Harvest Surveys

Duck wings

Harvest Surveys

The first nationwide Hunter Success Survey (HSS), occurred in the US in 1952 and produced estimates of harvest for each of the four Flyways. Estimates for individual states were first made in 1960 and Canada began a national harvest survey in 1967 as well. Since Canada requires a federal permit to hunt waterfowl, they have a suitable database to derive a sampling frame for harvest surveys. However, prior to 1998, the only federal requirement to hunt waterfowl in the U.S was to buy a Migratory Bird Hunting and Conservation Stamp (Duck Stamp). People who purchased duck stamps formed the sampling frame for all migratory bird hunters in the U.S. (Please see the paragraph on HIP below). At the end of the season, hunters were asked to report where they hunted, the number of days hunted, and the number of ducks and geese taken. In the first years of the survey in the U.S., hunters were also asked to list their harvest of individual species of waterfowl. However, since 1961 in the U.S. and 1968 in Canada, the composition of the harvest for individual species of waterfowl is determined by another survey called the Parts Collection Survey (PCS).

A sample of hunters are asked to send one wing from each duck and the tail and primary wing feathers of each goose harvested to respective Flyways in the U.S., with a similar procedure being implemented in Canada. Hunters report the location and date of harvest; while biologists determine species, sex, and age, using criteria described by Sam Carney for duck wings. The feather characteristics of geese are used to determine species and age, but cannot be used to determine sex.

Concerns about the efficiencies of using the duck stamp in the U.S. to provide a sound sampling frame of hunters, and the realized need to accurately estimate harvest of all migratory game birds such as; doves, snipe, and woodcock, brought about significant changes beginning in the early 1990’s. The first year of the Harvest Information Program (HIP) was in 1992 and three states participated in a pilot program. Under HIP, all migratory game bird hunters must register in the state where they intend to hunt. Hunters provide their name and address and answer broad questions regarding their harvest the previous year. The information that hunters initially provide while registering is not used to determine harvest, but allows the USFWS stratify the sample, so all groups of migratory birds hunters are properly sampled depending on the types of migratory birds they hunt.

The requirement to register under HIP was phased in across the country and hunters in all states (except Hawaii) were required to register by 1998. Currently, a sample of hunters are contacted directly by the USFWS after they register for HIP and are asked to keep track of their harvest and hunting activity during the season. The cooperation of hunters remains a critical component of obtaining good harvest estimates. Much more information about HIP is available at the harvest surveys website provided by the USFWS.

Results of the HIP survey are combined with that from the PCS and band recoveries to provide an overall picture of the waterfowl harvest. In addition, these data can provide an index of what the composition (the age and sex ratios for each species) of the fall flight was, providing a check of the data collected during the breeding season.

A separate mail questionnaire is used to estimate sandhill crane harvest in the Central Flyway and those methods are explained in the sandhill crane survey section of this website.

Waterfowl Wing Bee

Since 1961, a sample of waterfowl hunters are asked every year to send a wing from each duck and the tail and tips of the outermost primary feathers from each goose harvested to each Flyway. That location in the Central Flyway is currently the Flint Hills National Wildlife Refuge near Emporia, KS. When the wings and goose feathers arrive at the refuge, they are separated by species and stored in a large freezer.

In February, biologists from the USFWS and state wildlife agencies, along with other volunteers, assemble for three to five days to evaluate duck wings and goose feathers. For ducks, the species, age, and sex of each bird harvested can be determined. Each table of people working on duck wings has a checker assigned to it, an experienced person who has received special training and whose accuracy has been carefully checked. The checker reviews determinations made by workers at the table regarding age and sex of every duck wing, which allows workers to continually improve their skills as the Wing Bee progresses, since feedback is instantaneous. Many copies of Sam Carney's book, Species, Age and Sex Identification of Ducks Using Wing Plumage, can be found open to one page or another throughout the work area.

The sex of geese cannot be determined at the Wing Bee, but feather wear and other characteristics are used to determine if the goose was a "young of the year" (hatched the previous spring) or an adult. In addition, the length of the central tail feather for Canada geese is obtained to determine if it was part of the Central Flyway Arctic Nesting populations (small races) or part of the Western Prairie or Great Plains population (large races). Similar to the duck tables, a checker reviews the species and age determinations of other workers at the tables to ensure accuracy.

Recently, about 19,000 duck wings and 3,500 goose tails have been processed annually by workers at the Central Flyway Wing Bee.

Each bird’s data are entered together with the information provided by the hunter (i.e., date, time, state, and county of harvest). Some of this information is entered into a computer using a bar code reader at the Wing Bee allowing it to be immediately available to managers. Ultimately, the data is combined with that from other Flyways and becomes part of the national USFWS Parts Collection Survey database.

The Wing Bee provides the data used to compute the species composition of the duck (e.g., the percent of the total duck harvest that was mallards) and goose harvest, and therefore information on the harvest pressure exerted on each species. The data also provides an estimate of age ratios for both ducks and geese, which is used to gauge the success of the previous year’s reproduction.