The study concluded that the deer management program improved the density and diversity of woody seedlings and saplings, but not necessarily in trees over 1-meter tall. This indicates that while the applied management strategy can improve forest regeneration, the longer-term effects of native recruitment are less certain. Chris Nagy, principal researcher on the project and Director of Research and Education at Mianus, shared a more in-depth perspective on the results and what it means for the future of deer management and further investigations.
What would you consider the most significant finding of the research?
This research really has both good news and bad news aspects. We were happy to see that an archery-based program can lead to measurable improvements in the growth of young trees, but simultaneously also shows that progress is very slow and takes a ton of investment of time and resources. The improvement in tree regeneration was significant but still not overwhelming, and even these moderate gains came with a serious price tag and a long time horizon.
What are the next steps for the deer management program and future research?
The findings of this analysis show that improvement has occurred but deer numbers need to be maintained at the current lowered density, or preferably lowered even further, for the gains in seedling density to translate to the next generation of mature trees. The big remaining question is whether the improvements we’ve documented are a sign of continued, gradual progress, or perhaps what we have seen after 15 years is the best we can hope for. We’ve chosen the optimistic outlook and will continue our deer management in the hope that conditions will continue to improve. Of course, we’ll have to assess that in 10 or so years, too.
Do you recommend this type of management plan for controlling deer browsing?
In our region, once you protect a piece of land from outright destruction or urban/suburban development, deer impacts are in the top three threats to forest conservation. Anyone managing land in this area has to consider deer impacts but to have a successful deer management program takes a huge investment. In your first couple of years of hunting, you will remove a good number of deer. However, as deer numbers decrease and those that are left become warier of humans-as-predators, it gets harder and harder to harvest deer. And this drop in efficiency occurs while deer are still far too numerous to stop removal.
You need to recruit good hunters with lots of free time that understand and embrace the conservation goals. You need to manage the hunters in terms of access, rules, and policies, and make sure they have a good experience hunting your land even though they can take more deer somewhere else. You also need to win over your community to the conservation goals of your program as well; this includes addressing, specifically, how killing animals is not contradictory to the mission of a “wildlife sanctuary.” And to throw even more work on the pile, deer management needs to be done in conjunction with invasive species control, habitat restoration for plants and whatever non-human predators are around, and ongoing assessment.
Is there anything else you want to highlight?
One thing everyone in this field has not figured out is how to scale up management programs such as ours to, for example, a county- or regional-scale effort. It is hard to envision how a program I described above would even be structured across a large area with many different communities, levels of urbanization, and land uses/ownerships. But this sort of scale is more relevant to deer and forest ecology, and if we do not approach the issue at this level, we will all just be struggling to manage isolated islands.
You can check out Mianus’s spotlight on the project here. Special thanks to Chris Nagy for sharing his perspectives on the research, and for a full copy of the publication, please contact him at firstname.lastname@example.org.