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The story does not start here, but this will provide the reader with the types of information that guide my decisions regarding what species can do well out side. Fifteen years back my wife and I went to Arizona for two months. I had arranged for a friend to look after my turtle and tortoise collection; she always did a good job so I had little need for concern. In late February when we returned I noticed that there were only two Herman’s tortoises in a container that for years had housed three. Several days later I asked about the missing one, as she taught various nature classes and was always borrowing this and that for the students to see. “No when I first come out I noticed there were only two, I just assumed one had died.” When I left I knew there were three and for several days I pondered the mystery. Then it dawned on me in my haste to clean every thing before our trip I must have inadvertently thrown one out with the old bedding. Ugh. Then I realized that for the two months we’d been gone no one would have emptied the trash. Maybe I could at least get some piece of mind by looking through the trash cans. I found him in the third can, rolled up in newspaper and the discarded cypress mulch bedding. How sad, and how incredibly dull of me. It took a few minutes to realize he was still alive. Alive, and that January and February were one of the coldest recorded in my 20 or so years of living in Raleigh, North Carolina, with lots of well below freezing nights. I warmed him up gradually and within a few days he was active, eating and butting the females. Starting that spring my Herman’s tortoise collection (they all are of the type from Yugoslavia, now regarded as a separate species Testudo boettgeri) got moved to a year-round outdoor pen. That tortoise is still with us, the pen is larger and the herd is bigger, but he is doing fine and contributing his DNA to additional Herman’s tortoises. They hibernate from late October through late March and seem to thrive in there current enclosure. I relayed this experience to a number of friends and soon found that they too responded by putting their Herman’s tortoises outside. We learn from experiences, and fortunately this was a favorable one. I try to keep our turtles and tortoises outside for as much of the year as our season will allow. Almost everyone who has kept turtles for any period of time has observed the benefits from housing tortoises and freshwater turtles in modest sized to large outdoor enclosures The advantages to keeping turtles outside are many and can benefit both the person overseeing the turtles and the turtles themselves. In general, outdoor enclosures are easier to clean and one does not need to be concerned with heating, cooling, humidity, and lighting. From the turtle’s perspective outside pens are generally larger, have more natural conditions, and if set up properly have a wider range of micro-environments. Sunlight is important for many turtles for processing calcium, preventing skin fungus and similar ailments, and allowing a wider range of thermal regulatory options. Changes in day length apparently trigger reproductive behavior and physiological readiness in many captive turtles. The longer the turtles can be maintained out side the greater the advantage, and many will start cycling their reproductive behavior to fit local seasonal weather variations. Reproductive out-put of turtles kept outside seems better than those maintained indoors throughout the year, but there are a lot of variables here. Additionally, well cared for captive turtles often double, triple, and some even quadruple clutch. Comparing reproductive records of well cared for captive turtles established in the right enclosures indicates that reproductive out-put is better than in wild populations studied to date. Not only can captives consistently produce more clutches per year, annual variations in egg productions in wild turtles often exhibit off years is not an issue.
Disadvantages: Predators are always a problem. Dog, raccoons, grey foxes, and various avian predators (red-shouldered hawks, fish crows, and barred owls are the worst here in eastern North Carolina) can cause problems. Even small birds such as Carolina wrens will take hatchlings. Norway rats can be a problem in urban settings and adult bullfrogs often move into outdoor ponds. Electric fencing, or trained guard dogs work well for four-legged predators, and plastic meshing will discourage birds. Trapping predators is only a temporary fix as new ones will eventually move into unoccupied territories and replace them. As I write this I am dealing with a very cleaver, electric fence jumping, grey fox, he does not bother the turtles, but he and I race to see who first gets to their eggs. Do not leave excessive amounts of uneaten turtle food in the outdoor enclosures overnight. If neighborhood children and less-than-honest turtle hobbyists are a concern, locks and security cameras may be needed. The working theme is exclusion, as one cannot control what lives outside outdoor turtle pens. Adult bullfrogs will need to be captured and removed, as they are quite capable of eating hatchling turtles. Ants may prey on eggs or emerging hatchlings. Parasites both internal and external are more difficult to detect and manage than they are when turtles and tortoises are kept in typical indoor set ups. Turtles with open sores are more likely to have infections that go undetected or are made more severe by ants and flies. Theft is always a consideration, and obviously turtles in back yards are more vulnerable to theft and vandalism than ones retained inside. A closed-circuit video security system provides a good investment. Natural disasters (flooding, high wind events, etc.) may allow turtles to escape, drown, and fallen limbs can take out protective electric fencing. It is much more difficult to find eggs and hatchlings in outdoor enclosures. Turtles, despite their shelled bodies, are real escape artists and individual turtles occasionally breach pens with well-designed fencing. Trees and limbs falling in enclosures can provide ladders of escape. Dogs and other predators remove turtles even when not able to negotiate their armor and release them outside your enclosures. Plants growing inside the pens can eventually provide escape routes for turtles. This includes dense bunches of grasses and sedges which the turtles will climb. Weather extremes or unexpected major storms may make it necessary to bring turtles inside from time to time for protection.
Precautions Electric fencing is great. When set up properly it works and it is inexpensive. Just think like a modest-sized four-legged something (dog or raccoon), then think like a rat. Each enclosure is different so there is no way to make a diagram as to how to do this. Look for natural and then man-made open gateways to the enclosure such as trees with overhanging limbs, rain-spouts, and other avenues of possible access. Get the fence up and on before you add turtles, and try to keep excess food from accumulating. In some neighborhoods electric fencing may not be allowed, but where it can be installed it works and it self educates local predators, pets and dull neighborhood children. Additional security may be necessary it theft is perceived to be a problem. Security lights with motion detectors, security cameras, and outdoor fencing with locked gates may give you and the turtle’s piece of mind. Ants are a problem in that they sometimes kill and consume hatchlings as they are first coming out of their shells or ants will swarm on the open sores of terrestrial species. This is a real problem here in the southeast where the imported red fire ant now abounds. Eggs are best dug up and incubated under controlled conditions. Hopefully no one will have turtles with open sores. However, normally not all clutches are found, and turtles can inflict injuries on one another. Typical ant poisons and baits concern me as it could end up on the turtle’s food, and the half-life of some is longer than it takes ants to re-colonize. I have been using small amounts of gasoline to combat the ants, and pour about a shot glass full on each ant mound. Gasoline has a small molecule and evaporates quickly, while the ant colony is typically knocked out within 20 minutes. Nesting sites should be provided for the turtles, and sometime they actually use them. Often eggs show up in the strangest places. Each species has preferences for nesting; usually a high sandy loam placed in a sunny spot will attract the females to the site. Once they start using it, or once you figure out where the turtles prefer to nest, you will find them using the same general sites year after year. Be aware of the possibility of second clutches about four to six weeks after the first. Constant checking of pens for problems with the enclosure itself and the overall health of the turtles is recommended. This does not imply that every turtle needs to be handled every day. I usually limited this to two times a year (before and after hibernation). But one should make sure that they are moving about on a normal basis and that their food is being eaten. I often tell visitors that they are not seeing turtles because healthy turtles stay concealed for much of the day. If the enclosure is set up properly and the turtles are fed they rather much take care of themselves. Good fencing of enclosures does two key things, it keeps turtles and tortoises in and keeps other stuff out. One needs to keep this in mind when designing fences. I bury my fences 12 to 18 inches, this is mostly to keep moles and similar animals out of the pens. (It works most of the time). I have never had any problems with turtles digging out and escaping. Even burrowing species such as gopher tortoises do not present problems, while their burrows may indeed go under the fence, their burrow entrances are inside the enclosure. Lips on the upper edge of the fencing is a must, turtles are good climbers. Wood turtles are notorious climbers, but so are most aquatic Asian turtles. I often see them 10 or 12 inches above the substrate hanging on the fence trying to climb out. On several occasions I have had wild free ranging spotted turtles get into my pens as the lips do not prevent entry from turtles climbing in from the outside. Walls of enclosures can be solid of made of wire mesh. Solid walls have the advantages of not allowing turtles to see outside the enclosure which to some degree limits the amount of time the turtles pace the edges of the enclosures. Solid walls also provide partial shade. Rounded corners prevent or limit turtles and tortoises working the corners in an attempt to escape but this advantage is overstated and not a problem if the pen is well landscaped and of appropriate size. Wire enclosures, with the top 6 inches or so bent inward, work well. The wire should be supported every so often and secured to up right stakes. Trees and other items falling on the enclosure will collapse the wire inward leaving enough of an overhang that the turtles cannot escape. Even more than when inside, turtles and tortoises outside need shelters. Shelters protect them from extremes of weather, often become nesting sites, and are key to the animals feeling secure. For aquatic turtles submerged logs, broken flowerpots, cement blocks and aquatic vegetation all work. For terrestrial species simple boxes, buried pipes, and stumps all work well. Be creative and figure what works for your turtles and the location.
Management Planting/landscaping of enclosures not only makes them more esthetically pleasing but by picking the right plants this also provides hiding places, shelter from the elements, and food. Aquatic plants provide the additional advantage of cycling nutrients from the water, thereby acting as living biological filters. Combinations of submergent, emergent, and floating plants provide for maximum structure in the water column. A recent article in Terrapin Tails (Spring 2007, xxx) discusses the types of plants useful in landscaping enclosures. I prefer to use, where possible, plants native to the region of the turtles’ natural origin (Asian plants for Asian turtles, etc.). The turtles don’t care but it makes the enclosures more interesting, and for photography purposes the images become that much more authentic. Know your plants; for example, cactus would seem appropriate for any desert dwelling tortoise, are indigenous only to the New World and would not be appropriate in habitat designed for Middle East Testudo. Uneaten food should be removed on a regular basis. Aquatic pools can be built to drain by placing them at sites where ditches or down hill slopes will allow for draining or siphoning pools as needed. Filters and pumps which allow for constantly running water are good idea and in the long term save cleaning time. A separate water intake and drain should be provided for each pen. This will help prevent cross contamination from one enclosure to another as pathogens will not be flushed between pens. Feeding turtles modest amounts and then feeding again once all the food has been consumed is far better than having excess food rot or attract predators. Turtles can be fed in much the same way as they are when kept indoors. By feeding in a specific area turtles will learn to come to the food. This makes it easier to account for individuals and one can separately feed shy individuals or species off to the side. For both aquatic and terrestrial species it is best to distribute the food in a liner fashion as this allows all individuals access and prevents the bully turtles from getting a larger share of the food. For aquatic species I prefer food that floats and is not oily. Direct sun can bake terrestrial turtles and heat the water in ponds to unacceptable levels. Be sure to provide some shade and cover for the inhabitants of outdoor enclosures and keep in mind that the sun angles shift seasonally. Shade cloth works well as it can be taken down once the heat of summer is passed. Plants should be established within and outside the pen with shade in mind, and covered hides if well ventilated or insulated work well for non-aquatic species. Turtles of different sizes should be housed separately until they achieve adult size. This will allow for better growth, reduces scarring and tail amputations, and is less stressful for the smaller individuals. Small aquatic individuals should not be housed in deep water, even if they don’t drown they loose a lot of energy swimming to and from the surface and this slows their growth. By knowing your turtles’ behavior one has a reasonable chance of finding eggs. The pacing about of females, knowing the nesting seasons and times of egg laying, watching for trial nest holes one can get a rather good idea as to when and where eggs will be deposited. After rains are a good time to look for nest and for hatchlings. In most cases it is best to move eggs to the security of incubators for protection from predators, falling autumn temperatures, and excessive moisture or drying. However, not all eggs will be found and it is good to check out door enclosures carefully for hatchlings at appropriate times, particularly after early fall rains. Hatchlings for the most part do better if head started inside during their first winter. And for turtles from warm climates it may not be appropriate to leave young out during the winter until they have achieved some size.
Climate zones The US Department of Agriculture has identified various climatic zones (ten in the eastern US). These climate zones which are developed for agriculture, and are wildly use by people interested in nursery landscaping and flower beds, may likewise be a good guide for making educated guesses as to which turtles will be successful as out door captives at any particular location. The Tortoise Reserve is located in Zone 8. It has been my experience that species from adjacent zones to both the north and south do fine when kept outdoors throughout the year. A number of species from even greater distances also survive, and successfully breed here. For non North American species going on line and learning climatic conditions of the species’ native range is a much better idea than simply experimenting with leaving them outside and scoring survival vs. mortality. Sun exposure, shade, substrate, pond depths, and running water can all help to buffer local conditions. Keep in mind it’s the extremes, not the averages that kill things. Also you must remember the position of the sun shifts seasonally so turtles that should be sunning in early spring need to have pen exposures that catch good sun angles in April, but may need shading during the summer when the sun is more directly overhead. With good pre-planning you can have both. For those who can’t think beyond Wednesday there is always shade cloth. And you can cheat!! Many tortoises will learn to move into heated shelters during cool and cold weather, often emerging for a few hours on sunny, windless February days. Others, for whatever reason never seem to be able to learn this. They can be moved into shelters and locked in until appropriate temperatures return. There are recorded cases of red-footed tortoises coming out of shelters in three inches of snow, looking about and quickly returning to the protection of the shelter. Many sub-tropical and tropical aquatic species can also be kept outside in temperate locations throughout the year if the water is heated to 55 F or above. On sunny days these turtles will bask for hours to elevate body temperatures. The warm air rising off the water provides a heat dome just above the surface sufficient to prevent the turtles from breathing freezing air and getting respiratory problems. If you try to cheat Mother Nature watch your captives closely during the first season. Some of them will not have read this and they do not have the instincts to cope with your artificial environments. Species kept outside throughout the year without artificial heating at the Tortoise Reserve, White Lake, NC:
Inland from Charleston, South Carolina, I have a friend keeping flower back box turtles, yellow-headed box turtles, and keeled back box turtles outside throughout the year. Not discussed are species native to the region. I have been keeping local turtles in outdoor set up since the 1950s (Maryland, Florida, North Carolina) with considerable success. One just needs to make sure the outdoor housing is adequate for hibernation, and thermal regulation and provides adequate space and cover so that the turtles feel un- crowded and secure. There is no real formula for this other than more space is better for the turtles, but makes management of the turtles more difficult. The compromise will depend on the area available, the species considered, and the time of the person overseeing the turtles. For hibernation as long as the turtles (aquatic or terrestrial) can get below the depth of the frost line, terrestrial turtles (box, tortoises) and aquatic species which hibernate on land (chicken turtles, mud turtles) never seem to dig to frost line depths for hibernation but they should have this option. The only issue is to make sure you learn everything you can about a species and about the site for the enclosure (e.g., amount of sun exposure in May vs. August, drainage during major rain events, etc.) before you invest the time and money to construct an outdoor pen. I should add that most of my other sub adult turtles and tortoises are kept outside as the season will allow and I can see a marked difference in the behavior, growth, reproductive output, and the general over all long term health of turtles that get to spend a large percentage of their year outside. I think this success can be explained simply and easily…. Turtles outdoors are happy turtles. David S. Lee, © 2007 The Tortoise Reserve (Published in Terrapin Tails. October 2007. Pg. 20-24)
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