This is a data set from Mazerolle et al. (2014) on the occupancy of Bullfrogs (Lithobates catesbeianus) in 50 wetlands sampled in 2009 in the area of Montreal, QC.
data(bullfrog)A data frame with 50 observations on the following 23 variables.
Locationa factor with a unique identifier for each wetland.
Reed.presencea binary variable, either 1 (reed present) or 0 (reed absent).
V1a binary variable for detection (1) or non detection (0) of bullfrogs during the first survey.
V2a binary variable for detection (1) or non detection (0) of bullfrogs during the second survey.
V3a binary variable for detection (1) or non detection (0) of bullfrogs during the third survey.
V4a binary variable for detection (1) or non detection (0) of bullfrogs during the fourth survey.
V5a binary variable for detection (1) or non detection (0) of bullfrogs during the fifth survey.
V6a binary variable for detection (1) or non detection (0) of bullfrogs during the sixth survey.
V7a binary variable for detection (1) or non detection (0) of bullfrogs during the seventh survey.
Effort1a numeric variable for the centered number of sampling stations during the first survey.
Effort2a numeric variable for the centered number of sampling stations during the second survey.
Effort3a numeric variable for the centered number of sampling stations during the third survey.
Effort4a numeric variable for the centered number of sampling stations during the fourth survey.
Effort5a numeric variable for the centered number of sampling stations during the fifth survey.
Effort6a numeric variable for the centered number of sampling stations during the sixth survey.
Effort7a numeric variable for the centered number of sampling stations during the seventh survey.
Type1a binary variable to identify the survey type, either minnow trap (1) or call survey (0) during the first sampling occasion.
Type2a binary variable to identify the survey type, either minnow trap (1) or call survey (0) during the second sampling occasion.
Type3a binary variable to identify the survey type, either minnow trap (1) or call survey (0) during the third sampling occasion.
Type4a binary variable to identify the survey type, either minnow trap (1) or call survey (0) during the fourth sampling occasion.
Type5a binary variable to identify the survey type, either minnow trap (1) or call survey (0) during the fifth sampling occasion.
Type6a binary variable to identify the survey type, either minnow trap (1) or call survey (0) during the sixth sampling occasion.
Type7a binary variable to identify the survey type, either minnow trap (1) or call survey (0) during the seventh sampling occasion.
This data set is used to illustrate single-species single-season
occupancy models (MacKenzie et al. 2002) in Mazerolle (2015). The
average number of sampling stations on each visit was 8.665714, and was
used to center Effort on each visit.