Vassar Farm and Ecological Preserve

Vassar College

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Deer Management Memorandum

June 12, 2009

To:  Senior Officers
From:  Vassar Farm Oversight Committee
Re:  Deer Management Findings and Recommendations

The Vassar Farm and Ecological Preserve is 530 acres of open space that is used for education, research, athletics, food production, composting, and recreation. This space is a valuable resource to both Vassar College and the surrounding community.  The majority of this land is managed as an ecological preserve whose mission is to protect and preserve the ecological diversity of the land to ensure that its educational value will be maintained in perpetuity. The Vassar Ecological Preserve promotes increased understanding and appreciation of the natural systems on the preserve through field-based education and research.

The detrimental impacts of deer overpopulation on the forested areas of the preserve have been apparent for many years.  Preliminary studies of the impacts of deer overpopulation on the preserve indicate that there is no regeneration of native trees.  The overpopulation of deer is driving the ecological trajectory of the preserve.  The future of the preserve and its value as an educational resource will be determined by whether we manage the deer population.   In order to act in accordance with the mission of the Ecological Preserve a deer management plan must be adopted.  Reducing the number of deer would improve the health of the forest community, decrease the incidence of tick born diseases, reduce deer/car collisions, reduce the economic losses associated with deer browse on landscaping, and help adjoining landowners who are struggling with these issues.   Members of the committee and experts in deer management have investigated all known options for controlling the deer population.

We seek the support of the senior officers to implement our recommendations for a deer management plan on the Vassar Ecological Preserve.  In order to meet our current timeline (Please see Implementation section below), we need to begin applying for the necessary state, town and city permits this summer and therefore urge you to authorize moving forward with the implementation of the plan by mid-summer 2009.  Restricted funds from The Swain Endowment are allocated for the maintenance of the ecological preserve as an educational resource.  These funds could be utilized to cover the costs associated with implementing and sustaining this management plan. 

Principal Recommendations

Phase I: Sharp shooting - contract with White-Buffalo Inc.  Reduce deer population from current 100 animals on the Preserve to 15 deer.  Donate venison to organizations for the hungry.

Phase II: Maintain deer population annually by controlled hunt (method not set - feasibility study will be carried out to determine most effective method.  Methods may include controlled access bow hunting or sharpshooting by experts).

Supporting Documentation

Overview of research findings:

• The highly detrimental ecological impact of deer overpopulation on forest ecosystems has been conclusively established by years of research.  The impact on natural systems is dramatic.  Deer affect the growth and survival of native herbs, shrubs, and tree species causing changes in forest composition.  High densities of deer prevent forest regeneration and impact forest structure.  There are a variety of harmful, cascading effects of these changes on native insects, birds, and mammals (Cote et al. 2004, US Forest Service 2008). One important conclusion drawn by Cote et al. (2004) is that changes wrought by deer overabundance may be irreversible.  For Vassar College, these impacts, which have been documented for many deer species in habitats around the world, mean that the teaching, research, and aesthetic value of the outdoor laboratory of the Vassar Farm and Ecological Preserve are in jeopardy.  Action to control deer on the Vassar campus is needed to stop the harmful effects of deer and begin the process of forest recovery.
• High densities of deer are also a significant threat to human health. Although the white-footed mouse and other small mammals are largely responsible for infecting ticks with the bacterium that causes Lyme disease, there is evidence that a deer management program can lead to a reduction in the incidence of Lyme disease.   A study of a deer-culling program in Connecticut has shown that there is a strong correlation between the incidence of Lyme disease and deer population (Kilpatrick and LaBonte, 2003).  According to the New York State Department of Health, the incidence rate of Lyme disease in 2007 was much higher in Dutchess county (202.87 infections/100,000 people) than in the rest of upstate New York (37.7 infections/100,000 people).  Implementing a deer management strategy may reduce the risk of people contracting tick borne diseases while working outdoors on campus and in the surrounding community.
• High numbers of deer/car collisions are the cause of additional health and economic impacts in our community.  The number of automobile accidents involving deer increases with deer density, traffic, and habitat fragmentation (Groot Bruinderink & Hazebroek 1996).  According to the DMV, the annual number of collisions involving deer between 2002 and 2006 has tripled in New York, growing from 6,104 to 18,932.  In 2006, there were 868 deer car collisions in Dutchess County alone.  Acting to implement a deer management plan should reduce deer car collisions.  A reduction in collisions would prevent injuries, death, and economic losses in our community.
• The review by Cote et al. concluded that overabundance of deer causes "major economic losses in forestry, agriculture, and transportation."  Managing the deer population would reduce browse damage to plantings and allow the community to reduce their use of repellants and fences. Reducing the deer pressure would remove a major constraint on the new master plan for campus.
• Several institutions of interest have been managing deer using a variety of methods:
  • Locust Grove uses fencing and drives the deer off of their property.  The fence requires constant maintenance and deer often find a way in. 
  • The Cary Institute of Ecosystem Studies uses controlled access hunting to manage deer and their program is very successful. 
  • Swarthmore College has also been working on developing a deer management plan.  They intend to manage their population using sharp shooting and are trying to incorporate a hunting component into their plan. 

Deer Population Estimates:  Infrared flyovers took place on the night of December 16, 2004 and again on January 19, 2009 to determine the total number of deer on our property and how the population is changing over time.  There were 223 deer on campus in 2004 and 115 deer in 2009.  During the count taken in 2009, 100 of the deer were on the ecological preserve.  The infrared flyover is a snapshot and the numbers should be interpreted as being the minimum number of deer that were in and around Vassar College at the time the count was made.  There can be considerable variation in the number of deer found during aerial infrared flyovers because of deer movement to neighboring areas, limitations of the technology, and natural variations in population.  Both counts show very high densities of deer, with the 2009 data translating to approximately 125 deer per square mile, a density well above that recommended by the DEC.  To prevent negative impacts to biodiversity, the DEC recommends deer densities below 15 animals per sq. mile (Clarke, 2009).

Primary Goal:  Our primary goal is to reduce the deer density to a level where forest regeneration can occur and biodiversity is promoted. According to the NYSDEC Wildlife Biologist, a density below 30 deer per square mile allows for forest regeneration and a density below 15 deer per square mile prevents negative impacts to biodiversity (Clarke, 2009).  We estimate that reducing and maintaining the density of deer on the preserve to approximately 20 deer per square mile should achieve these goals.  In order to achieve that density, there should be approximately 15 deer residing on the Vassar Farm and Ecological Preserve.

Secondary Goals:  We have several secondary goals for our deer management plan.  Managing the deer population will make Vassar College and the surrounding community a healthier place to live by reducing the incidence of tick borne diseases and reducing the number of deer/car collisions.  Deer management should also mitigate the destruction of the ornamental landscape on campus and in the surrounding community. We hope to help reduce hunger in our community by donating venison to local people in need.

Recommendations: Primary and Alternative Approaches

• Professional sharp shooting is a humane, safe, and effective way to obtain the initial population reduction required to achieve a healthy density of deer (White Buffalo Inc. 2004).  It is the only method for the initial population reduction that will allow us to meet our management goals safely.  Sharp shooting may also be the most effective tool to maintain the population.  The population would need to be maintained with sharp shooting every two years (DeNicola pers. com. 2009). (Please see Implementation section below: Summer 2009 for permitting information)
• It is unlikely that controlled access archery hunting would be able to achieve the initial population reduction within a time frame that would meet our management goals (White Buffalo Inc. 2004, Ray Winchcombe pers. com. 2009).  Controlled access archery hunting could be an effective tool for the maintenance phase of our management plan.  We could select a group of 3-4 individuals that were prescreened for proficiency and competence (DeNicola pers. com. 2009). The hunters would be trained and informed of our management objectives on an annual basis.  The locations that they would be permitted to hunt would be selected for their safety and distance from trails and residences.  We would encourage the same select group of individuals to return to the property to help manage the deer population annually.  Controlled access archery hunting would probably need to be supplemented with sharp shooting periodically to keep the population at levels low enough to meet our management goals.  Controlled access hunting has the potential to reduce the long-term costs of maintaining a healthy density of deer.  We propose that White Buffalo do a study to examine the feasibility of controlled access archery hunting on the preserve.
• If a non-lethal method for maintenance is desired, fencing could help to maintain the population after the initial population reduction.   The initial cost of installing a fence would be high and the fence would require constant maintenance. A fence may be negatively perceived by the local community utilizing the preserve and fence vandalism costs may be incurred.  A fence would also limit the access of other wildlife species through this area.
• Neither fertility control or trap and transport appear to be feasible strategies for reducing the size of the current herd.  Currently, fertility control is difficult, expensive, illegal (not registered by the EPA) and unproven (DeNicola 2004).  We will continue to monitor developments in fertility control.  If the longevity and delivery techniques are improved, we should revisit this method as an option for population maintenance.  Trapping often injures the animals and few survive release into their new habitats (DeNicola 2004).  Fear of disease transmission and widespread deer overpopulation makes it unlikely that any locations would be willing to receive deer.

Costs: The estimated initial cost of reducing The Vassar Preserve deer population to a sustainable level using professional sharpshooters would be approximately $25,500  (White Buffalo Inc. 2009). White Buffalo will perform a feasibility assessment for determining a maintenance program for the preserve that will cost an additional $4,500.* 

The Swain Endowment could be used to cover the full cost of deer population reduction and management at the current rate. Deer removed during management will be donated to Hunters for the Hungry.  They will process and distribute the meat to local people in need at no cost to Vassar College.

*The estimated cost of the initial phase of management has been reduced to between $8,000 and $10,000.  This is due to a change in scope of the operation and site details that make implementation of our plan easier.  We expect that the initial cull will remove 50-70 deer.  It is unlikely we will be able to reach our goal during the first year of management.  The feasibility study of maintenance options will be postponed.  New York State law currently prohibits using archery off-season as a management technique.  Archery is currently the only alternative to sharp shooting for population maintenance (DeNicola pers. com. Updated 12/2/2009).

To fence the Preserve, Adams Fences Inc. estimates $143,615.00 for installation and fence material.  Not included in this cost estimate is site preparation for the fence or fence maintenance.

Community Response:  The Farm Oversight Committee understands that deer management is a complex issue and will elicit a variety of responses in students, faculty, staff, community members, and the broader public.  We have been engaged in an open discussion about deer management and have found that the response has been positive once people have been educated about the issues associated with deer overpopulation. We have notified both town and city officials that we are investigating potential solutions to our deer overpopulation and have invited the major of the City of Poughkeepsie, John C. Tkazyik, and the Town of Poughkeepsie Supervisor, Pat Myers, to meet with us.  Ms. Myers accepted our invitation and expressed support for our plans.  Students who have studied the issue have come to the conclusion that deer management is a necessary step.  Overall, adjoining property owners have been supportive of managing the deer population.  Some individuals have even offered to sponsor the removal of a few deer.  Managing deer at the college will help alleviate the problems that the community is experiencing because of the deer overpopulation and the anger that some residents have for Vassar's lack of action on this issue.   Vassar should be perceived as a good neighbor for helping the community to deal with this problem.  In an urban setting, large landholders are the only members of the community that have the ability to begin to address this issue.  We hope that through education and discussion that the majority of the community will be supportive of Vassar College implementing a deer management plan.

Developing a Plan Through Education and Research:

• In January 2009, we hosted a lecture and discussion where ecologists discussed the causes of deer overpopulation, the ecological impacts of deer overpopulation, Lyme Disease, and examples of herbivore overpopulation throughout the world. Troy Weldy also discussed the management options and the decision making process that The Nature Conservancy has followed on TNC lands in urban areas. This meeting was followed by a public discussion of the issue. The audience was made up of approximately 80 faculty, administrators, students, town officials, and community members. The audience was engaged by the issue and wanted to participate in further discussions. The Miscellany News (January 28, 2009) published an article on this forum.
• In April 2009, we held a public forum where a panel of deer management professionals spoke about the ecological impacts of deer at their sites and the management methods that they have adopted. The discussion included the problems with overabundant deer, immunocontraception, management experiences at other local institutions, and the management options that make sense for our community. Lethal removal and fencing were identified as potential techniques by the panel. The regulatory and political obstacles of implementing a deer management plan were also discussed. Approximately 35 Vassar and Poughkeepsie community members participated in this discussion of Vassar's deer management options. The Miscellany News (April 26, 2009) published an article on this forum as well and the overall response to the article has been positive.
• At the 2009 NYS Deer Summit held in April organized by the eastern NY chapter of The Nature Conservancy, Vassar College was used as a case study of how to advance management at a typical site. Failed attempts at advancing management, integration of deer overpopulation and management into education, and ideas on how we are attempting to advance deer management were presented by Keri Van Camp to an audience of deer management professionals. The summit attendees participated in a discussion of the management options that are available to Vassar College and the challenges that we will face during the implementation of a management plan. Sharpshooting, archery, and fencing were discussed as appropriate management tools for our site.
• Deer management is a local problem that has the complexity that allows it to be considered by many disciplines. The consideration of this problem has been integrated into the classroom. Philosophy students have written about the ethics of deer management as part of a class assignment. Students in the summer Institute for the Gifted drafted a deer management plan as their summer project.
• Carrie Levine recently completed her senior thesis that examined the role that seed banks and deer management play in forest composition and structure. Her research compared data from long term deer exclosures at two local institutions with different management plans to baseline data from the deer exclosures on the Vassar Ecological Preserve. Her study shows that sapling abundance and species richness were decreased where deer were present at high densities. She found that a good deer management program could allow forests to rebound in twelve years. Her thesis concluded, " The results from the exclosure experiments at the neighboring Rockefeller and Cary Institute of Ecosystem Studies sites imply that deer management is crucial for maintaining biodiversity at the preserve, and ensuring the continuation of a functioning successional forest system".

Implementation

1. Summer 2009
   1. Apply to the NYSDEC for deer management permits.
   2. Clearly outline our program with the Town and City Administration to ensure that we meet all Town and City ordinance and regulations. Apply for a variance to allow for the discharge of a firearm within city limits.
   3. Contact residences bordering the college property by letter to outline the nature of the problem, consequences of inaction, and a possible scenario of a control plan. We should include a form that they could sign to permit the discharge of firearms within 500 feet of their residence. This would allow us more freedom to design and implement a successful management plan.
2. Fall 2009
   1. The deer committee will continue to interface with the Vassar and local communities and a final forum will be held to discuss the approved management plan. Educational signage and flyers will be produced, announcing the plan and its implementation.
3. January 2010
   1. Communicate to neighbors and farm users that the farm should not be entered during the time that the deer management program is being implemented. Post signs at all entry points to the farm. If security is a concern, we could also post people at all major routes of entry.
   2. Implement the deer management program consisting of bait stations and professional sharpshooters.
   3. Immediately following the completion of the initial cull, have White Buffalo conduct a study to examine the feasibility of controlled access archery hunting on the preserve.
   4. The meat will be processed and distributed by Kevin Haight (Hunters for the Hungry). This organization coordinates the distribution of venison to homeless shelters, soup kitchens, Meals on Wheels, and other people in need of help in our community.

Bibliography

• Clarke, K. 2009. Personal Communication, NYSDEC Wildlife Biologist
• Côté, S.D., T.P. Rooney, J.-P. Tremblay, C. Dussault and D.M. Waller. 2004. Ecological impacts of deer overabundance, Annu. Rev. Ecol. Evol. Syst. 35 (2004), pp. 113-147
• DeNicola, A. 2009. Personal Communication, White Buffalo Inc.Groot Bruinderink GWTA, Hazebroek E. 1996. Ungulate traffic collisions in Europe. Conserv. Biol. 10: 1059-67Kilpatrick, Howard J. and Andrew M. LaBonte. 2003. Deer hunting in a residential community:  the communities perspective.  Wildlife Society Bulletin 31: 340-348
• US Forest Service. 2008.  Impacts of White-tailed Deer Overabundance in Forest Ecosystems:  An Overview.  Northeastern Area State and Private Forestry, Forest Service, U.S. Department of Agriculture, Durham, NH. 8pp.
• Winchcombe, R.  2009.  Personal Communication, Cary Institute of Ecosystem Studies.