Canada Goose Populations

 

All Canada geese are not the same. Waterfowl managers recognize 20 populations of 11 subspecies of Canada geese in North America. Each population and subspecies is unique and is distinguished by characteristics such as morphology, distribution, migratory pathways, breeding and wintering grounds, and genetics. Research in and adjacent to Santee NWR will focus on SJBP geese as well as resident geese from the Atlantic Flyway Resident Population or AFRP. Resident, or temperate-nesting geese are those that do not take part in a seasonal migration to separate breeding and wintering grounds; instead they remain in relatively the same area throughout the year. They are usually of the race Branta canadensis maxima and/or Branta canadensis moffitti. The resident goose population is the largest population in the flyway, with numbers in the millions.


As resident goose populations increase, harvest of these birds has also increased. For example, in the 2000-2001 hunting season Canada geese were the most frequently harvested waterfowl species in Canada and the second most harvested species in the U.S. Also, Canada geese made up 16% of all the entire waterfowl harvested in the U.S. and Canada for this hunting season. So, while we are seeing an increase in the numbers of resident birds in our flyway, we are also seeing an increase in harvest of these birds. Harvest of these birds has increased 3.5% between 1962 and 2001. ~Schmidt, P.R. "Canada Geese in North America: Past Success and Future Challenges" - 2003 Canada Goose Symposium.

Interactions Between Resident Geese and Migratory Geese

Resident goose population growth can have negative effects on both humans and geese. Obviously there are numerous social challenges in dealing with the overabundance of geese when they begin to use areas such as golf courses or parks. However, the overabundance of resident birds can also effect the researchers that are trying to study the various goose populations. When resident birds share wintering grounds and/or migratory stop-over sites with migrant girds, they can reduce our ability to monitor population levels and harvest rates accurately. Some groups of resident geese may migrate north during the summer to molt. These birds are called molt-migrants. Some molt migrants travel to the northern breeding grounds in Ontario and Quebec. These breeding grounds are extremely important areas for migrant goose reproduction and nesting. When large numbers of molt-migrant geese arrive on the breeding grounds, they compete with northern-nesting birds and their young for food and resources. This may result in poor nesting success and/or decreased fledgling survival for migrant populations like SJBP. Also, when northern-nesting birds and molt-migrant birds are grouped together, it is difficult to tell them apart, and this can result in skewed population estimates by researchers.

Canada Geese in South Carolina

Comparing all states in the Atlantic Flyway, the southern-most states of  NC, SC, GA and FL have experienced a gradual decline in their wintering migrant flocks (See graph of Santee NWR goose flock decline). As a result of these declines in the migrant wintering flock, goose hunting seasons in South Carolina began to close in the 1980's.  In 1992, the resident population had increased enough to open a hunting season on these birds.  However, Clarendon County was closed to hunting of resident birds in order to avoid harvest of SJBP geese.  This is still the case today, as Clarendon county remains closed to goose harvest.  Since extensive knowledge of habitat use and home range of wintering geese in this area is unknown, researchers hope to gather data that will provide the South Carolina Department of Natural Resources with the information they need to make management decisions pertaining to harvest.