2017 Kansas Pheasant Crowing Survey
Source: Kansas Department of Wildlife, Parks and Tourism
Excerpt from 2017 Report
Prepared by: Jeff Prendergast
INTRODUCTION
The Kansas Department of Wildlife, Parks, and Tourism (KDWPT) collects breeding population data for pheasant (Phasianus colchicus) by conducting crow counts throughout the pheasant range in the state. Measurable wild pheasant populations do not occur in south-east Kansas (Osage Cuestas Region). Pheasants are an extremely important wildlife resource for Kansas, and these indices help monitor population change through time.
METHODS
The survey period was from April 25 through May 15, 2017. Pheasant routes are ~20 mile transects, with at least 2 miles between each of the 11 stops. At stops, observers listen for 2 minutes and count all the audible 2-note (syllable) crows heard from male pheasants. The Pheasant Crow Survey Index (PCSI) is the mean number of crows per 2-minute stop for each route. The first stop begins 45 minutes before sunrise and continues through the last stop. Noise interference is taken into consideration, and data are censored if the observer feels noise is severely inhibiting their ability to count crows.
The results of the 2017 survey and comparisons to the 2016 data are presented in Table 1. Of the 65 established routes, 63 were assigned for 2017 (routes in Osage and Coffey counties are run only in even-numbered years), and 61 were successfully completed. Due to heavy rainfall throughout the initial survey period a one week extension was granted to allow for further data collection and 7 routes were surveyed during this time. Personnel assigned to these surveys are noted in Table 2. Range wide and regional trends since the survey’s 1997 initiation are shown in Figure 1. Location of routes within the state are shown in Figure 2.
Data Analysis
Given that samples are taken on permanently established routes, samples are not independent and thus a paired-sample t-test is used to draw inter-annual comparisons. A two-tailed test with an alpha level 0.10 was used to identify statistically significant differences between years at regional and statewide scales. Routes that do not have consistent observers are removed from analysis of inter-annual comparisons to remove observer bias in analysis.
Inverse Distance Weighting is a mapping technique that can be used to interpolate data between survey points, providing estimates to areas not surveyed. This technique has limitations at smaller scales (e.g., within counties and townships) because no habitat variables are included (only count data), but is useful for large-scale interpretation of statewide data for regional comparisons. Inverse Distance Weighting was used by assigning the route-specific PCSI to the centroid of each route. All sampled routes were used to extrapolate data throughout Kansas’ pheasant range (Figure 3). For comparison, the interpolated percent change of the PCSI from 2016 to 2017 is also included where observers are consistent (Figure 4).