Decision support for communities managing deer
Cayuga Heights (population ≈ 3,700) is a residential community adjacent to a major university. Cayuga Heights' persistence in developing a robust community-based deer management program has paid off. Using a combination of non-lethal and lethal approaches to deer management, the Village has reduced its deer population by 75% from its all-time high of 125 deer/square mile.
In 1998, a group of about a dozen village residents gathered hundreds of signatures on a petition calling for action by the New York State Department of Environmental Conservation (DEC) to address concerns about deer damage to gardens and landscape plantings. Later that year, the same individuals approached their village mayor to voice their concerns. The mayor officially sanctioned them as a committee to study the deer situation and develop recommendations for village trustees.
The deer committee formed a close working relationship with staff from the DEC, Cornell University (CU), and Cornell Cooperative Extension (CCE). The deer committee invited a local environmental educator with the CCE to provide it with information about techniques to reduce deer damage to landscape plants. At the committee’s invitation, this extension educator assisted with design and facilitation of citizen-involvement processes. Through her efforts, the deer committee came to have direct and repeated interactions with DEC staff and the state wildlife specialist for the CCE.
The extension educator worked with the deer committee to design a process for gathering public input. Eventually, the committee designed a process that included input from several sources: (1) two mail surveys of village property owners, (2) two studies of deer abundance and movements, (3) a committee fact-finding process, (4) two public meetings with village residents, and (5) discussions with invited technical experts on reproductive control in free-ranging deer.
The deer committee met 40 times between fall 1998 and May 2001 to gather information, define its situation, and deliberate about problems and potential responses to those problems. CCE personnel and DEC staff provided the committee with information about deer and deer management. DEC staff provided it with information about laws, statutes, and policies that would be brought into consideration if deer population reduction were recommended. To facilitate the deer committee’s work, the DEC provided partial funding for Cornell’s Human Dimensions Research Unit (HDRU) to survey village property owners about their experiences with deer, opinions on deer management, and preferred modes of involvement in deer management decisions. Staff associated with the HDRU, the CCE, and the DEC worked closely with the committee to synthesize and interpret survey findings and communicate those findings to village residents. With assistance from a range of technical experts, village residents defined problems, proposed management alternatives, and evaluated consequences of action alternatives.
Cayuga Heights officials have gone through two distinct decision making processes, the first occurring in 2001 and the second occurring in 2009.
By February 2001, the Deer Committee had documented that the majority of homeowners in the village were experiencing deer-related problems, desired relief from those problems, and wanted a reduction in the deer population. They recommended that the Village Trustees adopt a program of deer sterilization to reduce the population and then maintain that population at a reduced level. This option was available at no cost to the village at that time, because a team of researchers at Cornell had interest in the action as a research project, and an anonymous village resident was willing to provide matching research funds. The Village Trustees accepted these recommendations and an experimental deer sterilization program was conducted between 2002 and 2004. That work was followed by an immuno-contraceptive trial in 2005, which failed due to a faulty vaccine. The sterilization program produced a short-term, modest reduction of deer numbers, but the deer population continued to increase after the research ended.
Village residents’ concerns about deer-related problems, including deer-related vehicle collisions and exposure to tick-borne illnesses, continued to increase. In 2008, Village Trustees appointed a Deer Remediation Advisory Committee (DRAC) to review the current situation and recommend a course of action to the Village government. The Committee gathered information from experts in the field of deer management, and from residents, through open committee meetings and two public forums. The Committee shared data and findings via website and direct mailings to all households. The Committee made action recommendations to the Village Trustees (June 2009) based on a synthesis of gathered information. The Trustees approved the draft plan for the purpose of conducting a State Environmental Quality Review (SEQR).
The village hired a consulting firm to prepare a required Environmental Impact Statement (EIS), describing anticipated impacts that would occur if their plan of action was implemented. The final EIS was accepted by the Village Trustees in March 2011. The Trustees decided to proceed with the management plan recommended in the EIS document after accepting public comment on the document. The Village had to respond to and overcome a legal challenge before implementing the plan.
The management plan contained 3 objectives, to be achieved in sequential phases. Phase I called for surgical sterilization of at least 60 does within a two-year period. Phase II called for a deer cull over bait to further reduce the deer population. Phase III calls for maintenance of the deer herd at a target level of 15 deer mi2 through a combination of deer sterilization and culling. The Village hired a private consultant (White Buffalo) to implement the plan. A total of 152 does (100% of female deer) were sterilized between 2012 and 2013, and 5 more does were sterilized in 2016. The private consultant conducted a deer cull using archery equipment over bait sites in 2015 and 2016 (it took two years to lay the groundwork necessary to implement the cull). A total of 48 deer were removed in 2015 and 24 deer were removed in 2016.
Assessment, monitoring, and evaluation of both the human and biological dimensions of deer management have been prominent aspects of the Cayuga Heights case. Residents’ attitudes, experiences and management preferences have been assessed multiple times using rigorous quantitative survey methods. Multiple studies of deer density have been completed to estimate changes in deer density. Experimental deer reproductive technologies have been tested and assessed. Changes in rates of deer car collision, documented cases of Lyme disease, and extent of plant damage have been monitored.
The deer population density in the Village was estimated to be 125/mi2 in January 2013, 76/mi2 in January 2015 (two years after the first deer sterilization effort ended, but before the 2015 deer cull), 56/mi2 in spring 2015 (after the 2015 deer cull), and 38/mi2 in April 2016 (after the 2016 deer cull).