Deer Hunter Harvest Surveys FAQ
Q. Why is hunter harvest data important?
Hunter harvest data provides the basis for monitoring hunted big game populations across North America. Monitoring harvest allows biologists and managers to determine if current levels of harvest are sustainable, evaluate where in the state harvest is occurring, and determine hunter success rates.
Q. How does the Department use data collected from harvest surveys?
Information provided by hunters is used to develop deer harvest estimates for all hunters throughout the state. Harvest estimates are then combined with other information such as aerial deer surveys, hunter observation surveys, input from landowners and Department field staff to develop annual recommendations for setting the following season’s license numbers.
Q. How does the Department collect harvest data?
For archery, gratis and deer-gun seasons the Department uses a probabilistic sampling design whereby surveys are sent to a stratified random sample of hunters according to the gender, species, and unit of the deer tag drawn. For muzzleloader and youth deer seasons, questionnaires are sent to every hunter. Selected hunters receive a questionnaire survey in the mail shortly after the deer season closes, and generally a follow up questionnaires is sent after 3 to 4 weeks to those hunters who have not returned their initial survey.
Q. Why does the Department send out surveys instead of using check stations?
A lot of states have voluntary, or even mandatory, reporting of deer harvest from successful hunters through physical check stations or via internet and telephone check-in systems. Although these reporting methods likely provide more data than questionnaires sent to a randomly selected sample of hunters, they come with important disadvantages.
Performing statistical assessments of harvest data from check stations is more difficult because: (1) the number of hunters that receive a license but do not go hunting is unknown, (2) the number of unsuccessful hunters is not known, because they are only required to report if they harvest a deer, and (3) the number of successful hunters who choose not to report the results of their hunt is not known. Therefore, harvest data from check stations potentially comes with additional problems not present in a probabilistically designed survey.
The surveys the Department uses measure unsuccessful hunters directly, and if there is bias from non-reporting, it can be dealt with by measuring the form and extent of non-response, or through statistical procedures (e.g. weighting). In addition to assessment disadvantages, physical check stations are costly to run and can be an inconvenient burden to hunters if the station is located far away from where the deer was harvested. Given the disadvantages associated with check stations the Department believes surveys provide a better estimate of deer harvest, are more cost-effective, and are more convenient for hunters.
Q. Isn't the Department missing out on important data by not sampling everyone?
No. Under a probabilistic sampling design, the Department does not need to collect everybody’s hunting activity, because it is assumed that the portion of hunters in the sample are representative to the rest of the hunters across North Dakota (this assumption is evaluated every couple of years). This allows the Department to estimate harvest for unsampled hunters based on harvest statistics from hunters who returned questionnaires. However, in order to ensure accurate estimates with low variability, more than 20,000 hunters are sampled each year, or about 40% of North Dakota deer hunters (2018).
Q. Why doesn't the Department send surveys out earlier in the season?
Deer surveys have been sent out in the same systematic way for almost 50 years. Making the survey available at the start of the season would represent a departure in the way the survey has been administered in the past. The concern is that this could introduce some sort of response bias in the results that manifests as an artificial increase or decrease in deer harvested. This would make it difficult to compare harvest data to past trends, thus invalidating one of the largest long-term data sets on deer harvest in North America.
Q. Why do hunters need to complete a survey even if they didn't shoot a deer?
Knowing if a hunter did not shoot a deer is just as valuable as knowing if they did. In fact, it is sometimes more desirable to know when and where hunters were unsuccessful, because this may suggest lower deer populations in those units. Moreover, there is other valuable information about hunting activity in addition to success, such as participation and effort. Participation data is used to estimate harvest for unsampled hunters, and effort data is used to compare harvest relatively across different hunting units and past years (i.e. total deer harvested per total days of hunting).
Q. Why aren't these surveys being done online?
The Department is currently (2019) working with the Biology Department at the University of North Dakota to find the best way to make deer surveys available online. Some hunters may have received these surveys as part of an ongoing research project. Preliminary findings suggest North Dakota hunters respond well to online surveys. Once the Department has a good understanding of how new modes of delivering surveys affect response rates and reporting biases, these new harvest surveys will be implemented more widely.