Slide-out tanks in racks can provide economical and efficient housing enclosures for amphibians that have limited climbing abilities. It is easy to remove the tanks without fear of breakage for cleaning or inspection. 

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... aquariums and accessories held in commercial racks can provide the requirements listed above. Personnel can modify plastic containers and glass aquariums for use as enclosures. Plastic pet tanks are especially valuable because they stack in a small volume, are relatively robust, and are insect proof (see Figure 2). Other materials such as fiber- glass and concrete afford the possibility for fabricating large tanks, troughs, and flyways. To avoid toxicity from metals, it is important to construct water supply systems from high- density polyethylene, polypropylene, or nylon. However, because fiberglass, concrete, some plastics, and other materials can leach harmful compounds, it is essential to as- certain their toxicity, to wash the material appropriately, and, if necessary, to allow the compounds to “ weather. ” The minimum requirements for lids are that they (1) prevent the escape of amphibians and their live feed, (2) provide adequate ventilation for both respiration and the escape of heat, and (3) allow for the passage of ultraviolet (UV 2 ) light. The escape of amphibians can result in death, and the escape of both amphibians and their live feed can result in the spread of pathogens. In humidified rooms, ventilation rates in tanks are balanced between the maintenance of humidity and the removal of excess heat. Humidification of the whole room enables the use of open mesh lids to maximize ventilation (see Figure 1). The most valuable resources for decisions about the size of enclosures are the experiences of other individuals and in- stitutions. As a specific example, in the case of the medium- sized adult Wyoming toad ( B. baxteri ), Browne et al. (2006b) kept four individuals in 45-L glass aquariums with a 25-cm-thick sponge mat and a cork bark slab for shelter or basking. Standard fluorescent lights in the aquarium and lights set on a timer simulated natural daylight hours. A water tray (10 cm diameter × 2 cm depth) was placed at one end. The tanks and sponge mats were cleaned daily. Each aquarium housed four female or six male toads (Figure 4). Most commercial reptile racks are suitable for toads and ground frogs that are poor climbers. However, many frogs, especially tree frogs, and burrowing amphibians including many salamanders and caecilians need tight-fitting covers to prevent their escape. Although a problem with all racks is that disease easily spreads between enclosures, it is possible to minimize this problem by using partly independent drain- age systems for each tank and by wearing gloves and using other barrier techniques during servicing (Gutleb et al. 2001). It is customary to program lighting to simulate natural light cycles. As the latitudes move from the equator, the seasonal differences in the daily cycle become more pronounced. Tropical amphibians generally thrive with 12 hours of light- ing. Substrate temperature gradients produced by heating elements beneath the cage floor may be more effective than photothermal gradients, especially for nocturnal or secretive amphibians. Many adult and larval amphibians bask in the sun or use temperature gradients to regulate body temperatures above ambient levels to increase growth rates of di- gestion and development and to fight infection (Browne and Edwards 2003; Feder and Burggren 1992; Maniero and Carey 1997; Ultsch et al. 1999). Basking amphibians have mechanisms to prevent water loss through the skin and tend to be more tolerant of low humidity (Withers et al. 1984). There is surprisingly little information on the effect of different combinations of visual and UV light on amphibian health. Middle-wavelength ultraviolet light (UVB 2 ) from 285 to 320 nm penetrates the skin and enables the synthesis of vitamin D 3 in many vertebrates (Holick 1989), with peak conversion at 297 nm (MacLaughlin et al. 1982). Some species of amphibians may require UVB light for calcium metabolism, normal behavior, and reproduction. The requirement of UVB for cryptic nocturnal rainforest species is not known. However, Carmen et al. (2000) have shown that nocturnal geckos are more sensitive to UVB and convert D 3 with limited exposure at dusk/dawn. In addition, many cryptic nocturnal frogs hide in plain sight where they would receive substantial UVB exposure during daylight hours during periods of inactivity. Consequently, it is important to provide UVB to all captive amphibians by exposing the animals to one of the following: to natural sunlight, through specialized skylights manufactured from clear polymers that are transparent to UVB (e.g., Polycast Solacryl ® ); or to artificial lighting sources that produce UVB. A wide variety of artificial lighting systems are available for the provision of UVB for captive husbandry of amphibians and reptiles. It is customary to classify these systems as (1) fluorescent, (2) mercury vapor, and (3) halogen, on the basis of the lighting technology used to generate UVB. The following brief summaries of these systems include the pros and cons of ...

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... amphibian rooms for each popula- tion. Other spaces and services include live feed rooms, quarantine stations, isolation rooms, laboratory space, tech- nical support systems, reliable energy and water supplies, high-quality feed, and security. Good husbandry techniques must include reliable and species-specific management by trained staff members who receive support from the administration. It is possible to improve husbandry techniques for many species by sharing knowledge through common information systems. Overall, good facility design corre- sponds to the efficient use of space, personnel, energy, materials, and other resources. Key Words: amphibian; captive breeding; facilities; husbandry; quarantine; research; UVB; water quality acility layout depends on the number and variety of species to be housed, their environmental requirements, the number and distribution of enclosures, the regional climate, and the purpose of the facility. The environmental range of species and their climatic requirements determine the number and design of temperature-controlled rooms. The distribution of amphibians between enclosures determines the number of enclosures and racks. Within this system, personnel isolate amphibians by single species or species assemblage (an amphibian faunal group that naturally occurs in the range country), optimum temperatures, life stage, or other factors. The regional climate affects facility layout, and climate extremes especially limit the dis- persal of structures within the facility. For information about amphibians that is beyond the scope of this article we recommend that readers consult the following literature: for General Husbandry : Gresens (2004), Halliday (1999), Mattison (1987), Nace et al. (1974), O’Reilly (1996), Pough (1992), Reed (2005), Schimdt and Henkel (2004), Schultz and Douglas (2003), Wake (1994), Wright and Whitaker (2001), and Zippel (2005); Biology : Duellman and Trueb (1994), Feder and Burggren (1992), Frazer (1976), Hofrichter (2000), Stebbins and Cohen (1995); and Larval Biology and Larval Rearing : Browne et al. (2003), and McDiarmid and Altig (1999). Quarantine is critically important to prevent the spread of pathogens from surrounding environments into the facility, within the facility, and from the facility to surrounding environments. When investigators intend to eventually release amphibians, the amphibians’ isolation from other populations in the facility is of utmost importance. It is also essential to keep only a single species or species assemblage per room. The published and web literature in aquaculture is re- plete with information on the safety of materials and the design of enclosures, water systems, and other physical components of systems for the maintenance of aquatic and amphibious animals. Exemplary publications include Barnett et al. (2001), Lucas and Southgate (2004), Nace et al. (1974), Pough (1992), Pough (1989), and Wheaton (1977). In moderate climates, facilities that house local species may have a minimum of insulation. It may be desirable in those climates to have an open design with different rooms placed in a cluster of different buildings. The advantage of clusters of structures is that quarantine is more assured for specific amphibian rooms. By contrast, in extreme climates including northern continental climates, it is desirable to have a more centralized facility. However, it is still necessary for the amphibian facility to accommodate full quarantine, including the water supply, for pedestrian traffic and for materials including substrates for enclosures. Within the facility, it is necessary to be able to quarantine the animals between enclosures, arrays, and amphibian rooms. Intuitively, the best captive husbandry of amphibians would provide conditions that simulate their natural habitat. Some small species with complicated behaviors and reproductive requirements (e.g., dendrobatids and mantellas) thrive and reproduce in “ natural ” systems (Schmidt and Henkel 2004; Zimmerman 1986). Nevertheless, the first choice for the large-scale captive rearing of amenable amphibians is simple, easy-to-maintain, medium- to high- density systems. Descriptions of medium- to high-density aquarium systems for laboratory models include those for Xenopus spp. (Reed 2005; Schultz and Douglas 2003) and Ambystoma mexicanum (Gresens 2004). Simple medium- density terrestrial systems have been developed for the southern leopard frog ( Rana sphenocephala ) 1 (Nace et al. 1974; Pough 1989), Fowler ’ s toad ( Bufo fowleri ) (Browne et al. 2006a), the cane toad ( Bufo marinus ) (Browne et al. 1998), and the endangered Wyoming toad ( Bufo baxteri ) (Browne et al. 2006b). Medium-density systems have also been developed for the commercial production of amphibians for pets or display (Mattison 1987; Zimmerman 1986). High-density systems are used for commercial ranid species and similar systems should be suitable for the rearing of many other pond species (Figure 1). The number of threatened amphibians in captive breeding programs is increasing, and research estimates this number will finally include hundreds of diverse species with a wide range of physiological requirements (Hofrichter 2000; Young et al. 2004; Zippel 2005). The maintenance and reproduction of these amphibians with diverse natural histo- ries and from diverse habitats and climates has already proved challenging. These husbandry challenges include the need to meet specific physiological requirements for adults and larvae (Halliday 1999; Stebbins and Cohen 1995), and to house large numbers of adults and larvae needed to produce the numbers of amphibians required for rehabilitation projects (Browne et al. 2003; Culley 1992; Zippel 2005). It is possible to meet the associated challenges in facility design and services by using new technologies. For instance, the control of temperature is a major factor in the growth and sexual maturation of amphibians (Brenner 1966; Horse- man et al. 1978; Pancharatna and Patil 1997). With the provision of sophisticated technologies for lighting and heating, many temperate species will bask to select their optimum temperature and to satisfy their ultraviolet (UV 2 ) requirement (see Artificial Lighting, Heating, and Humidity below). Reproduction technologies, which also require in- novative facility design, include the production of large numbers of larvae by high-density larval rearing and the provision of cryobiology systems (Reed 2005; Browne et al. 1998, 2003; Schultz and Douglas 2003). We recommend considering a modular system of modified shipping containers, which can be adapted to serve as independent units for the maintenance of single species or species groups (ARC 2007). These systems require only external power, water, and waste disposal systems to function. They are well insulated and can efficiently keep amphibians cooler or warmer than the ambient temperature of the surrounding environment. Within these systems, most operations include flushable tanks and automated temperature and lighting. For the maximum storage of tanks, shelves feature a “ compactus ” design that is similar to those used in archives. To minimize lighting costs, it is advisable to provide windows in all administration and laboratory spaces if possible. We recommend using UV-penetrable glass in the windows of amphibian holding rooms. The need to control photoperiods in these holding rooms limits the use of windows for lighting. However, windows and skylights can still provide natural light during the light photoperiod. Atriums can provide light to the interior of buildings as well as areas for visitors. For energy efficiency, the size of windows, skylights, and atriums should be minimal to provide adequate lighting and should be double glazed for insulation. It is advisable to attach external shutters or awnings to both windows and skylights to control light and heat. Fixed shutters can both increase light in winter and prevent excessive heat during summer. Alternatively, adjustable shutters operated automatically or manually can provide even greater control of light and heat (see the Wikipedia description of passive solar []). It is important to find an economical balance between the need for natural ventilation to provide fresh air and the consequent energy costs of heating or cooling. The optimal turnover of air in the facility will depend on the temperatures and humidity of external air. A high turnover of dry air can lower humidity enough to dehydrate amphibians, and low turnover can cause humidity that is high enough to promote the growth of mold. In moderate climates, it is possible to ventilate facilities that house local amphibian species naturally and to climate control only the staff areas. Because racks or tanks can be heavy, it is necessary to ensure that the floors can support these weights. Floors, walls, and the ceilings of amphibian holding rooms should be waterproof to enable washing or steam cleaning. All construction materials must be able to tolerate high humidity (e.g., drywall [plasterboard] and cellulose drop ceiling panels are inappropriate). Many chemicals used in furniture and coatings may be toxic to amphibians (Sciencesoftware 2007). Floors can be concrete or covered with a waterproof covering. Even in small facilities, it is necessary to desig- nate at least one room as a wet area where personnel can wash and sanitize equipment including tanks and tubs. It is important to equip wet areas with floor drains that have mesh coverings of sufficient size to prevent the escape of amphibians and the entrance of pests. It is essential to frequently disinfect these areas to prevent disease transmission from occurring within the facility through open floor drains. To prevent the escape of waterborne pathogens, liq- uid waste should be drained into a holding tank for disinfection before discharge into a municipal system. Facilities should sterilize their ...