Photo from google images of a ruffed grouse.
The ruffed grouse (Bonasa umbellus) prefers habitat that is quite the opposite of that favored by the bird I discussed last week. Whereas the ivory-billed woodpecker required deep virgin forests in lowland swamps, ruffed grouse need frequently disturbed early successional forests growing on the uplands of elevations over 1000 feet.
Ruffed grouse range. Lighter pink indicates low population density, darker pink indicates higher density. Most of the ruffed grouse’s present day range was under glacial ice during many Pleistocene climate phases.
The ruffed grouse is a rare bird in Georgia today, inhabiting only the northern mountain region. According to the state DNR rare stragglers have ventured as far south as Clark County, but I think this is not based on a recent sighting. This bird is declining in state due to fire suppression and the regrowth of clear cuts into mature timber. During the 2005/2006 season (the most recent year for statistics online), hunters only bagged 28 or .13 per hunt. They may be more common than this indicates, however, because they live at high altitudes. All but the most vigorous hunters avoid these strenous terrains. Nevertheless, they’re definitely not common in the state. I’ve never seen one.
I’m interested in this bird because their bones were the most common avian specimens excavated from Kingston Saltpeter Cave in Bartow County, Georgia which is just south of where they currently range today. Fossil evidence of ruffed grouse has also been excavated from Tunica Hills, Louisiana and Arredondo in Florida, proving this bird once ranged much farther south than it does today.
From fossils found in Kingston Saltpeter Cave scientists counted 191 ruffed grouse bones from at least 31 individuals. They also found 31 bones that probably belonged to ruffed grouse but from their condition couldn’t be definitively differentiated from spruce grouse. This makes the ruffed grouse by far the most common bird species found at the site with passenger pigeons coming in a distant second with 35 bones from at least 5 individuals. Ruffed grouse bones were also the most common among bird fossils excavated from Bell Cave in northern Alabama. This data suggests ruffed grouse were formerly the most common bird in the southern Appalachians during the Ice Age, though not necessarily. The presence of bird bones in cave deposits can usually be attributed to predators transporting them there. It may be they were the easiest for predators to kill, accounting for a higher frequency than their actual numbers. Also, ruffed grouse are a permanent resident, while passenger pigeons were migratory. Passenger pigeons likely outnumbered grouse during certain times of the year. Anyway, it’s evident ruffed grouse were a common bird in the upper south during cooler climate phases.
Today, ruffed grouse prefer shrubby dense woods with sunny thickets. They like woods with oaks for mast and evergreen trees for cover. They live in young stands of trees with some mature mast-producing trees left standing. The Georgia DNR has very specific recomendations for managing grouse habitat. For grouse habitat they recomend clear cutting or burning 5-20 acre plots, leaving clumps of oak saplings as well as shrubby hedgerows. Clover should be planted; grapes, dogwoods, and blueberries should be fertilized. Although the chicks eat insects, the adults are mostly vegetarian subsisting on acorns, fruit, flowers, buds, young leaves, mushrooms, and twigs.
The excavated fossils from KSP date to ~15,000 calender years BP (from a 12,470 year radiocarbon date on a deer bone), the beginning of a warm stage of the last Ice Age known as the Boling-Alerod. Habitat must have been frequently disturbed during this climatic stage. Paleo-Indians, if present this early in the region, were likely just passing through, and not populous enough to have much of an impact on the environment. It must have been natural forces that shaped grouse habitat 15,000 years ago. Frequent storms caused by glacial cold fronts mixing with warm gulf air sparked numerous tornadoes and lightning-ignited fires that wrecked whole stretches of forests. While traveling through north Georgia this summer I witnessed much tornado damage from this year’s uncommonly stormy season. A few mature trees would often remain standing in the otherwise devastated lots–similar to what the Georgia DNR recomends for grouse habitat. Clear cutting and controlled burning merely mimics these natural forces. The climatic conditions of the Boling-Alerod probably caused deeper snows in north Georgia than occur during present day winters. Grouse like to use deep snow as cover, and they’ll fly directly into snow banks. Deep snow helps grouse escape predators. The lack of deep snow in the south may be one reason they’re absent in the region today.
Mastodon and giant ground sloth foraging shaped favorable grouse habitat as well. Browsed trees sprout nutritious new growth, and the plants grow in a more shrubby pattern. The new growth provided food for grouse; the shrubby growth pattern added cover. Georgia’s DNR recomendation to fertilize fruit-bearing plants mimics former megafauna dung-depositing.
In remote areas grouse tend to be naive birds easily hunted. Early settlers referred to them as “fool hens” because young boys could walk up to the birds and kill them with stones. Dersu, the trapper, showed V.K Arseniev how to save bullets and catch an unwary species of grouse living in an unexplored part of Siberia 100 years ago. Since then, grouse have learned to be afraid of man, but the first Paleo-Indians traveling through the south must have utilized them as a plentiful food source.
Dersu the Trapper
E.P. Dutton 1941
Sneed, Joel; and Larry O. Blair
The Late Pleistocene Record of Kingston Saltpeter Cave, Bartow County, Georgia
The Kingston Saltpeter Cave Project 2005