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Ruffed Grouse Population Management

Reasons for Population Changes

Ruffed grouse in the snow
Photo courtesy of CT DEP.

Ruffed grouse populations in New York have been drastically declining over the past 40 years. Several different survey efforts (U.S. Geological Survey's Breeding Bird Survey, New York State Breeding Bird Atlas) support what grouse hunters have know for a long time. Breeding Bird Survey data indicate that ruffed grouse populations in New York have declined by more than 75% since the 1960s, or about -4.7%/year. The primary reasons for population declines are habitat quantity and quality. During the 1960s and 70s, many agricultural lands that had been abandoned were reverting to young forests-ideal habitat for ruffed grouse. Today, these forests have reached maturity, a less than ideal condition for grouse, woodcock, and other birds that require early successional habitats.

Greatest population densities for grouse tends to be:

  • areas where there is good habitat such as agricultural areas recently abandoned (within the last 10-20 years);
  • areas with active timber management (particularly "even-aged" management such as clear cuts); and
  • areas where habitats are maintained in an early successional stage due to environmental factors such as soil type, moisture, and natural disturbance (e.g., storms, fire, disease).

Population Trends

Having previously used New York statewide grouse harvest estimates as an index to grouse populations, we haven't noticed a 10-year cycle population trend such as found in Michigan, Wisconsin, and Minnesota. These states have surveyed over large geographic scales (statewide and intrastate regions), though it is unclear whether the same results can be found at smaller scales (town or county). Alternatively, there may be population cycles operating at a geographic scale larger (northeastern U.S.) or smaller (St. Lawrence Valley) than currently being measured.

It is still unclear on exactly what drives these cycles, but many scientists think it involves a complex interaction of:

  • habitat quality (stem density, food distribution, and abundance)
  • predation on nests and broods
  • weather
  • insect damage (tree-defoliating tent caterpillars)
  • other miscellaneous factors

Predation Impact

Predation can play a role in limiting grouse populations; however, it is more likely that the problem is poor habitat quality that makes birds, their nests, and broods more vulnerable to predation. Grouse have evolved behaviors and reproductive strategies to cope with predation, but in highly fragmented landscapes predators may be more efficient in finding grouse and their nests. This is particularly true for nest predators such as raccoons, skunks, and opossums. In areas with poor habitat quality, such as low stem densities or poor overhead cover, grouse and chicks may be more vulnerable to avian predators such as hawks and owls. Large predators, such as coyotes, may be impacting game species on a local scale, but it is unclear whether they are affecting populations in large regions of New York or statewide.

Grouse Research

Ruffed grouse with radio collar
Ruffed grouse with radio collar

In an effort to answer some of the common questions about grouse populations, DEC coordinates two surveys and collects grouse parts from hunter-killed birds. The Cooperator Ruffed Grouse Hunting Log asks grouse hunters to record the number of birds flushed per hour of hunting effort. The Ruffed Grouse Drumming Survey asks turkey hunters to record all drumming male grouse observed while they are afield during the month of May. We hope that, when viewed over time and various spatial scales, both of these surveys will help us identify trends in grouse distribution and abundance. The grouse parts collection allows us to evaluate the age and sex composition of the harvest and estimate recruitment (number of young per adult female) for different regions of the state. To learn more or to participate, e-mail us or call (518) 402-8883.

In 2007, DEC initiated a cooperative research project with SUNY Environmental Science & Forestry to determine fall-winter survival and mortality of ruffed grouse in two areas of New York State with relatively high hunting pressure and different degrees of habitat fragmentation. This study was the first assessment of ruffed grouse survival and harvest mortality in New York in more than 50 years. We monitored fall-winter survival of 169 radio-marked ruffed grouse at two study areas in New York differing in forest age and composition. Fewer than 11% of radio-marked birds were harvested, and seasonal survival was similar at the two study areas in both study years (0.38 and 0.51, 2007-08; 0.48 and 0.48, 2008-09). Predation, particularly by raptors, was the largest source of mortality, but locations of predation events were not associated with forest age or configuration within 300 meters. We found no evidence to support a reduction in harvest limits, although our harvest estimates may have been biased low.

Landowner Involvement

Restoring habitat usually means cutting timber. This has an indirect benefit of generating revenue for the landowner, but it also means working with a professional forester to have the "right" trees cut. All timber cuts are not created equal. Depending on what your objectives are, what trees are harvested, and how they are harvested may be very different. If you are interested in creating good habitat for grouse, woodcock, or other early successional wildlife species, it is important that you work with a professional forester. You can also contact your regional DEC office to talk to a state forester. They will help you develop a management plan for your property that will include sustainable management of your forest stand that will follow strict "Best Management Practices" (BMPs). Sustainable forestry that follows BMPs is the best way to produce benefits for you and the wildlife on your land now and in the future.

More information about managing your forest for wildlife can be found through Cornell University's Master Forest Owner/COVERTS Program. Since 1991, the MFO/COVERTS Program has made on-site visits to over 1,000 New York forest owners to furnish technical guidance and assist with management plans. This program provides the information and encouragement necessary to help you manage your forest holdings wisely.

Landowner Resources