Amphibian & ReptileManagement

Dr. N. Matthew Ellinwood, D.V.M., Ph.D.

March 21, 2012

IOWA STATE UNIVERSITY

COLLEGE OF AGRICULTURE AND LIFE SCIENCES

• Domestic Animals?– Green iguana is kept as a food animal– Crocodile; $17 million impact (Louisiana) – Others?

• Companion animal management requires more closely replicating wild environments

• Habitat

• Food

• Regulation

General Considerations:Some relevant to Reptiles, Amphibians, and Fish

Feeding Amphibians

• Tadpoles– Carnivorous/herbivorous/omnivorous

• Adults– Visually oriented on prey (may require live

insects)– Carnivorous

• Insects (supplements)

• Fish

• Commercial diet (aquatic fish)

Vivarium

• soil or peat

• water – think fish– dechlorinate– filter– temperature

• shelter

Food

• Infusoria – babies– Purchased or maintained cultures

• Earthworms• Blood worms

– Both a fish and amphibian commercial food

• Drosophila• Crickets• Mice

Breeding Behavior and Development• Pseudocopulation

– Amplexus• Latin for embrace

• Fertilization can occur internally or externally– Internal fertilization

accomplished by females taking up spermatophores

– (Usually) water dependent development and with metamorphsis

Cites

• Convention on International Trade in Endangered Species of Wild Fauna and Flora

• http://www.cites.org/

• ~5000 animal species

• ~28,000 plant species

Threatened And Endangered• Sentinel species• Chytridiomycosis• 50% of Salamander and Newts at risk• 10% extinction of some classes

– Rhacophoridae "moss, bush, tree, or flying frogs"

Amphibians

• Smooth, moist, glandular skin– most species absorb water through skin– some species breath through skin

• Must spend part of life in water

• Metamorphosis

• Eggs adapted to water environment

• world – 6,260 species

• U. S. – 230 species

Evolutionary Concerns

• Derived from Coelocanth/lungfish type forebearer

• Developed in Devonian period– ~400 million years ago

• Top predators– Permian Triassic extinctions – 250 million years ago

Amphibians

• Frogs

• Toads

• Newts

• Salamanders

• Caecilians (clade Apoda)

Frogs

• Spend most or all of life in water

– green frog– Rana clamitans

FROGS

• American green tree frog – Hyla cinerea

Toads

• Develop in water

• Spend later life on land

American toad – Bufo americanus americanus

Newts• Spend (most of) life in water or marshy areas

• Regenerative abilities (see salamanders)

• Toxins: “She turned me into a Newt . . . . I got better”

red spotted newt – Eastern newt

Notophthalmus viridescens – easy to keep

Salamanders

• Approximately 320 species

• 2 to 70 inches in length

• Autotomy

• Limb regeneration etc (limbs, eyes, spinal cords, hearts, intestines)

Fire salamander – easy to keep

European and long lived

Axolotl – albino

Failure of metamorphosis

axolotl - gold

Axotltl

• Related to Tiger salamanders

• Research focus– Metamorphosis failure– Gilled and aquatic– Large embryo– Ease of production– Regenerative

• Named for lake under Mexico City

• Tiger salamander

• “terrestrial”

• Easy to keep

• Carriers of Chytrodiomycosis

Caecilians• Tropical

• Live underground

• 1 inch to 1.5 meters

• Seen in (aquarium) pet trade

• Sicilian eel

• Typhlonectes from South America (fully aquatic)

Fire Bellied Toad

• Small

• South Asia

• Toxins– Children

• Diurnal

• Can tame up

• 10-15 years

Poison Dart Frog

• Name

• South America– Rainforests

• Up to 1.5 inches

• Ants

• Diurnal

• 3-5 years

African Clawed Frogs• African

• Fully aquatic

• 6 inches

• 15 years

• Pet trade

• Research

• Carnivorous

• Good starter

Tree frogs• Americas, Asia, Europe• ~640 Spp

• Small

• Brightly colored

• Nocturnal– Special lights

– Special cycles

• Hyla cinerea– Mississippi Valley