Grassland Bird Survey Protocol Sauvie Island Wildlife Area

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1 Grassland Bird Survey Protocol Sauvie Island Wildlife Area Project Objective: Help determine if native grassland bird species are benefiting from restoration of grassland/pasture habitats at the Sauvie Island Wildlife Area. Monitoring will measure changes in bird composition and density over time. Particular attention will be paid to identifying grassland bird species of conservation concern (e.g. Western Meadowlark, Streaked Horned Lark). Study site location information (also see maps at end of document) Site Name Latitude/Longitude* Comments Oak Island #1 (Blind Field) Start: N , W End: N , W The north end is the starting point & begins at the grazing exclosure Oak Island #2 (Rye Grass Field) Start: N , W End: N , W The start point is at a T-bar stake on the south end Grandma s Kitchen (Aaron site) Start: N , W End: N , W Start point is at a T-bar stake about 150 meters ahead & to the left if standing atop the levee. End point is to the north near a yellow pipe-gate North Unit Start: N , W End: N , W Start point is at north end (closest to ODFW residences) * Coordinates in decimal degrees A) Bird Surveys: Species presence and density Line-transect: Placement A 300m line-transect has been placed through the core of each of the 4 grassland/pastures that you will be monitoring to obtain a representative bird species sample. The start and end of each transect are marked with T-bar stakes (spray painted pink on top). At 50m intervals between the start and end stakes are wire flags placed in the ground to help you navigate along the transect. Cows often remove these flags so ODFW will keep some extras at the transect start stake and also may mark the ground with paint. Feel free to program the transect start and end point coordinates (see table above) into a GPS to help you quickly locate the transects. Surveys Walk along the line-transect at roughly 10m per minute (300m transect will take ~30 minutes). You may stop to observe birds but do not linger too long and do not leave transect to investigate a bird. If you cannot identify the species, write unknown on the datasheet. You may return to sections of the survey area after the transect is completed if you wish to investigate further (i.e., look for nest, ID species). Data collection: Fill in the survey and weather information at the top of the datasheet before beginning the survey. If possible, take a photo at the start of each transect for a visual vegetation record. Record all birds seen or heard in the field while walking the transect out to 300m on either side of the transect and, when you get to the end, 300m beyond the end stake. Do not count birds that are behind you when you are on the transect or while walking to the transect, include these under General Comments at the bottom of the sheet. Birds flying overhead that are obviously not utilizing the habitat (e.g. ducks transiting over the site) are recorded separately at the bottom of the datasheet. However, in some situations a bird flying over the sampling area may be using the habitat (e.g. swallow catching insects on the wing, Northern Harrier hunting). In these cases, it is OK

2 to record these data in the main table. If no birds were observed during a survey write none on the datasheet; this data still provides important information. Record if the bird is Male, Female, Juvenile, or Unknown, and whether the detection was Visual, Song, or Call. Record any incidental observation in the Species Contents section of the datasheet. Important information includes: signs of breeding behaviors such as carrying nesting material or insects, copulations, territorial displays, etc. Distance sampling techniques are used to estimate species densities by calculating species detectability. Detectibility is calculated by measuring the (perpendicular) distance of each bird to the line-transect. Estimate the distance to the best of your ability, and check the appropriate box (0-25m, 25-50m, m, m, m, >200m). To help aid in distance estimation, use the 50m distance between transect marker flags. We also have a rangefinder that you can use to estimate distance. The rangefinder will be kept at the ODFW office - please pick up and return from the office after your survey. Much of the time you will see birds ahead of you rather than perpendicular to you. You will need to estimate the distance these birds are from the transect perpendicular to from where they are, not from where you are. Any additional observations can be recorded under General Comments, such as other taxa observed in the survey area, or vegetation changes and/or conditions (e.g. condition of pasture, weeds, grazing effects, changes in vegetation, etc.). Over 30 species have been recorded on surveys but the most commonly detected species (~75% of detections) are listed in the table below. Data courtesy of ODFW (from Oak Island 1 & 2 sites data). Species % of total detections Savannah Sparrow 43.8% Song Sparrow 9.6% Common Yellowthroat 8.3% American Robin 8.3% Red-winged Blackbird 4.7% TOTAL 74.7% Timing: Conduct surveys once a week (minimum of once every two weeks) from late-march 1 until late July. Keep the amount of time between surveys as consistent as possible. Start survey 30min. before sunrise to 4 hours after. Do not conduct surveys during heavy rain or winds. If site #1 is sampled earlier than site #2 on a given visit, reverse that the next visit (visit site #2 first). This will reduce bias in changes in bird activity from early to late morning. Observers: We will work in pairs. Observer #1 will conduct the bird survey and will dictate what they are seeing/hearing to observer #2 whose main duty will be to record the data on the data sheet. Observer #1should be proficient in bird identification, both auditory and visual. If multiple people are conducting surveys, observers should survey sites an equal number of times to reduce observer bias. Gear list: Permit (get from Joe at Audubon or ODFW, place on dashboard of vehicle) Clip board (provided by Audubon) Appropriate clothing for surveying Camera (OK to use smart phone) Binoculars Data forms and protocol (provided by Audubon) Sun protection (sun hat, sun block) Rangefinder (optional) Pencil or pen Insect repellent GPS Unit (optional) 1 Check with ODFW staff at the start of each field season

3 B) Vegetation Sampling (only a subset of volunteers will need to collect this twice during the season please contact Joe Liebezeit if interested) Survey Line-transect: Sample vegetation every 50 meters along the 300m bird survey transect for a total of 6 sample points To offset effects of trampling on the transect route, sample vegetation 10 paces from transect (perpendicular). Alternate sides of transect sampled at each 50m flag point. Sample at least twice per season: Late April and late July (optimally once per month) Structure: Use the Robel Pole (Robel et al. 1970) to calculate vegetation height and vertical density (Visual Obstruction Reading). Collect 4 Robel Pole readings from the 4 cardinal directions (N, S, E, & W) using the rope to maintain a consistent distance from the pole. At the end of the rope, get eye-level with the vegetation (bend or lay down on ground), look at the pole and read (to the nearest cm) the lowest part of the pole that is visible. Composition: At each of the 6 locations where you will take the 4 Robel pole readings, also use the Daubenmire frame (Daubenmire 1959) to calculate ground cover. Toss the Daubenmire randomly on the ground near the Robel pole. Calculate percentages of grass, forbs, bare ground, litter, and woody vegetation within the Daubenmire frame. Forbs are any broad-leafed non-woody plants. Woody vegetation includes shrubs. Record moss in the bare-ground category but make a note on the data form what % of the bare-ground category was moss. Identify the dominant plant species Analysis: Average the 6 sample points measured to have one representative value for each variable Contact info: Joe Liebezeit Audubon Society of Portland Office: Cell: jliebezeit@audubonportland.org Justin Elliott Oregon Department of Fish and Wildlife Cell: (503) justin.j.elliott@state.or.us General Sauvie Island ODFW office number: (503)

4 Map and directions to sites: O Oak Island 1 site Directions from Sauvie Island Bridge: Take left on NW Sauvie Island Road, Take Right on Reeder Road, Take Left fork on Oak Island Road, Take right toward Sturgeon Lake boat ramp. Parking on South side of road.

5 Oak Island 2 site (rye grass field) Directions: same as Oak Island #1 but continue North on Oak Island Road until you reach gate. You will need to get the key to open the gate and continue another ¼ mile.

6 Grandma s Kitchen Directions from Sauvie Island Bridge: Take left on NW Sauvie Island Road, Take Right on Reeder Road and continue on it around the east side of Sturgeon Lake. Take left on Rentenaar Road. At the end of this road is Grandma s Kitchen. Transect is just over the levee from the end of Rentenaar Road. North Unit Directions: Same as Grandma s Kitchen except stay on Reeder Road and continue north until you get to the dead end, as this is the North Unit parking lot. North Unit transect lies just west of the two ODFW residences. To reach the starting point, hop over the metal gate on the west end of the lot and walk southwest through the pasture about a ¼ mile. The 0 meter t-post is about 100 yards past the barn. After the survey it s easiest to just walk over to Reeder Rd. and follow it back to the parking lot.