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PROTOCOL 2:
Hybrid Index
For this part of GOWAP, you will choose one or more pages from your state Delorme Atlas
or Canadian topo map and conduct 10-minute point counts in suitable Golden-winged Warbler
habitat. The object of this protocol is to record the occurrence of golden-wings,
blue-wings, and hybrids in order to map the hybrid zone of these species. An essential
step towards long term management of Golden-winged Warblers depends on locating key
"safe haven sites" where hybridization is rare.
On each Delorme page or topo you will complete 20 point counts for the Hybrid Index.
Since these point counts should only be conducted in the morning hours, it should take at
least two mornings to complete 20 points.
Time of Day to Complete Study
Identification must be based on visual ID of the study species and, therefore, should
not begin until there is sufficient light to recognize subtle differences in plumage. We
recommend that you start your surveys between 5:15 and 7:00 am. Counting must end by the
following times:
By 11:00 am before May 20
By 10:30 am between May 20 and May 31
By 10:00 am between May 31 and June 15
Please do not count in the following conditions:
1. When wind keeps small twigs in constant motion
2. When temperature is below 32 F or above 80 F
3. During any precipitation
 Select Study Sites
- Divide your Delorme page or Canadian topo map into four quadrants; southeast, southwest,
northeast, and northwest.
- You will conduct 5 point counts in each quadrant (total of 20 points per page),
selecting any starting point along a road where you have good visibility and are
surrounded by suitable breeding habitat for Golden-winged Warblers.
- After conducting the first point count, drive to the next area of suitable habitat. Make
sure that each point is at least a quarter mile apart so you don't count the same birds
twice. This is not a random point selection, so if you have prior knowledge of where
golden-wings are breeding, you can start your point counts in this area.
- If you are surveying along a trail or power line right of way, be sure to walk at least
a quarter mile between points as well.
Field Surveys
- At each point you will conduct a standard 10-minute point count.
- Begin by listening and scanning for any singing Golden-winged or Blue-winged warblers.
Then play one complete side of the GOWAP tape. This tape has songs and periods of silence
at specific intervals so you only have to press play and let it run for the entire 10
minute count.
30-sec silence
1-min GWWA Type I
30-sec silence
1-min BWWA Type I
30-sec silence
1-min BWWA Type II
30-sec silence
1-min GWWA Type I
30-sec silence
1-min BWWA Type 1
30-sec silence
1-min BWWA Type II
1-min silence
- While the tape is playing and during the periods of silence, make sure to search in all
directions for golden-wings, blue-wings, and hybrids. Be aware that individuals may fly in
from great distances, may approach silently, or may fly back and forth past the tape
recorder. Your goal at each point is to determine the total number of individuals of
each parental and hybrid type detected during the total 10-minute period.
- In order to record a bird as being present during your point count, you must get a
visual ID. This is extremely important since golden-wings and blue-wings have the
ability to sing each other's songs.
- If possible, you may want to conduct your point counts with two observers so you can
look in both directions at once and try to identify every bird that comes into the tape.
- Make sure to note the site characteristics; see the Data
Form instructions.
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