Golf Course or Wildlife Sanctuary?
A look at an Arizona Golf Course and the Future of Urban Wildlands
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Introduction
As the wild landscapes of the United States are being developed for people to live, work, and play, an increasing number of scientists are researching ways to engineer man-made spaces to accommodate wildlife. Stone Canyon Golf Course north of Tucson, Arizona is one such place where herpetologist and University of Arizona faculty member, Matt Goode is studying various reptile species on and off the green. Like a handful of other researchers around the world, Goode wonders if golf courses might be the right mix of man-made and wild habitat to comfortably accommodate both people and wildlife. This fall, I spent a few days with Goode at his field station to learn a little more about “golf course ecology”—three words I never thought I would use conjoined.

Amidst the nuances of their research, Goode and his peers keep coming back to two overarching ideas: “reconciliation ecology” and “ecological traps.” In an increasingly crowded world, reconciliation ecology has emerged as the study of how humans can share their habitat with non-human species (Rosenzweig 195). But these urban spaces turned wildlife sanctuaries are not without their pitfalls, and Goode is not alone in his fear that golf courses may in fact be ecological traps (Welz 2).

An ecological trap is a habitat (usually man-made) that is “low in quality for reproduction or survival and cannot sustain a population, yet it is preferred over other available, higher quality habitats (Donovan & Thompson 872). These traps often result in the reduced numbers of a species, or even its extinction. Ecological traps and reconciliation ecology are the two most significant, and opposing, schools of thought in golf course ecology. Unfortunately both are poorly understood, or at least very controversial. The result is an ongoing conversation between reconciliation ecologists and those who find the idea of ecological traps and the resulting biodiversity loss hardly worth a few golf courses. While persuasive arguments have been presented on both sides, current science indicates that golf courses may be able to maintain limited, but not complete, biodiversity. The question scientists are asking is, are we willing to accept a compromised biotic community existing in a matrix of fragmented habitats for the sake of a game? It’s becoming clear that if humans are to continue their pattern of growth, that kind of compromise could be increasingly common in the future.

Methods
Between August 26 and 28, I lived and worked with Matt Goode and his field assistant Mickey Parker at the Stone Canyon Golf Course. While there, I participated in every aspect of their work including the collecting of reptiles and amphibians by night and the entering of data by day. I also spoke at length with various representatives of the National Fish and Wildlife Foundation (NFWF) Wildlife Links program, USGA, and the PGA. In addition, I read a great many academic research papers from around the world on ecological traps, reconciliation ecology, and urban habitat of all kinds.

Discussion
Having “herped” (the catching of reptiles and amphibians for the purposes of science or curiosity) around the world, I realized that of all the exotic places I had hunted cold blooded critters, this was the first time I had done so on a golf course. It was also some of the best herping I had ever done! In addition, at the Stone Canyon Golf Course field station, herps were hunted from plush golf carts in the warm evenings after sunset. Sitting next to me and behind the wheel was Matt Goode, a full time herpetologist and faculty member of the University of Arizona. Among his many research projects around the world, studying golf course ecology on the Stone Canyon Golf Course is one of his most unique and cherished projects. While to many people, golf courses are synonymous with environmental degradation, Goode and other researchers around the world are finding that at least some species are adapting to the new habitat, and some are even thriving. But this new type of biology, a form of reconciliation ecology, is riddled with all the caveats and questions one would expect from a golf course turned wildlife sanctuary.

“There’s one,” I shrieked as a small Western diamondback rattlesnake froze in the cart’s headlights. “Crotalus atrox,” Goode said, referring to the snake’s Latin name, the only name used at his field station. I was starting to see that although Goode liked to crack a beer and go herping as much as the next guy (a large well stocked cooler occupied a permanent position in the cart), he was extremely serious about science.

The cart screeched to a halt and we hit the pavement running, snake bag and tongs in hand. As we circled the sleek critter, I could feel waves of water mist washing across my face. But for the road and cart with lights ablaze, the dark desert landscape around us looked entirely natural. Where was the water coming from? What an unusual thing in the desert! The snake summoned all its energy and made a break for the brush. I followed it off the pavement, crossing a network of camouflaged hoses all spewing water. This was an irrigated desert, and the mice and insects that scattered before me attested to the startling affects a little water can have in such an arid place. We bagged the snake and Goode marked the time: 19:45, the temperature: 30.2ºC and the humidity: 28%. As we walked back to the cart with the snake in a bag and the thrill of the hunt just beginning to wane, Goode explained that “wildlife in the desert is predicated on rainfall, and on a golf course it rains every day.” He went on to explain that the main focus of his study, Crotalus tigris (tiger rattlesnake), and Heloderma suspectum (gila monster) of a peripheral study, both eat rodents. Because of all the water and resulting seeding plants, rodents have become super abundant. Predictably, tiger rattlesnakes and others have changed their feeding habits to eat these energy-laden rodents almost exclusively, boosting their growth and reproductive rates as a result. Goode said that without a doubt, he finds more snakes and gilas on the course than on neighboring natural land. While he couldn’t speak to the prosperity of other species, the countless rodents, toads, lizards, snakes, tarantulas and myriad flying insects, we saw after just one lap around the 18-hole course convinced me that something besides the tiger rattlesnake was doing well.

But was all that abundance just a handful of species wildly proliferating while others were marginalized in their shrinking natural habitat? Or was all that water in the desert really a boon for everything as it appeared to my untrained eyes? It’s very complex Goode said, adding that “on new golf courses (5 years or newer) there is often the same abundance as in natural habitat. On middle-aged courses (10 years old) some species start to drop out. On older golf courses (20 years or older) there are far fewer species but those that are there are doing really well.” Beyond that insight, answers, as with all things in nature, prove illusive. After three days with Goode at his field station I returned home with one notebook full of quotes and two full of questions.

As I would later discover, the big question in golf course ecology is that of reconciliation ecology. The basic idea is this: In a world ever more overrun by people, how can we create spaces that are suitable for people and the greatest number of non-human species possible? (Rosenzweig 195). Some groups, most notably the Professional Golf Association (PGA) and the United States Golf Association (USGA), argue that golf courses embody such a compromise more so than other types of development like malls and housing. Other groups like the Wildlife Links Program of the National Fish and Wildlife Foundation (NFWF) are funding golf-course-related research (Goode is working under this funding) and have already funneled more than $1.4 million to scientists. In a phone interview with John Wright of NFWF, I was assured that the “program is science driven.” But NFWF is currently funded almost exclusively by USGA, causing some groups to question their objectivity. Meanwhile, Audubon International (not to be confused with the National Audubon Society) has created a golf course certification process, designating courses with a Gold, Silver, or Bronze rating depending on the “greenness” of the course. Newsome of the National Wildlife Federation (NWF) said in a 1996 interview in Planning that the initiative “gets courses to focus on things they wouldn’t otherwise pay attention to” (Salvesen 3). But since Audubon International does not actually visit courses, instead relying on photos and reports, the validity of the group has been questioned by the Sierra Club and the National Audubon Society (Salvesen 3).

Amidst the many certifications and advocacy groups, I found myself asking, “No matter how green a golf course, how can it be better than a natural landscape?” The answer is that it can’t, and few argue this point. But our world is one overrun with people, not with wilderness, and there seems to be some consensus that in certain situations, golf courses are a positive step for people, nature, and the ideals of reconciliation ecology. A frequently cited example is land that’s been degraded by mining or agriculture can make a wildlife-friendly golf course if built and managed sustainably. “In places like the UK or some places in the Northeast, the habitat is so poor that golf courses are biodiversity hotspots,” Goode told me. “But here [in Arizona], where the habitat is relatively pristine, they may be traps.” Ron Kendall of Clemson University wrote in a 1993 article, “There is no question that the best habitat is one that is left in a natural state. But if a golf course is going to be built how can we minimize its effects on the surrounding ecosystem?” (Kuznik 1). The simple answer seems to be that the beneficial affects of golf courses depends entirely on where they are and how they are built. This is where the regulatory agencies and forward-looking course owners are doing a reasonably good job. According to the Memphis, Tennessee newspaper, the Commercial Appeal, 28-year-old pop star and Tennessee native, Justin Timberlake, opened a new 303-acre course in north Memphis this July. Mirimichi Golf Course is considered one of the “greenest” in the nation and was the first to receive Audubon International’s “Classic Sanctuary” certification, their highest honor. Timberlake invested $16 million, which included a handful of Leadership in Energy and Environmental Design (LEED) certified buildings, and more have been promised.

While the green golf course movement slowly builds momentum, some are rejoicing while others still see problems. Many conservationists still reject the idea of reconciliation ecology, demanding better protection for parks and wilderness areas and the designation of new ones. The worry is that the global loss of biodiversity will not be mitigated by the principles of compromise inherent in reconciliation ecology. Instead the earth’s biodiversity will be reduced to a handful of generalist species that can migrate seamlessly into modified habitats, while others, perhaps the majority, are driven to extinction. Michael Rosenzweig, a leader in reconciliation ecology, has been widely criticized for his “amateur” approach to conservation. He suggested, for example, that the use of non-native plants in a salt-marsh bird sanctuary in Eilat, Israel is not problematic and that, because some species are benefited, the end result is satisfactory. Because so many practitioners of reconciliation ecology are non-scientists, there is great potential for the false idea to take root that any wildlife, native or not, is positive and should be fostered (Welz 2).

Another argument against reconciliation ecology points out that the ecological impact of golf has been significant, and its growth shows no sign of abating. Every year, 350 new courses are added to the 25,000 already in existence (Gange, Lindsay, & Schofield 1), each using more pesticides, herbicides, fungicides, and fertilizer than on any farm (9 pounds of fertilizer per acre) (Salvesen 1). While the average course uses 500,000–800,000 gallons of water per day, those in the arid Southwest can use as much as 1 million gallons per day (Salvesen 1). That’s enough water to fill a 10-foot-deep, football field-sized swimming pool every day. These courses are played by more than 27 million people in the U.S. alone (Kuznik 1), nearly 12% of the population.

Assuming we can find a way to sustainably support wildlife on golf courses, are they really the place for wild animals? Despite the frenzy for wildlife friendly golf courses, Diane Michelfelder points out in Valuing Wildlife Populations in Urban Habitats that, for many, wildlife actually make these spaces less “livable” for people (79). She later suggests that the presence of wildlife in urban areas is for some, like illegal aliens—not necessarily dangerous, but a nuisance nonetheless (80). In Maryland, the toll-free Maryland Nuisance Wildlife Information Line was established for local residents, while in Seattle, a Federal judge ordered 3,000 Canadian geese euthanized amidst fear of a public health hazard (Michelfelder 82-83). Greater interaction between people and wildlife sounds wonderful, but is the reality something people, and specifically golfers, are willing to live with?

In addition to the concerns of people, a growing body of evidence suggests that golf courses may not be suitable for wildlife in the first place. While no single study denies that a given species can be accommodated, each study points out a plethora of management changes that would have to be implemented to accommodate each species. While meeting a handful of these would be entirely possible, meeting all of them could preclude golf courses altogether. A golf course managed for all native species would not be a golf course, but untouched habitat. The following studies illustrate how significant the management challenges are for golf courses:

A 2006 study of spotted salamanders on a golf course in Southeast Connecticut showed that their movements were much greater than previously thought. While current statutes do protect breeding pools and 30.5 meters of the surrounding habitat, the authors found that because female spotted salamanders traveled so far, increasing the buffer to 164 meters would still protect just 82% of males and only 50% of females. A much more significant buffer of 370 meters would be required to protect virtually all males and about 95% of females. They also found that while adult spotted salamanders were not hesitant to cross fairways as wide as 80 meters, their rate of predation did increase significantly (McDonough & Paton 1167-1168). It would be difficult for golf course managers, who are working with a limited space, to justify setting aside so much land for one species of salamander.

A South African study of a new golf course and housing development in a pristine area of coastal scrubland had different but equally alarming findings. Their research showed that the plant regime changes resulting from watering and non-native plant introduction drove out natives and favored non-local and non-native generalist species. Most significantly though, they found the size of natural habitat “islands” interwoven with the course were key to the survival of native species: The bigger the better (Fox & Hockey 32). Since this study followed the development of the golf course from undisturbed habitat to manicured fairway, the researchers were able to observe the radical wildlife regime changes and displacement that took place.

A 2006 Arizona study looked into the assumption that migratory birds use man-made water features such as those found on golf courses. The researchers found that migratory birds did not benefit and local birds benefited only in times of drought and when foliage cover was sufficient near the water source (Lynn, Chambers, & Rosenstock 1). This study challenged a common conception among reconciliation ecologists that certain species are attracted to, and benefit from, urban habitat such as golf courses.

A 2007 study assessing the suitability of golf course ponds for amphibians found they were ideally suited to bullfrogs, which in many areas are invasive and extremely destructive to fish and other amphibian species. Bullfrogs, unlike virtually all Southwest amphibians, need permanent pools for their tadpoles to overwinter. Most natural Southwest pools dry out for a period of time each year, eliminating many amphibian predators. Chemical runoff proved another factor adversely affecting amphibians, according to their study. They concluded that while golf courses can be managed for amphibians and other wildlife, current management strategies will have to be modified. The authors call for a mandatory “hydro-period” of all ponds, meaning they would be allowed to go dry at least once per year, thus killing off non-native bullfrogs but not harming native species. They concluded that “intensely managed habitats such as golf courses could be incompatible with the conservation of native amphibians,” but acknowledged that “suitable habitat for wildlife and human use are not necessarily mutually exclusive” (Boone, Semlitch, & Mosby 173, 178). My own observations were consistent with these findings. On our nightly herp hunting trips around the golf course, Goode and I passed a large pond with a waterfall thundering somewhere beyond the reach of our headlights. The black water flowed around a collection of fake, or at least aesthetically placed rocks, and under a bridge, foaming like dish soap all the way. The smell was not exactly bleach but something equally caustic. I felt pity for any amphibian who had to live in such water. Indeed, I saw none and heard no evidence of their ruckus mating rituals.

A 2008 study of Big Cypress Fox Squirrels living on Southwest Florida golf courses found that the dense strata of non-native foliage created in some areas was disrupting the squirrel’s natural feeding behavior. In addition, the use of non-native trees reduced the available food for native species. They also found that while some courses were brimming with squirrels, their large numbers could be the result of migration from surrounding habitats, which were often being developed. The authors concluded that the currently accepted strategy for making golf courses wildlife friendly is woefully inadequate and generic in its approach: “Species may suffer lower fecundity, lower reproductive success and greater emigration rates when their habitat is within the matrix of a golf course” (Ditgen, Shepherd, & Humpgrey 412).

Each of the above studies shows that managing a golf course for a single species, or even a handful of species, is possible, but is difficult and expensive. They also show that managing a golf course for the myriad species that call any given natural landscape home is all but impossible.

Even where species seem to be thriving, there is always the proverbial elephant in the room—the ecological trap. A study of increased “edge habitat” along the San Pedro River in Southeast Arizona and its affect on mantids (praying mantis) looks at just this issue. Because of various anthropogenic changes along the river, the habitat is similar to the fragmentation that takes places on some desert golf courses. The researchers found that an increase in edge habitat can, for some species, act as an ecological trap. Their study found that mantids were lured to edge habitat for unknown reasons, and while reproduction rates rose, so too did egg case (oothecae) predation by birds. Though detailed studies remain to be completed and ecological traps are notoriously difficult to define, this and other studies seem to indicate that edge habitats are a common place for ecological traps to arise, and golf courses are full of them (Ries & Fegan 568, 570).

The simple but somehow elusive idea of the ecological trap was best defined by James Battin in his 2004 article, When Good Animals Love Bad Habitats, as “a low-quality habitat that animals prefer over other available habitats of higher quality” (1482). Though the concept was first described 30 years ago, (Ries et al. 567) it has not been until recently that it has been applied in anything but a theoretical context. Golf courses, housing developments, and other urban habitats have been a focus, but ecological traps can theoretically occur in nature as well. While few studies have specifically documented ecological traps on golf courses, many have addressed the issue peripherally. Because desert golf courses are so rich in water, they are ripe for ecological traps, which could have disastrous consequences for the wildlife that are lured there. While Goode is not studying ecological traps directly, he is keeping an eye out for their effects. “The snakes look good,” he said one night as we bagged another well-fed tiger rattlesnake, “but it might be a trap.”

Though no data exists to support the notion that there may be an ecological trap at the Stone Canyon Golf Course, a possible scenario might go like this: large amounts of water and invasive plant species create a huge amount of food for rodents. Rodent numbers boom. Rattlesnakes migrate onto the golf course to feed on the rodents. Their growth and reproduction rates increase due to prolific high-energy food. Rattlesnake numbers increase, but mortality from roads, mowers, chemicals, and a possible disease outbreak resulting in high populations densities kills many. The rate of mortality exceeds the rate of reproduction. Scientists do not recognize the trap because the golf course rattlesnake population remains steady or even increases due to more animals migrating onto the course from surrounding habitat. When the population in the surrounding habitat is no longer of a viable size, the species starts a rapid slide toward local or possibly total extinction.

While this scenario may seem overly dramatic and far-fetched, a real life example is being played out with the Cooper’s hawk, just south of the Stone Canyon Golf Course in Tucson. Hawks appear prolific in the city due largely to the number of pigeons and doves, which make up 84% of their diet. However, trichomoniasis is carried by both prey species and is fatal to Cooper’s hawks. Despite the large number of offspring they produce, their rate of mortality exceeds their rate of reproduction and yet their numbers increase. Researchers attribute this to migration from outside the city and fear a partial or total population collapse is imminent (Battin 1485).

In addition to ecological traps, golf course habitats are susceptible to many of the same problems as islands. Genetic load occurs where individuals of a given species experience “fitness” loss due to a lack of genetic diversity, often caused by a limited geographic space in which to exist and a reduced rate of immigration. The fragmented habitat usually found on golf courses also creates finite populations in danger of sinking bellow their “minimum viable population,” the smallest number of individuals that can exist without the threat of certain extinction.

Another obstacle to wildlife on golf courses is that, in a foreign habitat populated with non-native food and shelter, it is all but impossible for wildlife to choose habitat that will support them in the future. In a study on habitat selection, William Kristan noted, “Animals that select breeding territories face a complex forecasting problem, in which they must use the information available in the environment at the time when a choice is made to predict where they are most likely to survive and reproduce at some later time” (458). For an animal, finding food in a landscape of non-natives must be like an urbanite trying to feed himself in the wilderness.

As I walked around the Stone Canyon Golf Course one hot evening killing time between nightly herp forays, I watched three well-dressed older men play across a vibrant patch of green. Behind them, the Santa Catalina Mountains shimmered in the late afternoon heat. For more than a century, golf courses and golfers have increased throughout the world, leading many a pragmatic conservationist to embrace, if not wholeheartedly, the idea of golf courses as wildlife refuges. Most of them agree that in addition to helping golf course owners alter the way they manage and build courses, they also need to educate golfers. This includes changing their perception that a golf course should always be bright green, meticulously manicured, and full of trees that are flowering or at least green all year (Shapard 3). Perfectly illustrating the conflicting views of golfers and non-golfers, a 2002 survey conducted in Southeast England showed that 80% of golfers believe golf courses are a boon to the environment, while just 36% of non-golfers felt the same way (Gange et al. 63). Unique among ball sports, golf can actually embrace “natural” environments with roughs, natural features, and extensive areas designated “out of play.” These features are modifications of natural environments and could make the greening of golf a lot easier than, say, baseball. With 24%–40% of most golf courses designated “out of play” and some as high as 70% (Gange et al. 63), converting some golf courses to reasonably intact wildlife habitat is, according to some, entirely possible, saving owners money in maintenance costs in the process (Shapard 2). A testament to some efforts was the First European Bird Watching Open, held in 1998 across 116 courses in 18 European countries. Some 4,700 birds were seen representing 272 species with an average of just over 40 species seen per course (Gange et al. 67).

A Southeast Arizona study of burrowing owls showed them to be resilient to development of various kinds (Ellis & Conway 6), and that golf courses have been known to attract them. With their main source of food being rodents, it stands to reason that if all golf courses are as well populated with rodents as Stone Canyon, burrowing owls could do very well. Courtney Conway, an author of the study and faculty at the University of Arizona, said in a 2008 BioScience article “golfers and course managers take great pride in their burrowing owls. People want to play on courses that have the owls” (Cohn 1).

If ecological traps can be more thoroughly understood and avoided in the development of golf courses, the space could indeed be an ideal compromise between wild and urban. But like all compromises, there will be losers on both sides with the majority, I suspect, on the side of the natural world. Those species too delicate for the transition will be weeded out and the more resilient species will take their place leaving the planet, well, compromised.

Conclusion
Standing on a high rock outcropping between two multi-million dollar weekend homes on the final night of my stay, I thought about the unique type of landscape created by a golf course. Below me, stretching into the distance, were patches of bright green interwoven with the dull and decidedly less glamorous earth tones of the natural habitat. Over the past few days I had seen an abundance of life in the desert, and on a golf course of all places! But what had I really witnessed? A harmonious meeting of man and beast? A seamless melding of urban and wild? Or just another kind of development marginalizing wildlife? More importantly, were the creatures I had seen in all their glorious profusion blindly eating and breeding their way into an ecological trap? Only time would tell, but it was comforting to know that Goode and other equally dedicated scientists were on the case.

After a final night of herping, Goode and I drove back to the field station with bags full of writhing snakes and a cooler full of empty beer bottles. The night had been a success. Yet again I had seen more desert wildlife than on any other desert herping foray of my life. But even before I had delved into the details of ecological traps and the politics of golf and of urban environmental protection, I had an uneasy feeling about what I had seen. Looking for wildlife on the course reminded me more of a zoo, where one expects to see animals, rather than having to earn the experience. I barraged Goode with these questions. After swerving to miss a tarantula sauntering lazily across the path, he turned to me and pointedly answered my question with yet another question, “Is this an oasis or a mirage?” Only time will tell.

Works Cited
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Boone, Michelle D., Raymond D. Semlitsch, & Cory Mosby. Suitability of Golf Course Ponds for Amphibian Metamorphosis When Bullfrogs Are Removed. Conservation Biology 22.1 (2008). Print.

Ditgen, Rebecca S., John D. Shepherd, & Stephen R. Humphrey. Big Cypress Squirrel (Sciurus niger avicennia) Diet, Activity and Habitat Use on Golf Courses in Southwest Florida. The American Midland Naturalist 158.2 (2008). Print.

Donovan, T. M. & F. R. Thompson III. Modeling the Ecological Trap Hypothesis: a habitat and demographic analysis for migrant songbirds. Ecological Applications 11.3 (2001). Print.

Dwernychuk, L.W & D.A. Boag. Ducks Nesting in Association with Gulls-an Ecological Trap? Canadian Journal of Zoology. 1972. Print.

Ellis, Lisa A, Courtney J. Conway. Burrowing Owl Demography in Southeastern Arizona. 2002. Print.

Fox, Sarah-Jane C., & Phillip A. R. Hockey. Impacts of a South African Coastal Golf Estate on Shrubland Bird Communities. South African Journal of Science Jan/Feb (2007). Print.

Freedman, Daniel. Chávez Takes a Swing at Golf. The Wall Street Journal. 17 Aug. 2009.
<http://online.wsj.com/article/SB100014240529702046832045743542034 94729722.html>.

Gange, C. Alan, Della E. Lindsay, & J. Mike Schofield. The ecology of Golf Courses. Biologist 50.2 (2003). Print.

Goode, Matt. University of Arizona Faculty. I spoke to Goode in person multiple times between Aug 26 and 28, 2009 at the Stone Canyon Golf Course.

Kristan, William B. The Role of Habitat Selection Behavior in Population Dynamics: Source–Sink Systems and Ecological Traps. Oikos 103 (2003): 457–468. Print.

Kuznik, Frank. Charting A New Course. National Wildlife 31.5 (1993). Print.

Lynn, Janet C., Carol L. Chambers, & Steven S. Rosenstock. Use of Wildlife Water Developments by Birds in Southwest Arizona During Migration. Wildlife Society Bulletin 34.3 (2006). Print.

Ries, Leslie, & William F. Fagan. Habitat Edges as a Potential Ecological Trap for an Insect Predator. Ecological Entomology 28 (2003): 567–572. Print.

Rosenzweig, Mike. Win-Win Ecology: How The Earth's Species Can Survive In The Midst of Human Enterprise. New York: Oxford University Press, 2003. Print.

Salvesen, David. Greening up the Greens. Planning. 62.8 (1996). Print.

Shapard, Rob. Environment at the Fore Front: Keys for Greener Municipal Golf Courses. American City & Country 112.4 (1997). Print.

Welz, Adam. Winning Concept Seeks Work. Rev. of Win-Win Ecology by Michael Rosenzweig. Diversity and Distributions. 2004. Print.

Wright, John. National Fish and Wildlife Foundation. I spoke to Wright by phone on Sep 1, 2009.