bullfrog {AICcmodavg}

Bullfrog Occupancy and Common Reed Invasion

Description

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.

Usage

data(bullfrog)

Format

A data frame with 50 observations on the following 23 variables.

Location

a factor with a unique identifier for each wetland.

Reed.presence

a binary variable, either 1 (reed present) or 0 (reed absent).

V1

a binary variable for detection (1) or non detection (0) of bullfrogs during the first survey.

V2

a binary variable for detection (1) or non detection (0) of bullfrogs during the second survey.

V3

a binary variable for detection (1) or non detection (0) of bullfrogs during the third survey.

V4

a binary variable for detection (1) or non detection (0) of bullfrogs during the fourth survey.

V5

a binary variable for detection (1) or non detection (0) of bullfrogs during the fifth survey.

V6

a binary variable for detection (1) or non detection (0) of bullfrogs during the sixth survey.

V7

a binary variable for detection (1) or non detection (0) of bullfrogs during the seventh survey.

Effort1

a numeric variable for the centered number of sampling stations during the first survey.

Effort2

a numeric variable for the centered number of sampling stations during the second survey.

Effort3

a numeric variable for the centered number of sampling stations during the third survey.

Effort4

a numeric variable for the centered number of sampling stations during the fourth survey.

Effort5

a numeric variable for the centered number of sampling stations during the fifth survey.

Effort6

a numeric variable for the centered number of sampling stations during the sixth survey.

Effort7

a numeric variable for the centered number of sampling stations during the seventh survey.

Type1

a binary variable to identify the survey type, either minnow trap (1) or call survey (0) during the first sampling occasion.

Type2

a binary variable to identify the survey type, either minnow trap (1) or call survey (0) during the second sampling occasion.

Type3

a binary variable to identify the survey type, either minnow trap (1) or call survey (0) during the third sampling occasion.

Type4

a binary variable to identify the survey type, either minnow trap (1) or call survey (0) during the fourth sampling occasion.

Type5

a binary variable to identify the survey type, either minnow trap (1) or call survey (0) during the fifth sampling occasion.

Type6

a binary variable to identify the survey type, either minnow trap (1) or call survey (0) during the sixth sampling occasion.

Type7

a binary variable to identify the survey type, either minnow trap (1) or call survey (0) during the seventh sampling occasion.

Details

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.

Source

MacKenzie, D. I., Nichols, J. D., Lachman, G. B., Droege, S., Royle, J. A., Langtimm, C. A. (2002). Estimating site occupancy rates when detection probabilities are less than one. Ecology 83, 2248–2255.

Mazerolle, M. J., Perez, A., Brisson, J. (2014) Common reed (Phragmites australis) invasion and amphibian distribution in freshwater wetlands. Wetlands Ecology and Management 22, 325–340.

Mazerolle, M. J. (2015) Estimating detectability and biological parameters of interest with the use of the R environment. Journal of Herpetology 49, 541–559.

Examples

data(bullfrog)
str(bullfrog)