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Boundary Bay - Roberts Bank - Sturgeon Bank (Fraser River Estuary) (BC017)

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Boundary Bay - Roberts Bank - Sturgeon Bank (Fraser River Estuary) (BC017)

Delta, Richmond, Surrey, White Rock, British Columbia

Latitude 49.100°N
Longitude 122.968°W
Altitude 0 - 5m
Area 753.96km²

Site Description

The Boundary Bay - Roberts Bank - Sturgeon Bank site (Fraser River Estuary) is a large complex of interconnected marine, estuarine, freshwater and agricultural habitats in southwestern British Columbia near the city of Vancouver. It includes Boundary Bay, a predominantly marine ecosystem, the estuarine waters of Sturgeon Bank, between the north and south arms of the Fraser River, and Roberts Bank, south of the south arm of the Fraser River. Maritime habitats in the IBA include sand and mud flats, eelgrass, salt marshes, estuarine marshes with sedge, cattails and bulrush and deeper tidal waters. Agricultural habitats within the IBA include the fertile, deltaic farmlands of Richmond, Delta, and south Surrey, which provide important habitat for waterfowl, shorebirds and birds of prey. Patches of forest, including mature coastal Douglas-fir, provide important nesting and roosting habitat for Great Blue Herons and raptors, including Bald Eagles. The network of rivers (Fraser, Serpentine, Nicomekl and Little Campbell) and associated wetlands within the site provided historical as well as current and potential future habitat for waterbirds. Burns Bog, lying in the heart of the delta, is a sphagnum moss wetland surrounded by shore pine and alder forest.

Birds

Boundary Bay, Roberts Bank and Sturgeon Bank form one of the richest and most important ecosystems for migrant and wintering waterbirds in Canada. This IBA supports globally or continentally significant populations of fifteen species, including American Wigeon, Northern Pintail, Mallard, Brant, Snow Goose, Trumpeter Swan, Western Sandpiper, Black-bellied Plover, Dunlin, Great Blue Heron, Western Grebe, Red-necked Grebe, Glaucous-winged Gull, Thayer's Gull, and Mew Gull. In addition, the IBA supports nationally significant numbers of Barn Owl and Peregrine Falcon.

In total, fifty species of shorebirds have been recorded in the area. The most numerous species found here is the Western Sandpiper - one-day, peak count estimates of at least 500,000 have historically (pre-2001) occurred during spring migration, though more recent estimates range from 120,000-180,000, which is a substantial proportion of the global Western Sandpiper population. Western Sandpiper also pass through on fall migration. Dunlin also occur in large numbers - one-day, peak counts in the spring exceeded 100,000 in 2004 and typically range from 26,000-85,000 birds. Large numbers of Dunlin can occur during fall migration and also overwinter in the delta. Black-bellied Plovers occur during winter and on migration, with one day counts of up to 6,000 birds. Dunlin and Black-bellied Plovers use both agricultural and estuarine habitats.

A significant proportion of the Wrangel Island Snow Goose population uses the banks; up to 38,400 regularly winter here; high numbers also occur on passage in fall and spring. The numbers of Snow Geese using the banks change significantly even within one winter because the birds move back and forth to the nearby Skagit River Delta in Washington State. Counts of 60,000 for the entire Fraser-Skagit Delta population are not uncommon between late October and March; about 100,000 birds were counted in 2007. During the fall and early winter, one-day counts of greater than 100,000 dabbling and diving ducks are made regularly in the IBA for species such as American Wigeon (up to 51,000), Northern Pintail (up to 44,000), Mallard (up to 27,000) and Green-winged Teal. Surf Scoters occur in large numbers in marine waters during the winter and in spring (typically 1,000-8,000 individuals); with populations exceeding global IBA thresholds twice since 2001. Many dabbling ducks use the agricultural lands and estuarine habitats.

Significant numbers of Trumpeter Swans winter in the IBA (up to 1,455 in 2010). Brant winter in marine waters of the IBA (4,080 in 2010) and pass through on spring migration. Most are Black Brant (Branta bernicla nigricans). In recent years, about 200 Western High Arctic, or Grey-bellied Geese have been present in winter. During the late summer and early fall, the area is also very important for moulting grebes. Historically, between 2,000 and 3,000 Western Grebes were regularly present in Boundary Bay, and a separate study reported over 2,000 on the estuarine banks (Stout and Cooke 2003, Butler and Cannings 1989). In recent years, Western Grebes have declined steeply; counts since 2003 have ranged from 200-1000 individuals and no longer exceed IBA thresholds. This significant decline has been noted throughout the Salish Sea (in British Columbia and Washington); the reasons for the decline are not clear and are under investigation (Wilson et al. 2013). Red-necked Grebes are also present in the IBA during spring and fall migration and winter; counts have exceeded IBA thresholds in four years since 2001, with a peak count of 2,716 in 2002.

Glaucous-winged Gulls are present year-round and occur in significant numbers during the winter, with a peak count exceeding 55,000 in 2006. Large numbers feed at the Vancouver Landfill in Burns Bog and roost on surrounding fields and on marine waters of Boundary Bay, Roberts and Sturgeon Banks. Significant numbers of Mew Gulls are also present in the fall (counts up to 1,217 in 2007) and winter (up to 3,770 in 2005). Thayer's Gull occurs in significant numbers in the winter as well, with up to 623 counted in 2001.

The IBA supports important numbers of three species determined to be Threatened or Special Concern by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC; wildlife species that have been assessed as at risk by COSEWIC may qualify for legal protection and recovery under Canada's Species at Risk Act). Great Blue Heron (A.h. fannini subspecies) (Special Concern, COSEWIC) has several colonies in the IBA, including a very large one on a forested bluff adjacent to Roberts Bank and the Tsawwassen ferry jetty, with about 250-450 nests (Welstead, pers comm.). These herons are resident, and feed in intertidal areas during the breeding season, as well as on farmland, especially in winter. Barn Owl (Threatened, COSEWIC) nest in and around farmlands within the IBA; up to 106 nest sites were active over six years from 2006-2012 (Hindmarch, pers comm.). Peregrine Falcon (Special Concern, COSEWIC) regularly occurs during the winter. The number of Bald Eagles using the IBA in the winter has also increased in recent years and may exceed IBA thresholds in the future.

Conservation Issues

The major, immediate threat to the ecological integrity of this IBA is permanent loss, degradation (loss in quality) and fragmentation of habitats. The IBA overlaps Canada's third largest urban centre, Metro Vancouver, supporting a population projected to grow by 1.4 million by 2040, and the largest port on North America's west coast, Port Metro Vancouver, on which the region's economy is founded. Agricultural, estuarine and marine habitats have been, and continue to be lost and fragmented by current and proposed urban developments (e.g. the Southlands adjacent to Boundary Bay and Tsawwassen First Nation lands adjacent to Roberts Bank), industrial developments (e.g. major expansion of Port Metro Vancouver on Roberts Bank and adjacent upland), and related transportation and infrastructure developments (e.g. jetties, causeways, highways, bridges, rail yards, airports). Conversion of open agricultural fields to berry crops, greenhouses and other intensive uses has reduced farmland habitat available to waterfowl, shorebirds and owls (e.g. Barn Owl).

Terrestrial and aquatic habitat quality is reduced by runoff from urban, industrial and agricultural activities (Swains and Holms 1988) and dumping of contaminated water, although long-term and cumulative effects are poorly understood. Concerns about contamination from ballast water are lessened as long as de-ballasting takes place mid ocean as required. The risk of marine spills, including oil, will increase with proposed increases in shipping traffic to meet trade demands.

Changes in the marine food chain appear to be impacting some bird species. Forage fish, such as herring and sand lance, have declined in the Salish Sea in recent years, and a corresponding decrease in diving birds that predate on forage fish has been observed (Crewe et al. 2012, Anderson et al. 2009, Therriault et al. 2009).

A variety of introduced species present potential local and ecosystem level concerns. Exotic mollusks are common in intertidal areas, including Batillaria snail, Venerupis philippinarum (manila clam), and Nuttalia obscurata (purple varnish clam). Zostera japonica (exotic eelgrass) is present on Roberts Bank and in Boundary Bay. Spartina anglica (exotic cordgrass) is proving extremely difficult to control and has the potential to change intertidal mudflat to unproductive grassland (Knight 2012).

Direct mortality through fisheries by-catch (Hamel et al. 2009, BC Coast BirdWatch 2011), collisions or overhead transmission wires (Burger and Cassidy 1995), and illegal hunting (Environment Canada 2011) may have cumulative impacts on trigger species populations. Mitigation measures implemented on transmission wires have had some success, but have not eliminated collisions entirely (Cassidy et al 1998).

Widespread recreational disturbance, including hunting, dogs off leash, kite-boarding in shallow intertidal waters, and power boating in sensitive marine near shore habitats, causes migratory birds to re-distribute. The long term impacts of these disturbances are not known and need to be quantified.

Potential impacts of cumulative air and light pollution have not been studied.

Conservation management areas provide a degree of protection across approximately 45% of the IBA, mostly in the inter- and sub-tidal habitats. Alaksen National Wildlife Area (including Reifel Migratory Bird Sanctuary) and provincial Wildlife Management Areas (WMAs), including South Arm Marshes, Boundary Bay, Sturgeon Bank, Serpentine, and Roberts Bank WMAs, cover almost 40% of the IBA. The management plans for all WMAs except the Serpentine WMA need to be updated. Several regional and local parks include important mudflats and marsh habitats along the shore (e.g. Boundary Bay Regional Park and dyke trail, Mud Bay Park, Blackie Spit). Ducks Unlimited and The Nature Trust of BC own and manage important agricultural and intertidal land parcels, and 2,400 ha of Burns Bog have been designated as an Ecological Conservancy Area.

Much of the farmland within the IBA falls within the BC Agricultural Land Reserve, established to preserve agricultural land and encourage the establishment and maintenance of farms as a secure source of food. The Delta Farmland and Wildlife Trust coordinates stewardship programs that benefit farming and wildlife on over 1,400 ha of active farmland within the IBA.

The importance of the Fraser River Estuary is recognized through several other international designations. The Fraser River Estuary IBA was designated a Hemispheric Site under the Western Hemisphere Shorebird Reserve Network (WHSRN) in 2004. The Alaksen National Wildlife Area was originally designated as a Ramsar Wetland of International Significance in 1982. In 2012, this site was expanded from 586 to 20,682 ha, capturing Burns Bog, Sturgeon Bank, South Arm Marshes, Boundary Bay, and the Serpentine, and renamed the Fraser River Delta Ramsar Site. Roberts Bank Wildlife Management Area remains to be included in this Ramsar designation.

More than 25 non-government organizations, municipal, provincial and federal government agencies, academic institutions and private environmental consulting companies are actively working to research, monitor, build awareness, and improve habitat for birds and other wildlife within the IBA, including the Boundary Bay Conservation Committee, the Friends of Semiahmoo Bay Society, the A Rocha Field Centre, Burns Bog Conservation Society, Delta Naturalists' Society, White Rock and Surrey Naturalists, Nature Vancouver, Langley Field Naturalists, Surrey Environmental Partners Society, WildResearch, Bird Studies Canada, BC Nature, Pacific Wildlife Foundation, Little Campbell Watershed Society, TerraNova Birders, the Ladner and Tsawwassen Rotary Club, the Centre for Wildlife Ecology at Simon Fraser University, and Environment Canada, to name a few. From 1985 -2013, the now defunct Fraser River Estuary Management Program provided a framework for environmental coordination in conjunction with ongoing economic development, but effective ecosystem-scale conservation planning and management has always been, and continues to be, challenged by the large number of local, provincial and federal authorities with jurisdiction over different parts of the IBA.

IBA Criteria Habitats Land Uses Potential or Ongoing Threats Conservation Status
Red-throated Loon
Number Year Season
3492012Winter
405 - 4872001Spring
7,0002000Spring
Iceland Gull (Thayer's)
Number Year Season
110 - 3002017Winter
1502016Winter
6002015Winter
205 - 5002014Winter
1712013Winter
2452013Spring
200 - 2882012Winter
1612011Winter
312011Fall
500 - 1,0442010Winter
1872009Spring
187 - 2002009Winter
200 - 4172008Winter
320 - 4172007Winter
80 - 2562006Winter
100 - 2052005Winter
167 - 2052004Winter
155 - 1672003Winter
45 - 1552002Winter
1262001Spring
243 - 6232001Winter
100 - 2842000Winter
912000Fall
115 - 8511997Winter
1151997Spring
5001996Winter
139 - 1,5131995Winter
5121994Winter
3321993Winter
183 - 6941991Winter
96 - 7281990Winter
Western Sandpiper
Number Year Season
30,0002015Spring
30,000 - 64,6002014Spring
28,0002013Spring
30,000 - 50,0002012Spring
20,000 - 175,9802010Spring
50,000 - 120,0002009Spring
139,8402008Spring
171,0002007Spring
166,6052006Spring
106,6402005Spring
77,7702004Spring
110,9362003Spring
100,3032001Spring
174,0002000Spring
20,0001995Spring
500,0001992Spring
45,3001990Fall
55,8181988Summer
13,6581978Summer
180,044?Other
Surf Scoter
Number Year Season
1,6002011Winter
8002010Winter
1,1412009Spring
10,0002009Winter
1,0002008Spring
1,5002007Spring
6,0002006Winter
6,0002005Spring
6,0002005Winter
8,0002004Fall
9362003Winter
3,0002002Spring
6,000 - 28,2002001Spring
6,4002001Winter
10,000 - 90,0122000Spring
10,4002000Winter
18,0001998Spring
8,0001997Spring
Glaucous-winged Gull
Number Year Season
5,000 - 6,0002017Winter
4,500 - 7,0002016Winter
4,800 - 6,5002016Fall
5,0002015Winter
7,0002015Fall
17,0392014Winter
37,0792013Winter
38,5372012Winter
4,000 - 40,5632011Winter
6,742 - 46,4242010Winter
40,594 - 47,9292009Winter
47,9292009Spring
30,0492008Winter
6,000 - 53,3802007Winter
6,000 - 55,8032006Winter
6,934 - 55,8032005Winter
4,126 - 6,9342004Winter
47,7282003Winter
28,472 - 47,7282002Winter
28,472 - 32,1882001Winter
5,0002001Fall
8,366 - 32,1882000Winter
5,0001998Winter
7,5211997Winter
19,000 - 20,5311995Winter
4,724 - 42,0001994Winter
20,6071993Winter
5,000 - 10,8001992Winter
9,000 - 22,0361991Winter
25,3891990Winter
44,8321980Winter
Dunlin
Number Year Season
17,000 - 30,0002016Fall
11,800 - 30,0002016Spring
13,293 - 41,0002016Winter
15,000 - 40,0002015Fall
13,050 - 40,0002015Spring
35,000 - 50,0002015Winter
15,000 - 30,0002014Winter
12,000 - 20,0002014Fall
15,0002014Spring
20,000 - 50,0002013Winter
15,000 - 28,0002013Spring
18,000 - 48,2132012Winter
20,0002012Fall
15,000 - 50,0002012Spring
12,354 - 50,5562011Winter
17,000 - 40,0002011Fall
12,060 - 70,0002011Spring
14,500 - 55,4972010Winter
15,0002010Fall
20,000 - 50,5732010Spring
15,000 - 42,4132009Winter
30,0002009Fall
42,413 - 50,6542009Spring
12,000 - 65,0002008Winter
12,600 - 85,0502008Spring
15,000 - 56,5442007Winter
40,0002007Fall
23,000 - 78,9602007Spring
20,312 - 41,3792006Winter
105,0002006Fall
46,3782006Spring
25,508 - 65,8612005Winter
50,7212005Spring
65,861 - 79,5072004Winter
105,6002004Spring
79,507 - 84,7732003Winter
61,3342003Spring
15,000 - 84,7732002Winter
12,000 - 20,0002002Fall
16,000 - 60,4932001Winter
15,000 - 26,8112001Spring
12,500 - 60,4932000Winter
17,000 - 60,0002000Fall
15,000 - 26,0002000Spring
30,0001999Fall
12,485 - 16,3721998Winter
16,930 - 35,1201997Winter
16,9301997Spring
18,0001996Spring
50,0001996Winter
28,953 - 29,0001995Winter
20,0001995Spring
13,570 - 16,9001994Winter
33,1681993Winter
49,7131992Winter
25,0001992Fall
17,381 - 61,1061991Winter
20,0051990Winter
92,8051989Winter
53,0171988Winter
76,398 - 97,4811988Fall
126,2851988Spring
60,0001978Winter
50,0001976Fall
36,464?Other
Western Grebe
Number Year Season
1,0002014Spring
1,0002011Spring
2002010Winter
3532009Fall
4702008Spring
2102007Spring
2602006Fall
6502005Winter
9002004Winter
2,0932003Fall
1,400 - 3,2002003Winter
2,4262002Spring
1,3002001Spring
1,5002001Winter
1,4332000Fall
942 - 7,2732000Spring
2,1612000Winter
1,0001999Winter
1,000 - 3,0001998Fall
5,0001996Winter
1,4951991Winter
1,052 - 2,1091988Fall
1,0681988Spring
Red-necked Grebe
Number Year Season
5802015Fall
6362014Fall
4192013Fall
3922012Fall
922011Fall
1752010Fall
790 - 7912009Fall
3622008Fall
2272007Fall
1512006Fall
912005Fall
2422004Winter
4852003Winter
462 - 8102002Fall
2,7162002Spring
7102001Fall
780 - 1,0002000Fall
7031999Winter
603 - 7001999Fall
2,5761998Fall
5001997Fall
Trumpeter Swan
Number Year Season
3772017Winter
3102016Winter
440 - 5002015Winter
300 - 8122014Winter
2752013Spring
500 - 6502013Winter
1,4182012Winter
2942012Fall
375 - 9032011Winter
3302011Fall
287 - 1,8672010Winter
400 - 4382010Fall
300 - 1,4552009Winter
4302009Spring
2842008Fall
432 - 7232008Winter
357 - 9262007Winter
343 - 5002007Spring
260 - 9262006Winter
692 - 9332005Winter
260 - 9332004Winter
300 - 8532003Winter
260 - 8532002Winter
810 - 8342001Winter
8102000Winter
3001999Winter
270 - 5731998Winter
551 - 8601997Winter
5511997Spring
4001996Winter
311 - 6451995Winter
3751995Fall
425 - 7761994Winter
300 - 7001992Winter
3251991Winter
4311990Winter
Black-bellied Plover
Number Year Season
2,500 - 2,8502017Fall
3,3602016Spring
2,0002015Fall
1,7202015Spring
2,1002015Winter
3,1602014Winter
2,000 - 2,5002014Fall
2,000 - 2,5002013Fall
1,700 - 2,5002012Fall
1,792 - 2,1342011Winter
2,000 - 5,0002011Fall
1,600 - 3,0402010Fall
3,0402010Summer
1,8082009Winter
1,600 - 2,0002009Fall
2,5002008Fall
2,1042008Spring
1,7052008Winter
1,948 - 3,7282007Winter
3,0002007Fall
3,7282006Winter
2,8002006Fall
1,613 - 6,8552005Winter
2,1152005Spring
6,028 - 6,8552004Winter
5,7502004Fall
1,950 - 6,0282003Winter
1,9502002Winter
2,0002002Fall
1,2422001Winter
2,000 - 2,5002000Fall
8,0002000Spring
3,0001994Fall
2,0611992Winter
1,6001990Winter
4,2861988Fall
4,5471988Spring
Red-breasted Merganser
Number Year Season
5,0002001Spring
2,1202001Winter
6,7002000Spring
American Wigeon
Number Year Season
20,0002015Winter
20,0002015Fall
19,5862014Winter
30,480 - 51,3142013Winter
17,7992012Winter
11,450 - 58,8602011Winter
25,054 - 38,8172010Winter
15,659 - 22,0002010Fall
14,284 - 25,0542009Winter
28,0002008Fall
37,4382008Winter
19,700 - 37,4382007Winter
21,650 - 37,0002007Fall
15,122 - 48,2032006Winter
22,000 - 35,5002006Fall
20,143 - 48,2032005Winter
20,143 - 47,2522004Winter
43,0002004Fall
23,886 - 47,2522003Winter
35,418 - 39,2352002Winter
35,418 - 50,8712001Winter
50,8712000Winter
25,0002000Fall
22,5711998Winter
27,3001997Winter
30,170 - 30,5001995Winter
25,8531994Winter
53,1791993Winter
28,9891992Winter
57,9011991Winter
29,2741988Winter
34,144 - 50,6101988Fall
42,7261982Winter
Northern Pintail
Number Year Season
30,0002016Fall
20,000 - 25,0002015Fall
23,8112013Winter
25,0002012Fall
21,4962011Winter
14,4152011Fall
11,232 - 38,6852010Winter
18,000 - 33,0002010Fall
12,9592009Winter
17,9312008Winter
15,500 - 27,9192007Winter
27,9192006Winter
19,5002006Fall
11,4432005Winter
17,000 - 36,5002004Fall
43,8302004Winter
25,730 - 43,8302003Winter
17,098 - 25,7302002Winter
31,4132001Winter
31,4132000Winter
31,600 - 37,0002000Fall
23,092 - 24,9401995Winter
39,1851994Winter
23,0531993Winter
26,0701992Winter
55,0701991Winter
29,1721988Winter
22,412 - 30,3991988Fall
10,1861988Spring
48,9811982Winter
Northwestern Crow
Number Year Season
11,000 - 13,2322012Winter
29,1182011Winter
12,3292010Winter
Long-billed Dowitcher
Number Year Season
1,500 - 2,6002010Fall
Bonaparte's Gull
Number Year Season
4,0002013Spring
White-winged Scoter
Number Year Season
12,1112001Spring
6,300 - 10,0102000Spring
Mew Gull
Number Year Season
6772009Fall
1,6632008Winter
1,2172007Fall
1,4592006Winter
3,7702005Winter
1,748 - 3,7702004Winter
6292003Fall
8982002Winter
4,5322001Spring
3,6262001Winter
5,9102000Spring
Greater Scaup
Number Year Season
5,1032007Winter
6,9002000Spring
6,1661993Winter
6,000 - 8,1651991Winter
Brant
Number Year Season
3,0002017Spring
4,5002016Spring
4,8002014Winter
2,8392013Winter
4,3702013Spring
3,5002012Spring
1,0512012Winter
1,4762011Winter
1,3782011Fall
4,0802010Fall
3,1002010Spring
2,8782006Winter
2,4282000Spring
27 - 4,7511999Spring
2001999Winter
4,7631998Spring
Green-winged Teal
Number Year Season
23,4721991Winter
Sanderling
Number Year Season
2,500 - 3,0002011Spring
Great Blue Heron
Number Year Season
45 - 802017Fall
200 - 4402017Summer
70 - 3402017Spring
47 - 622017Winter
42 - 1532016Winter
39 - 2002016Fall
68 - 4002016Summer
250 - 3322016Spring
40 - 1802015Fall
100 - 3002015Summer
35 - 1702015Spring
111 - 1752015Winter
35 - 3172014Winter
35 - 602014Fall
132 - 3752014Summer
40 - 2662014Spring
38 - 1842013Winter
36 - 1052013Fall
40 - 1902013Summer
51 - 2682013Spring
85 - 2452012Winter
50 - 622012Fall
60 - 4002012Summer
35 - 1572012Spring
125 - 2122011Winter
50 - 812011Fall
53 - 2232011Summer
44 - 2782011Spring
35 - 2582010Winter
40 - 702010Fall
35 - 372010Summer
38 - 1502010Spring
158 - 2582009Winter
41 - 1002009Fall
34 - 1252009Summer
50 - 1582009Spring
35 - 732008Fall
50 - 1682008Summer
45 - 2022008Spring
2022008Winter
115 - 2792007Winter
34 - 752007Fall
34 - 832007Summer
402007Spring
123 - 2792006Winter
40 - 902006Fall
802006Summer
622006Spring
50 - 2932005Winter
43 - 1682005Fall
752005Summer
2622004Winter
34 - 962004Fall
4522004Summer
36 - 702004Spring
114 - 2542003Winter
372003Fall
64 - 1452003Summer
35 - 2972002Winter
50 - 1972002Fall
912002Summer
162 - 2972001Winter
35 - 722001Fall
80 - 1102001Summer
41 - 752001Spring
109 - 2692000Winter
35 - 862000Fall
34 - 1202000Summer
36 - 572000Spring
121 - 1501999Winter
50 - 1941999Fall
36 - 4001999Summer
94 - 1711998Winter
341998Fall
1201998Summer
451998Spring
35 - 961997Fall
35 - 1391997Spring
74 - 1391997Winter
6921997Summer
1001996Winter
50 - 771996Fall
84 - 2061995Winter
50 - 591995Fall
51 - 1,0001995Summer
881995Spring
128 - 1551994Winter
401994Fall
4091994Summer
46 - 2001994Spring
82 - 2001993Winter
50 - 1501993Fall
1501993Spring
36 - 2181992Winter
36 - 601992Fall
501992Spring
140 - 2151991Winter
471991Spring
2221990Winter
2511981Winter
Barn Owl
Number Year Season
72016Winter
7 - 122014Winter
72013Winter
9 - 202012Winter
982012Summer
72011Winter
622011Summer
10 - 172010Winter
822010Summer
11 - 172009Winter
112009Spring
802008Summer
92008Winter
9 - 142007Winter
602007Summer
11 - 142006Winter
132005Winter
62004Winter
142003Winter
14 - 152002Winter
13 - 152001Winter
11 - 172000Winter
12 - 141999Winter
8 - 111998Winter
8 - 121997Winter
81996Spring
15 - 191995Winter
13 - 151994Winter
15 - 241993Winter
151992Winter
12 - 211991Winter
141990Winter
Peregrine Falcon
Number Year Season
2 - 52017Fall
22017Summer
22017Spring
22017Winter
2 - 92016Winter
2 - 32016Fall
22016Summer
22016Spring
22015Winter
2 - 52015Fall
32015Summer
2 - 42015Spring
2 - 282014Winter
3 - 52014Fall
22014Summer
2 - 42014Spring
2 - 132013Winter
2 - 62013Fall
22013Spring
2 - 152012Winter
2 - 42012Fall
2 - 32012Spring
2 - 242011Winter
2 - 52011Fall
2 - 32011Spring
2 - 182010Winter
2 - 42010Fall
2 - 52010Spring
2 - 292009Winter
22009Fall
2 - 172009Spring
2 - 42008Winter
2 - 42008Fall
2 - 32008Spring
2 - 132007Winter
22007Fall
2 - 212006Winter
22006Fall
22006Spring
2 - 212005Winter
2 - 172005Fall
2 - 162004Winter
22004Fall
22004Spring
2 - 222003Winter
2 - 32003Fall
2 - 212002Winter
2 - 32002Fall
2 - 152001Winter
2 - 32001Fall
22001Summer
22001Spring
2 - 182000Winter
22000Fall
22000Spring
3 - 61999Winter
2 - 31999Fall
4 - 61998Winter
2 - 31998Fall
2 - 51997Winter
2 - 31997Fall
51997Spring
31996Winter
21996Fall
2 - 71995Winter
21995Fall
5 - 101994Winter
21994Fall
2 - 71993Winter
2 - 31993Fall
81992Winter
3 - 81991Winter
51990Winter
Western Screech-Owl
Number Year Season
12006Winter
12000Winter
11999Winter
11998Winter
11997Winter
11995Winter
11994Winter
11993Winter
21991Winter
21990Winter
Sage Thrasher
Number Year Season
12012Winter
11999Spring
Yellow-breasted Chat
Number Year Season
12010Winter
12010Fall
12009Summer
11999Summer
Waterbirds
Number Year Season
250,0001995Winter
180,0001991Winter
130,421 - 190,1221988Fall