Photographer: David McClenaghan Affiliation: Commonwealth Scientific and Industrial Research Organization Source: www.bugwood.org Copyright: CC BY-NC 3.0
The cane toad (Rhinella marina) also called the giant toad is the largest species within the family Bufonidae. The cane toad has an average weight of 4lbs and can be 4-9 inches wide. The cane toad has dry, warty skin, and camouflages well with its surroundings to evade predators. Parotid glands are located behind the ears giving the head a swollen look, which are used to deter predators by secreting toxins.
The cane toad is a threat to native toad species because it is aggressive and known to out-compete for resources. The cane toad is also toxic to domestic pets and predators hindering natural eradication of established populations. The toxin produced is harmful to all species and causes irritation and burning of the skin.
Cane toads are very adaptable to finding places for breeding and laying eggs with the only requirement of sufficient standing water for tad pole growth. Commonly used areas are shallow pools or ditch ponds where a clutch size of 8,000 to 17,000 eggs will be laid. Eggs and larvae are considered poisonous and are capable of displacing native toad species. Cane toad larvae are also tolerant to high temperatures, allowing for use of shallow pools of water.
The cane toad was introduced to the United States in 1955 as a biological pest control agent in sugar cane fields. However, it escaped and became established outside sugar cane fields.
U.S. Habitat: In native habitats, the cane toad is found in subtropical forests near fresh water sources. In the United States cane toads can be found in a variety of habitats with sufficient water and cover for hiding such as cane fields, savanna, open forests, well watered yards, and gardens. In man-made areas they can often be found under piles of wood, near roads, grazing land, and suburban parks.
U.S. Present: FL, HI, LA, TX
Texas: Southern Texas along the border of Mexico from Brownsville to the North of Laredo.
Management efforts of the Cane Toad in Australia usually are by physical means; and depends on volunteer groups helping. It is a similar case in Florida; but also local universities provide networks for citizens to report sightings. Populations of this toad in Louisiana and Texas have not reached extreme proportions such as overseas. In Texas, the drought has prevented the Cane Toad for further expanding upwards. However, with wetter years this could change; but there are groups that are prepared for physical management if the need arises.
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