Sample Data for the DISTANCE sampling course Amakihi (Point transect with covariates) - ships with the DISTANCE program. See Auk paper in director for more details The example data were collected as part of a larger study to assess a Palila (Loxioides bailleuli) translocation experiment on the island of Hawaii (Fancy et al. 1997). Multi-species point- transect surveys were performed at seven survey periods between July 1992 and April 1995. There were 41 point-count stations, though they were not all surveyed in some survey periods. To illustrate the use of MCDS methods, we selected the most commonly recorded species, the Hawaii Amakihi (Hemignathus virens), a generalist Hawaiian honeycreeper. The main goal of the analysis was to estimate Amakihi density during each of the survey periods, which are considered temporal strata. - covariates are Observer (OBS), minutes after sunrise (MAS), or hours after sunrise (HAS) The HAS covariates will be treated as a categorical variable while MAS will be treated as a continuous covariate. Dolphins (Line transect, double observer) - from WISP package Harbour Porpoise sample data from 1994 SCANS survey 98 transect lines, 1 km half-width of varying lengths (km) Record distance to group, group size, sex (groups are composed of a single sex), and exposure (a detectability factor related to weather and other attibutes) Total survey region is 889600 km2 Example-Line - ships with the DISTANCE program - hypothetical data illustrating a simple line transect analysis Example-Line-Stratification - ships with the DISTANCE program - hypothetical data illustrating geographic stratification in line transects Example-point - ships with the DISTANCE progra - hypothetical data illustrating a simple point transect analysis Elephant Dung density (Line transect; Use of multipliers) http://www.wcsmalaysia.org/analysis/Elephant_dung_DISTANCE.htm In 2001, WCS Indonesia Program estimated the elephant population of Bukit Barisan Selatan National Park (BBSNP) in Sumatra, Indonesia, from dung surveys (Hedges et al, 2005). The field research comprised three components: dung production rate estimation based on observations of 12 captive elephants ranging freely in the nearby Way Kambas National Park; dung disappearance time based on monitoring 1302 dung piles in BBSNP for 18 months prior to the survey of dung density; and dung pile density estimated by line transect surveys. GolfTees - ships with DISTANCE - GolfTees with two observers taken from Borchers (2002) - Two colors (green=0 and yellow=1) placed in clusters of 1-8 in a survey region of 1680 m2. Tees were either exposed above grass(exposed=1) or not exposed (exposed=0). 11 8 m wide strips (w=4 m) and totaled 210 m in length. Two sets of teams surveyed and are treated as 2 observers. Grosbeak (Point transect) - Blue grosbeaks (Guiraca caerulea) in Georgia, USA. Points (1-2) were randomly placed in 39 agricultural fields that were being included in a longleaf pine (Pinus palustris) restoration program. http://coopunit.forestry.uga.edu/quant_cons_book/companion/chapter9/index.html HouseWren (Point Transect) - ships with DISTANCE program. - 10 study blocks of 16 ha/ 14-16 points in each block along 30 km of South Platte River - 4 observers visited each point. Pheasants (Line transect) - Great Argus Pheasants Within an 800-ha study area, 144 line transects were placed, each 2,200-m long. Observers walked each transect and detected Argus present, if any. During the study, birds were detected on 45 of the 144 transects. http://coopunit.forestry.uga.edu/quant_cons_book/companion/chapter9/index.html Orangatans (Line transect; stratification) http://www.wcsmalaysia.org/analysis/O-u_nests_DISTANCE.htm WCS Malaysia has studied orang utan in Batang Ai National Park in Sarawak for some years. Like most great apes, orang utan build a simple nest of broken branches to sleep at night, and sometimes build a day-time nest too if they take a siesta. If we assume that there is a simple relationship between the number of nests and the number of orang utan in our study area, we can use the number of nests to compare populations between sites or to detect declines or increases in the population over time. Transect surveys were used to estimate the density of nests in the park. Tortiose - Plastic tortoise data set collected using line transect sampling. - Available in the wisp package (tortoise.samp.lt) - 3 transects, 1000 m in length each. - Truncation distance is 50 m on each side of the line during the survey - Total area is unknown, so just estimate density.