenance will 1 . A total of 25 km of snowfence will be installed be required for establishment of aquatic and along the perimeter fence and/or within the riparian vegetation in enhanced wetlands, tree land base of 31 projects. Snowfencing will and shrub establishment for nesting cribs, and locally improve soil moisture conditions (as a range reseeding programs, no moderate or long result of increased snow retention) and term maintenance (i.e., >5 years) of these projects reduce exposure to wind. It will also will be required. However, a process for encourage the expansion of native trees and administration and management of grazing permits shrubs up and out of the existing coulees, within the wildlife mitigation areas will be and aid in the establishment of planted implemented. shelterbelts. Irregularly-shaped shelterbelts comprised of upland species of trees and shrubs such as trembling aspen, chokecherry Habitat creation (Prunus virginianus), saskatoon (Amelanchier alnifo/ia), hawthorn ( Crataegus rotundifolia) Habitat creation projects involve the and Douglas fir will be planted immediately construction or significant modification of existing adjacent to the leeward side of the sites to provide habitats with significantly different snowfencing in almost all projects. As native biological and physical conditions than existed tree and shrub communities expand and the previously. Habitat creation project will include: planted shelterbelts become established, snow catchment will increase, thereby 1. The accumulation and storage of water in reducing the future need for snowfencing. check dams and newly-created wetlands, and As a result, long-term maintenance of the distribution of water in the areas where snowfencing will not be required. soil moisture conditions may limit the initial establishment of tree and shrub cover. The 2. Five existing wetland areas will be enhanced accumulation and storage of water and the for waterfowl through stabilization of water ability to provide water to the newly-planted levels (including the provision of seedlings on a frequent basis is essential to 169

the successfully establishment of new tree replace some of the bottomland habitats that and shrub cover in exposed upland areas. will be lost to flooding, and will provide several core habitat areas. [ Water storage structures will range from dugouts with shallow catchment basins to 3. Fifteen new nesting cavities for prairie falcons small (<7 m in height) dams in several and Ferruginous hawks have been coulees. In areas where sufficient natural constructed on cliffs above the full supply [ runoff exists to provide a two year supply of level of the reservoir or on cliffs adjacent to water, no ancillary measures are necessary. the reservoir edge (i.e., up to 2.0 km away Where the natural runoff is insufficient, from the reservoir) using controlled blasting, supplementary water will be provided by manual digging and prying. New nesting shelterbelts to improve and/or concentrate ledges for Canada geese have also been snow catchment, subsurface drainage to constructed on cliffs directly adjacent to the capture artesian springs, and pumping of reservoir. Although constructed in January water from the Oldman reservoir using 1989, two nesting cavities are already being electric, solar or wind powered systems. used by prairie falcons and several ledges have been used by Canada geese and great Stored water will primarily be used to water horned owls. tree and shrub seedlings that are located downstream of the check dams and dugouts, 4. On the request of the local wildlife advisory using subsurface irrigation tubing with slow sub-committee, two marmot colonies that are release emitters. Methods are currently being presently located in the reservoir area will be [ investigated to automate the operation of transplanted to new locations above full these irrigation systems. Water levels in the supply level. In one case, a rock pile will be check dams and dugouts will fluctuate constructed adjacent to suitable foraging seasonally in response to snowmelt and habitat to provide a suitable core area for [ rainfall, evaporation, water removal for burrows and loafing/observation sites. watering of trees and -shrubs, and livestock use. In two locations, check dams will be In general, new habitat projects will be the [ used to maintain stable water levels in newly- most difficult to establish and most will require an created wetland basins. Riparian shrubs and operations and maintenance commitment. The emergent aquatic vegetation will be planted proposed check dams and dugouts will require along the perimeter of most check dams and annual inspection and maintenance to ensure [ dugouts to provide vegetation cover and their serviceability, stability and safety. Although food for terrestrial and wetland wildlife. Thirty- the subsurface irrigation systems will be one (31) check dams and dugouts are automated, routine inspections will be required to proposed. ensure operation. It is anticipated that all irrigation r· systems will be operated for a minimum of 5 years 2. New riparian habitat will be provided through to allow trees and shrubs to become well the construction of terraces and/or dikes established, thereby creating a micro-climate that within the upper flood zone of the reservoir is self-sustaining. Operations manuals and spare l (i.e., up to 3 m below full supply level). parts will be provided for the operations personnel Riparian wetlands will be constructed at 23 to operate, maintain and inspect these mechanical locations. These sites will backflood when systems at appropriate intervals. the reservoir is brought to full supply level,· L and hold water 0.6 m below the full supply level of the reservoir when it is lowered. Where appropriate, nesting islands for Implementation Schedule [ waterfowl and Canada geese will be constructed in these wetlands. Narrow leaf Completion of the wildlife mitigation program cottonwood, sandbar willow (Salix exigua), will be constrained by several project activities sedges ( Carex sp.) and aquatic plants will be including: [ planted in the area immediately at and below full supply level. Riparian trees and shrubs the filling schedule for the reservoir, such as black cottonwood, sandbar willow, red osier dogwood ( Cornus stolonifera) and attainment of a full operational level for the l white spruce (Picea glauca) will be planted in reservoir, and the areas immediately above full supply level. The proposed riparian wetland projects will propagation of native tree and shrub stock. I_ 170

implementation to ensure the success, or the However, as the land base has already been need for modification, of specific mitigation secured for the wildlife habitat mitigation program, techniques. most aspects of the mitigation projects involving construction of facilities, excavation, recontouring, The monitoring program will consist of three and fencing can be completed during the 1987 - major components: 1989 period. 1. Assessments of Vegetation: Vegetation Plantings of trees and shrubs will primarily monitoring will include annual assessments of utilize native species from the Oldman River the survival of tree and shrub seedlings, region. To provide stock that is already surveys of ground covers in newly-seeded conditioned to the biophysical conditions in the and/or fertilized pasture areas, inspections of Oldman River area, cuttings and seeds of trees transplanted and naturally invading aquatic and shrubs were collected during the spring and vegetation in enhanced and newly-created. summer 1988 and 1989 for propagation of wetlands and check dams, and range surveys containerized seedlings, bare root seedlings and in rest-rotational pasture areas. Vegetation cuttings. Species being grown include Douglas monitoring will provide information on the fir, limber pine, trembling aspen, black establishment and response of native cottonwood, narrow leaf cottonwood, vegetation in the habitat projects and, in chokecherry, sandbar willow, saskatoon, particular, will highlight the need for hawthorn, red osier dogwood, buckbrush supplemental or replacement plantings of (Symphoricarpos occidentalis), snowberry (S. seedlings, ground covers and aquatic plants. a/bus), and cinquefoil (Potentil/a fruticosa). Most of these species will be available for planting in 2. Assessments of Wildlife Distribution and 1990 and 1991. Habitat lJ se: The wildlife monitoring component will require assessment of the As the full supply level of the reservoir may response of wildlife to (i) the dam not be achieved during ·the first year of operation construction and clearing activities, and (ii) (1991), the riparian marshes may not be the habitat mitigation projects. backflooded from the reservoir until full supply level is attained. As a result, water may need to be Assessment of the responses of wildlife to provided and maintained by pumping water from the dam construction and clearing activities the rivers or reservoir. Provision of water in these will require monitoring of changes in the areas will permit the planting and establishment of abundance and distribution of several riparian trees and shrubs and aquatic vegetation in species and/or groups of wildlife that are and around the perimeter of these riparian representative of the habitat requirements of wetlands, prior to full operation of the reservoir. most wildlife in the Oldman River region. Recommended key wildlife species/groups Several activities will be ongoing after 1991, include: mule deer, waterfowl, raptors, and including: songbirds. Proposed surveys include:

• Planting of remaining tree and shrub systematic surveys of mule· deer seedlings (predominantly those species that populations in the vicinity of the Oldman were not ready for planting in 1991). River (in the vicinity of the project area) Maintenance of vegetation will continue until and in existing wetlands near the trees, shrubs and ground covers are well reservoir. Proposed surveys include an established. early spring breeding survey, brood Reclamation activities in borrow sites and counts, and a fall staging survey. construction areas will continue as necessary. Remedial measures to specific mitigation • annual surveys of nesting and non- projects or project components to ensure breeding prairie falcons, Ferruginous adequate wildlife habitat is established. hawks and other raptors in the Oldman Project area. Data will also be obtained on the nesting success of prairie falcons and Ferruginous hawks in the immediate Monitoring and Evaluation vicinity of the reservoir. Nesting prairie falcons have been colour banded to Physical, biological and botanical aspects of permit tracking of nesting pairs during and the program will be monitored after 171

following dam construction, and the modification of nesting cliffs for these annual inspections of barbed-wired species. fencing and snowfencing, r breeding birds counts for song birds and seasonal inspections of rest-rotational upland game birds in the reservoir area. pastures to assess range productivity, and Permanent survey blocks will be to ensure compliance with the range [ established in representative vegetation management plan, and communities. annual assessment of habitat suitability in Baseline data are available for ungulates and representative habitat projects. [ raptors from wildlife surveys conducted in Quantification of habitat suitability will 1985 - 1986. Systematic surveys during dam require measurement of vegetation construction will be conducted in mid-winter features, terrain features, and physical 1989-90 and 1990-91. Post-flooding structures (data from the vegetation surveys will then be conducted, at minimum, monitoring and wildlife monitoring on a biennial basis. programs can be used to assist in assessment of habitat suitability), and use [ Monitoring of the responses of wildlife to the of field data in computerized habitat mitigation projects will involve annual and assessment models .. biannual assessments of the use of representative habitat projects by key Project audits will allow early identification and [ species and groups of wildlife. Although data correction of project deficiencies or problems, as from the surveys described above will be well as the potential to identify other habitat used, information will also be obtained on the enhancement or creation opportunities. use of tree and shrub plantings by ungulates [ (e.g., browse surveys, pellet group counts), and wetland use by waterfowl. The Glass Project [ 3. Audits of Habitat Projects: Habitat designs for specific projects will generally involve Prior to the completion of the Wildlife Habitat hydraulic structures (e.g., check dams, Mitigation Plan, a comprehensive wildlife subsurface irrigation systems), physical development program was initiated on a 200 ha [ structures (e.g., perimeter fencing, parcel of land immediately adjacent to the dam snowfencing), vegetation components, construction site. Referred to as the Glass and/or specialized habitat structures (e.g., Property, it is comprised of approximately 150 ha nest cribs, nesting ledges, nesting islands, of previously cultivated land and 50 ha of native [ rock piles). In combination, these project pasture. As a result of recent poor land components should provide specific types of management, 120 ha of the cultivated land has habitat for terrestrial and/or wetland- been subjected to extensive wind erosion. A associated wildlife. series of well-established shelterbelts, running [ east-west and north-south, divide the northern Audits of habitat projects will be used to third of the area into four distinct blocks. Two determine if the habitat objectives of specific major systems occur in the southern third projects are being achieved, and that specific of the property. Three natural wetland project components are performing as depressions are located in the west-central portion planned. Project audits will involve a of the property, but because of the extended combination of one or more of the following, drought in the Oldman region, have been depending on the complexity and scope of completely dry for at least the past two years. L the habitat project: Due to the proximity to the dam, the land will • annual inspections of check dams and be permanently held by the Crown. Because of L dugouts to assess water retention the land tenure, the need to restabilize eroding capabilities, soils, and the existence of natural wetland basins and coulees, the Glass Property provided an annual inspection of subsurface irrigation excellent opportunity to integrate and test several systems to ensure that adequate water is wildlife habitat mitigation measures. being provided to tree and shrub seedings, 172

Water was considered to be the limiting factor 8 m. A total of 27,000 seedlings have been in the initial establishment of tree and shrub cover planted to date. Of this total, approximately on the property. Based on the previous 17,000 seedlings will be moved to other sites experience of local landowners in establishing around the reservoir (on an as-need basis). Native shelterbelts in similar exposed sites, it is essential trees and shrubs will then be used to infill-plant in that young trees and shrubs receive adequate some locations on the Glass Property. moisture for a period of at least 3 to 5 years. Although tree and shrub plantings on the Glass The Glass Property contains two natural Property were located on north-facing slopes, wetlands, and two additional wetlands have been protected coulees and the lee side of snow constructed in shallow depresssions. Bulrushes fences whenever possible, direct watering of (Scirpus sp.) were transplanted as plugs from the seedlings by subsurface emitter irrigation tubing reservoir area to one of the constructed wetlands was employed throughout most of the planting to determine the success of this method. All four areas. Subsurface irrtgation was chosen over truck wetlands are now being filled from the pumping watering because it is more cost effective, allows system, but the option exists to fill the wetlands, as seedlings on slopes, can be fully automated in required, by gravity from the reservoir. Snow most circumstances, and in light of its lower entrapment by the snowfences and trees/shrubs operating cost, it is less susceptible to budget will also provide a water source in the spring. restrictions over the long term. Earthen islands for waterfowl nesting have now been constructed in two of the wetlands (one Construction of the prototype irrigation natural, one constructed). system began in fall 1987 and was completed in summer 1988. The system is comprised of a 15 The entire site was planted with a mix of HP electric pump to deliver water through an 8 cm agronomic grasses and legumes under a winter diameter PVC pipe to a central control system on wheat cover during fall 1988 to reduce soil erosion the Glass Project, and a network of water lines, and control weed cover. The mix is comprised of control valves and 20 km of subsurface emitter rough fescue (Fescue scabrella), sheep fescue (F. tubing to provide a maximum of 0.5 - 2.0 gal/hr to ovina). western wheatgrass (Agropyron smifhi1), each individual or pair of tree and shrub seedlings. streambank wheatgrass (A. riparium). alfalfa The central control system is a mechanical timer (Medicago sp.). and sweet clover (Me/ilotus alba). that operates the control valves on specific water lines, and permits specific units of the irrigation Snowfencing has been used extensively (4.0 system to be turned off and on in specific km in total) on the Glass Property to reduce the sequences over a 24 hour period. The exact drying effects of wind on young seedlings, and to duration and sequence of watering will be aid in the trapping of snow to improve soil moisture determined through trial operation in late June - conditions in the spring and early summer. As the early September 1989 and 1990. In other trees and shrubs become better established, they mitigation projects, a combination of emitter will further improve snow retention. irrigation tubing and check dams will be used to provide an initial water source for seedlings." The Glass Property is currently used by mule deer and waterfowl. The Glass Property is presently planted with commercial tree species: Northwest poplar, ca rag an a ( Caragana arborescens), blue spruce (Picea pungens), white spruce and willow. In Literature Cited addition, small native Douglas firs were moved from within the reservoir area to the Glass site to Allison, L.M. and H.J. Russell. 1985. Late winter determine their success at transplanting and distribution of cervids in the vicinity of the growing in a different aspect. Tree and shrub proposed Oldman River reservoir 1985. seedlings have been and will be planted in Prepared by Salix Enterprises Ltd. for Alberta different configurations (contour plantings, Environment, Planning Division, Edmonton. straight rows, irregular groupings) to provide a 63 pp. diversity of cover and to assess the wind revetment characteristics of snowfencing (which Allison, L.M. and H.J. Russell. 1986. Winter has been erected close to most of the planting studies of cervids in the valleys of the Oldman areas). The caragana and willow seedlings were River and its tributaries 1985-86. Prepared spaced at 1 m, the Northwest poplar at 2 m and the by Salix Enterprises Ltd. for Alberta blue spruce, white spruce and Douglas fir at 3 m. Environment, Planning Division, Edmonton. Rows of seedlings were generally spaced at 4 m or 53 pp. 173

Green, J.E. and T.R. Eccles. 1988. A strategy for Westworth, D.A. and L.N. Brusnyk. 1985. Phase I wildlife mitigation for the Oldman River dam overview for the Oldman River Dam reservoir. Prepared for the Oldman River environmental mitigation/opportunity plan. Project Office, Alberta Public Works, Prepared for Alberta Environment by D.A. Supplies and Services by The Delta Westworth and Associates Ltd. 64 pp. Environmental Management Group Ltd. 38 pp. U.S.F.W.S. 1980. Habitat evaluation procedures r (HEP) ESM 102. Prepared by Division of Hardy Associates (1978) Ltd. 1986. Vegetation Ecological Services, U.S. Fish and Wildlife inventory: Oldman River Dam. Prepared for Service, Washington, D.C. n.p. [ Alberta Environment, Planning Division, Edmonton. 73 pp. + Appendices and Map Young, D.A, D.A. Weidl, L.M. Allison and H.J. pocket. Russell. 1986. Oldman River Dam Wildlife Investigations - spring and summer, 1985. Nilson, A.L. and J.E. Green. 1989. An action plan Prepared by Environmental Management for wildlife habitat mitigation for the Oldman Associates and Salix Enterprises Ltd. for River Dam Reservoir. Prepared by the Alberta Environment, Planning Division. Oldman River Project Office, Alberta Public Edmonton, Alberta. 91 pp. + Appendices. [ Works, Supply and Services. 16 pp. [ [ [ [ [ [ L L L

I ! 174