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Executive Summary

The Gambier Island Sea Ranch (GISR) is a hobby farm that aims to provide education on the practice of raising animals with the goal of helping community members form a better understanding of how their food is produced (R. Boulter, personal communication, November 7, 2014). Recently at the GISR, multiple predator attacks have resulted in a significant loss of their livestock, the most severe of which have been pine marten attacks on broiler chickens. To combat these issues, two anti-predator methods were explored that are lawful and beneficial to the animals, the ranch, and the residents. By using a mixed approach of qualitative and quantitative methods, including key informant interviews and direct observation, we were able to develop two predator control strategies. We believe these strategies will be the most effective at solving the issues of predation while maintaining the values and purpose of the GISR. We recommend that GISR purchases a llama to act as a guard animal or relocates the chicken house to an open field and builds an electric fence around the perimeter in order to deter predatory attacks on livestock. Based on the information collected from academic literature and informant interviews, the GISR faces many challenges in order to maintain their small-scale farm. Some limitations to the implementation of our suggested predator control plan include budget, lack of information and training strategies, and lack of infrastructure (Sossidou et al., 2013). However, the implementation of the suggested strategies is expected to minimize or fully eradicate the continued losses of livestock in an economical, ethical, lawful and respectful manner within the GISR farm. By providing key tools and research-based evidence to enhance the GISR’s daily farming practices, this will enhance the residents’ food literacy. Food literacy, defined as having the knowledge, skills, and behaviours to navigate one’s food system and ultimately, having the empowerment to determine their food system are all elements that can reinforce the GISR’s purpose, values and success of the farm (Vidgen and Gallegos, 2014).


Gambier Island Sea Ranch
Gambier Island Sea Ranch

We are a team of eight students currently studying various disciplines within the Land and Food Systems faculty. Our community partner is the Gambier Island Sea Ranch (GISR), a nonprofit, hobby farm run by a strata community looking to promote a sustainable community food system, which “[improves] the health of the community, environment, and individuals over time, involving a collaborative effort ... to build locally based, self-reliant food systems and economies” (McCullum, 2005). The values of the farm include environmental consciousness and exemplary animal husbandry while being research and evidence based, inclusive, visible, and educational (R. Boutler, personal communication, November 7, 2014). The farm runs on solar power and stream fed water. The purpose of the farm is to educate both children and adults about farm practices and provide community members with meat products that come from well-treated and ethically raised animals (R. Boutler, personal communication, November 7, 2014). This involvement with the farm enhances their food literacy and food sovereignty, “a critical alternative to the concept of food security ... broadly defined as the right of local peoples to control their own food systems” (Wittman, 2011, p. 87). Because the GISR is secluded on an island, they rely on barges to transport the animals, feed for livestock, and people to and from the island. In this sense, the GISR food system is a small food system dependent on the larger lower mainland food system. A visual of the following with highlights of important connections can be seen at the following website:

In recent years, many farm animals have been attacked by predators such as cougars, wolves, pine martens, bears, eagles, and racoons. This past season, the farm lost 53 chickens to predator attacks, mainly by a pine marten (B. Katz, personal communication, September 28, 2014). If unaddressed, these attacks could greatly impact the economic success of the farm and their ability to continue promoting a sustainable farm system model. To determine how to combat these issues, we proposed the following questions: What are two methods to control predator activity towards the broiler chickens around the Gambier Island Sea Ranch? Are these methods beneficial to the animals, beneficial to the ranch and residents of the island and lawful?


Pig Lot
Flagged Fencing for Chickens

Theoretical Framework
The objectives of the GISR shaped the ways in which we determined our research methods. As an educational farm, the GISR helps its community members to better understand the sourcing and labour required to produce food through experiential practices (R.Boulter, personal communication, November 7, 2014). It is important that our predator control options are economical, ethical, lawful, and respectful. In this way, solutions could not be costly, detrimental to animal welfare, illegal, or contradict GISR objectives and/or morals. These desired qualities were the general guidelines we employed to construct an effective anti-predator plan.

The following factors were indicators of the need for intervention: large portion of livestock lost, concern amongst the community members, and struggle to reach a consensus on an approach to control predation (Table 1). University students were the chosen resource to develop a plan as a result of the educational premise of the farm as well as the monetary savings saved from hiring students instead of professionals.

Key Factors Concepts Variables Relationships
  • Predators
  • Predator impact
  • Potential solutions
  • Objectives of GISR:
  1. Educational intentions
  2. Budget constraints
  3. Animal welfare
  4. Environmental favorability
  • Economical
  • Ethical
  • Lawful
  • Respectful
  • Opinions of community members
  • Varying predators for different animals
  • Animal size and predator impact (eg. Piglets at risk but pigs are so large, over 300 pounds, that predators no longer affect them)
  • Maintenance and labour on the ranch (most community members spend little time at GISR over the winter months, there are only two farm managers)
  • Transport costs
  • Suggest biological solutions to avoid negative impacts on environment, animals, predators, biodiversity and for GISR to operate in symphony with the island community and native species

Table 1. Different contextual aspects of the farm concerning our research, including key factors, concepts, variables and relationships.

Methodological Approach
We chose a mixed methods approach when conducting our research as we decided this would be the most effective way to provide us with a complete, holistic view of the project and the problem to analyze. This approach entailed both qualitative and quantitative research and helped us thoroughly understand the research problem. We could then integrate information from scholarly sources and contextual information from site visits and community partners, while still allowing the research to be both generalizable and detailed. This helped us consider other perspectives and communities such as the indigenous people of the island, conservation groups, and islands trust. Using the results of other studies combined with the contextual characteristics of the GISR, we were able to determine which two anti-predator methods were most likely to be effective. The factors to consider include: animals most affected by predation; ranch budget; location of fields, rivers and trees; availability of fences and infrastructure, and farm owners’ values and desires. The quantitative research included key informant interviews with farm management, direct observation that took place during our visit to the farm, and background literature research on island farming and the GISR. Research was conducted via online resources and databases, and live, key interviews with stakeholders and participant observations of GISR (Table 2a). This approach was advantageous as we were able to find current trends of farm animal populations while maintaining an objective perspective for community members. Additionally, the facts acquired were likely valid and reliable which provides further insight on whether the proposed solution will be effective or ineffective. The qualitative research included in-person interviews with farm management and community members as well as direct observation, which took place during our visit to the farm. It also included researching literature pertaining to both the predators’ behaviour as well as potential anti-predator solutions. In order to conduct our qualitative research, key interview research questions regarding the farm were formulated and sent to Rosalie Boutler, our GISR representative (Table 2b).

Quantitative Research Questions Qualitative Research Questions
  • What is the size of the farm, the fields, and how many animals are present at the ranch?
  • What is the ratio of animals before and after the predator attacks?
  • How many people are affected by predation?
  • What is the budget for the anti-predator plan?
  • What is the size of the fenced infrastructure protecting the chicken, turkeys and broilers?
  • How many animals are still there (ratio/percentage of before and after their budget for this predator plan?
  • How many people are affected by the predation (do all permanent residents buy food from this farm as they are their major resource?)
  • Who works on the farm?
  • What modes of transport are used to bring materials to the island?
  • What policies should we consider in our development of a predator plan?
  • Is there one predator we should focus on?
  • How would you define the purpose of the farm?
  • How long has the farm been established?
  • What were the community's hopes and intentions for the farm when it began and how have those perspectives of the farm changed since then?
  • What is the long term vision of the farm?
  • What actions are the ranch taking to make it self-sustaining?
  • Is the water used for the farm brought over or is rain water collected?
  • What are the pen sizes for the pigs, turkey, chicken, and the overall size of the farmed land?

Table 2a Quantitative and 2b. Qualitative key interview questions.

This mixed approach aided our understanding of the complexity of the predator problem by enabling us to draw relationships between systems. We were able to ask questions through numerous skype calls and emails that were directed to the predator issue as well as our overarching research question. In addition, this approach allowed for specificity of information acquisition because much of the quantitative research is not focused on GISR, but must be collected, analyzed, and adjusted. Initially, we thought interviewing community members would be sufficient but once it was determined the community was in need of an objective, unbiased predator plan, we concluded any interviews conducted should be supplemented with quantitative research findings. After finding information from peer-reviewed articles, we consolidated all our findings into various Google Drive documents based on the predator control plans and relevant information to support the suggestions. With weekly meetings, we communicated new information and made edits to our documents accordingly with the goal of building a strong predator control plan for the GISR in mind.

Our research evolved significantly over time, primarily, narrowing our research scope. Initially, our intention was to examine every predator at the GISR and develop a strategy to mitigate all predator concerns of community members. However, due to time and economic constraints, we felt it would be most effective for us to evaluate the livestock facing the highest predator risk and the predator causing this. In doing so, we conducted a qualitative analysis and concluded broiler chickens were most at risk and the most prominent predator was the pine marten.

Our Community-Based Learning and Research provided group members with an understanding of the Ranch through quantitative analysis and, as a result, all group members acquired useful knowledge about operating a small scale farm and the issues farmers may face in the Pacific Northwest. Direct observation and interviews with farm management, in addition to our volunteer hours, allowed group members to gain hands-on experience with small scale livestock production and agriculture on an island.


Findings from Interviews
From our online interviews with Rosalie Boulter, we found the farm is a hobby farm with its own identity and gained a better understanding of the farm’s purpose and values mentioned earlier. In addition, this interview placed the aforementioned context of the food system of the farm, including the inputs, outputs, key actors and connections between each. Boulter mentioned there is currently no specific long term vision for the farm as they are constantly improving practices and adapting to community needs. In addition, Boulter (October 30, 2014) had requested our anti-predator plan for poultry to be integratable on a larger scale to protect other livestock species. She mentioned that although pine marten, eagle, and raccoons are the current biggest threats to poultry, other predator species such as coyotes, wolves, and cougars could also pose a risk (R. Boulter, personal communication, October 30, 2014). We then used online databases to research what other challenges island farmers are facing, which are budget, lack of information and training strategies, and lack of infrastructure, and took this into consideration when developing the anti-predator plan to prevent further difficulties (Sossidou et al., 2013).

Anti-Predator Findings - Research Based
Two key anti-predator strategies were found with evidence from academic literature and practitioners including guard llamas and relocation with electric fencing.

Guard Llamas
Introducing guard llamas to the GISR farm is perceived to be an efficient method to protect livestock without having to sacrifice free-ranging practices. Llamas have been found to efficiently reduce the loss of sheep within a pasture of 250 acres from 11% to a mere 1% (National Sustainable Agriculture Information Service, 2002). They do not cause harm towards the sheep. Instead, they develop an innate sense of protection towards these animals once a paddock for their territory and a bond with the livestock have been established. In situations where predators are present on farm grounds, they produce warning sounds, attack the predator, or lead the flock away (National Geographic, 2003) . The use of llamas has been historically effective with protecting flocks of sheep, however chicken farms have also turned to llamas. A chicken farm in Northern Ireland faced a loss of 300 hens due to hen-hunting foxes but has since resolved their issue by introducing a pair of guard llamas (Cassidy, 2005).

Their physiological build, predominantly their height, weight and speed, are assets to detecting intruders at a greater distance. Cavalcanti and Knowlton (1998) states that heavier llamas correlated with a higher degree of aggressiveness and thus may be more self-confident against medium-sized predators, including coyotes. Standing at 6 feet tall and weighing 250 lbs, they are grass grazers and chew their food as cud (National Geographic, 2003). Moreover, they require little water, making them dependable and durable animals. It is recommended llamas have a three-sided shelter for protection against hot sun, wind, rain and snow. Fencing made from board, electric wire or field wire are appropriate for llamas, however barbed wires are unacceptable (Brown, R., & Brown., L, 2011). While guard llamas have many benefits, a few disadvantages include jumping the fence and injuring or harassing lambs. Llamas have a long working life of 10-15 years and require minimal training of 4-6 weeks. Based on the biological nature of llamas to be herd-dependent animals, many farm owners recommend keeping at least two (Brown, R., & Brown., L, 2011). From an economical perspective, gelded male llamas typically range from $300-800 with an annual maintenance cost of around $100. For this reason, 80% producers believe llamas are the most effective in reducing predation losses, and 85% indicate they would recommend guard llamas (Brown, R., & Brown., L, 2011).

The method of chicken house relocation is based on the prevention of pine marten attacks, though it would also aid in the prevention of other small wild animal attacks. The pine marten, also named the American Marten, is usually found in forests with a distribution in conifer-dominated forest throughout British Columbia, including Vancouver Island and other small coastal islands (Hatler, Blood & Beal, 2003). Zalewski, Jedrzejewski and Jedrzejewska (2004) found that martens cover an average of 5.1 kilometres per day, and has a home range of several square kilometres in which it captures prey; furthermore, martens are accomplished swimmers. Thus, live trapping the martens and releasing them in the forest farther away or off the island is likely to be an ineffective method of control. Manzo, Bartolommei, Rowcliffe and Cozzolino (2012) has shown pine martens prefer to spend the majority of their time in woodland rather than cultivated fields. They make their nests in the forest as it offers protection from predators and provides a good source of food that allows them to survive and reproduce (Birks, Messenger & Halliwell, 2005). On Gambier Island, there is a very high population of eagles and hawks, both of which are natural predators of small mammals like pine martens. In order to avoid these predators, it is likely pine martens avoid open areas, preferring the cover of trees and vegetation. Based on these natural behaviours, relocating the position of the chicken house to an open, un-forested area could reduce the likelihood of attack. The advantages are that they are economical for the farm owners and effective in reducing the likelihood of attack from the pine martens. Crossing open ground without coverage will increase the possibility of a marten becoming prey for one of its natural predators, deterring their attempt to access the chicken house and the roof at night time. It was made apparent during a stakeholder interview that a pine marten had gained access to the chicken house at night by climbing on the roof from a tree. We believe moving the chicken house would help prevent a reoccurrence. On the other hand, this open, non-forested area will also expose the chickens to those same aerial predators such as eagles and hawks, allowing them to prey on the chickens. A covered area surrounding the chicken house in the new location, like the existing barbed grid, would help the chickens avoid eagle attacks in the daytime, while still leaving a wide band of open ground all around it to deter the martens. Exposure to sun on the open ground may also increase heat stress which can, in its worst cases, lead to death (Damanhouri, & Tayeb, 1992). Using the appropriate cover and diet supplementation may help with these problems.

Electric Fencing
In addition to relocation, installing an electric fence to further deter predators from attacking the chickens is recommended. An electric fence is more lightweight, easier to install than traditional fences, and more effective than a non-electric fence in preventing small predators like the pine marten, or larger predators such as coyotes, from entering the house or field (Hansen, 2013). The electric fence produces an electric shock at direct contact which could be used to repel returning predators as they become discomforted by the shocks (Hansen, 2013). Linhart, Roberts and Dasch (1981) observed that coyote attacks were completely eliminated from several test fields after electric fences were installed. In another study where farmers had predation issues from raccoons, foxes, and minks, they used 5.1cm-spaced chicken wire fencing charged with electricity to deter these animals from entering their fields (Sargeant & Kruse & Afton, 1974). For an effective barrier against coyotes and other large animals, we suggest the fence be constructed of a 1.5 metre high-tensile mesh with alternating ground rods and charged wires. High-tensile fences are highly recommended as they use high quality, smooth wires that could be electrified (Hansen, 2013). A higher fence with overhanging wires on top can prevent predators from jumping over the fence (The Vincent Wildlife Trust, 2013). Research and general retail sources indicate materials required for an electric fence are more inexpensive than non-electric fencing (Hanson, 2013 & Edwards, 2012). In non-irrigated soil, ground rods and wires should be connected to each energizer and be driven at least 5.5 feet into the soil and placed approximately 10 feet apart (Pratt, 1991). These numbers may vary with the geography and size of the field. Ground rods and wires are required to complete the circuit of electricity from the fence, through the ground, and to the predators (Pratt, 1991). In non-irrigated land, dry or frozen conditions may render the electric circulation ineffective, which is why ground rods and wires are necessary to enhance and complete the circuit (Ministry of Agriculture, 1996). To be continuous with the GISR’s goal towards sustainability, solar panels could be used in place of the energizers (Hansen, 2013).

Regular inspection and on-going maintenance is required to insure the fence is working at all times as it can be shorted out by natural occurrences such as lightning, or physically damaged (Ministry of Agriculture, 1996). A testing device is also required to measure the voltage to insure the effectiveness of the fence or the lethality of it if the voltage is too high. Linhart et al. (1982) recommended to include barbed wire at ground level, and barbed wire overhanging the top to help deter predators that will climb or dig under fences. However, the BC Ministry of Agriculture (1996) does not suggest the use of barbed wire in electric fences due to safety concerns over humans or animals becoming caught in the wires. There could be serious harm or even death if an animal or human is unable to separate from the charged electric fence (Ministry of Agriculture, 1996).


GISR Farm Chickens

Introducing llamas could potentially be a solution to control predators on the GISR farm and would not compromise their values of being an economically conscious and sustainable farm. By doing so, livestock are able to continue with free-ranging practices upholding their value of excellent animal husbandry practices. The suggestion of guard llamas is ideal in this context as it is a ‘biological’ intervention rather than a direct human intervention meaning we are not using lethal depredation control techniques. Guards llamas pose minimal risk to their livestock due to their altruistic behaviour. Economically, they are inexpensive in comparison to the amount of livestock lost over the past two years. As a low maintenance farm animal, more care and effort can be placed into other areas of the farm. For example, their fecal matter may be used as high-quality compost and improve the farm land for plant growth (National Geographic, 2003). In a larger global food system scale, this is a prime example of how to approach ecological problems in a sustainable and feasible way. The relocation and the electric fence methods we found are designed around the living habits and biological characteristics of the pine marten. We need to begin by thinking about the biological nature and behaviour of animals and consider their needs and environment. Using a ‘bottom-up’ approach will benefit the GISR community and support their vision in leading a sustainable farm.

The significance of our findings is they can provide the farm with a method to avoid losses in their livestock due to island predators. In terms of the food system, these strategies can help ensure the island residents will be able to maintain a farm that provides a unique educational experience and good quality foods for its community members. If these methods are implemented and successful, they could be a potential solution for other farms with similar issues. If the methods are unsuccessful, we suggest the farm owners consider shifting to a focus on growing crops instead of raising livestock or accept the high loss in animals and continue to provide the educational farming experience to the community. Limitations in our methods include geographic differences and biological differences. All the findings we have are not for the farm on the island; they came from studies in Australia, the United States and the United Kingdom. The data may not be reproducible on this island and may cause significant differences from our expectations. Moreover, we did not have enough time to run an experiment on the island to prove our methods and our limited amount of visits may not have been enough to design a perfect anti-predator plan.

We believe the GISR’s goal goes beyond the anti-predator plan as they are trying to promote food literacy, defined as improving everyday practices, having the knowledge skills and tools, and ultimately being empowered to determine their food system (Vidgen and Gallegos, 2014). With our findings, we hope to further improve the current food literacy of the community by providing knowledge and farming skills that can improve the GISR’s food system overall. We can agree with DePuis and Goodman (2005) that localism can be the reason for the rise of more sustainable food networks, and it has a pluralistic approach to rural development. Agroecology had a major role in this project as we evaluated the GISR’s ecological and farm management processes for further improvement (Mendez et al., 2014). However, this predator plan project was developed in an objective point of view. Because we were unable to hear all residents’ perspectives and suggestions, the effect of our results may be hindered. Not integrating a major knowledge system’s ideas, the community members, in our research may lead to disjointedness within the community if the ideas are not accepted by all.


Summarizing our research findings, information from personal interviews, and discussion, we recommend two methods to improve the serious loss of broiler chickens on GISR. The first one is to bring in llamas into the farm as a guard animal. We think llamas would be able to protect livestock such as broiler chickens because of their natural protective behavior and economical value. On the ecological aspect, introducing llamas is similar to adding a natural “barrier” in the interaction between predators and farm animals. The second method, to relocate the broiler chickens and reinforce with fencing, was suggested to combat the main predator-prey relationship between the pine marten and broiler chickens. Having learned that pine martens climbed and jumped over fences with the help of trees, we believe moving the broiler chicken field away from the woods would be a good solution. In addition, the grid cover could be used to prevent broiler chicken losses from aerial predators. A shelter, on the other hand, could protect these chickens at night.

We believe these suggested methods can efficiently control predator activities towards broiler chickens and ultimately other livestock on the GISR. Referring back to our research question, these two methods should be beneficial to both farm animals and residents, and are contextual and lawful. These two methods provide tools and knowledge to further enhance food literacy and subsequently improve food security for the Gambier Island Sea Ranch.


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