Why The Passenger Pigeon Disappeared And The
Mourning Dove Will Continue To Thrive
Deforestation for agriculture and many other human disturbances that were negative impacts for passenger pigeons create very favorable conditions for mourning doves.
Passenger Pigeon Compared to the Mourning Dove
Passenger Pigeon Compared to the Mourning Dove
Ectopistes migratorius is the scientific name for the passenger pigeon. For the mourning dove it is Zenaida macroura. The common city or farm pigeon is officially the rock pigeon (Columba livia). The Eurasian Collared-Dove is (Streptopelia decaocto). The ringed turtle dove is (Streptopelia risoria).
The two part Latin name tips you off to how closely related different species are. The first part refers to the genus. Although MODO and PAPI are in the same order (Columbiforme) and in the same family (Columidae) they are in different genus’. The PAPI is by itself in the Ectopistes genus; while the MODO is in the Zenaida genus with seven other species: white-winged dove, (Z. asiatica); West Peruvian dove, (Z. meloda); zenaida dove, (Z. aurita); galápagos dove, (Z. galapagoensis); eared dove, (Z. auriculata); socorro dove, (Z. graysoni). See the cladogram at the following link:
http://nydovehunting.weebly.com/cladogram-for-columbiformes.html
So what? says the NRA member, what does that have to do with the price of beans? Easy there nimrod, the significance is different animals have, well, differences…. And comparing MODO to PAPI is like apples to oranges. An orange tree typically cannot grow where an apple tree can, has different diseases, pests, parasites, requires different soil, daylight, temperature, precipitation, etc.. It produces a different number of fruit and at a different rate.
The two part Latin name tips you off to how closely related different species are. The first part refers to the genus. Although MODO and PAPI are in the same order (Columbiforme) and in the same family (Columidae) they are in different genus’. The PAPI is by itself in the Ectopistes genus; while the MODO is in the Zenaida genus with seven other species: white-winged dove, (Z. asiatica); West Peruvian dove, (Z. meloda); zenaida dove, (Z. aurita); galápagos dove, (Z. galapagoensis); eared dove, (Z. auriculata); socorro dove, (Z. graysoni). See the cladogram at the following link:
http://nydovehunting.weebly.com/cladogram-for-columbiformes.html
So what? says the NRA member, what does that have to do with the price of beans? Easy there nimrod, the significance is different animals have, well, differences…. And comparing MODO to PAPI is like apples to oranges. An orange tree typically cannot grow where an apple tree can, has different diseases, pests, parasites, requires different soil, daylight, temperature, precipitation, etc.. It produces a different number of fruit and at a different rate.
Regulated Hunting versus Market Hunting
And, something else is much different. Regulated hunting is much different than the market hunting which the PAPI was subjected to. Regulated hunting is underwritten and overseen by the United States Fish and Wildlife Service. The FWS hands down guidelines to the states. The guidelines are two kinds: Basic Regulations and Annual Regulations.
Basic regulations prohibit the use of nets, traps, or guns larger than 10 gauge and/or that holds more than 3 rounds or fires a single projectile. Bait cannot be used. Hunting is restricted to the daytime and night hunting is not allowed.
By contrast market hunting was done day and night; with bait, nets, fumigants, traps, 2, 4, 6, gauge punt guns that were more like pellet loaded cannons than shotguns with one shot killing a thousand or more birds. It is quite ridiculous to compare these market hunting tools with either the sporting arms of that era or of today, see images.
And, something else is much different. Regulated hunting is much different than the market hunting which the PAPI was subjected to. Regulated hunting is underwritten and overseen by the United States Fish and Wildlife Service. The FWS hands down guidelines to the states. The guidelines are two kinds: Basic Regulations and Annual Regulations.
Basic regulations prohibit the use of nets, traps, or guns larger than 10 gauge and/or that holds more than 3 rounds or fires a single projectile. Bait cannot be used. Hunting is restricted to the daytime and night hunting is not allowed.
By contrast market hunting was done day and night; with bait, nets, fumigants, traps, 2, 4, 6, gauge punt guns that were more like pellet loaded cannons than shotguns with one shot killing a thousand or more birds. It is quite ridiculous to compare these market hunting tools with either the sporting arms of that era or of today, see images.
Perhaps the most overlooked difference was the market for PAPI eggs and squab. Squab are nesting pigeons too young to fly. Market hunters would raid nests at night when the birds would not fly and take adults, eggs, and squabs.
Market hunters became more efficient by burning sulfur under roosts which caused adults and squabs to fall onto the ground. How anyone can suggest or believe, those practices are comparable to modern regulated hunting, or even the sustenance and sport hunting of that era, is mind boggling; (except that using fire and smoke for hunting was indeed a common practice of Native Americans before the arrival of European white settlers).
And this was done 365 days a year, although market hunters stepped up their effort during the nesting season. Without the basic and annual regulations handed down to the states by the FWS for today’s regulated hunting. These frameworks restrict hunting to certain months of the year, set a maximum number of days a hunting season can be set, and a maximum number of doves that can be harvested. How you can hunt, when you can hunt, what equipment and methods you can use, and how many birds you may harvest are all regulated. There is even a ‘Possession Limit”. While market hunters literally filled train cars with birds, today a hunter can only take the daily limit and possess at his home, hunting camp or the similar no more than 3 times the daily limit.
And this was done 365 days a year, although market hunters stepped up their effort during the nesting season. Without the basic and annual regulations handed down to the states by the FWS for today’s regulated hunting. These frameworks restrict hunting to certain months of the year, set a maximum number of days a hunting season can be set, and a maximum number of doves that can be harvested. How you can hunt, when you can hunt, what equipment and methods you can use, and how many birds you may harvest are all regulated. There is even a ‘Possession Limit”. While market hunters literally filled train cars with birds, today a hunter can only take the daily limit and possess at his home, hunting camp or the similar no more than 3 times the daily limit.
And, it has been illegal to sell migratory game birds for around a century, and that was exactly what market hunting was – selling harvested or live captured wildlife.
Framework Regulations and Basic regulations are Federal Laws and they are more or less constant and rarely changed. Annual regulations are set by the state, but must conform with the federal framework. The Annual Regulations allow the states to evaluate their migratory game bird populations and update them based on current population status.
Framework Regulations are the foundation of annual regulations and consist of the outside dates for opening and closing seasons, season length, daily bag and possession limits, and shooting hours. The earliest and latest dates within which states may hold hunting seasons are set by the Migratory Bird treaty Act. Shooting hours limit the time of day when migratory birds may be harvested, and have rarely been changed except when hunting seasons have become very restrictive. Since 1918, one-half hour before sunrise to sunset has been the traditional shooting hours.
Basic Regulations: This is not a complete list; it only includes what would be relevant to the market hunting practices of the past: Illegal to sell migratory game birds. No use of traps, nets, fish hook, stupefying substance, punt gun, gun which holds more than 3 rounds; use of a sink box or boat which hides hunter under the water surface; live decoys; baiting. Illegal to possess live birds. Must retrieve birds – cannot shoot a bunch and then allow domestic hogs to forage on them as done in the 19th century.
Possession Limits are also part of the Federal Basic Regulations.
Possession Limit: no more than three times the daily bag limit may be possessed at home, camp, one's home; habitation; place of dwelling; or residence, automobile, preservation facility, carrier facility, processing facility, taxidermist, storage facility. Nor is it legal to leave untagged migratory game birds with another person. Obviously market hunting would not have been profitable with today’s passion limits and during that era there was no restriction on number of birds possessed nor on the daily harvest..
Annual Regulations Set by state, may be more restrictive than Framework Regulations, but not less restrictive. For example Federal Frameworks may allow a state to set a daily bag limit of 15 mourning doves, however the state could instead limit daily harvest to 7 doves, however the state could not set the limit at more than 15. Same applies to length of hunting season.
The PAPI was much more abundant than MODO (4 billion compared to 500 million) but far less distributed than the MODO. The breeding range of the PAPI was especially miniscule compared to MODO. The range of the passenger pigeon in its migrations was from central Ontario, Quebec, and Nova Scotia south to the uplands of Texas, Louisiana, Alabama, Georgia, and Florida. Only a few birds were ever reported as far west as the Dakotas. The main nesting area was in the region of the Great Lakes and east to New York. The main wintering sites stretched from Arkansas to North Carolina south to the uplands of the Gulf Coast states. The PAPI may not have much choice on where to settle into huge nesting colonies, since it is believed their primary forage was nuts. Not only did that restrict them to large expanses of forest with mast trees, but it is likely they selected the great lakes area because deep winter snow buried nuts so that they were available during the nesting season. During a year when snow was little or absent, there would be far less mast available in the spring because other wildlife would be feeding on it all winter. If such is the case, it represented another weak link in the passenger pigeon’s ability to survive. It also strongly suggests PAPI lowered biodiversity and may explain why whitetail deer and wild turkey and some other wildlife are more abundant today than when the Pilgrims landed.
Framework Regulations and Basic regulations are Federal Laws and they are more or less constant and rarely changed. Annual regulations are set by the state, but must conform with the federal framework. The Annual Regulations allow the states to evaluate their migratory game bird populations and update them based on current population status.
Framework Regulations are the foundation of annual regulations and consist of the outside dates for opening and closing seasons, season length, daily bag and possession limits, and shooting hours. The earliest and latest dates within which states may hold hunting seasons are set by the Migratory Bird treaty Act. Shooting hours limit the time of day when migratory birds may be harvested, and have rarely been changed except when hunting seasons have become very restrictive. Since 1918, one-half hour before sunrise to sunset has been the traditional shooting hours.
Basic Regulations: This is not a complete list; it only includes what would be relevant to the market hunting practices of the past: Illegal to sell migratory game birds. No use of traps, nets, fish hook, stupefying substance, punt gun, gun which holds more than 3 rounds; use of a sink box or boat which hides hunter under the water surface; live decoys; baiting. Illegal to possess live birds. Must retrieve birds – cannot shoot a bunch and then allow domestic hogs to forage on them as done in the 19th century.
Possession Limits are also part of the Federal Basic Regulations.
Possession Limit: no more than three times the daily bag limit may be possessed at home, camp, one's home; habitation; place of dwelling; or residence, automobile, preservation facility, carrier facility, processing facility, taxidermist, storage facility. Nor is it legal to leave untagged migratory game birds with another person. Obviously market hunting would not have been profitable with today’s passion limits and during that era there was no restriction on number of birds possessed nor on the daily harvest..
Annual Regulations Set by state, may be more restrictive than Framework Regulations, but not less restrictive. For example Federal Frameworks may allow a state to set a daily bag limit of 15 mourning doves, however the state could instead limit daily harvest to 7 doves, however the state could not set the limit at more than 15. Same applies to length of hunting season.
The PAPI was much more abundant than MODO (4 billion compared to 500 million) but far less distributed than the MODO. The breeding range of the PAPI was especially miniscule compared to MODO. The range of the passenger pigeon in its migrations was from central Ontario, Quebec, and Nova Scotia south to the uplands of Texas, Louisiana, Alabama, Georgia, and Florida. Only a few birds were ever reported as far west as the Dakotas. The main nesting area was in the region of the Great Lakes and east to New York. The main wintering sites stretched from Arkansas to North Carolina south to the uplands of the Gulf Coast states. The PAPI may not have much choice on where to settle into huge nesting colonies, since it is believed their primary forage was nuts. Not only did that restrict them to large expanses of forest with mast trees, but it is likely they selected the great lakes area because deep winter snow buried nuts so that they were available during the nesting season. During a year when snow was little or absent, there would be far less mast available in the spring because other wildlife would be feeding on it all winter. If such is the case, it represented another weak link in the passenger pigeon’s ability to survive. It also strongly suggests PAPI lowered biodiversity and may explain why whitetail deer and wild turkey and some other wildlife are more abundant today than when the Pilgrims landed.
Passenger Pigeon
Ectopistes migratorius | Order COLUMBIFORMES – Family COLUMBIDAE
Figure 1. Distribution of the Passenger Pigeon.
Red color indicates area of regular distribution. Black indicates principal breeding area. Solid teal colored circles represent locations of casual or accidental occurrences.
Ectopistes migratorius | Order COLUMBIFORMES – Family COLUMBIDAE
Figure 1. Distribution of the Passenger Pigeon.
Red color indicates area of regular distribution. Black indicates principal breeding area. Solid teal colored circles represent locations of casual or accidental occurrences.
Mourning Dove
Figure 2. Distribution of the Mourning Dove.
Figure 2. Distribution of the Mourning Dove.
Mourning doves were also introduced to the Hawaiian Islands in the 1960s and a self-sustaining population still exists there.
The habitat of the passenger pigeon differed from MODO, and was mixed hardwood forests. The birds depended on the huge forests for their spring nesting sites, for winter roosts and for food.
Diet was different. The mainstays of the passenger pigeon's diet were beechnuts, acorns, chestnuts, seeds, and berries found in the forests. But the PAPI is thought by some to have been dependent on hard mast. Mast is a stochastic resource, and reliance on an ephemeral resource is a risky survival strategy.
Diet was different. The mainstays of the passenger pigeon's diet were beechnuts, acorns, chestnuts, seeds, and berries found in the forests. But the PAPI is thought by some to have been dependent on hard mast. Mast is a stochastic resource, and reliance on an ephemeral resource is a risky survival strategy.
And behavior was also different; one example was nesting in colonies. Another is winter roosts. In the winter the birds established roosting sites in the forests of the southern states. Each roost often had tremendous numbers of birds. PAPI also nested in colonies, something MODO definitely do not. A single site was typically miles long and miles wide; and the birds were so congested in these areas that hundreds of nests could be counted in a single tree. A large nesting in Wisconsin was reported as covering 850 square miles, and the number of birds nesting there was estimated at 136,000,000.
Because the passenger pigeon congregated in such huge numbers, and its preferred forage was nuts; it needed large forests, with a specific composition of tree species and age classes, (sexually mature oak, beech, chestnut, hickory) for its existence. When the early settlers cleared the eastern forests for farmland, the birds were forced to shift their nesting and roosting sites to the forests that still remained. And don’t forget about the chestnut tree blight which reduced or eliminated one mast bearing tree species, and a source of nuts, unless (if and when) other mast trees replaced the chestnuts. As their forest food supply decreased, some reports say the birds began utilizing the grain fields of the farmers. According to some sources, the large flocks of passenger pigeons often caused serious damage to the crops, and the farmers retaliated by shooting the birds and using them as a source of meat. However, this did not seem to seriously diminish the total number of birds. Nor did substance hunting and sport hunting. Yet most artist renditions show a couple of guys with an antique shotgun (even flintlock muskets in some). Why don’t they depict the sulfur fueled fires set under nest colonies, the most common and deadliest method used by market hunters? Because the goal is not to be factual, the goal is to convince people guys with shotguns can (and did) knocked the PAPI off the earth, which is complete rubbish. Didn’t happen, could not have happened.
The initial notable decrease of passenger pigeons started when professional hunters began netting and shooting the birds to sell in the city markets. The netting was an additional tool used by the market hunters, and it was efficient. Not only was netting efficient, birds could be sold live for a higher price or to new markets such as target shooter (target shooting is not hunting).
Because the passenger pigeon congregated in such huge numbers, and its preferred forage was nuts; it needed large forests, with a specific composition of tree species and age classes, (sexually mature oak, beech, chestnut, hickory) for its existence. When the early settlers cleared the eastern forests for farmland, the birds were forced to shift their nesting and roosting sites to the forests that still remained. And don’t forget about the chestnut tree blight which reduced or eliminated one mast bearing tree species, and a source of nuts, unless (if and when) other mast trees replaced the chestnuts. As their forest food supply decreased, some reports say the birds began utilizing the grain fields of the farmers. According to some sources, the large flocks of passenger pigeons often caused serious damage to the crops, and the farmers retaliated by shooting the birds and using them as a source of meat. However, this did not seem to seriously diminish the total number of birds. Nor did substance hunting and sport hunting. Yet most artist renditions show a couple of guys with an antique shotgun (even flintlock muskets in some). Why don’t they depict the sulfur fueled fires set under nest colonies, the most common and deadliest method used by market hunters? Because the goal is not to be factual, the goal is to convince people guys with shotguns can (and did) knocked the PAPI off the earth, which is complete rubbish. Didn’t happen, could not have happened.
The initial notable decrease of passenger pigeons started when professional hunters began netting and shooting the birds to sell in the city markets. The netting was an additional tool used by the market hunters, and it was efficient. Not only was netting efficient, birds could be sold live for a higher price or to new markets such as target shooter (target shooting is not hunting).
Perhaps restaurant markets preferred live birds as well so they could be fed and kept alive until needed or freshly slaughtered. Otherwise, cleaned birds were shipped in barrels with ice, as this was before modern refrigeration. Although the birds always had been used as food to some extent, including by the Indians, the real slaughter began in the 1800s.
There were no laws restricting the number of pigeons killed or the way they were taken. Because the birds were communal in habit, (Elongated nesting colonies several miles wide could reach a length of forty miles). In these colonies, droppings were thick enough to kill the forest understory. PAPI likely were a dominant, keystone species that lowered biodiversity. One example of this, which is a good illustration, but not one we are convinced is true; is some sources speculate that the PAPI kept lymes disease under control because they out-competed known lymes vectors (white footed mice). That may be plausible, but we are not convinced, for one reason, PAPI may or may not have been a vector for Lyme bacteria itself; however birds indeed carry ticks, and since they all fly and some migrate, including PAPI, birds potentially move more ticks around than mice or deer. It’s a good hypotheses, and a good illustration of the impact of a keystone species, but an unproven leap of biological faith. Never the less, the PAPI undoubtedly was a dominant keystone species that undoubtedly altered the landscape and biodiversity.
PAPI were easily netted by using baited traps and decoys. The birds were shot at the nesting sites, young squabs were knocked out of nests with long sticks, and pots of burning sulphur were placed under the roosting trees so the fumes would daze the birds and they would fall to the ground. Alcohol-soaked grain which made them drunk and easy to catch was another method used by market hunters. It was also a common agriculture practice of the day to feed PAPI to hogs.
What is seldom discussed is that more PAPI were taken than could be eaten or sold in the market. No it wasn’t sport trophy hunting target practice; these birds were fed to hogs and possibly to chickens. (Even John James Audubon admits this, as he wrote in his classic Birds of America, "The pigeons were picked up and piled in heaps, until each [hunter] had as many as he could possibly dispose of, when the hogs were let loose to feed on the remainder.")
PAPI were easily netted by using baited traps and decoys. The birds were shot at the nesting sites, young squabs were knocked out of nests with long sticks, and pots of burning sulphur were placed under the roosting trees so the fumes would daze the birds and they would fall to the ground. Alcohol-soaked grain which made them drunk and easy to catch was another method used by market hunters. It was also a common agriculture practice of the day to feed PAPI to hogs.
What is seldom discussed is that more PAPI were taken than could be eaten or sold in the market. No it wasn’t sport trophy hunting target practice; these birds were fed to hogs and possibly to chickens. (Even John James Audubon admits this, as he wrote in his classic Birds of America, "The pigeons were picked up and piled in heaps, until each [hunter] had as many as he could possibly dispose of, when the hogs were let loose to feed on the remainder.")
Here is what the Audubon Society says about the market hunting of PAPI:
The flocks were so thick that hunting was easy—even waving a pole at the low-flying birds would kill some. Still, harvesting for subsistence didn’t threaten the species’ survival. But after the Civil War came two technological developments that set in motion the pigeon’s extinction: the national expansions of the telegraph and the railroad. They enabled a commercial pigeon industry to blossom, fueled by professional sportsmen who could learn quickly about new nestings and follow the flocks around the continent. “Hardly a train arrives that does not bring hunters or trappers,” reported Wisconsin’s Kilbourn City Mirror in 1871. “Hotels are full, coopers are busy making barrels, and men, women, and children are active in packing the birds or filling the barrels. They are shipped to all places on the railroad, and to Milwaukee, Chicago, St. Louis, Cincinnati, Philadelphia, New York, and Boston.”
The professionals and amateurs together outflocked their quarry with brute force. They shot the pigeons and trapped them with nets, torched their roosts, and asphyxiated them with burning sulfur. They attacked the birds with rakes, pitchforks, and potatoes. They poisoned them with whiskey-soaked corn. Learning of some of these methods, Potawatomi leader Pokagon despaired. “These outlaws to all moral sense would touch a lighted match to the bark of the tree at the base, when with a flash—more like an explosion—the blast would reach every limb of the tree,” he wrote of an 1880 massacre, describing how the scorched adults would flee and the squabs would “burst open upon hitting the ground.” Witnessing this, Pokagon wondered what type of divine punishment might be “awaiting our white neighbors who have so wantonly butchered and driven from our forests these wild pigeons, the most beautiful flowers of the animal creation of North America.”
Ultimately, the pigeons’ survival strategy—flying in huge predator-proof flocks—proved their undoing. “If you’re unfortunate enough to be a species that concentrates in time and space, you make yourself very, very vulnerable,” says Stanley Temple, a professor emeritus of conservation at the University of Wisconsin.
Passenger pigeons might have even survived the commercial slaughter if hunters weren’t also disrupting their nesting grounds—killing some adults, driving away others, and harvesting the squabs. “It was the double whammy,” says Temple. “It was the demographic nightmare of overkill and impaired reproduction. If you’re killing a species far faster than they can reproduce, the end is a mathematical certainty.” The last known hunting victim was “Buttons,” a female, which was shot in Pike County, Ohio, in 1900 and mounted by the sheriff ’s wife (who used two buttons in lieu of glass eyes). Almost seven decades later a man named Press Clay Southworth took responsibility for shooting Buttons, not knowing her species, when he was a boy.
Even as the pigeons’ numbers crashed, “there was virtually no effort to save them,” says Joel Greenberg, a research associate with Chicago’s Peggy Notebaert Nature Museum and the Field Museum. “People just slaughtered them more intensely. They killed them until the very end.”
Market hunters devised a wide variety of techniques for slaughtering the pigeons and collecting their succulent squabs. Adults were baited with alcohol-soaked grain (which made them drunk and easy to catch), and suffocated by fires of grass or sulfur that were lit below their nests. To attract their brethren, captive pigeons, their eyes sewn shut, were set up as decoys on small perches called stools (which is the origin of the term stool pigeon for one who betrays colleagues). None of these methods of the market hunters are neither legal nor practiced in modern regulated hunting.
The flocks were so thick that hunting was easy—even waving a pole at the low-flying birds would kill some. Still, harvesting for subsistence didn’t threaten the species’ survival. But after the Civil War came two technological developments that set in motion the pigeon’s extinction: the national expansions of the telegraph and the railroad. They enabled a commercial pigeon industry to blossom, fueled by professional sportsmen who could learn quickly about new nestings and follow the flocks around the continent. “Hardly a train arrives that does not bring hunters or trappers,” reported Wisconsin’s Kilbourn City Mirror in 1871. “Hotels are full, coopers are busy making barrels, and men, women, and children are active in packing the birds or filling the barrels. They are shipped to all places on the railroad, and to Milwaukee, Chicago, St. Louis, Cincinnati, Philadelphia, New York, and Boston.”
The professionals and amateurs together outflocked their quarry with brute force. They shot the pigeons and trapped them with nets, torched their roosts, and asphyxiated them with burning sulfur. They attacked the birds with rakes, pitchforks, and potatoes. They poisoned them with whiskey-soaked corn. Learning of some of these methods, Potawatomi leader Pokagon despaired. “These outlaws to all moral sense would touch a lighted match to the bark of the tree at the base, when with a flash—more like an explosion—the blast would reach every limb of the tree,” he wrote of an 1880 massacre, describing how the scorched adults would flee and the squabs would “burst open upon hitting the ground.” Witnessing this, Pokagon wondered what type of divine punishment might be “awaiting our white neighbors who have so wantonly butchered and driven from our forests these wild pigeons, the most beautiful flowers of the animal creation of North America.”
Ultimately, the pigeons’ survival strategy—flying in huge predator-proof flocks—proved their undoing. “If you’re unfortunate enough to be a species that concentrates in time and space, you make yourself very, very vulnerable,” says Stanley Temple, a professor emeritus of conservation at the University of Wisconsin.
Passenger pigeons might have even survived the commercial slaughter if hunters weren’t also disrupting their nesting grounds—killing some adults, driving away others, and harvesting the squabs. “It was the double whammy,” says Temple. “It was the demographic nightmare of overkill and impaired reproduction. If you’re killing a species far faster than they can reproduce, the end is a mathematical certainty.” The last known hunting victim was “Buttons,” a female, which was shot in Pike County, Ohio, in 1900 and mounted by the sheriff ’s wife (who used two buttons in lieu of glass eyes). Almost seven decades later a man named Press Clay Southworth took responsibility for shooting Buttons, not knowing her species, when he was a boy.
Even as the pigeons’ numbers crashed, “there was virtually no effort to save them,” says Joel Greenberg, a research associate with Chicago’s Peggy Notebaert Nature Museum and the Field Museum. “People just slaughtered them more intensely. They killed them until the very end.”
Market hunters devised a wide variety of techniques for slaughtering the pigeons and collecting their succulent squabs. Adults were baited with alcohol-soaked grain (which made them drunk and easy to catch), and suffocated by fires of grass or sulfur that were lit below their nests. To attract their brethren, captive pigeons, their eyes sewn shut, were set up as decoys on small perches called stools (which is the origin of the term stool pigeon for one who betrays colleagues). None of these methods of the market hunters are neither legal nor practiced in modern regulated hunting.
Squabs were knocked from nests with long poles, trees were chopped down or were set on fire to make the squabs jump from nests.
We all heard the saying “as cheap as chicken feed” or reference to a small amount of money as “chicken feed”. So successful were the market hunters that pigeons became cheap hog and chicken feed and some were captured alive for use as live targets in shooting galleries. Target practice and hunting are not the same thing, by the way and this 19th century practice has nothing to do with hunting.
Disruption of the colonies was so severe that wholesale nest abandonment was common and breeding success was severely reduced.
Some animals live in colonies and depend on extremely large populations for survival. With those species, when their population is reduced to a “tipping point”, recovery is difficult. The PAPI was one of those animals that lived in colonies and was obligated to an exceedingly large population size for survival.
The passenger pigeon's technique of survival had been based on mass tactics. There had been safety in its large flocks which often numbered hundreds of thousands of birds. When a flock of this size established itself in an area, the number predators, including Native Americans, was so small compared to the total number of birds that little damage could be inflicted on the flock as a whole. That survival strategy worked well against most predators, but was counterproductive when white settlers entered the picture.
When the birds were massed together, especially at a nesting site, it was easy for man to slaughter them in such huge numbers that there were not enough birds left to successfully reproduce the species.
The interests of civilization, with its forest clearing and farming, were diametrically opposed to the interests of the birds which needed the huge forests to survive. The passenger pigeons could not adapt themselves to existing in small flocks. When their interests clashed with the interests of man, civilization prevailed. Mourning doves, however, thrive in the conditions created by human civilization, a few examples of many are; field crops, grain crops, and livestock whether it is free range pasture, dairy, or feed lots. Additionally, many non-agricultural practices also favor mourning dove populations.
As a matter of fact, our modern lifestyle could not continue as we know it without coincidentally sustaining favorable conditions for mourning doves…. Almost everything we do facilitates mourning doves, and we cause little negative impact to them. And that includes hunting mortality, which is on average around 20 million birds each year. As a matter of fact, mourning dove populations increased since regulated hunting initiated in 1918, with the steepest increases occurring in the last 50 years. Furthermore, during those 50 years, the number of states that allow mourning dove hunting almost doubled. Clearly, mourning dove populations are not only sustained, but have grown, despite being subjected to regulated hunting since 1918.
According to the Department of Vertebrate Zoology, National Museum of Natural History Smithsonian Institution; “The wanton slaughter of the birds only sped up the process of extinction. The converting of forests to farmland would have eventually doomed the passenger pigeon”.
Disruption of the colonies was so severe that wholesale nest abandonment was common and breeding success was severely reduced.
Some animals live in colonies and depend on extremely large populations for survival. With those species, when their population is reduced to a “tipping point”, recovery is difficult. The PAPI was one of those animals that lived in colonies and was obligated to an exceedingly large population size for survival.
The passenger pigeon's technique of survival had been based on mass tactics. There had been safety in its large flocks which often numbered hundreds of thousands of birds. When a flock of this size established itself in an area, the number predators, including Native Americans, was so small compared to the total number of birds that little damage could be inflicted on the flock as a whole. That survival strategy worked well against most predators, but was counterproductive when white settlers entered the picture.
When the birds were massed together, especially at a nesting site, it was easy for man to slaughter them in such huge numbers that there were not enough birds left to successfully reproduce the species.
The interests of civilization, with its forest clearing and farming, were diametrically opposed to the interests of the birds which needed the huge forests to survive. The passenger pigeons could not adapt themselves to existing in small flocks. When their interests clashed with the interests of man, civilization prevailed. Mourning doves, however, thrive in the conditions created by human civilization, a few examples of many are; field crops, grain crops, and livestock whether it is free range pasture, dairy, or feed lots. Additionally, many non-agricultural practices also favor mourning dove populations.
As a matter of fact, our modern lifestyle could not continue as we know it without coincidentally sustaining favorable conditions for mourning doves…. Almost everything we do facilitates mourning doves, and we cause little negative impact to them. And that includes hunting mortality, which is on average around 20 million birds each year. As a matter of fact, mourning dove populations increased since regulated hunting initiated in 1918, with the steepest increases occurring in the last 50 years. Furthermore, during those 50 years, the number of states that allow mourning dove hunting almost doubled. Clearly, mourning dove populations are not only sustained, but have grown, despite being subjected to regulated hunting since 1918.
According to the Department of Vertebrate Zoology, National Museum of Natural History Smithsonian Institution; “The wanton slaughter of the birds only sped up the process of extinction. The converting of forests to farmland would have eventually doomed the passenger pigeon”.
- Deforestation for agriculture and many other human disturbances that were negative impacts for passenger pigeons create very favorable conditions for mourning doves.
Furthermore, the most recent research is revealing possibilities that were not previously considered. There were many factors in the demise of the PAPI. “They were not always super-abundant and boom-and-bust cycles might have been written into the passenger pigeon's DNA and contributed to the species’ downfall”. "The passenger pigeon was likely to experience dramatic population fluctuations."; according to molecular ecologist Hung Chih-Ming, who began studying the birds at the University of Minnesota in the lab of avian evolutionary biologist Robert Zink; and is now a postdoctoral associate at National Taiwan Normal University and lead author of an analysis on this topic that was published in Proceedings of the National Academy of Sciences.
Hung’s research developed a genetic map and with this map of genetic variation in hand, the scientists could then estimate how big the population of passenger pigeons once was—typically, a small population will have less genetic variation than a larger one because it derives from a smaller pool of ancestors who bred successfully. Through this technique of looking at many genes on a single genome for variations, a smattering of birds from across the breeding range can reveal the approximate number of their peers.
In the case of the passenger pigeon, Hung and his colleagues concluded that the population of breeding birds was roughly 330,000 on average, falling to as few as 50,000 birds at points in the last million years. This mismatch between these numbers and 1880 estimates of at least three billion suggests that the passenger pigeon may have been what is known to ecologists as an "outbreak" species, like locusts, that boom and bust with changes in conditions, rather than a species that experiences a singular population explosion, as people have in the last 200 years.
This answer from genetics matches up well with ecological modeling of the abundance of passenger pigeon food—acorns, beechnuts and other forest mast—in North America over the last few thousand years. Such computer simulations suggest a population crash for passenger pigeons some 21,000 years ago as glaciers buried the trees that gave them food, followed by a rebound around 6,000 years ago to as many as 1.6 billion birds.
This boom-and-bust scenario also lines up well with arguments by some that human immigration from Europe may have artificially swelled the ranks of the passenger pigeon by eliminating their Native American hunters and foragers, who competed with the birds for nuts and other forest foods. This population growth, the story goes, would have been temporary, because large flocks would have damaged the forests that provided food to the pigeons. "I suspected that the huge flocks of passenger pigeons that were observed when Europeans first arrived in North America were something ephemeral," notes paleogenomicist Beth Shapiro of the University of California, Santa Cruz, who was not involved in (Hung’s) work but is also working on sequencing the passenger pigeon genome. "It is hard to imagine how these birds could sustain such enormous populations over the long term. They were so incredibly destructive to the forests!"
After all, the massive flocks were like a biological storm, cracking trees under the weight of birds and covering the ground in excrement, among other impacts. European settlers exacerbated this arboreal destruction, clearing the great U.S. eastern forest over the course of the 19th century. This downward trend in the abundance of forest mast (acorns, etc.) paired with increased hunting by these same humans may then have combined to trigger the passenger pigeon's rapid extinction. "I think the reduction of habitat definitely decreased their population size," Hung says, noting something similar may explain the extinction of other outbreak species in North America, like the Rocky Mountain grasshopper in the western U.S. "Our study suggests that the combination of natural population size changes and human disturbances drove the rapid extinction of this bird."
Effective Colony Size?
Many ecological systems have critical thresholds where, when a tipping point is passed, the system shifts to another state. In this new state the system either collapses or cannot be sustained. Prior to the 18th century, the passenger pigeon was the probably the most common bird in North America, at least for certain time periods. At first no signals of extinction resulted from the falling amount of passenger pigeons. Yet, at one point a minimum population for reproduction was reached, as those pigeons were more successful in big than in small flocks. This critical tipping point produced a situation that had to lead to the extinction of the bird. When the population declined to a certain size, the system switched from state normal to state catastrophic. At one point, the critical amount of pigeons was reached and the system changed.
When populations decline or “crash”, the survivors constitute a genetic “bottleneck” often leading to a gene pool is less diverse than that which existed in the original population. Genes that enable survival become rare or completely lost, and a low diversity of genes means the species is less able to survive or adapt to new diseases or other threats.
Then there is the Information Center Hypothesis. The Information Center Hypothesis suggest that colonially breeding birds learn the location of good feeding sites by following successful birds from a colony, that such information exchange was critical to the evolution of coloniality, and that colonies acting as Information Centers are important for birds in all colonial species.
Colonial birds, especially those with large populations, need to locate new feeding sites often because old sites become depleted or unavailable. These birds can discover feeding sites through independent hunting or through four types of socially facilitated searching.
The first socially facilitated type involves birds at a colony or other areas cueing to feeding flocks.
Second, birds at foraging areas, roosts, or a colony can cue to the direction in which birds are flying either en masse.
Third, birds can cue to the direction from which other birds are returning to the colony.
Fourth, birds can follow other birds from roosts or a colony to the previous feeding site of the leader(s). This is the Information Center hypothesis.
Some researchers believe the PAPI traveled nomadically in search of synchronized reproducing mast trees (chestnut, oak, hickory and beech). This seems to make sense. If these extreme populations needed miles and miles of mast production for food, yet depleted them quickly, then Information Centers may have been important. And, the mast in the northeast may have not been able to support the number of birds, and therefore extinction was a matter of time if the birds could not adapt to a new food source or foraging strategy, which very well may have been the case. Perhaps almost every PAPI on the continent formed one large flock which followed the production of mast. If so, extinction is of no surprise.
Mourning Doves are Different and Regulated Hunting is Different
Regulated Hunting
The US Fish and Wildlife Service sets the framework for migratory game bird hunting regulations based on recent population estimates, a posteriori knowledge, and other factors. State Wildlife Agencies (the DEC) are required to conform to this framework in setting hunting regulations for migratory game birds.
Mourning dove populations are carefully monitored by the United States Fish and Wildlife Service. During this monitoring, which has existed for many years alongside dove hunting; the mourning dove populations have remained abundant without dropping precipitously; which indicates the existing dove conservation strategy is sound. Nevertheless, the US Fish and Wildlife Service Migratory Shore and Upland Bird Support Task Force and the Association of Fish and Wildlife Agencies periodically review and update mourning dove conservation needs, seek new information, and adjust hunting regulations as needed.
Population data goes back to 1966 and hunting migratory game birds has been a tradition for centuries in this country and federally regulated migratory game bird hunting seasons have been ongoing since 1918.
At the time of this writing, the federal process of establishing migratory bird hunting regulations in the U.S. has existed for over 98 years. The Service characterizes the goal for migratory bird hunting regulations as: To establish regulations consistent with the long-term conservation of each species and recognized populations
A testament to the success of this endeavor is that migratory game bird populations have been maintained throughout this 98 year period (at the time of this writing 2016). Only three game birds have been listed as either threatened or endangered (Aleutian Canada goose, Steller’s and spectacled eiders), and in none of these instances was hunting believed to be the cause. In addition, one of the three (Aleutian Canada goose) recently has been delisted, having increased from as few as 800 individuals to approximately 112,000, a level at which some harvest is again being permitted. Many species of ducks were at or near their highest population levels (for the 1955-2011 time period, the period when operational WBPHS surveys have been conducted) as recently as 1995. These high population numbers support the validity of the general regulatory approach practiced by the Service over the past century and supports the fact that properly managed harvest is consistent with long-term conservation
The passenger pigeon was what is known as an "overly adapted" species, or, sometimes, a "degenerated species". By the time of the arrival of European settlers, the bird would only breed and reproduce when in the presence of large numbers of its own kind. Further, by this time, the bird would only lay one or two eggs per year, whereas in former times it would have had to have had a much more robust birth rate in order to reach numbers of several billion. Efforts to get the birds to breed in captivity failed. Even when a female in captivity would lay an egg or two, she would not bother to incubate it. When numbers of the pigeon diminished, so that they were no more numerous than other birds, the passenger pigeon would not or could not replenish itself, even though other birds of similar numbers were doing so. Over hunting of the species, while regrettable and lamentable, was not, in the long run, responsible for its extinction. The passenger pigeon was unable or unwilling to adapt to changing conditions the way the mourning dove was able to do. The virtual extinction of the chestnut tree a few decades later (a major food source for the pigeon) would have also diminished the numbers of the pigeon, since the chestnut tree was, much more than the beech tree, a dominant tree species of the eastern forests.
Mourning Doves
Although the abundance of PAPI is often referred to, their distribution was not as large as the MODO.
Nor was the PAPI as adaptable as the mourning dove. The primary forage of the PAPI was mast, however trees take many years to produce mast, and the yield fluctuates year to year. The natural forage of MODO by contrast is the seeds of ANNAUL plants. Annual is important – it means seeds are produced every year and when the seeds are not available MODO migrates to were food is available. And mourning doves will also eat waste grain and pokeberries. Mourning doves will nest in trees or on the ground, and we are not aware of any references to PAPI nesting on the ground. So unlike the PAPI, the MODO was not tied to mature mast trees. As a matter of fact, mourning doves have increased due to man-made changes in the landscape such as farming, livestock grazing, dairy farms, suburban development, utility right of ways and rail roads, planting trees in the Midwest, and even new telephone lines.
And although MODO are one of the most abundant birds (11th in relative abundance) they do not nest in colonies. They typically migrate in small flocks and roosts seldom exceed 1,000 birds. 1,000 birds might be a lot, but not compared to several million. MODO does not depend on large congregations for survival; as a matter of fact males will stake out breeding territories and defend it from other males.
What if all of the open land reverted to old growth forest, virtually the only biome unfavorable to mourning doves; and wildlife such as whitetail deer, turkey, and many others virtually disappear, what would happen to the MODO? Probably very little. Every lawn in the USA has blue grass or fescue seeds. And people need to eat – so there will be farms and dairies. Would more doves be crammed into less space? Maybe yes or no, but either way it is unlikely they will be threatened with extinction. But let’s be realistic (for a change when discussing mourning doves), the MODO is here to stay and is far more adaptable than the common pigeon (rock pigeon) or the Norway rat. Or the native red-winged blackbird…. And, although it is similar in appearance to the PAPI, and in the same order and family, it is a much different bird and we are living in a different era. An era of regulated hunting; we are not living during the industrial revolution. We are not living in an era that would tolerate huge populations of PAPI; and we are living in an era which biodiversity, which PAPI lowered, is valued. When the huge flocked reigned, there were fewer other critters, both big and small. The PAPI also controlled the plant life too; both the composition of plant species, and the plant structure. And besides, as we discussed some sources make compelling arguments that the PAPI dominance was cyclic and equally compelling arguments were that the PAPI was doomed and its place on earth was not sustainable, with or without the influence of humans.
There is a lot more to the PAPI story than what is disseminated to the public. Much of what is sensationalized is pure non-sense. Statements or art work which implicitly or expressly suggest regular hunters with a shotgun, or even thousands of regular hunters; caused or even contributed to the extinction are not only incorrect, but irresponsible. Even some of the brilliant research done and models developed, by persons who never hunted and did not study hunting, arrived at somewhat erroneous conclusions due to such. It should be quite obvious, at least to a hunter, that the most plausible explanation for the extinction was the practice of the market hunters of disturbing the birds in nesting colonies, which eventually shut off reproduction. Animals do not stick around and say shoot me, they flee, and the more encounters with hunters they survive, the better they get at fleeing. But these birds were fleeing without reproducing. If you lose your job, and keep spending money, your bank account balance eventually is zero. Your money is extinct. By using scouts, telegrams, and trains to track flocks, notify market hunters, and transport them to the nest colonies; market hunters reached flocks soon after they began the business of reproducing. No surprise to any hunter, the PAPI modified their behavior in response to hunting pressure; but that meant forfeiting reproduction. In a modern hunting situation, relocating to a different resource area is an effective survival strategy, because modern regulated hunting does not occur during nesting season, thus it does not shut down reproduction.
Sure, the PAPI had a lot of things working against it, and as some suggested, market hunting only speeded up the extinction that was going to eventually happen anyway. And, if it did not, the society we live in today would not tolerate flocks of that size, much as the wolf cannot be recovered to its historical populations or even maintain its current restored numbers, because people do not tolerate them (and never will right or wrong). And, today, the importance of biodiversity is known and valued. No doubt PAPI reduced biodiversity if the historical accounts are even close to true. But if a single precipitating factor must be assigned to the PAPI demise, we would hedge our guess the relentless disturbance of breeding colonies shut down reproduction. Especially when the markets were able to communicate with thousands of market hunters by telegraph to tell them were the nomadic flocks settled to nest, and rail lines were expanded to these areas to get the market hunters out to the birds and the birds back to the markets. Loss of mast forests, chestnut blight, a tipping point below an effective population size and all of the other factors contributed, but reproduction is designed to offset such factors, however, if it is shut down , nature’s defense is gone.
Deforestation for agriculture and many other human disturbances that were negative impacts for passenger pigeons create very favorable conditions for mourning doves.
Regulated Hunting
The US Fish and Wildlife Service sets the framework for migratory game bird hunting regulations based on recent population estimates, a posteriori knowledge, and other factors. State Wildlife Agencies (the DEC) are required to conform to this framework in setting hunting regulations for migratory game birds.
Mourning dove populations are carefully monitored by the United States Fish and Wildlife Service. During this monitoring, which has existed for many years alongside dove hunting; the mourning dove populations have remained abundant without dropping precipitously; which indicates the existing dove conservation strategy is sound. Nevertheless, the US Fish and Wildlife Service Migratory Shore and Upland Bird Support Task Force and the Association of Fish and Wildlife Agencies periodically review and update mourning dove conservation needs, seek new information, and adjust hunting regulations as needed.
Population data goes back to 1966 and hunting migratory game birds has been a tradition for centuries in this country and federally regulated migratory game bird hunting seasons have been ongoing since 1918.
At the time of this writing, the federal process of establishing migratory bird hunting regulations in the U.S. has existed for over 98 years. The Service characterizes the goal for migratory bird hunting regulations as: To establish regulations consistent with the long-term conservation of each species and recognized populations
A testament to the success of this endeavor is that migratory game bird populations have been maintained throughout this 98 year period (at the time of this writing 2016). Only three game birds have been listed as either threatened or endangered (Aleutian Canada goose, Steller’s and spectacled eiders), and in none of these instances was hunting believed to be the cause. In addition, one of the three (Aleutian Canada goose) recently has been delisted, having increased from as few as 800 individuals to approximately 112,000, a level at which some harvest is again being permitted. Many species of ducks were at or near their highest population levels (for the 1955-2011 time period, the period when operational WBPHS surveys have been conducted) as recently as 1995. These high population numbers support the validity of the general regulatory approach practiced by the Service over the past century and supports the fact that properly managed harvest is consistent with long-term conservation
The passenger pigeon was what is known as an "overly adapted" species, or, sometimes, a "degenerated species". By the time of the arrival of European settlers, the bird would only breed and reproduce when in the presence of large numbers of its own kind. Further, by this time, the bird would only lay one or two eggs per year, whereas in former times it would have had to have had a much more robust birth rate in order to reach numbers of several billion. Efforts to get the birds to breed in captivity failed. Even when a female in captivity would lay an egg or two, she would not bother to incubate it. When numbers of the pigeon diminished, so that they were no more numerous than other birds, the passenger pigeon would not or could not replenish itself, even though other birds of similar numbers were doing so. Over hunting of the species, while regrettable and lamentable, was not, in the long run, responsible for its extinction. The passenger pigeon was unable or unwilling to adapt to changing conditions the way the mourning dove was able to do. The virtual extinction of the chestnut tree a few decades later (a major food source for the pigeon) would have also diminished the numbers of the pigeon, since the chestnut tree was, much more than the beech tree, a dominant tree species of the eastern forests.
Mourning Doves
Although the abundance of PAPI is often referred to, their distribution was not as large as the MODO.
Nor was the PAPI as adaptable as the mourning dove. The primary forage of the PAPI was mast, however trees take many years to produce mast, and the yield fluctuates year to year. The natural forage of MODO by contrast is the seeds of ANNAUL plants. Annual is important – it means seeds are produced every year and when the seeds are not available MODO migrates to were food is available. And mourning doves will also eat waste grain and pokeberries. Mourning doves will nest in trees or on the ground, and we are not aware of any references to PAPI nesting on the ground. So unlike the PAPI, the MODO was not tied to mature mast trees. As a matter of fact, mourning doves have increased due to man-made changes in the landscape such as farming, livestock grazing, dairy farms, suburban development, utility right of ways and rail roads, planting trees in the Midwest, and even new telephone lines.
And although MODO are one of the most abundant birds (11th in relative abundance) they do not nest in colonies. They typically migrate in small flocks and roosts seldom exceed 1,000 birds. 1,000 birds might be a lot, but not compared to several million. MODO does not depend on large congregations for survival; as a matter of fact males will stake out breeding territories and defend it from other males.
What if all of the open land reverted to old growth forest, virtually the only biome unfavorable to mourning doves; and wildlife such as whitetail deer, turkey, and many others virtually disappear, what would happen to the MODO? Probably very little. Every lawn in the USA has blue grass or fescue seeds. And people need to eat – so there will be farms and dairies. Would more doves be crammed into less space? Maybe yes or no, but either way it is unlikely they will be threatened with extinction. But let’s be realistic (for a change when discussing mourning doves), the MODO is here to stay and is far more adaptable than the common pigeon (rock pigeon) or the Norway rat. Or the native red-winged blackbird…. And, although it is similar in appearance to the PAPI, and in the same order and family, it is a much different bird and we are living in a different era. An era of regulated hunting; we are not living during the industrial revolution. We are not living in an era that would tolerate huge populations of PAPI; and we are living in an era which biodiversity, which PAPI lowered, is valued. When the huge flocked reigned, there were fewer other critters, both big and small. The PAPI also controlled the plant life too; both the composition of plant species, and the plant structure. And besides, as we discussed some sources make compelling arguments that the PAPI dominance was cyclic and equally compelling arguments were that the PAPI was doomed and its place on earth was not sustainable, with or without the influence of humans.
There is a lot more to the PAPI story than what is disseminated to the public. Much of what is sensationalized is pure non-sense. Statements or art work which implicitly or expressly suggest regular hunters with a shotgun, or even thousands of regular hunters; caused or even contributed to the extinction are not only incorrect, but irresponsible. Even some of the brilliant research done and models developed, by persons who never hunted and did not study hunting, arrived at somewhat erroneous conclusions due to such. It should be quite obvious, at least to a hunter, that the most plausible explanation for the extinction was the practice of the market hunters of disturbing the birds in nesting colonies, which eventually shut off reproduction. Animals do not stick around and say shoot me, they flee, and the more encounters with hunters they survive, the better they get at fleeing. But these birds were fleeing without reproducing. If you lose your job, and keep spending money, your bank account balance eventually is zero. Your money is extinct. By using scouts, telegrams, and trains to track flocks, notify market hunters, and transport them to the nest colonies; market hunters reached flocks soon after they began the business of reproducing. No surprise to any hunter, the PAPI modified their behavior in response to hunting pressure; but that meant forfeiting reproduction. In a modern hunting situation, relocating to a different resource area is an effective survival strategy, because modern regulated hunting does not occur during nesting season, thus it does not shut down reproduction.
Sure, the PAPI had a lot of things working against it, and as some suggested, market hunting only speeded up the extinction that was going to eventually happen anyway. And, if it did not, the society we live in today would not tolerate flocks of that size, much as the wolf cannot be recovered to its historical populations or even maintain its current restored numbers, because people do not tolerate them (and never will right or wrong). And, today, the importance of biodiversity is known and valued. No doubt PAPI reduced biodiversity if the historical accounts are even close to true. But if a single precipitating factor must be assigned to the PAPI demise, we would hedge our guess the relentless disturbance of breeding colonies shut down reproduction. Especially when the markets were able to communicate with thousands of market hunters by telegraph to tell them were the nomadic flocks settled to nest, and rail lines were expanded to these areas to get the market hunters out to the birds and the birds back to the markets. Loss of mast forests, chestnut blight, a tipping point below an effective population size and all of the other factors contributed, but reproduction is designed to offset such factors, however, if it is shut down , nature’s defense is gone.
Deforestation for agriculture and many other human disturbances that were negative impacts for passenger pigeons create very favorable conditions for mourning doves.
It is estimated that in the 1600's, the United States was 46 percent forested. Timber was quickly harvested for housing, industry, the creation of railroads and to clear land for farming. By 1907, the U.S. forest cover was reduced to 33 percent.