Ian Robertson Robertson Environmental Services Ltd th Street Langley, B.C. V2Z 1 W5

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1 Volume 9,1999 British Columbia Birds Page 3 SURVEYS OF WATER-ASSOCIATED BIRDS ON THE PEACE RIVER DOWNSTREAM OF THE W. A. C. BENNETT DAM Ian Robertson Robertson Environmental Services Ltd th Street Langley, B.C. V2Z 1 W5 Abstract -- Systematic aerial surveys for aquatic birds were conducted in February 1996 and August 1999 with supplemental ground surveys in 1999 to determine species composition, habitat use, and the potential role of river regulation on use pattems following changes in flow of the Peace River by the W. A. C. Bennett Dam since Winter surveys indicated that open water, restricted to the river mainstem, attracted a small population of water-associated birds and raptors. Approximately 84% of the 366 birds observed were Common Mergansers, 45% of which were concentrated within 3 km. of the dam. Nineteen (63%) of the 3 1 Bald Eagles recorded in this survey were also recorded here. The late August surveys coincided with the late breeding season of most of the river-using species expected in this area, the waterfowl moulting period, and the early and middle phases of post-breeding dispersal and fall migration. Twenty-six species were recorded, 20 of water birds and six of raptors. Of the total of 3,482 individuals recorded during aerial surveys, 5 1% were Canada Geese (905) and Mallards (885). Gulls comprised 24% and other fairly common species were Green-winged Teal (240) and Spotted Sandpipers (154). Bald Eagles (25) were by far the most common raptors observed. While birds were distributed along the entire length of the river, 60% of the birds were observed between Cache Creek and the Pine River (27% of the linear area). The major concentrations of geese, dabbling ducks and gulls in this area may have been influenced by the proximity of Fort St. John and food sources associated with its garbage dump, sewage lagoons, agriculture, and grain processing industry. While most species occurred in greatest numbers in non-mainstem (oxbow, back channel) habitats, certain numerous species (Canada Geese, gull sp.) and characteristic riverine species (Common Merganser, Spotted Sandpiper) were found predominantly in or beside the river mainstem. Open water conditions provide increased winter habitat for Common Mergansers, their winter numbers being seven times that of late summer. Regular water level fluctuations, though small, appear to have a greater potential effect on non-mainstem compared to mainstem habitats. These quiescent, unscoured backchannel habitats, internally regulated in many areas by beaver dams, provide in the short term a productive and stable environment for waterfowl. Key wordr;: Bald Eagle, Common Merganser, dam effects, Haliaeetus leucocephalus, Mergus merganser, Peace River, waterfowl. Since flows have been regulated on the Peace River via the W. A. C. Bennett Dam starting in 1967, river discharge pattems downstream have changed substantially. Regulated flows reduced the freshet, and seasonal discharge became relatively uniform with regular fluctuations reflecting the contribution of downstream tributaries. In winter, an extensive area of open water now extends downstream from the W. A. C. Bennett Dam at least as far as Taylor, B.C. Interest in the aquatic avifauna was triggered by the limited information on this community, and specifically by two phenomena. The fxst was the newly available open water in winter and the possibility that this had created habitat, and second was the vulnerability of poorly documented floodplain birds which might be affected by short-term river fluctuations associated with power generation demands. These led to two survey programs: in February 1996 and August The August 1999 surveys, while focused on a broad array of wildlife, included an emphasis on shorebird use of floodplain habitats, and this in part influenced study timing. These programs were documented in two technical reports to B. C. Hydro (Robertson et ; Robertson and Hawkes 2000). This paper summarizes the main findings from these reports as part of a series on the wildlife use of hydro-altered habitats in British Columbia. STUDY AREA Downstream of the W. A. C. Bennett Dam, the Peace River can be defined by one reservoir and seven downstream reaches (Figure 1). The 1996 program included the run-of-the-river reservoir (Dinosaur Reservoir) between the W. A. C. Bennett Dam and the Peace Canyon Dam. The 1999 program did not. The downstream reaches are separated by the confluences with key tributaries, and these were used to segregate survey results. Structurally the river at cross-sections is relatively complex. The river mainstem describes where the bulk of the river flow is located and where most of the river's energy resides. Its banks and substrate, a combination of boulders, cobbles and relatively coarse sand, reflect this high energy environment. The river

2 Page 4 British Columbia Birds Volume 9,1999 Figure 1: The Peace River showing the eight reaches used to stratib data collection during water-associated bird surveys in February 1996 and August cross-section in many parts of the Peace River also includes back channels, as well as separate wetlands and oxbows. The latter are flooded (i.e., directly connected to the river) at varying frequencies, depending on river stage. These distinctions represent separate aquatic habitats that influence the distribution of aquatic birds. STUDY METHODS Survey information was derived from both aerial and ground surveys. The design of the aerial survey component followed the discussion of suitable approaches recommended initially by the B. C. Resources Inventory Committee (Beasley 1995) and revised in final form in 1999 (Resources Inventory Committee 1999). Surveys were conducted from a helicopter (Bell 206 Jet Ranger), which is superior for accuracy compared to fix-wing aircraft, and has several other important capabilities: slower speed, greater maneuverability, superior visibility, and variable flight heights (Resources Inventory Committee 1999). Since our goal was to survey all the floodplain wetlands, and in August 1999 several of these comprised groups of parallel wetlands across a given river cross-section, a maneuverable aircraft was a necessity. Further, we frequently broke off our linear flight line to circle a concentration of aquatic birds. This allowed the observers to estimate numbers better and determine species composition more accurately. Conditions during both aerial surveys were favourable, with negligible winds, and temperatures varying from -3' C. to +3' C. on 15 February 1996, and 16' C. to 22' C. on 20 August Observers (two) were seated in the fiont left and rear left of the helicopter, observing birds with the naked eye, occasionally assisted with 9 x 35 binoculars. Information recorded on tape comprised time, location, species or species group, numbers, and habitat. For certain species, such as Bald Eagles (Haliaeetus leucocephalus), we differentiated between adult and juvenile plumages. Birds observed were also recorded as either swimming, flying, standing on shore or on the ice, or perching. Though we were prepared to record feeding behaviour, the presence of the helicopter probably interrupted this activity, and we obtained no reliable results.

3 Volume British Columbia Birds Page 5 Though local conditions required some variance in the survey protocol from time to time, the following survey regimen was followed in both 1996 and 1999: survey height was 50 m. survey speed was 120 km./hr. (65 knots). survey track was 50 m. from shore, except to cover back channels, oxbows and floodplain wetlands. i) the Peace River Canyon below the W. A. C. Bennett Dam (Reach 8), where there were three substantial flocks of Common Mergansers (Mergus merganser) amounting to an estimated 140 individuals, and two groups of Bald Eagles totalling an estimated 19 individuals; ii) Reach 7, particularly the downstream portion between the Peace Canyon Dam and Hudson's Hope. Surveys covered the same route in both 1996 and 1999 except that the Dinosaur Reservoir was covered only in The survey started at the confluence of the Moberly and Peace rivers, and from there proceeded westward to the upstream terminus (W.A.C. Bennett Dam in 1996; Peace Canyon Dam in 1999). From there it continued downstream to the Alberta border, then returned westward to the starting location. River conditions between surveys were different in one major respect: in February 1996 only the river mainstem was ice-free, eliminating the need to cover non-mainstem habitats. In August 1999, ground and boat surveys were used to gather further information on aquatic birds and raptors of the Peace River floodplain. These comprised 27 transects at eight separate survey locations on or adjacent to the Peace River between 21 and 24 August FEBRUARY 1996 SURVEY Abundance and Distribution In total, 366 water-associated birds were observed on the Peace River between the W. A. C. Bennett Dam and the A1bertaB.C. border (Table 1). The greatest concentrations were recorded in the following locations: Numbers in these two areas amounted to 258 of the 366 birds observed. Species Composition Five species were observed during our surveys, plus "unidentified diving ducks" (Table 1). Common Merganser was by far the most numerous of the species observed, representing 83.6% of all birds (Table 1). The second most numerous species, Bald Eagle, represented 8.5% of the birds observed. Bald Eagles are conspicuous and, as such are hard to miss; on the other hand, our search patterns were directed primarily at the open water and some eagles perched beside the river and at the height of our aircraft could have been missed. A small number of Common Goldeneyes (Bucephala clangula) and Mallards (Anus plaprhynchos) were observed, plus one American Dipper (Cinch mexicanus). The additional sightings of unidentified diving ducks were probably female goldeneyes, female mergansers, or possibly grebes. Not all wintering waterfowl concentrate on the river. John Elliott (B.C. Ministry of Water, Land and Air Protection, Fort St. John, personal communication) pointed out that Canada Geese (Branta canadensis) winter in the area. They were reported in winter 1996 in the Lynx Creek area, and during most winters are TABLE 1 WATER-ASSOCIATED BIRDS OBSERVED ON REACHES OF THE PEACE RIVER FROM THE ALBERTM3.C. BORDER UPSTREAM TO THE W. A. C. BENNETT DAM, 15 FEBRUARY 1996 COMMON COMMON UNIDENTIFIED BALD AMERICAN REACH MALLARD GOLDENEYE MERGANSER DIVING DUCK EAGLE DIPPER TOTAL 1 1CE COVERED Total

4 Page 6 British Columbia Birds Volume 9,1999 seen frequently around barns and feed lots. They were missed during our surveys. He also indicated that Mallards frequently congregate in the same areas. This suggests that the four Mallards observed by us along the river are only a small proportion of the Mallards wintering in the area. Of the 268 Common Mergansers for which gender was recorded, 169 (63%) were male. Females are less conspicuous, and although we frequently circled larger flocks to confm numbers, we suspect that more females than males were missed. Thus, the 37% of total Common Mergansers estimated to be female is probably an underestimate. mergansers were observed on the shoreline or on the ice, they were immediately beside open water. The habitat association between Bald Eagles and open water could not be confirmed by the brief pass of a helicopter survey, but it is likely to be considerable. The Peace River is probably their main source of winter food, as suggested by the large concentration of eagles immediately below the W. A. C. Bennett Dam. Accidental passage through the dam by fish would leave many damaged or stunned and vulnerable to predators, such as mergansers and eagles. AUGUST 1999 SURVEY Behaviour and Habitat Use Birds observed were recorded as either swimming, flying, standing on shore or on the ice, or perching. By far the greatest proportion were swimming (Table 2), though the results vary from species to species. Most Common Mergansers (94%) and Common Goldeneyes (80%) were observed swimming. Few dove at our approach, and few flew. The behaviour that appears under represented, particularly with Common Mergansers, is the low number of those resting or standing on shore or at the ice edge. This is a species which is observed frequently roosting in small or large groups on rocks bordering rivers. It may be that heat loss associated with winter conditions is reduced by swimming, the water usually being warmer. Most Bald Eagles were flying, but a significant minority were perching on branches of large shoreline trees, or in the case of the flock downstream of the W. A. C. Bennett Dam standing near the mouth of a creek approximately 2 km. downstream of the dam. As indicated, virtually all birds except Bald Eagles were associated with open water habitat. Where, in a few cases, Abundance and Distribution In total 3482 birds were observed, of which 2094 (60%) were found between the Pine River and Cache Creek (Reaches 3 and 4), 27% of the linear study area. This coincides with major gull roosts and substantial numbers of Canada Geese and Mallards (Table 3). Though Reaches 3 and 4 contained the greatest numbers, significant numbers occurred throughout the 150 km. of the August 1999 study area. The concentration in Reaches 3 and 4 is based in part on flocks of gulls and waterfowl recorded both upstream and downstream of the Moberly River confluence. Within this area were two concentrations of gulls in excess of 300 individuals resting on gravel bars. The close proximity of Fort St. John with its garbage dump, sewage lagoons and other food sources could have influenced this distribution. Whereas anthropogenic factors influenced the late summer distribution of gulls, Canada Geese and Mallards, different patterns were exhibited by other species. Among species recorded along all reaches, Bald Eagles and Spotted Sandpipers (Actitis macularia) were unique in being relatively evenly distributed. The numbers of most other species were too low to draw any conclusions about distribution patterns. TABLE 2 BEHAVIOUR OF WATER-ASSOCIATED BIRDS OBSERVED DURING WINTER SURVEYS OF THE PEACE RIVER, 15 FEBRUARY 1996 STANDING ON ICE SPECIES SWIMMING FLYING OR SHORE PERCHING Mallard 0 4 Common Goldeneye 8 2 Common Merganser Unidentified diving duck 7 7 Bald Eagle 0 19 American Dipper 0 1

5 Volume 9,1999 British Columbia Birds Page 7 TABLE 3 BIRDS OBSERVED DURING AERIAL SURVEY OF THE PEACE RIVER DOWNSTREAM OF THE PEACE CANYON DAM AS FAR AS THE B.C./ALBERTA BORDER 20 AUGUST 1999 SPECIES RIVER REACH TOTAL Great Blue Heron Canada Goose swan sp. American Wigeon Mallard Northern Shoveler Northern Pintail Green-winged Teal Common Merganser duck species Bald Eagle Northern Goshawk Red-tailed Hawk American Kestrel falcon sp. Killdeer yellowlegs sp. Spotted Sandpiper sandpiper sp. Bonaparte's Gull gull sp. Belted Kingfisher Total Species Composition Of the total of 3482 birds observed, 2225 were waterfowl (63.9%), 946 gulls (27.2%), 276 shorebirds (7.9%) and 29 raptors (0.8%). Among the waterfowl, the most numerous were Canada Geese (905) and Mallards (885), which comprised 26% and 25.4% respectively of all the birds observed fiom the air (Table 3). The other waterfowl were primarily dabbling ducks: Green-winged Teal (Anus crecca) (240), American Wigeon (A. americana) (73), Northern Pintails (A. acuta) (47), Northern Shovelers (A. clypeata) (20) and unidentified swans (13). In addition to these observations, ground observations by Glenn Ryder in 1975 confmed Trumpeter Swan (Cygnus buccinator) in floodplain habitats, as well as Cinnamon Teal (Anas cyanoptera) and Gadwall (A. strepera) (Ryder 1975). The only diving ducks confmed fiom the air were Common Mergansers (40). The number observed is much fewer than the 166 recorded on comparable reaches in February Common Goldeneye was observed in back channel habitat during the associated ground surveys. Gulls, particularly in late summer, are difficult to distinguish to species and even more so during aerial surveys. From the air most gulls were classified as gull species. From a vessel we were able to confm a significant proportion of these as Ring-billed (Larus delawarensis) and Herring (L. argentatus) gulls. Bonaparte's Gulls (L. philadelphia) were also observed. Most (55%) of the shorebirds observed were identified as Spotted Sandpipers (1 52). Killdeer (Charadrius vociferus) was also confumed from the air. The 106 birds classified as sandpiper sp. probably comprised a significant proportion of Greater Yellowlegs (Tringa melanoleuca), Lesser Yellowlegs (T. flavipes) and Solitary Sandpipers (T. solitaria), species we confirmed during ground surveys. Raptor surveys were dominated by Bald Eagles. From the air we detected 26: ten adults, 16 irnrnatures, plus four nests. We also observed individual Red-tailed Hawk (Buteo jamaicemis), Northern Goshawk (Accipiter gentilis) and American Kestrel (Falco sparverius) fiom the air. On the ground, we recorded three Merlins (F. columbarius) and one Great Homed Owl (Bubo virginianus).

6 Paae 8 British Columbia Birds Volume Individual Great Blue Herons (Ardea herodias) were observed once fiom the air between the Pine and Moberly rivers, and once during ground surveys approximately 8 km. east of Taylor. Both were in backchannels on the north side of the river. As of 1990, there were very few records of this species fiom the Peace River (Campbell et al. 1990). Habitat Use Species specific differences in habitat occurrence may illuminate how species use the river a able 4). While most species used non-mainstem, or backchannel habitats, certain very numerous species were observed most fiequently on the mainstem. Species using non-mainstem habitats were primarily dabbling ducks and unidentified sandpipers. Although the majority of Canada Geese were found in or beside mainstem habitats, almost 400 were observed while in or beside back channels. The comparatively low energy, unscoured habitats of the back channels, blocked in some cases by beaver dams, provide a productive habitat for foraging by these species. DISCUSSION Both surveys described here provide brief snapshots of use by water-associated birds of the Peace River. The winter survey (February 1996) indicated a wintering avifauna of limited numbers composed primarily of two species: Common Merganser and Bald Eagle. In fact, our results showed both TABLE 4 HABITAT OCCURRENCE OF WATER-ASSOCIATED BIRDS RECORDED ON 20 AUGUST 1999 AERIAL SURVEY HABITAT OCCURRENCE SPECIES MAINSTEM NON-MAINSTEM Canada Goose swan sp American Wigeon 5 68 Mallard Northern Shoveler 0 20 Northern Pintail 3 44 Green-winged Teal Common Merganser Killdeer 3 11 Spotted Sandpiper sandpiper sp Bonaparte's Gull 79 3 gull sp Four species or species groups were observed primarily on or beside the mainstem: Canada Geese, Common Mergansers, Spotted Sandpipers and gulls (Table 4). The gulls and geese were observed in large concentrations resting or loafing on gravel bars. Most mergansers (70%) were observed swimming in the mainstem or resting on large cobbles immediately adjacent to the mainstem. The Spotted Sandpipers were usually observed flying in response to our survey helicopter; therefore, their behaviour (e.g., foraging, resting) was interrupted by the survey. From our observations during ground or boat surveys, Spotted Sandpipers were foraging individually, or rarely in small flocks (< five) along or close to the water's edge. species to be more numerous in winter than in summer. This applies particularly in the case of Common Merganser in which numbers were more than seven times greater. The Peace River now appears to attract wintering Common Mergansers. Bald Eagle numbers were sufficiently similar between winter and summer results to discourage generalizations, except that winter conditions particularly below the W. A. C. Bennett Dam are favourable for both species. Common Goldeneyes were the third species in abundance, and their recorded numbers might have been greater than indicated if many of the unidentified diving ducks were confirmed as this species, as they likely were.

7 Volume British Columbia Birds Page 9 While the temperature of water discharged from the dams may explain the new phenomenon of open water, it is only part of the imperfectly understood story. The W. A. C. Bennett Dam entrains a significant number of fish, primarily whitefish (Coregonidae), but also significant numbers of kokanee salmon (Oncorhynchus nerka) (Robert Westcott personal communication). This turbulent experience kills, injures, or at least stuns many of the fish processed in this way, leaving them vulnerable to predation by birds and larger fish. This explains much of the concentration of Common Mergansers and Bald Eagles immediately below the W. A: C. Bennett Dam. Concentrations of Common Mergansers below the Peace Canyon Dam were much fewer: 45 compared to 140, reflecting perhaps the less injurious effects of entrainment through the downstream dam. Though there is limited winter survey information on bird use of northern rivers, the pattern described here for the Peace River has been observed elsewhere. Near Montreal, Quebec, Reed and Bourget (1977) conducted counts which enumerated 8787 waterfowl, of which approximately 60% were Common Mergansers and 33% Common Goldeneyes. They pointed out that nearby dams on the St. Lawrence River appeared to attract Common Mergansers; the distribution of Common Goldeneyes indicated that they were not influenced by dams. These generalizations may apply here. The summer avifauna bore little similarity to that of winter, and at least some of this was a reflection on the expanded habitats available. The summer avifauna was far more numerous (3482 birds versus 366), had a richer species composition (17+ species versus five), and was distributed more evenly along the length and breadth of aquatic habitats on the river. In the absence of a partially frozen river cross-section, habitat use in summer extended to all habitats available. The high abundance was based primarily on the occurrence in large numbers of three species or species groups: Canada Goose, Mallard and gull species, primarily Ring-billed and Herring gulls. These amounted to 76% of all birds recorded during aerial surveys. By 20 August most breeding activities of aquatic birds have long been completed and populations observed result from post-breeding dispersal, moulting distribution and "fall" migration added to resident populations. No significant gull colonies have been documented in the study area (Campbell et al. 1990), and though sub-adults probably occur during the breeding season, the numbers observed probably represent a concentration of adult and young gulls dispersed from breeding colonies elsewhere in western Canada. Canada Geese breed in the Peace River floodplain. Donald Blood (1978) recorded 51 breeding pairs in Peace River floodplain habitats between the mouth of the Moberly River and the town of Hudson's Hope. He also confirmed a small number of broods (" 12 or 13"). and ascribed the numerical discrepancy to pairs enumerated on the Peace River breeding in adjacent uplands. Based on these numbers, generated from only part of our study area (Reaches 4-7), 1 hypothesize that the Canada Geese recorded in our study are largely local, representing adults and fledged young from both Peace River floodplain and surrounding floodplain and upland habitats. Blood (1978) found 92 pairs of Mallards in the same reaches, plus significant numbers of Northern Pintails (52), American Wigeon (50) and Green-winged Teal (28). This confums that the backchannel habitats along the Peace River are at least moderately productive for waterfowl, and that the numbers of Mallards and other dabbling ducks recorded during our surveys can be attributed to a largely local population. Species observed during this study were recorded mostly from the air, and given the non-breeding plumages of late August plus observer error, many species recorded by others in late summer were missed. Additional species observed by Glenn Ryder during August 1975 were Canvasback (Aythya valisineria), Redhead (A. americana), Ring-necked Duck (A. collaris), Lesser Scaup (A. afinis), Harlequin Duck (Histrionicus histrionicus), Surf Scoter (Melanitla perspicillata), White-winged Scoter (M fusca), Bufflehead (Bucephala albeola), Hooded Merganser (Lophodytes cucullatus) and Ruddy Duck (Oxyura jamaicensis) (Ryder 1975). The only diving ducks confmed from the air during our August surveys were Common Mergansers (40). In his study area (Reaches 4-7), Blood (1978) recorded 38 Common Merganser breeding pairs and confmed two broods as part of incidental observations. The most common diving duck during the breeding season was Common Goldeneye -56 pairs (Blood 1978). In total, 12 Common Goldeneye broods were found by Blood. Shorebirds constituted a focal species group during the August 1999 surveys, and the timing of surveys was influenced partly by trying to coincide with southward migrating shorebirds. We confirmed Killdeer and Spotted Sandpiper from the air and added Greater and Lesser yellowlegs and Solitary Sandpiper from ground surveys. During ground surveys, Blood (1978) estimated that in suitable habitat in excess of two nesting pairs of Spotted Sandpipers occurred per kilometre of shoreline, and about one-tenth of that for Killdeer; this amounted to an estimated 400 or more nests of Spotted Sandpiper between the Moberly River confluence and Hudson's Hope and 40 nests of Killdeer. Beyond that, Blood (1978) concluded that while thousands of shorebirds pass through on migration, most do not use the floodplain habitat. The results described here are consistent with that conclusion. Habitat use was examined only roughly during this study, limiting the confidence of our inferences. Species occurring in the mainstem were observed swimming (a small minority) or roosting in large assemblages on exposed gravel and cobble bars.

8 Page 10 British Columbia Birds Volume Many of these were situated at the downstream end of midchannel islands, where the flow of back channels meets that of the mainstem. This alone provided a challenge in recording habitat occurrence. Campbell, R. W., N. K. Dawe, I. McTaggart-Cowan, J. M. Cooper, G. W. Kaiser and M. C. E. McNall The birds of British Columbia. Volume 2. Royal British Columbia Museum, Victoria. The back channels were varied in several ways. Small differences in their elevation determine the frequency with which they are exposed to the cooling waters of the river with their potential to scour and thus alter substrates. Hawkes and Fraker (2000) commented on how the elevational variation in Peace River back channels affects water temperature, velocity, substrate and reproductive success in amphibians. Physical variables, such as these are likely to influence use by waterfowl for breeding, foraging and related uses. The population of American Beaver (Castor canademis) is considerable -estimated at 59 colonies and 336 beavers in August 1999 (Fraker and Hawkes 2000). Many back channels were dammed by beaver, creating local water level stability beyond that now occurring in the system, and possibly increasing their use by waterfowl. Use of rivers by waterfowl has attracted much attention only recently. When the Canada Land Inventory (1972) mapped wetlands for their capability to produce waterfowl, the Peace River floodplain and other riverine habitats were classified along with the surrounding uplands as having severe limitations to waterfowl production. No distinction was made for the wetlands of the floodplain. With a broadened faunistic interest extended to include species at risk, such as Harlequin Ducks, the B. C. Resources Inventory Committee now has standards for inventories of riverine birds (Resources lnventory Committee 1997). ACKNOWLEDGEMENTS Additional personnel involved in aerial and ground surveys were Glenn Ryder and Kenneth Summers in February 1996 and Mark Fraker and Virgil Hawkes in August Robert Wescott, biologist, B.C. Hydro, described the process of fish entrainment in dams, and the main species entrained in this manner at the W. A. C. Bennett Dam. Ed Hill, B.C. Hydro biologist, supervised the two studies from which observations are summarized in this paper. Ken Morgan and Gary Davidson contributed usehl comments on an earlier draft of the manuscript. LITERATURE CITED Beasley, B. A Preliminary inventory manual for waterfowl and allied species in British Columbia. Draft report to Resources Inventory Committee, Ministry of Environment, Lands and Parks, Victoria. Canada Land Inventory Land capability for wildlife - waterfowl; map sheet 94A, Ottawa. Fraker, M. A. and V. C. Hawkes Aquatic mammals and incidental observations. Chapter 4 in M. A. Fraker and V. C. Hawkes (Editors). Peace River wildlife surveys: TerraMar Environmental Research Ltd. report to B.C. Hydro, Burnaby. Hawkes, V. C. and M. A. Fraker Amphibians and reptiles. Chapter 3 in M. A. Fraker and V. C. Hawkes (Editors). Peace River wildlife surveys: TerraMar Environmental Research Ltd. report to B.C. Hydro, Burnaby. Reed, A. and A. Bourget Distribution and abundance of waterfowl wintering in southem Quebec. Canadian Field- Naturalist 9 1 : 1-7. Resources Inventory Committee Measuring components of British Columbia's biodiversity: riverine bird inventory manual. B. C. Ministry of Environment, Lands, and Parks, Victoria. Resources Inventory Committee lnventory methods for waterfowl and allied species: loons, grebes, swans, geese, ducks, American Coot, and Sandhill Crane. Standards for components of British Columbia's biodiversity No. 18. B. C. Ministry of Environment, Lands, and Parks, Victoria. Robertson, I. and V. C. Hawkes Water-associated birds. Chapter 2 in M. A. Fraker and V. C. Hawkes (Editors). Peace River wildlife surveys: TerraMar Environmental Research Ltd. report to B. C. Hydro, Bumaby. Robertson, I., K. Summers and G. R. Ryder Peace River waterfowl survey, winter Robertson Environmental Services report to B. C. Hydro, Burnaby, B.C. UNPUBLISHED DOCUMENT CITED Ryder, G Field notes. Survey of birds in Peace River floodplain habitats. Prepared for birds of British Columbia project. Blood, D. A Wildlife sub-report, Peace River Site C hydroelectric development, environmental and socioeconomic assessment. Donald A. Blood & Associates report to B. C. Hydro, [Vancouver].