ReadWBPHS: Prepare WBPHS data for index estimate calculation

In USFWS/AKaerial: Analysis of Alaska Region Aerial Survey Data

Prepare WBPHS data for index estimate calculation

Description

Load and adjust counts for WBPHS data to prepare for index estimate calculation

Usage

ReadWBPHS(full.data)

Arguments

full.data

An R data frame of observations in a given year of the survey

Details

This function takes standard greenlight data for the WBPHS (Waterfowl Breeding Population Habitat Survey, or North American) and prepares it for index estimate calculations. The function calls Cut9 to remove observations in Stratum 9 by a pre-defined longitudinal gradient for swans, cackling Canada geese, and greater white-fronted geese. These observations are removed prior to index estimation since they are included in other MBM coastal zone surveys (YKG). This function also adjusts the counts for each of 4 indices:

1. itotal - Indicated total. Singles doubled, pairs doubled, opens added, flkdrake 1-4 doubled, flkdrake 5+ added.

2. ibb - Indicated breeding birds. Singles doubled, pairs doubled, opens removed, flkdrake 1-4 doubled, flkdrake 5+ removed.

3. total - Total birds. Singles added, pairs doubled, opens added, flkdrake added.

4. sing1pair2 - Singles and pairs. Singles added, pairs doubled, opens removed, flkdrake removed.

5. flock - Flocks. Opens and flkdrakes of 5 or more.

In addition, due to inconsistencies in interpretation of the field protocol for data collection, open 1 and open 2 are changed to single 1 and pair 1, respectively, across the entire data set.

Value

The same data frame with additional index columns and modified counts, as well as modified Stratum 9 observations.

Author(s)

Charles Frost, [e-mail]

References

https://github.com/USFWS/AKaerial

USFWS/AKaerial documentation built on April 3, 2025, 4:06 p.m.