The Creation Wiki is made available by the NW Creation Network
Watch monthly live webcast - Like us on Facebook - Subscribe on YouTube

Cane toad

From CreationWiki, the encyclopedia of creation science
Jump to: navigation, search
Cane toad
Bufo marinus.jpg
Scientific Classification
Binomial Name

Rhinella marina

The Cane Toad is a species of toad known by the scientific name Rhinella marina, and also called the Giant Toad or Marine Toad. It is native to South America, and an invasive species that was introduced to other countries (including Australia) to control beetle populations. It is very adaptive and tough. The cane toad's most outstanding feature is its large poison producing parotid glands.

Body Design

Picture showing, on the right, the raised swelling behind the shoulder: the cane toad's Parotid gland

The cane toad is a large and stocky amphibian with the average adult male being 10-15 cm (4-6 in). The female is much larger and can grow up to 23 cm (9 in). They can exceed 4 pounds in weight.[2] A cane toad's skin is dry and bumpy. The color ranges from olive-browns, red-brown,grey and even yellowish colors. The underside is a pale whitish color.[3] The coloring and texture of a young cane toad is different than that of the adult. The juvenile has dark colored skin (sometimes with a little red coloring) and it lacks the bumpiness of the adult's. A cane toad also has a bony ridge that starts above its eye and extends down to its nose. The cane toad's back feet have webbing but the front toes don't have webbing.[4] The cane toad's most prominent feature is its Parotid glands which are located directly behind both of the toad's eyes. This gland oozes a poison (called Bufotoxin) when the toad is threatened. [2] The poison is a milky, whitish color and is designed to cover the toad's skin so that it mostly unavoidable to a predator that is about to eat it. The poison can be deadly to smaller animals, usually causing cardiac arrest.[5] The cane toad is poisonous during every life stage. The poison is so toxic, it can (and has) killed people who have ingested the eggs. The glands are designed to coat the skin in the toxin, however, they can still spray the offender.[3]

Life Cycle

Cane Toads reproducing eggs.

Cane toad's habitat is still or slow-flowing water.male cane toads are start looking for female cane toads when water temperature reaches 25ºC. When they are laying eggs, male cane toad grabs on female cane toad's armpit. Female cane toads may produce 8,000 to 35,000 eggs at once.[6]

The tadpoles of eggs that female cane toads has laid will hatch 48 to 72 hours after if the temperature is right for tadpoles to hatch. Anywhere from 17 to 180 days after hatching they will undergo metamorphosis.[7]

Juvenile cane toads are both diurnal and nocturnal. When female cane toads are wanting to breed they call aloud for male cane toads.[8]

When the toads metamorphose into subadulthood, they loose venom in their body that were protecting them when they were eggs, but they develop a parotoid glands which produce Bufotosin.[9]

Ecology

Habitat map of Cane Toads in the world

Cane toad's main habitat type is mostly subtropical forests with water areas, and they also live in a dry and humid area. They tend to go to water areas when they go through reproduction.[10] Cane toad eats almost anything they can swallow. They tend to eat pet foods in Australia which caused problems but mostly they eat beetles, honey bees, ants, winged termites, crickets and bugs are eaten when there are a lot of them. Marine snails, smaller toads and native frogs, small snakes, and small mammals can be eaten by Cane toads occasionally. Cane toads' tadpoles can also eat their fellow species' eggs. The Abiotic requirements they have is that they need the water temperature kept in 25-30ºC in order to have a healthy development. [11]

Adult cane toads can be seen in the grass area foraging or form aggregation and also they gather around where bright light is. Because insects are attracted to lights, so it's easy for them to consume the prey. Cane toads may consume arthropods and small vertebrates in Australia.[12] Adult cane toads are nocturnal. When the temperature gets too cold or too dry, cane toads make a shelter around moist crevices and hollows. Cane toads can survive in temperature 5ºC - 40ºC, it also can survive without 50% of their body water.[13]

Cane toads have predators such as meat ants, water beetles, saw shelled turtle, and Australian crows. When animals eat Cane toads they tend to have problems since Cane toads contain venom on them. The animals have found ways to avoid that problem from venom. For example Australian crows now eat Cane toads from underbelly so they don't reach the venom. [14]

Invasive Behavior

The cane toad was introduced into Australia to control two species of agricultural pests. The Greyback Cane Beetle and French's Cane Beetle larvae are capable of substantial damage to the roots of the sugarcane plant, either killing it affecting its growth. They were put in Queensland but didn't do the job they were intended to.[15] The cane toads had no natural predators in the areas they were released into and so adapted to their new environment and reproduced very quickly. They have become a major pest because of the damage they do to the native species (poisoning and killing many),carrying diseases, competing with the natives for food and even eating honeybees.[3] They are very adept in breeding and can reproduce in nearly any body of water from ponds to small streams. They can also survive in very harsh conditions including really cold and dry conditions (often by taking shelter in a little excavation).[16]

Pest Control

Several attempts have been made to control or eradicate the cane toad. Removing them by hand has had some successes but is unsustainable. People have tried to trap them too, but they also end up catching other native species.[17] Scientists are researching and trying to discover a biological agent or gene technology that would help control them. so far the scientists have not had any monumental successes. They are also seeing if they can find a way to stunt the growth of the cane toad tadpoles so that they cannot reproduce.[18] The cane toad does have natural predators especially the tadpoles and so if they were to spread to Washington, the government would have to be sure that there would be enough to control the population even a little. Also informing the public and organizing teams to remove them by hand or humanely kill them. Scientific research would be necessary.[19]

Cane toads were widespread in Australia and in one campaign each 100 people caught 900 cane toads. If cane toads were to be spread at Washington state there would be a huge disaster since natural amphibians will be killed by those cane toads. [20] The Australian government had long term strategy by spreading a virus toward the cane toads and stop them from spreading out. This projected ended in a bad result. People have tried many ways to control Cane toad but it didn't work that good. .[21] They also tried to have other predators for Cane toad and those animals can be listed as cat eyed snake, flagtail, killifish, catfish mostly. .[22]

Government were eager to control the cane toads. One of their solution was to attract the toads with sex pheromones and trap them, and get rid of cane toads with lung parasite to effect the cane toads and also many of Australian groups are catching cane toads with their hands.[23] Some scientists are predicting, if they remove 100 artificial waterbodies it will prevent cane toads from occupying western Australia.[24] Government has recommended keep the pets food and drinking water in side of the house and remove all the hiding spots that cane toads may fit in and build a 50cm high barrier to keep the cane toads out of their home.[25]

Video

Each cane toad carries enough venom to kill a small child. No wonder the locals aren't fans of this invasive species.

References

  1. Rhinella marina Wikispecies. Web. Updated October 4 2012. Unknown Author.
  2. 2.0 2.1 cane toad Animal Files. Web. Date of access 9 October 2013 Author unknown.
  3. 3.0 3.1 3.2 Cameron,Elizabeth . Animal Species:Cane Toad Australian Museum. Web. date of last update 11 September 2013.
  4. . Rhinella marina — Overview Cane Toad Encyclopedia of Life. Web. date of access 8 October 2013 author unknown.
  5. Leviticus, Jill. Cane Toad Toxin Pawnation. Web.Date of access 10 October 2013.
  6. Cameron, Elizabeth. cane toad Australian Museum. Web. Last updated September 11 2013.
  7. cane toad Department of environment and Primary industries. Web. Last updated May 20 2013.
  8. .cane toad Cane toad:facts, Characteristics, Habitat and more. Web. accessed 24 October 2013.
  9. Ecology, behavior and life history Encyclopedia of Life. Web. Accessed October 21 2013.
  10. Cane Toad: Facts, Characteristics, Habitat and More Animal Place. Web. accessed October 9 2013. unknown author.
  11. Cameron, Elizabeth. Animal Species: Cane Toad Australian Museum. Web. Last updated September 11 2013.
  12. .toad Cane toad. Web. accessed 24 October 2013.
  13. Cameron, Elizabeth. cane toad Australian Museum. Web. Last updated September 11 2013.
  14. Hanson, Jenna. Spiders keep cane toad numbers in check Australian geographic. Web. Published August 13 2012.
  15. . CSIRO cane toad research CSIRO. Web. last updated 14 October 2011 author unknown .
  16. .Cane toad - key threatening process listing NSW environment. Web. last updated 28 February 2011 author unknown .
  17. . CURRENT METHODS TO CONTROL CANE TOADS Cane Toads in Oz. Web. Date of Access 19 October 2013 author unknown.
  18. . Cane toad: a case study Biotechnology online. Web. Date of access 20 October 2013 author unknown.
  19. . Michell, Rhiannon Myth Busting Monday: Cane Toads Melbourne University. Web. Date of publication 18 April 2011.
  20. Cameron, Elizabeth. Animal Species: Cane Toad Australian Museum. Web. Last updated September 11 2013.
  21. . CSIRO cane toad research CSIRO. Web. last updated 14 October 2011 author unknown .
  22. Cane Toad: Facts, Characteristics, Habitat and More Animal Place. Web. accessed October 9 2013. Unknown author.
  23. stop the toad Stop the toad Keep WA cane toad free. Web. accessed 24 October 2013.
  24. Cane toad can be stopped Science Daily. Web. Published 12 December 2012.
  25. Keep pets safe from cane toads WikiHow. Web. Accessed 24 October 2013.