By Mark Petrie, Ph.D.
Then some old man would shake his head and say, "Beats all, the geese came back." And no one spoke, for the old man had summarized the best thing that had happened to the Eastern Shore in a hundred years. —James Michener, Chesapeake.
It's been five decades since Maryland 's Eastern Shore was transformed from a waning duck destination into the world's first goose hunting capital. Since then, goose numbers have grown largely unchecked from Chesapeake Bay clear to Humboldt County, California. The resurgence of goose populations in North America may be the greatest success story in wildlife management, a claim only white-tailed deer and wild turkey biologists would dispute. If you hunt geese, times have never been better.
The story of North America 's geese can be read in the plain statistics of waterfowl management. Today, there are nearly three times as many geese as there were just 30 years ago. During the 1960s, U.S. hunters harvested an average of a million geese a year. By 2003, the goose harvest was approaching 4 million, which is about the number of mallards we shoot in a typical season. Thirty years ago hunters bagged the occasional goose while duck hunting. Today geese provide the bulk of the hunting opportunity for many of the nation's waterfowlers.
North America 's goose populations have increased for several reasons, but chief among them is that geese are not ducks. Most geese breed in the Arctic, not the prairies, where agriculture has made it a tough place to hatch an egg. For now, we're content to let the Arctic grow geese. Second, agriculture has provided geese with almost unlimited food supplies during winter. Historically, some goose populations were reduced by winter food shortages, which lowered survival rates. That limiting factor is completely gone for most geese. Finally, goose management has become increasingly sophisticated in recent years. Waterfowl biologists can accurately index the size of most populations and the hunting they will bear.
We now manage 25 distinct populations of geese in North America, and it is simply not possible to examine all these populations in a single report. Therefore, we'll concentrate on Canada geese and light geese, because they comprise most of the continent's total goose population. Canada geese (including the small varieties now referred to by the American Ornithologists' Union as cackling geese) are treated by flyway, while our discussion of light geese crosses flyway boundaries.
The Atlantic Flyway harbors three populations of Canada geese: Atlantic Canada geese (AP geese), North Atlantic Canada geese (NAP geese), and resident Canada geese (established through release programs). Most AP geese breed on Quebec 's Ungava Peninsula and winter near Chesapeake Bay, while NAP geese nest in Newfoundland and Labrador. Resident Canada geese breed and winter throughout the Atlantic Flyway.
The story of Canada geese in the Atlantic Flyway exemplifies the challenges faced by goose managers across the United States and Canada. It also reveals how managers have dealt with the complexities of goose harvest. The location of the "goose hunting capital of the world" is now open to debate, but in the 1970s and 1980s, that flag was firmly planted on Maryland 's Eastern Shore. Back then, most birds using Chesapeake Bay were part of the Atlantic population of Canada geese, the largest Canada goose population in North America at that time.
Prior to the 1990s, the population status of AP geese was determined from winter counts. But goose managers began to notice a disturbing trend in the late 1980s, when winter counts of geese in the Chesapeake region began to decline steadily. Fewer geese were turning up, even though spring counts of resident Canada geese in the Atlantic Flyway had increased from 400,000 birds in 1989 to nearly 800,000 birds by 1995. Many of these residents wintered alongside AP geese, yet winter counts of geese in traditional AP areas had declined by 40 percent.
Goose managers began to suspect that hunters were taking too many AP geese. The problem was that growing numbers of resident geese had masked the AP decline, which delayed changes in hunting regulations. Back in 1988, biologists conducted the first survey of nesting AP geese. The survey was an accurate measure of AP birds because no resident Canadas were present. The 1988 survey found 118,000 nesting pairs of geese. Recognizing the need to get an accurate estimate of AP birds, managers began annual breeding surveys of AP geese in 1993. Despite changes in hunting regulations, goose numbers in 1993 were down to 91,000 nesting pairs. The decline continued, and by 1995, only 29,000 pairs of nesting AP geese could be found. At that point, the season was closed.
Even today, it is hard to overestimate the disappointment many felt when hunting of AP geese ceased. But managers took two crucial steps that led to the birds' recovery. First, they recognized that resident Canada geese had muddied the waters and that breeding ground counts were necessary to track AP numbers accurately. Second, they established a breeding population objective that would help guide harvest management. In 2003, biologists counted 175,000 nesting pairs of AP geese, the highest on record.
This year, hunters on Maryland's Eastern Shore will enjoy an expanded 45-day season and two-goose limit. "Managers continue to closely monitor AP harvest rates with the goal of having a long-term sustainable harvest," said Larry Hindman, Maryland's waterfowl project manager who has been at the center of AP management for several years. Happily, he also mentioned that an early spring in Quebec had led to a great nesting year for AP birds. Once again the geese are back.
Biologists manage five populations of Canada geese in the Mississippi Flyway: the Eastern Prairie (EPP), Southern James Bay (SJBP), Mississippi Valley (MVP), Tallgrass Prairie (TGP), and the giant Canada goose population (residents). Except for giants, all these populations breed in the eastern Arctic. Birds from the TGP winter in both the Mississippi and Central flyways, and management responsibility for these geese is shared between the regions.
Goose management in the Mississippi Flyway historically focused on EPP, SJBP, and MVP geese. These birds traditionally wintered at a handful of refuges like Swan Lake, Missouri, where most of the EPP congregated. As a result, winter counts could be used to reliably monitor population changes. In 1969, biologists counted 600,000 wintering Canada geese throughout the flyway. Less than 10 percent of these birds were giant Canada geese. During the 1960s, hunters in the Mississippi Flyway harvested about 145,000 Canada geese per year.
By 2002, nearly 2.5 million Canada geese were surveyed during winter in the Mississippi Flyway, almost half of which were giants. At the same time, harvest of Canada geese in the flyway had increased sixfold. Although growing numbers of giants have dramatically increased hunting opportunities in the flyway, they have also brought unforeseen consequences. Giants now mix with migrant Canada geese throughout the Mississippi Flyway, and winter counts are no longer a reliable means for tracking changes in EPP, SJBP, and MVP geese. As a result, biologists now monitor these populations using counts from the breeding grounds.
Five populations of Canada geese are managed within the boundaries of the Central Flyway: the Tallgrass Prairie (TGPP), Shortgrass Prairie (SGPP), Hi-Line (HLP), Western Prairie (WPP), and Great Plains (GPP). Birds from the TGPP and SGPP nest in the Arctic, while birds from the HLP and WPP nest on the Canadian prairies and in parts of Montana, Wyoming, and Colorado. Most birds in the GPP originated from goose releases on the Canadian prairies and northern Great Plains. Interestingly, the SGPP is the only population of Canada geese in North America to have declined in the past decade, following a series of poor hatches caused by unfavorable weather conditions on their Arctic breeding grounds.
Winter counts of Canada geese in the Central Flyway have almost doubled from 680,000 in the early 1980s to 1.2 million birds in 2004. Not surprisingly, the harvest of Canada geese in the Central Flyway has also increased from less than 100,000 birds in 1965 to nearly 800,000 birds by 2001. Winter surveys do not account for all the geese in the flyway but are used to monitor the health of goose populations on key wintering areas.
Things can get a little complicated on the West Coast, and goose management in the Pacific Flyway is no exception. Waterfowl managers recognize seven subspecies of Canada geese in this flyway: Aleutian, cackling, dusky, lesser, Taverner's, Vancouver, and western Canada geese. Populations of most of these subspecies have increased, with total numbers going from 180,000 in the 1970s to more than 600,000 birds today. Duskies provide the only exception to this trend, and that takes us to the complicated part.
Duskies breed exclusively in Alaska's Copper River Delta and at one time were the only geese wintering in the Lower Columbia Basin of southwest Washington and northwest Oregon. In 1964, a major earthquake converted much of the Copper River Delta from low-lying marsh to upland. As a result, nests and goslings became easy prey for predators now wandering the much drier delta. By the 1970s, dusky numbers had fallen below 20,000 birds.
One solution was to close all hunting of dusky geese. But wintering duskies were no longer alone in the Lower Columbia Basin; they had been joined by six other subspecies of Canada geese. Growing goose numbers were a problem, especially for farmers running grass-seed operations. Because closed seasons were not an option, waterfowl managers devised an innovative idea to protect duskies and allow hunters to help control geese. Hunters must now pass a test to demonstrate their ability to distinguish duskies from other subspecies—on the wing! Without this permit, you can't hunt geese in the region.
Complicated hunting regulations aside, the most unique story in the Pacific Flyway belongs to the Aleutian Canada goose. Aleutians historically nested throughout Alaska's island chain. In the early 1900s, fur farmers began releasing arctic and red foxes onto these islands with predictable consequences. By the 1960s, the Aleutian population had plummeted to less than a thousand birds, and in 1973, Aleutians were formally protected under the Endangered Species Act.
Shortly thereafter, biologists began to identify areas of California and Oregon used by Aleutians during fall and winter. These areas were subsequently closed to all Canada goose hunting. At the same time, efforts to eradicate foxes on several nesting islands were beginning to pay off, and by 1990, the population had reached 7,000 birds. By 2001, Aleutians were declared fully recovered, and by 2002, bird numbers had topped 60,000. Remarkably, hunting of Aleutian geese was reinstated in the fall of 2003.
The final chapter in the Pacific Flyway is one of redistribution, and it involves the smallest of all geese, the cackling Canada goose. Historically, most cacklers migrated through the Klamath Basin on their way to wintering grounds in the Central Valley of California. In the 1960s, surveys of cacklers in the Klamath Basin routinely counted over 300,000 birds. By the early 1980s, the Klamath counts had fallen below 30,000 geese. The decline in cackler numbers probably resulted from spring subsistence hunting in Alaska and fall harvest in California, so harvest restrictions were adopted in the late 1970s. But that wasn't the entire story. Biologists suspected that some of the Klamath Basin decline was due to a shift in cackler distribution. They were right. Coordinated surveys throughout the Pacific Flyway revealed that most cacklers were now wintering in the Willamette Valley and Lower Columbia Basin of Washington and Oregon. With a better understanding of bird distribution and careful harvest management, the population of cacklers was restored to more than 200,000 birds.
The Light Geese
The term "light geese" includes Ross's geese, lesser snow geese, and greater snow geese. All three species nest in the Arctic. Ross's geese and lesser snow geese winter together in mixed flocks in both the Mississippi and Central flyways. As a result, biologists have combined light geese into two populations: the midcontinent population, wintering in Texas, Louisiana, and Arkansas, and the western Central Flyway population wintering in Colorado, New Mexico, and the Texas Panhandle.
Things are a little less confusing in other flyways. The only light geese in the Atlantic Flyway are greater snow geese, most of which winter along the coast from New Jersey to North Carolina. Most snow geese in the Pacific Flyway nest in the western Arctic or on Russia's Wrangel Island. Western Arctic birds winter in California and Mexico, while Wrangel Island geese use winter habitats in Washington's Puget Sound, Oregon, and California.
Light geese have been front and center these past few years. Much of this attention has focused on the midcontinent population where winter counts increased from less than a million birds in 1970 to almost 3 million birds by the late 1990s. While increases in midcontinent light geese have been a boon to U.S. hunters, the consequences for Arctic landscapes have been far less favorable. Light geese and their young feed in large groups. As bird numbers grew, the geese began to overgraze much of their Arctic breeding grounds. This led to changes in soil salinity and soil moisture that fundamentally altered Arctic plant communities, and not for the better. Some of the worst overgrazing occurred along the coast of Hudson Bay. The damage has been so extensive that biologists have concluded it will take hundreds of years for these Arctic areas to recover, if ever.
Waterfowl managers recognized that the continued destruction of these habitats would have dire consequences both for geese and other Arctic wildlife. The best way to reduce midcontinent light geese was to reduce the survival of adult geese, and the best way to do that was through increased hunting. In 1998, special conservation seasons were put in place to give hunters additional opportunities to harvest light geese. The goal of these extended seasons was to reduce the annual survival rate of adult geese below 80 percent. If that could be accomplished, goose numbers would come down, and the destruction of Arctic breeding grounds would be slowed.
So how have we been doing in our efforts to control light geese? According to Dr. Ray Alisauskas, a research scientist with the Canadian Wildlife Service who is analyzing survival rates of midcontinent light geese, preliminary results indicate that survival rates of adult geese have remained above the 80 percent target, despite recent increases in the total harvest of midcontinent geese. The struggle to control light geese continues.
Overpopulation of light geese isn't confined to the midcontinent. Greater snow geese in the Atlantic Flyway increased from less than 50,000 birds in the 1960s to nearly a million birds by 2003. Although these geese have yet to impact their Arctic breeding grounds, continued growth will eventually threaten the Arctic ecosystem. Lowering adult survival rates through increased harvest remains the best option.
Light goose populations elsewhere are also on the march. The western Central Flyway population has increased from 12,000 to 150,000 birds. Controlling light goose numbers may be the most significant challenge faced by waterfowl managers and hunters in the coming years. While harvests of some goose populations may have to be increased to prevent overabundant birds from damaging fragile tundra habitats, other goose populations may require harvest restrictions to help them bounce back during years when breeding success is poor. As waterfowl managers continue to learn more about the birds and refine their management strategies for different populations, the future for geese looks brighter than ever.
Dr. Mark Petrie, manager of conservation planning at DU's Pacific Northwest office, wishes to thank the many state, federal, and university biologists who provided information for this report.