Trouble for the ruffed grouse in PA
Hunters in PA have always looked forward to going afield with a dog and pursuing the elusive ruffed grouse. You can hunt this species without a dog, but it is a lot more difficult, as these well camouflaged birds flush out of cover and provide the briefest of targets before they rapidly disappear in forest cover. Many people just get to hear the wing beats and see little or nothing of the grouse. In recent years, during walks through the forest, it seems there are fewer grouse flushing, and less drumming during the spring breeding season (a sound that males make to attract females and to ward off other males in its territory).
The PA Game Commission (PGC) has been doing some significant research and has come up with four indicators revealing that the ruffed grouse population is in distress: 1) depressed hunter flush rates (grouse flushes per hour); 2) declining July and August brood observations (an index of brood survival); 3) dramatically decreased recruitment of juveniles into the adult population since the 1980s (i.e. very low juvenile per hen ratios in hunter-harvested birds and summer brood sightings); and 4) decreased proportion of juveniles in the winter harvest (December and January).
According to PGC Biologist Lisa Williams, a major factor in the declining grouse population is declining favorable habitat; grouse thrive in young forest habitat where they forage mainly on buds and berries. As forests mature, there is less ground cover and smaller trees which grouse use for food and protection. In addition, West Nile Virus, which affects avian species, has caused some mortality of ruffed grouse populations in PA and elsewhere. This occurs during the warmer months when the main vector for this virus, a species of mosquito called Culex restuans, is present.
Because of the drastic population decline, including record-low brood observations in 2017 (the second lowest in 37 years of monitoring), the late season hunting season (after Christmas) closure that was in effect for the 2017/2018 season will be in effect again for the upcoming season. It is hoped that this will help carry more birds into the spring breeding season. In some game lands, forestry management is taking place to provide more favorable grouse habitat.
A webinar held on February 15 by Lisa Williams reviewed some of the factors involved in grouse management, including West Nile virus. About 55 minutes long, it can be found at bit.ly/2sXh1To.