Observations define abundance scale.

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2 Observations define abundance scale. Burro Pasture Coyote Pasture Paisano Pasture

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5 Variance, Standard Error, Coefficient of Variation, Confidence Intervals

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21 Survey Cost Estimated cost/acre based on transect spacing (yds.), speed (mph), and hourly operations cost. All estimated costs per acre include 10% for non-survey time (i.e., between transect flight, gas, etc.). Estimated Cost = $0.18/acre

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23 23 Burnham et al Estimating of density from line transect sampling of biological populations Wildlife Monographs. CREEM WS

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27 Survey Design 1. Recommend at least observations per species 2. Recommend at least 20 transects 3. Determine % coverage (200 yds, 400 yds, 800 yds) 4. Systematically randomize lines within each sampling unit Trap Coyote Burro Paisano

28 Survey Design Obtaining reliable results from a distance sampling survey depends critically on good survey design. This relies upon the fundamental sampling principles of replication and randomization. Sufficient replicate lines or points ensure that variation in encounter rate can be adequately estimated. CREEM WS

29 Survey Design The lines or points should not be placed subjectively; rather a randomization scheme should be employed that gives all locations in the study region a known, non-zero probability of being covered by a transect (the coverage probability ). We recommend that a systematic survey design with a random start be used to afford better spatial coverage and lower variance. CREEM WS

30 Deer, Turkey, Nilgai Abundance Equations D = n 1 c Where: D = total deer n = # deer seen c = % coverage ((survey mi. * acres)/pasture acres) Unless stratified, the survey miles should include the good, the bad, and the ugly.

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37 Survey Design Partial surveys are not recommended.

38 Survey Design Complete surveys are recommended. Current surveys should be able to answer future questions.

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44 Stratification Global Survey season Division Ecoregion Stratum Pasture Sample Transect Observation Detection

45 What Is A Stratum Layer? A stratum layer is a distinct sampling unit that is uniquely named and surveyed separately. Stratum 1 Stratum 2 Stratum 3 Green Pasture 120 ac. Red Pasture 60 ac. Blue Pasture 80 ac.

46 What Is A Stratum Layer? Combine Small areas. Trap 20 ac. Combine Small areas Green 100 ac. Red 60 ac. Blue 80 ac. Green + Trap = 120 ac.

47 What Is A Global Layer? Multiple stratums that form a distinct sampling unit that is uniquely named and survey effort is combined. Stratum 1 Stratum 2 Black Pasture Yellow Pasture Global Layer = Green Pasture + Red Pasture + Blue Pasture + Black Pasture + Yellow Pasture Willacy County Stratum 3 Green Pasture Red Pasture Stratum 4 Stratum 5 Blue Pasture

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50 Stratification 38 Wildlife Management Units 50

51 Stratification 124 Pastures 51

52 Post-Stratification Burro Pasture Coyote Pasture To decrease non-survey effort, survey property with one continuous transect and hover at each fenceline to end and start new transect. Paisano If comfortable with ArcGIS, collect single length transect, clip transects with Pasture intersect tool, calculate length, use join and relate tool to label sightings and transects.

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54 Application of Survey Design GIS Facilitates In: Predetermining theoretical transect placement Systematically randomizing the transects (>20) Predetermining survey effort (60-70 observations) Enabling future surveys to be replicated Anticipating any problem segments It is critical that the lines be placed randomly with respect to the distribution of objects. Random line placement justifies the extrapolation of the sample statistics to the population of interest

55 Application of Survey Design Purchase XTools Package for ArcGIS Use Create Fishnet to design transect Use 400 yard transect spacing (50% coverage) Use boundary to determine transect angle Use pasture boundary to clip excess effort Load transects on Garmin Numvi via Mapwel

56 Application of Survey Design Use Mapwel ($100) to load Shapefiles onto Garmin GPS Use merge tool to load pasture boundary and transect shapefile Uniquely color each pasture and set zooming properties Set transect shapefile as major highway Load map to Garmin Nuvi. Print final survey map on 4x6 notecard and carry it with you during the survey. Mark off each transect as you complete them.

57 Equipment Arrangement Observer 1 Raw datasheet Observer 2 Pilot Navigator Database entry Garmin control Survey control 12V Outlet Important: Keep all lines clear of collective.

58 Survey Design Step 1. Use GIS or CKWRI Database to design transects Step 2. Use Mapwel ($100) to load Shapefiles onto Garmin GPS OR Step 1. Ask pilot to fly the area in a uniform pattern

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