REPTILES

Name: Slider (Red-eared/Yellow-bellied)  

(Trachemys scripta)

Description: Aquatic sliders are really basking turtles. In spring or fall, or any time the weather is mild and the sun is out, individuals or groups of slider turtles may rest on logs or rocks. They are brown or olive green, usually with a prominent patch of yellow or red (depending on the sub-species) on the side of the head, with a rounded lower-jaw. The yellow underside of the turtle's shell sometimes is marked with round dusky smudges.

Natural Habitat: Slider turtles are abundant in the ponds and streams of the southeastern United States. They can be found in bays, sloughs, sinkholes, lakes, swamps, rivers,  and ponds. In Arizona, they are considered an invasive species, and can provide competition to our precious native turtles.

Movement: Sliders are a semi-aquatic species, and except for terrestrial excursions, the animals remain in water where submerged and floating vegetation is abundant. They move on land to lay their eggs in a terrestrial nest. The animals also move on land to and from hibernation sites or alternate feeding areas and to leave unsuitable aquatic habitats.

The periods of greatest overland and aquatic movement usually are in spring and fall. In the winter, slider turtles become dormant, but the animals sometimes are active on sunny winter days. Summer is a period of reduced basking activity, compared to spring and fall.

Diet: Sliders prefer a diet of insects, dead fish, tadpoles and other meat items. Slider turtles can subsist on a vegetative diet, although their growth rates may be significantly lower than that of turtles whose diet is mostly meat. Plant materials in the slider turtle's diet can include algae, leaves, stems, roots, fruits and seeds. They feed on larger invertebrates, such as water insects, and vertebrates such as small fish, tadpoles and frogs. Slider turtles are not normally able to capture healthy fish.  

Name: Western Painted Turtle

(Chrysemys picta belli)  

Description: The painted turtle is another species of aquatic turtle found throughout North America. Most of the information on sliders can be applied to painted turtles as well.  

Name: Box Turtle

(Genus:Terrapene)  

Description: The box turtle is usually under half a foot long and have a hand painted look about them.  Conspicuous yellow dashes cover its dark brown or black carapace and radiate from the center of each shell segment down the sides, and its plastron is a mix of faded yellow and black patterns. The foreleg scales assist box turtles in digging and movement. The males are equipped with a sharply curved first claw on their hind feet - used to grasp females during breeding.  Jaws are often lined with pale yellow, the upper jaw being slightly notched at the front edge.

Natural Habitat: Box turtles are not native in Arizona, but in the Northwest, Midwest, and eastern states, box turtles are usually associated with sandy soils, dry prairies, and oak savannahs. They prefer southern and western exposures where temperatures are higher and soils are drier. This species requires deep sandy soil to burrow into for hibernation in the winter.  

Name: Sonoran Mud Turtle (“stinkpots”, “stinkjims”)

(Kinosternon sonoriense)

Habitat: Sonoran mud turtles are found in springs, creeks, ponds and waterholes of intermittent streams. Our only specimen was found in the backyard of a homeowner, being chewed on by his dog. The shell will be forever damaged, but the turtle is okay and enjoying our constructed wetland exhibit.

Range: Sonoran mud turtles are found in the southwest deserts of the United States, and are a candidate for the endangered species list.

Biology: When handled, this turtle gives off a musky odor, hence they are sometimes called "stinkpots". The odor glands are located on each side of the body where the skin meets the underside of the shell.

Reproduction: The female Sonoran mud turtle will lay a clutch of 2-9 eggs from May to September and bury them in the soil.

Diet: This species eats a variety of food including insects, crustaceans, snails, fish, frogs and some plant materials.

Name: Snapping Turtle

(Chelydrae Serpentia)

Natural Habitat: Commonly found in fresh water habitats such as lakes, rivers, and marshes. They prefer quiet and slow-moving waters with a soft muddy bottom.  

Diet: The snapping turtle is omnivorous, therefore, they eat both plants and animals. The animals they eat include: insects, fiddler crabs, shrimp, water mites, clams, snails, earth worms, leeches and water sponges - basically anything they can capture. Since the snapper has such big jaws, it can even capture larger prey, such as fish and snakes. The plants they eat include all different types of algae and aquatic plants.

Interesting Facts: Since the snapper is so big (it can grow to be half a meter long and 150 pounds!) it is a top predator in the aquatic systems. It’s large claws and spiny tail are enough to scare the bravest of people!

Name: American Alligator

(Alligator mississippiensis)

Natural Habitat: Capable of reaching lengths of up to 12 feet, the American Alligator is the largest reptile in North America and one of the most famed and feared residents of the Southeast. Though their populations were once reduced by illegal hunting, they are commonly seen during the day basking along river banks.

Agricultural Production: Alligators are an important part of agriculture/aquaculture. In the Southest, they are farmed for their expensive hides and meat. Some places even make ‘gator jerky’! The alligators at the Maricopa Agricultural Center will be used for scientific research and educating the public about this unique area of agriculture. Hopefully, alligators will arrive at MAC in the spring of 2003.  

SALAMANDERS  

Name: Salamander (mudpuppies, newts, “fish bait”)

(Order: Caudata)

Description: Salamanders are a diverse group of amphibians.  In Arizona and throughout the world, they can be found in both aquatic and terrestrial habitats, though water is essential for survival.  Most salamanders are nocturnal and can be found under rocks and fallen trees. They are commonly found in wetlands, and used in the fishing industry for bait.  

FISH

Name: Catfish (Blue, Channel, White, Bullhead and Bigmouth)

(Family: Ictaluridae)

General Description: From the family Ictaluridae this is one of the most popular sport fish for its fighting nature and excellent tasting flesh.  Catfish like nutrient rich water, are bottom feeders and have no scales.  Characteristic of the species is 1-4 pairs of barbels which resemble whiskers, hence the name catfish.  All catfish require good oxygen levels.  The channel catfish are the most popular species in the Southwest.  Bullheads do well in large ponds in this region but require intensive management practices and are therefore not recommended for stocking.

Size Range: Regularly to 5 lbs. with AZ state record at 31 lbs. 10 oz.

Temperature Range & Water Quality Standards: Optimal temperature range is 70-86°F.  Oxygen sensitive requiring 5ppm dissolved oxygen.  Nutrient rich water preferred and will tolerate turbid or muddy water. pH of 6-9.5 is best.

Spawning Habits & Conditions: Spawning occurs in the temperature range of 70-75°F.  A good brood fish is over 2 lbs. and 2-3 years old; however, they become sexually active at about 3/4 lb.  Catfish lay 3-20,000 eggs averaging 3,000 eggs per pound of body weight depending on the size of the female.  The eggs hatch in 5-10 days.  Channel catfish will not spawn reliably without the addition of a spawning structure in the form of tubes or enclosures.

Diet: Respond well to artificial feeding and are omnivorous consuming animal and plant material.  Large fish eat minnows.

Stocking Rates & Suggestions: 12 brood fish per acre.  50-100 of 2-4 inch fingerlings per acre.  Proper stocking of catfish with the addition of some forage fish normally produces good fishing within 1-2 years.  

Name: Tilapia (African Cichlids)

(Genus:Oreochromis)

General Description: Tilapia are a robust, tropical fish originally imported from east Africa.  They do best in warm water and have minimal respiratory demands making them easy to transport.  Tilapia reproduce rapidly and will tend to overpopulate.  Currently tilapia are becoming a favored product of food fish farmers and consumers enjoy their flavor.  These fish are also considered a good forage fish for bass and catfish populations due to their rapid reproduction rate.  In the Southwest it is usually necessary to restock tilapia each year due to winter water temperatures that drop below their survival limits.  The cost to restock still undercuts the cost of chemical treatments producing similar results.  Tilapia are an excellent tool in controlling filamentous and chemically resistant nuisance algae such as lyngbya.

Size Range: 3-8 inches up to 3 lbs.

Temperature Range & Water Quality Standards: Lowest 54-56°F, Optimal 70°F, Upper range 86-90°F.

Spawning Habits & Conditions: Tilapia reach adulthood in the second 6 months of life.  Tilapia will spawn at approximately 6 inches in size.  Tilapia require 68-70°F to spawn and will spawn repeatedly at 4-5 week intervals in warm water.

The male constructs a nest in shallow water digging a hole in the lake bottom.  The size of the nest is dependent on the size of the fish and should be considered a factor when stocking in lakes constructed with liners.  Nesting holes up to 3 feet deep have been noted.  Eggs are laid and fertilized in the nest and then watched or held in the males mouth until hatched, hence some species are called mouth-brooders.

Hatches of several hundred to several thousand offspring occur in six days.  The T. zilli spawn at a greater rate than the T. mozambique which spawn a higher percentage of male offspring.

Diet: Each species of Tilapia shows a marked preference for certain foods.  Some species feed only on microorganisms while others also feed on plant materials.  Most of our interest has been with mixed gene pools which, due to their voracious appetite, will control chemically resistant blue green algae's, i.e. lyngbya, which are a common nuisance in the Southwest.  1-3 inch Tilapia will tend to consume more nuisance algae than larger fish.  Most Tilapia will also consume insect larvae, crustaceans and decaying organic material.

Stocking Rates & Suggestions: 300-500 brood Tilapia per acre.  When stocking with bass allow tilapia to become established prior to introduction of bass.  

Name: Koi  (Nishikigoi)

(Cyprinus carpio)

General Description: Striking patterns and delicate coloration typify this carp whose popularity is rapidly increasing for spectators and enthusiasts alike.  Although often associated with Japan, Koi originated in eastern Asia and Chine some 2,500 year ago.  It was not until the 20th century that Koi keeping as a hobby began to flourish.  Koi have been breed to produce over one hundred varieties of color, pattern and luster or scalation of a particular fish and are characterized by 2 pairs of barbels.  Dedicated enthusiasts prefer to choose each fish for its particular qualities.

Size Range: Commonly 6-14 inches.  Koi show classifications reach 32 inches and Koi exceeding 100 pounds have been recorded.

Temperature Range & Water Quality Standards: A fish comfortable in a wide temperature range of 36-85°F.  Koi prefer pH in the range of 7-8 with minimum oxygen levels of 6 ppm.  Maintaining minimum ammonia and nitrite levels are important for healthy Koi.

Spawning Habits & Conditions: In late spring and early summer Koi of 15 inches may spawn.  Spawning is frantic and usually occurs when warm days and cool nights are present.  Kou will eat their own eggs; therefore, all spawning ropes should be removed when spawning is completed.

Diet: Koi consume a wide variety of foods.  High quality, balanced foods containing 35% protein, carbohydrates, vitamins and minerals with minimal fats and stabilized vitamin C are characteristic of a balanced diet that produces healthy fish with strong growth rates.  Koi also like earthworms, snails, lettuce, cockles, prawns, tadpoles, frogs and brown bread. Metabolism changes with the season and feeding should be appropriate.  Overfeeding Koi in the winter can be detrimental to health and water quality.  Ask our biologists for specific feeding suggestions.

Stocking Rates & Suggestions: Stocking rates are determined primarily by the size of the pond and capacity of the biofiltration system to breakdown wastes and organics.  Stocking should be assessed for each pond.  

Name: White Amur (grass carp)

(Ctenopharyngodon idella)

Natural Habitat: White Amur (Grass carp) is a natural inhabitant of the flatland rivers of China and the middle and lower reaches of river Amur in the USSR and the fish has been introduced into many other countries in recent times. In some of the countries the main purpose of its introduction, in addition to culture, is biological aquatic weed control in natural waterways, lakes and man-made lakes.

Physiology: Grass carp, like other cyprinids, has a toothless mouth but has specialized pharyngeal teeth for rasping aquatic vegetation. These teeth occur in two rows, the upper consisting of two small teeth on either side and the lower of strong comb or file-like teeth comprising four on the right and five on the left pharyngeal bone. In fishes of total length 30 cm and below, the lower pharyngeal teeth have a serrated cutting surface, while in larger fish the teeth are thicker and have double flattened serrated cutting and rasping surfaces. These patterns of teeth structure are associated with the change in the feeding habit. Large fishes are able to masticate the leaves of tough land plants such as fibrous grasses. Digestion in the grass carp is said to be incomplete and about half the food material ingested is excreted as feces, which, it is believed, can support directly or indirectly a large biomass of other species of fish.

Diet: The natural food of grass carp fry about 7-9 mm long is protozoa, rotifers and nauplii to which diet Cladocera and copepods are added as they grow to about 12 mm length. Cladocera, copepods and benthic algae form the diet of fry 13-17 mm long to which organic detritus is added up to a length of about 23 mm. As the fry grow to about 30 mm length, phytoplankton and minute algae become conspicuous additions to the diet. For fish above 30 mm, the natural diet is virtually exclusively macrovegetation, tender aquatic weeds like Wolffia initially and a wide variety of other aquatic macrovegetation and even softer land plants as the fish grows. Among the macrovegetation, the preferred weeds in the different regions of the world are: Wolffia, Lemna, Spirodela, Hydrilla, Najas, Ceratophyllum, Chara, Potamogeton, Vallisneria and Myriophyllum.

Interesting Facts: The fry and larger fish take to substances like cereal brans, oilcakes, silkworm pupae, kitchen refuse, night soil and dung which are often given as supplementary food.  In natural waters, grass carp attains a length of 15 to 30 cm weighing 225 g to 650 g at the end of first year; a length of 60 cm and a weight of 1.8 to 2.3 kg at the end of second year. After four years, the weight may be 4.5 kg.  In the Yangtze and West River systems, fish weighing 9 to 13 kg are common and fish weighing more than 20 kg have been caught.

Under culture conditions, growth is a function of stocking rate and feeds given and their conversion rate, competition with other fish co-stocked with grass carp and environmental conditions. Hickling (1967), comparing the daily growth of grass carp in different countries, observed it to be 2.8 g in Siberia, 3.3 in Turkmenia and south China, 6.6 to 9.8 in Israel, 4.7 in India and 8.3 to 10 in Malacca. ln Chinese ponds, grass carp attains a weight of 225 to 680 g in the first year, 1,200 to 2,300 g in second, 2,700 g in third and 3,800 g in the fourth year.

Age at which grass carp attains maturity varies greatly with climate and environ­mental factors, especially temperature. In China, the approximate age at maturity of grass carp is 15,000 degree (°C)-days, counting only those days when water temperature exceeds 15°C.

Reproduction: Lin (1935) reported that in China a female grass carp weighing 7 kg had 100,000 ova. Inaba et al. (1957) estimated 485,000 ova in a grass carp weighing 7.1 kg. The ovarian eggs of grass carp have a diameter varying between 1.19 and 1.37 cm. A fully swollen water-hardened spawned egg of grass carp has a volume of approximately 0.055 ml. A grass carp hatchling after absorption of the yolk sac weighs approximately 0.0022 g. The fish breeds during monsoon months in the flowing waters of its natural habitat, the rivers, but does not spawn naturally in the static waters of ponds and tanks.