Tomato Frog- MN



The Tomato Frog is an ectotherm, meaning that it is unable to control body temperature, and instead relies on the external environment. The frog has a vibrant, orange-red colour, with a pale underbelly. Females are generally larger and brighter than males, and some frogs have black spots on their throats.

Habitat
Frogs can exist in a wide range of environments, from deserts to snowy mountains. Frogs choose to live in these hostile environments because even though it can be tough, there is less competition for food and fewer predators.

The frogs are endemic to Madagascar, and are found to the northeast of the island around Antongil Bay, and to the south at Andevoranto. They are primarily terrestrial, inhabiting forests areas, and breed during rainy season in stagnant or very slow-moving water.

Thermoregulation of frogs
Although frogs are unable to fully control temperature by increasing metabolic rate, they have a range of physiological and behavioural adaptations to increase heat loss/absorption:

1. Changing colour: some frogs can change their colour to affect the amount of solar radiation they receive

2. Movement: basking in the sun to warm up or moving into shade to prevent overheating

3. Hibernation: frogs hide underground or in leaf litter when temperatures are very low. Some frogs convert glycogen to glucose in their liver to produce an 'antifreeze'. This means they can tolerate their body fluids freezing in the winter. They become stiff with no breathing or heart beat. Then thaw for the spring.

4. Water storage: Some frogs store water in their bladders. They reduce water evaporation by closing their eyes and tucking in their limbs or several frogs huddling together, thus minimising their surface area.

Water Control
Frogs don't often drink with their mouths, they absorb water through their skin. They have a 'seat pouch', an area on their bellies which is designed for water absorption. They absorb through capillary action from water or a moist surface.

Frogs also control water by burrowing and cocoons of shedded skin if in dry conditions.

Defence
It is thought that the brilliant colours of the tomato frog act as a warning to potential predators that these frogs are toxic; a white substance secreted from the skin acts as a glue to deter predators and can produce an allergic reaction in humans.

Threats and Conservation
Numbers of the tomato frog have been declining as a result of habitat degradation, pollution and over-collection for the pet trade. The tomato frog was rapidly included on Appendix I of the Convention on International Trade in Endangered Species (CITES) in response to this pressure. Research into captive breeding techniques for the tomato frog has been carried out. Madagascar is also attempting to educate local people about this attractive member of their natural heritage. Very little is known about the tomato frog and further research into its distribution, behaviour and potential threats is urgently needed before effective conservation measures can be put into place.