An empirical analysis of hunter response to chronic wasting disease in Alberta

ABSTRACT

Chronic wasting disease (CWD) has impacted wildlife management in Canada. An integral partner in CWD management is the hunting community. This article empirically explored the response of Alberta mule deer hunters to CWD by modeling license application trends in areas where CWD has been positively detected in wild cervids. The relationship between resident draw applications and covariates of CWD prevalence, hunting quotas, draw success rates, licenses, and environmental indicators was examined with a fixed effects (FE) regression model. Results indicated that hunters are continuing to apply to hunt mule deer in areas with CWD and this relationship is not statistically impacted by the increasing prevalence of CWD. This outcome may be because CWD prevalence in Alberta is relatively low (but increasing), which is consistent with the literature indicating that few hunters avoid CWD zones until prevalence increases dramatically. Results also suggest that hunter-based strategies remain effective options for management.

KEYWORDS:

• Chronic wasting disease
• hunting
• mule deer
• wildlife disease
• wildlife management

Notes

1. The Ministry and its departments have gone through multiple name changes since 1998; this is the current name.

2. Alberta is divided into WMUs and the wildlife within each individual unit are managed by AEP according to the regulations in the Alberta Wildlife Act and Regulations. The five WMUs referenced are 150, 151, 234, 256, and 500.

3. Although the total number of mandatory CWD submission WMUs increased from 39 to 42 in 2018, to maintain consistency only the 37 mandatory submission WMUs identified in 2017 were included in the analysis.

4. Although AEP cervid licensing is based on “antlered” and “antlerless” categories, the CWD monitoring program reports results as “male” and “female.”

5. Please note that white WMUs in the Figure 3 (license applications) are outside of the study area, whereas white WMUs in Figure 4 (CWD prevalence) include WMUs without CWD in addition to the WMUs outside the study area as identified in Figure 3.

6. This trend occurred in the absence of a specific strategy by AEP to increase mule deer licenses to control CWD until 2018. Although it could partially explain the increase in license sales observed in 2018, hunter engagement prior to this was primarily for surveillance purposes.

7. Variables are lagged because the information of these variables from the previous years are released prior to draw applications in June and the hunting season in November.

8. In other words, ${\beta }_1$ is the best linear unbiased estimator (Greene, 2012).

9. If the unobserved individual-specific variables are uncorrelated with the CWD and X, a random effects model can be used in this case (Greene, 2012).

10. No qualitative change to the reported results were found when year dummy variables were added.

11. For comparison, all five models were repeated using a CWD presence/absence dummy covariate instead of the CWD prevalence. This approach yielded similar results.

12. Due to the aggregate nature of the data, demographic information such as income, age, education, etc. was not included in the analysis.

13. As noted previously, releasing more mule deer tags was not a CWD management strategy of AEP until 2018.

14. Alberta hunting draw applications and licenses have been increasing in recent years (AEP, 2019a), contrary to Alberta trends in the 1990s (Boxall et al., 2001) and more recent North American trends (Tack et al., 2018). However, this trend could be influenced by increasing number of areas and species to be put on draws.

15. The 37 WMUs in the study area are considered excellent mule deer hunting locations in Alberta (Alberta Professional Outfitters Society [APOS], 2017).

16. To determine whether the results were consistent for both meat hunters (primarily female mule deer) and trophy hunters (primarily male mule deer), Model 5 was repeated by sex. The results remained consistent with those presented in the pooled analysis, with two exceptions: (a) the quota of tags released became positive and significant for antlered mule deer and temperature was not significant for antlerless mule deer applications. The impact of CWD was positive, but insignificant across all models.

17. The total population of Alberta was also tested in the analysis here, but removed in favor of a covariate for cervid draw licenses.

18. However, the efficacy of these management options has been questioned in some states as CWD can spread faster than hunters can reduce herds (Erickson et al., 2019; Rosatte et al., 2014). Despite these concerns, these management approaches remain viable and may be publicly acceptable options for wildlife managers.

Additional information

Funding

This work was supported by the Alberta Prion Research Institute (Alberta Innovates).