Proposed Point Grey Tidal Marsh Project Standwatch Bird Surveys Spring/Summer 2014

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1 18 th Floor, 4730 Kingsway Burnaby, BC V5H 0C6 T: F: hemmera.com Proposed Point Grey Tidal Marsh Project Standwatch Bird Surveys Spring/Summer 2014 Report Date Survey Dates & Times Weather & Tidal Conditions Survey Areas October 30, 2014 Twenty-three (23) standwatch bird surveys were conducted from April 22, 2014 to September 10, The objective of these surveys was to characterize waterbird use of the proposed Point Grey Tidal Marsh Project site, with an emphasis on shorebirds. These surveys focused on peak migration times of Western Sandpiper, as this species typically comprises the vast majority of shorebirds stopping over in the Fraser River Estuary during migration. Three phases of shorebird migration were assessed between April 22, 2014 and September 10, 2014: 1. Northward Migration: Surveys were conducted every three days between April 22, 2014 and May 16, 2014 (nine surveys total) 2. Southward Adult Migration: Surveys were conducted every three days between July 5, 2014 and July 26, 2014 (eight surveys total) 3. Southward Juvenile Migration: Surveys were conducted every five days between August 14, 2014 and September 10, 2014 (six surveys total) Survey times were scheduled with mudflat 1 stations centered on peak daytime low tides. Survey direction was alternated each survey (east to west vs. west to east) to reduce potential bias. All surveys were conducted during wind speeds less than 25 km/hour. With the exception of light rain on May 10 and August 29, all surveys were conducted in the absence of rain. As mudflat surveys were centered on peak daytime low tides, the first half of each survey was conducted during a falling low tide, with the latter half of each survey conducted during a rising low tide. Port Metro Vancouver s (PMV s) Habitat Enhancement Program Proposed Point Grey Tidal Marsh, Vancouver, BC. The proposed enhancement site is located on the north side of the North Arm of the Fraser River, south of Pacific Spirit Regional Park. The site was divided into six different survey areas, including four mudflat standwatch stations (Control West, Control East, Treatment West, and Treatment East) and two standwatch stations in existing marsh (Marsh West and Marsh East) (Figure 1). 1 The term mudflat(s) henceforth refers to all treatment and control stations as a single entity unless defined otherwise.

2 Survey Team Scope of Work Survey Methods Results Andrew Venning, Biologist (Hemmera); Toby St. Clair, Biologist (Hemmera); Vanessa Sadler, Biologist (Hemmera) As part of Port Metro Vancouver s Habitat Enhancement Program, the creation of a brackish tidal marsh is proposed at the Point Grey Booming Grounds site in Vancouver, B.C. The historic booming grounds where the project will be located consist of mudflats which have been impacted to some extent by years of log boom storage (e.g., woodwaste, sediment compaction and scoured channels from prop wash). The project will help restore tidal marsh habitats within the North Arm of the Fraser River, where considerable areas of natural brackish marsh have been lost over the past 70 to 80 years through land development activities. The proposed project is located between a natural brackish marsh to the southeast and extensive mudflats to the northwest. In order to better understand bird use of mudflats overlapping with the project site, standwatch bird surveys were conducted between April 22, 2014 and September 10, 2014 during peak times of shorebird migration. The primary objective of these surveys was to document shorebirds using the mudflats within the proposed Point Grey Tidal Marsh Project site and within adjacent mudflat control sites. Although shorebirds were the focal species group for mudflat standwatch surveys, use by all bird species was also part of this survey work. The existing adjacent marsh to the southeast was also surveyed to provide insight into the value of the proposed new marsh habitat for all bird species present. A single surveyor conducted 30-minute standwatches within each station illustrated in Figure 1. All detectable bird species were documented. Binoculars and spotting scope were used to identify and count birds detected visually; bird vocalizations were also identified and counted. To ensure identification and count accuracy on mudflats, the observer was positioned in the center of the station, halfway between the tideline and the existing marsh to the northeast (see Photo 1). Large shorebird flocks were approached when necessary. Standwatches in existing marsh were conducted from locations illustrated in Figure 1. For each bird documented, the following information was recorded: species, number, time, distance from existing northeast marsh (for mudflat stations)/distance from observer (for existing marsh stations), and behavior. Mudflats Cumulative abundance of each species documented on mudflats is presented in Table 1. The five most abundant species accounted for 72% of all birds observed on mudflats: Western Sandpiper (n=6041), Green-winged Teal (n=2684), Dunlin (n=2243), Mallard (n=1536), and Ring-billed Gull (n=1276). Shorebirds (n=9198) were the most abundant species group observed, followed by Waterbirds (n=5956) and (n=2065), respectively. At control sites, shorebirds were the most abundant species group, followed by dabbling, and gulls and terns, respectively (Figure 2). The same relative trend was observed at treatment sites, with a much larger difference observed between shorebirds and dabbling (Figure 3). were the most abundant species group at Treatment West, followed closely by shorebirds, and gulls and terns, respectively (Figure 4). Shorebirds were the most abundant species group at Treatment East (adjacent existing marsh), followed by dabbling, and geese, respectively (Figure 5).

3 Nine shorebird species were observed on the mudflats: Western Sandpiper (n=6041); Dunlin (n=2243); Unidentified Shorebird (n=523); Killdeer (n=122); Black-bellied Plover (n=108); Least Sandpiper (n=73); Unidentified Caladris (n=73); Greater Yellowlegs (n=9); Semipalmated Plover (n=3); Lesser Yellowlegs (n=2); Spotted Sandpiper (n=1). Shorebirds accounted for 48% of all birds observed on mudflats. Western Sandpipers were most commonly observed in treatment stations, adjacent the existing marsh; fewer Western Sandpipers were observed in control stations farther from the existing marsh (Figure 6). Dunlin showed the opposite relationship, most commonly observed in control stations, with fewer observations in treatment stations (Figure 6). Large flocks (i.e., >1000 birds) of shorebirds were observed infrequently at Point Grey (Table 2). During northward migration, a relatively large flock was observed only on April 28 (n=3781), and on three survey days none were observed. During southward adult migration, fewer shorebirds were observed relative to other migration phases; the highest number recorded was 162 and on three survey days none were observed. During southward juvenile migration, a relatively large flock was observed only on August 24 (n=4369) (see Photos 2 and 3); for the remainder of this migration phase shorebirds were observed in relatively small numbers. Two Osprey pairs were observed nesting on pilings in Treatment West and Treatment East (Figure 1, Photos 4 and 5). Based on the spring/summer surveys, it appears that each nesting pair successfully raised and fledged one young in Osprey were most commonly observed in treatment stations; observation frequency increased with proximity to existing marsh (Table 1). Existing Marsh Cumulative abundance of each species documented in existing marsh (both existing marsh stations pooled) is presented in Table 3. The five most abundant species accounted for 65% of all birds observed in existing marsh: Marsh Wren (n=167), Redwinged Blackbird (n=115), Violet-green Swallow (n=70), Barn Swallow (n=65), and Northwestern Crow (n=49). (n=430) were the most abundant species group observed, followed by Swallows (n=135) and Other Passerines (n=51), respectively (Figure 7). Visibility in existing marsh stations was limited (see Photo 6) and a large proportion of observations consisted of vocalizations. Outside of the breeding season (i.e., after July 1 st ) vocalizations were minimal and thus detectability in existing marsh stations was relatively low. Numbers presented represent minimum numbers of birds observed.

4 Tables Table 1. Cumulative abundance of bird species observed on mudflats at Point Grey during spring/summer 2014 standwatch bird surveys, with shorebird species shown in bold; Vancouver, BC. Species Group Common Name Latin Name Shorebirds Western Sandpiper Control West Control East Station Treatment West Treatment East Grand Total Calidris mauri Green-winged Teal Anas crecca Shorebirds Dunlin Calidris alpina Mallard Anas platyrhynchos Ring-billed Gull Larus delawarensis Northern Pintail Anas acuta Geese Canada Goose Branta canadensis Shorebirds Unidentified Duck Diving Unidentified Shorebird American Wigeon Anas americana Unidentified Duck Caspian Tern Hydroprogne caspia Unidentified Gull Larus sp Bonaparte's Gull Glaucous-winged Gull Chroicocephalus philadelphia Larus glaucescens Bufflehead Bucephala albeola Shorebirds Killdeer Charadrius vociferus Other Passerines Shorebirds Northwestern Crow Black-bellied Plover Corvus caurinus Pluvialis squatarola Swallows Barn Swallow Hirundo rustica Herons Great Blue Heron Ardea herodias Raptors Osprey Pandion haliaetus Diving Red-breasted Merganser Mergus serrator Shorebirds Least Sandpiper Calidris minutilla Shorebirds Unidentified Caladris California Gull Larus californicus Gadwall Anas strepera

5 Species Group Common Name Latin Name Raptors Bald Eagle Haliaeetus leucocephalus Control West Control East Station Treatment West Treatment East Grand Total Raptors Peregrine Falcon Falco peregrinus Cormorants Shorebirds Cormorants Mew Gull Larus canus Unidentified Cormorant Greater Yellowlegs Savannah Sparrow Double-crested Cormorant Tringa melanoleuca Passerculus sandwichensis Phalacrocorax auritus Marsh Wren Cistothorus palustris Shorebirds Red-winged Blackbird Unidentified Swallow American Goldfinch Semipalmated Plover Agelaius phoeniceus Spinus tristis Charadrius semipalmatus Shorebirds Lesser Yellowlegs Tringa flavipes Northern Shoveler Anas clypeata Pacific-slope Flycatcher Empidonax difficilis Song Sparrow Melospiza melodia Violet-green Swallow Tachycineta thalassina Belted Kingfisher Megaceryle alcyon Blue-winged Teal Anas discors Brewer's Blackbird Cedar Waxwing Euphagus cyanocephalus Bombycilla cedrorum Cinnamon Teal Anas cyanoptera European Starling Sturnus vulgaris Franklin's Gull Leucophaeus pipixcan Shorebirds Spotted Sandpiper Actitis macularius Unidentified Hummingbird Grand Total

6 Table 2. Daily abundance of shorebirds observed on mudflats at Point Grey during spring/summer 2014 standwatch bird surveys; Vancouver, BC. Date Number Migration Phase April April April May May May May May May July July July July July July July July August August August August September September Northward Southward Adult Southward Juvenile Table 3. Cumulative abundance of species observed in existing marsh (both stations pooled) at Point Grey during spring/summer 2014 standwatch bird surveys; Vancouver, BC. Species Group Common Name Latin Name Number Marsh Wren Cistothorus palustris 167 Red-winged Blackbird Agelaius phoeniceus 115 Swallows Violet-green Swallow Tachycineta thalassina 70 Swallows Barn Swallow Hirundo rustica 65 Other Passerines Northwestern Crow Corvus caurinus 49 Song Sparrow Melospiza melodia 37 Unidentified Swallow - 31 American Goldfinch Spinus tristis 22 Raptors Bald Eagle Haliaeetus leucocephalus 20 Mallard Anas platyrhynchos 15 Geese Canada Goose Branta canadensis 13

7 Species Group Common Name Latin Name Number Unidentified Hummingbird - 12 Unidentified Swift - 10 Unidentified Duck Unidentified Duck - 10 Hummingbirds Anna's Hummingbird Calypte anna 8 Glaucous-winged Gull Larus glaucescens 8 Cedar Waxwing Bombycilla cedrorum 7 American Robin Turdus migratorius 6 Other Virginia Rail Rallus limicola 6 Black-capped Chickadee Poecile atricapillus 6 Herons Great Blue Heron Ardea herodias 4 Spotted Towhee Pipilo maculatus 4 Raptors Red-tailed Hawk Buteo jamaicensis 3 Chestnut-backed Chickadee Poecile rufescens 3 Unidentified Gull Larus sp. 3 Purple Finch Haemorhous purpureus 2 Diving Red-breasted Merganser Mergus serrator 2 Raptors Osprey Pandion haliaetus 2 Golden-crowned Kinglet Regulus satrapa 2 Raptors Sharp-shinned Hawk Accipiter striatus 1 Ring-billed Gull Larus delawarensis 1 Unidentified Passerine - 1 Bewick's Wren Thryomanes bewickii 1 Shorebirds Killdeer Charadrius vociferus 1 Raptors Peregrine Falcon Falco peregrinus 1 Pacific-slope Flycatcher Empidonax difficilis 1 Other Passerines Common Raven Corvus corax 1 Common Yellowthroat Geothlypis trichas 1 Downy Woodpecker Picoides pubescens 1 Other Passerines European Starling Sturnus vulgaris 1 Black-headed Grosbeak Pheucticus melanocephalus 1 Grand Total 714

8 Figures Figure 1. Point Grey Proposed Tidal Marsh Project Standwatch bird monitoring stations assessed during spring/summer 2014 surveys; Vancouver, BC.

9 Cumulative Number of Birds Observed Figure 2. Abundance of species groups observed at Point Grey control (mudflat) sites during spring/summer 2014; Vancouver, BC. Cumulative Number of Birds Observed Figure 3. Abundance of species groups observed at Point Grey treatment (mudflat) sites during spring/summer 2014; Vancouver, BC.

10 3500 Cumulative Number of Birds Observed Figure 4. Abundance of species groups observed at Point Grey treatment west (mudflat) during spring/summer 2014; Vancouver, BC Cumulative Number of Birds Observed Figure 5. Abundance of species groups observed at Point Grey treatment east (mudflat), adjacent existing marsh, during spring/summer 2014; Vancouver, BC.

11 3500 Cumulative Number of Birds Observed Western Sandpiper Dunlin 0 Control West Control East Treatment West Treatment East Station Figure 6. Abundance of Western Sandpiper and Dunlin observed on mudflats at Point Grey during spring/summer 2014; Vancouver, BC. 500 Cumulative Number of Birds Observed Figure 7. Abundance of species groups observed at Point Grey existing marsh stations during spring/summer 2014; Vancouver, BC.

12 Photos Photo 1. Observer s view of mudflats at Point Grey, facing northwest, treatment stations are in foreground and control stations in background; Vancouver, BC (May 16, 2014). Photo 2. Western Sandpiper feeding on mudflats in treatment stations at Point Grey; Vancouver, BC (August 24, 2014).

13 Photo 3. Peregrine Falcon (right) hunting Western Sandpipers (left) in treatment stations; view facing southward to river; Vancouver, BC (August 24, 2014). Photo 4. Osprey nesting at Point Grey; Vancouver, BC (May 16, 2014).

14 Photo 5. Osprey adult (left) and young (right) on nest at Point Grey; Vancouver, BC (August 19, 2014). Photo 6. Observer s view of existing marsh at Point Grey, facing southwest; Vancouver, BC (May 16, 2014).