2014 Drumming Survey Results
During the spring 2014 wild turkey hunting season, DEC conducted the eighth annual Ruffed Grouse Drumming Survey. This survey asks turkey hunters to record the number of grouse they hear drumming while afield. The primary purpose of the survey is to monitor the number of birds drumming per hour (i.e., the drumming rate). Changes in the drumming rate illustrate trends in the grouse population when viewed over time and will provide insight into statewide distributions for this popular game species as habitats change both locally and on a landscape scale.
You can view, print, or download the complete 2014 Ruffed Grouse Drumming Survey Report (PDF) (535 kB).
We thank all the hunters that participated in the Ruffed Grouse Drumming Survey during the 2014 season.
Results from the 2014 Season
During the 2014 season, 210 hunters participated in the Ruffed Grouse Drumming Survey. Survey participants reported data from over 1,300 hunting trips across the state, from the lower Hudson Valley in the south, to the Adirondacks and St. Lawrence Valley in the north, and the Lake Plains and Allegheny Plateau in far western New York. They spent over 5,000 hours afield and observed almost 1,000 grouse. Some general findings from the 2014 season include:
- Hunters participating in the survey averaged about 24 hours afield during the 2014 season. They took about 6 trips afield for the season and spent almost 4 hours afield per trip.
- Survey participants averaged about 4.5 grouse observed per hunter for the 2014 season and had to spend 4.5 hours afield in order to hear one grouse drumming.
- About 60% of all survey effort took place during the first two weeks of May and the drumming rate (grouse drumming/hour) was highest during this portion of the month.
- Overall, there was far more effort expended in the southern zone (almost 90% of the total), but the drumming rate was similar between the northern and southern zones (0.24 vs. 0.21 grouse drumming/hour).
- Significantly more effort was expended, and more grouse were observed, on private land than public land; however, public land had a slightly higher drumming rate.
- Survey effort was distributed across major geographic regions of New York State (28% in southeastern NY, 12% in northern NY, 59% in central and western NY). We observed the highest drumming rate in DEC Region 9 in western NY (0.31 grouse drumming/hour) followed by DEC Region 7 in central NY (0.27 grouse drumming/hour). The drumming rate was below the statewide average in DEC regions 3, 4, 6, and 8 (0.05, 0.17, 0.16, and 0.10 grouse drumming/hour, respectively).
- The drumming rate was highest in the St. Lawrence Valley Ecozone (0.40 grouse drumming/hour), followed by the Adirondacks-Tug Hill and Appalachian Hills and Plateau ecozones (0.31 grouse drumming/hour). The drumming rate was below the statewide average in the Mohawk Valley-Hudson Valley-Taconic Highlands, Lake Plains, and Catskills-Delaware Hills ecozones.
Comparing 2014 to Previous Seasons
- Since this survey started in 2007, about 650 turkey hunters took over 9,200 trips afield and spent over 35,000 hours recording their grouse observations. Over the past eight years, grouse numbers increased, peaked around 2009, and have declined since. Whether this is a result of some cyclical fluctuation or is related to the influence of habitat and weather on nest and brood success is unknown.
- From 2013 to 2014 the number of survey participants, and the number of trips and hours afield decreased, but survey effort in 2014 was still above the average from 2007-12. Due to concerns about small sample sizes in some Wildlife Management Unit aggregates, particularly in northern NY, in 2013 we solicited additional participants from hunters currently enrolled in the Grouse and Woodcock Hunting Log program in the fall. This resulted in over 70 new participants in the spring 2013 drumming survey and improved our ability to estimate drumming rates at the WMU aggregate level (e.g., St. Lawrence Valley).
- From 2013 to 2014 the drumming rate decreased from 0.23 to 0.22 grouse drumming/hour, but this decrease was not statistically significant. The amount of time spent afield to hear one grouse drumming was similar between years.
- Similar to the decrease in drumming rate from 2013 to 2014, both the number of grouse observed/participant and grouse observed/trip decreased between years.
- Most of western New York (Lake Plains, Appalachian Hills & Plateau) saw an increase in the drumming rate from 2013 to 2014, but the drumming rate in the Lake Plains was still well below the statewide average. The drumming rate in much of eastern New York declined 30-45% from 2013 to 2014, but the rates in the Adirondacks and St. Lawrence Valley were still above the statewide average.
- Annual variation in grouse abundance is likely a result of variation in weather, including spring temperature and rainfall and winter snow conditions, and food availability during the summer and fall (e.g., hard and soft mast, insects). Data from the U.S. Department of Agriculture National Agricultural Statistics Service indicate that from April 1 through the end of May 2013, rainfall totals were above normal statewide. This, combined with severe winter conditions in many areas, may have negatively affected nest and brood success and overwinter survival.
- In areas with a lack of the early successional habitats on which this species depends (e.g., Lake Plains, lower Hudson Valley), grouse, their nests, and young are more vulnerable to predation and other limiting factors, thus we tend to observe lower drumming rates in these areas. Over the past eight years, the Wildlife Management Units with the highest drumming rates are those that have a landscape with a greater proportion of the early successional habitats (e.g., shrubland, young forests) that grouse depend upon than the units with below-average drumming rates. Increasing the number of survey participants in some WMUs will paint a more accurate picture of grouse distribution and abundance statewide.
Drumming Survey vs. Grouse Hunting Log
- At the statewide scale the drumming rate from the spring survey and the flush rate from the Grouse Hunting Log conducted during the fall are correlated (i.e., when we observe an annual change in the drumming rate, we see a similar change in the flush rate). Based on this, we anticipate that the flush rate during the upcoming 2013-14 hunting season will be similar to or slightly below last fall (0.77 grouse flushed/hour in 2013-14), and below the long-term average flush rate (about 1 bird/hour).
- When we attempt to link drumming rates with flush rates at smaller scales, the results are often inconsistent; drumming rates do not consistently predict flush rates at the ecozone or WMU aggregate level. Part of the reason for this may be the unpredictability of the nesting season (i.e., percent of nests that are successful, survival of broods) between the time the drumming survey is conducted in the spring and the time the grouse log is conducted during the fall. It is important to note that this is based on only eight years worth of data and the results of the drumming survey and grouse hunting log may be correlated at the ecozone or WMU aggregate level over the long term.