Editing Cane toad (section)

==Ecology, behaviour and life history==
[[File:CSIRO ScienceImage 1842 Cane Toad Spawn.jpg|thumb|Cane toad [[Spawn (biology)|spawn]]]]
The common name "marine toad" and the scientific name ''Rhinella marina'' suggest a link to [[marine biology|marine life]],<ref name="Tyler1989p116">{{Harvnb|Tyler|1989|page=116}}</ref> but cane toads do not live in the sea. However, laboratory experiments suggest that [[tadpoles]] can tolerate salt concentrations equivalent to 15% of [[seawater]] (~5.4‰),<ref name="Ely1944p256">{{Harvnb|Ely|1944|page=256}}</ref> and recent field observations found living tadpoles and toadlets at salinities of 27.5‰ on [[Coiba Island]], [[Panama]].<ref>{{cite journal | last1 = De León | first1 = L.F. | last2 = Castillo | first2 = A. | year = 2015 | title = ''Rhinella marina'' (Cane Toad). Salinity Tolerance | journal = Herpetological Review | volume = 46 | issue = 2| pages = 237–238 }}</ref>  The cane toad inhabits open grassland and woodland, and has displayed a "distinct preference" for areas modified by humans, such as gardens and drainage ditches.<ref name="Lever2001p3">{{Harvnb|Lever|2001|page=3}}</ref> In their native habitats, the toads can be found in subtropical forests,<ref name="issgBufoMarinus" /> although dense foliage tends to limit their dispersal.<ref name="BarkerGriggTyler1995p380">{{harvnb|Barker|Grigg|Tyler|1995|p=380}}</ref>

The cane toad begins life as an egg, which is laid as part of long strings of jelly in water. A female lays 8,000–25,000 eggs at once and the strings can stretch up to {{convert|20|m|ft|abbr=on}} in length.<ref name="Tyler1989p116" /> The black eggs are covered by a membrane and their diameter is about {{convert|1.7|-|2.0|mm|in|abbr=on}}.<ref name="Tyler1989p116" /> The rate at which an egg grows into a tadpole increases with temperature. Tadpoles typically hatch within 48&nbsp;hours, but the period can vary from 14&nbsp;hours to almost a week.<ref name="Tyler1989p116" /> This process usually involves thousands of tadpoles—which are small, black, and have short tails—forming into groups. Between 12 and 60&nbsp;days are needed for the tadpoles to develop into juveniles, with four weeks being typical.<ref name="Tyler1989p116" /> Similarly to their adult counterparts, eggs and tadpoles are toxic to many animals.<ref name="Robinson1998" />

When they emerge, toadlets typically are about {{convert|10|–|11|mm|in|abbr=on}} in length, and grow rapidly. While the rate of growth varies by region, time of year, and sex, an average initial growth rate of {{convert|0.647|mm|in|abbr=on}} per day is seen, followed by an average rate of {{convert|0.373|mm|in|abbr=on}} per day. Growth typically slows once the toads reach sexual maturity.<ref name="ZugZug1979pp14-15">{{Harvnb|Zug|Zug|1979|pages=14–15}}</ref> This rapid growth is important for their survival; in the period between metamorphosis and subadulthood, the young toads lose the toxicity that protected them as eggs and tadpoles, but have yet to fully develop the parotoid glands that produce [[bufotoxin]].<ref name="ZugZug1979p15">{{Harvnb|Zug|Zug|1979|page=15}}</ref> Only an estimated 0.5% of cane toads reach adulthood, in part because they lack this key defense<ref name="Tyler1989p117" /><ref name="Anstis2002p274">{{Harvnb|Anstis|2002|page=274}}</ref>—but also due to tadpole cannibalism. Although cannibalism does occur in the native population in South America, the [[rapid evolution]] occurring in the unnaturally large population in Australia has produced tadpoles 30x more likely to be ''interested'' in cannibalising their siblings, and 2.6x more likely to actually ''do so''. They have also evolved to shorten their tadpole phase in response to the presence of older tadpoles. These changes are likely genetic, although no genetic basis has been determined.<ref name="Kozlov-2021">{{cite journal | last=Kozlov | first=Max | title=Australia's cane toads evolved as cannibals with frightening speed | journal=[[Nature (journal)|Nature]] | publisher=[[Nature Portfolio]] | volume=597 | issue=7874 | date=2021-08-25 | issn=0028-0836 | doi=10.1038/d41586-021-02317-9 | pages=19–20| pmid=34433984 | bibcode=2021Natur.597...19K | s2cid=237305658 }}</ref>

As with rates of growth, the point at which the toads become sexually mature varies across different regions. In New Guinea, sexual maturity is reached by female toads with a snout–vent length between {{convert|70|and|80|mm|in|abbr=on}}, while toads in [[Panama]] achieve maturity when they are between {{convert|90|and|100|mm|in|abbr=on}} in length.<ref name="ZugZug1979p8">{{Harvnb|Zug|Zug|1979|page=8}}</ref> In tropical regions, such as their native habitats, breeding occurs throughout the year, but in subtropical areas, breeding occurs only during warmer periods that coincide with the onset of the [[wet season]].<ref name="Lever2001p6">{{Harvnb|Lever|2001|page=6}}</ref>

The cane toad is estimated to have a critical thermal maximum of {{convert|40|-|42|C|F}} and a minimum of around {{convert|10|-|15|C|F}}.<ref name="Tyler1989p118">{{Harvnb|Tyler|1989|page=118}}</ref> The ranges can change due to adaptation to the local environment.<ref name="Tyler1989p119">{{Harvnb|Tyler|1989|page=119}}</ref> Cane toads from some populations can adjust their thermal tolerance within a few hours of encountering low temperatures.<ref name=":0">{{Cite journal|last1=McCann|first1=Samantha|last2=Greenlees|first2=Matthew J.|last3=Newell|first3=David|last4=Shine|first4=Richard|date=2014|title=Rapid acclimation to cold allows the cane toad to invade montane areas within its Australian range|url=https://onlinelibrary.wiley.com/doi/abs/10.1111/1365-2435.12255|journal=Functional Ecology|language=en|volume=28|issue=5|pages=1166–1174|doi=10.1111/1365-2435.12255|bibcode=2014FuEco..28.1166M |issn=1365-2435}}</ref> The toad is able to rapidly acclimate to the cold using physiological plasticity, though there is also evidence that more northerly populations of cane toads in the United States are better cold-adapted than more southerly populations.<ref>{{Cite journal|last1=Mittan|first1=Cinnamon S|last2=Zamudio|first2=Kelly R|date=2019-01-01|title=Rapid adaptation to cold in the invasive cane toadRhinella marina|url=https://doi.org/10.1093/conphys/coy075|journal=Conservation Physiology|volume=7|issue=1|pages=coy075|doi=10.1093/conphys/coy075|issn=2051-1434|pmc=6379050|pmid=30800317}}</ref> These adaptations have allowed the cane toad to establish invasive populations across the world. The toad's ability to rapidly acclimate to thermal changes suggests that current models may underestimate the potential range of habitats that the toad can populate.<ref name=":0" /> The cane toad has a high tolerance to water loss; some can withstand a 52.6% loss of body water, allowing them to survive outside tropical environments.<ref name="Tyler1989p119" />

===Diet===
Most frogs identify prey by movement, and vision appears to be the primary method by which the cane toad detects prey; however, it can also locate food using its sense of smell.<ref name="Lever2001p10">{{Harvnb|Lever|2001|page=10}}</ref> They eat a wide range of material; in addition to the normal prey of small [[rodent]]s, other small [[mammal]]s,<ref name="UWI">{{cite web|url=https://sta.uwi.edu/fst/lifesciences/sites/default/files/lifesciences/documents/ogatt/Rhinella_marina%20-%20Cane%20Toad%20or%20Crapaud.pdf|title=''Rhinella marina'' (Cane Toad or Crapaud)|website=Sta.uwi.edu|access-date=11 June 2022}}</ref> [[reptile]]s, other [[amphibian]]s, [[bird]]s, and even [[bat]]s and a range of [[invertebrate]]s (such as [[ant]]s, [[beetle]]s, [[earwig]]s, [[dragonflies]], [[grasshopper]]s, [[true bug]]s, [[crustacean]]s, and [[gastropod]]s),<ref name="Rhinella marina Cane Toad">{{Cite web|url=https://animaldiversity.org/accounts/Rhinella_marina/|title = ''Rhinella marina'' (Cane Toad)|website=Animaldiversity.org}}</ref> they also eat plants, dog food, cat food,<ref name="Rhinella marina Cane Toad"/> feces,<ref name="UWI"/> and household refuse.<ref name="Tyler1989pp130-132">{{Harvnb|Tyler|1989|pages=130–132}}</ref><ref>{{cite journal | last1 = Mikula | first1 = P | year = 2015 | title = Fish and amphibians as bat predators | journal = European Journal of Ecology | volume = 1 | issue = 1| pages = 71–80 | doi = 10.1515/eje-2015-0010 | doi-access = free }}</ref>

===Defences===
[[File:Bufo marinus01e.jpg|thumb|left|Specimen from [[El Salvador]]: The large parotoid glands are visible behind the eyes.|alt=An adult cane toad with dark colouration, as found in El Salvador: The parotoid gland is prominently displayed on the side of the head.]]

The skin of the adult cane toad is toxic, as well as the enlarged parotoid glands behind the eyes, and other glands across its back. When the toad is threatened, its glands secrete a milky-white fluid known as [[bufotoxin]].<ref name="Tyler1989p134">{{Harvnb|Tyler|1989|page=134}}</ref> Components of bufotoxin are toxic to many animals;<ref name="Tyler1989pp134-136">{{Harvnb|Tyler|1989|pages=134–136}}</ref> even human deaths have been recorded due to the consumption of cane toads.<ref name="issgBufoMarinus" />  Dogs are especially prone to be poisoned by licking or biting toads. Pets showing excessive drooling, extremely red gums, head-shaking, crying, loss of coordination, and/or convulsions require immediate veterinary attention.{{sfn|Brandt|Mazzotti|2005}}

[[Bufotenin]], one of the chemicals excreted by the cane toad, is classified as a schedule 9 drug under Australian law, alongside [[heroin]] and [[lysergic acid diethylamide|LSD]].<ref>{{cite web |title=Poisons Standard (No.2) June 2020 |url=https://www.legislation.gov.au/Details/F2020L00639/Html/Text#_Toc28084712 |website=Legislation.gov.au |publisher=Australian Government |access-date=7 June 2020 |language=en |date=June 2020}}</ref> The effects of bufotenin are thought to be similar to those of mild poisoning; the stimulation, which includes mild [[hallucination]]s, lasts less than an hour.<ref name="Fawcett2004-08-04p9">{{Harvnb|Fawcett|2004|page=9}}</ref> As the cane toad excretes bufotenin in small amounts, and other toxins in relatively large quantities, [[Psychoactive toad|toad licking]] could result in serious illness or death.<ref name="Weil1994pp1-8">{{Harvnb|Weil|Davis|1994|pages=1–8}}</ref>

In addition to releasing toxin, the cane toad is capable of inflating its lungs, puffing up, and lifting its body off the ground to appear taller and larger to a potential predator.<ref name="Tyler1989p134" />

Since 2011, experimenters in the Kimberley region of Western Australia have used poisonous sausages containing toad meat in an attempt to protect native animals from cane toads' deadly impact. The Western Australian Department of Environment and Conservation, along with the University of Sydney, developed these sausage-shaped baits as a tool in order to train native animals not to eat the toads. By blending bits of toad with a nausea-inducing chemical, the baits train the animals to stay away from the amphibians.<ref>{{cite web |url=http://www.abc.net.au/news/2011-12-15/can-toad-sausages-trialled-in-wa/3732836|date=15 December 2011 |title=Cane toad sausages served up in the Kimberley|publisher=ABC |access-date=2 March 2019}}</ref><ref>{{cite news|url=https://www.theguardian.com/environment/2018/mar/19/wild-quolls-take-bait-of-cane-toad-sausages-offering-hope-for-species|title=Wild quolls take bait of cane-toad sausages, offering hope for species|newspaper=[[The Guardian]]|access-date=2 March 2019|date=19 March 2018|first=Amy|last=McNeilage}}</ref><ref>{{cite web|url=https://www.abc.net.au/news/2018-06-16/toad-sausages-dropped-from-helicopters/9857520|title=First helicopter drops of cane toad sausages prompt design tweak|first=Erin|last=Parke|publisher=ABC|date=15 June 2018|access-date=2 March 2019}}</ref>

Young cane toads that aren't lethal upon ingestion have also been used to teach native predators avoidance, namely [[yellow-spotted monitor]]s. 200,000 metamorphs, tadpoles, and eggs in total were released in areas ahead of inevitable invasion fronts. Following invasion by wild cane toads, yellow-spotted monitors in control areas bereft of the "teacher toads" were virtually wiped out, but experimental areas still contained substantial populations of yellow-spotted monitors.<ref>{{Cite journal |last1=Ward-Fear |first1=Georgia |last2=Rangers |first2=Bunuba |last3=Bruny |first3=Miles |last4=Everitt |first4=Corrin |last5=Shine |first5=Richard |date=2024-04-08 |title=Teacher toads: Buffering apex predators from toxic invaders in a remote tropical landscape |journal=Conservation Letters |volume=17 |issue=3 |language=en |doi=10.1111/conl.13012 |issn=1755-263X|doi-access=free |bibcode=2024ConL...17E3012W }}</ref>

===Predators===
[[File:Kookaburra with Cane Toad - AndrewMercer - DSC00046.jpg|thumb|[[Laughing kookaburra]] (''Dacelo novaeguineae'') preying on a juvenile cane toad]]
Many species prey on the cane toad and its tadpoles in its native habitat, including the [[broad-snouted caiman]] (''Caiman latirostris''), the banded cat-eyed snake (''[[Leptodeira annulata]]''), eels (family [[Anguillidae]]), various species of [[killifish]],<ref name="Tyler1989pp138-139" />  and ''[[Paraponera clavata]]'' (bullet ants).<ref>{{Cite journal |last=Morrison |first=Colin R. |date=November 2018 |title=Predation of top predators: cane toad consumption of bullet ants in a Panamanian lowland wet forest |url=https://www.cambridge.org/core/journals/journal-of-tropical-ecology/article/abs/predation-of-top-predators-cane-toad-consumption-of-bullet-ants-in-a-panamanian-lowland-wet-forest/31E056A8BE4E3DAECE661E8E2A7E0ED6 |journal=Journal of Tropical Ecology |language=en |volume=34 |issue=6 |pages=390–394 |doi=10.1017/S0266467418000342 |issn=0266-4674}}</ref>

Predators outside the cane toad's native range include the rock flagtail (''[[Kuhlia rupestris]]''), some species of [[catfish]] (order Siluriformes), some species of [[ibis]] (subfamily Threskiornithinae),<ref name="Tyler1989pp138-139">{{Harvnb|Tyler|1989|page=138–139}}</ref> the [[whistling kite]] (''Haliastur sphenurus''), the [[rakali]] (''Hydromys chrysogaster''), the [[black rat]] (''Rattus rattus'') and the [[Asian water monitor|water monitor]] (''Varanus salvator''). The [[tawny frogmouth]] (''Podargus strigoides'') and the [[Papuan frogmouth]] (''Podargus papuensis'')<ref name="Angus1994pp10-11">{{Harvnb|Angus|1994|pages=10–11}}</ref> have been reported as feeding on cane toads; some Australian crows (''[[Corvus]]'' spp.) have also learned strategies allowing them to feed on cane toads, such as using their beak to flip toads onto their backs.<ref>{{cite web|first=Katrina|last=Bolton |url=http://www.abc.net.au/news/stories/2007/09/15/2033759.htm |archive-url=https://web.archive.org/web/20071209125627/http://www.abc.net.au/news/stories/2007/09/15/2033759.htm |url-status=dead |archive-date=December 9, 2007 |title=Toads fall victim to crows in NT – ABC News (Australian Broadcasting Corporation) |publisher=Abc.net.au |date=2007-09-15 |access-date=2011-11-12}}</ref><ref>{{cite web|url=http://www.ozanimals.com/Frog/Cane-Toad/Bufo/marinus.html |title=Cane Toad (''Bufo marinus'') |publisher=Ozanimals.com |access-date=2011-11-12}}</ref> [[Kookaburra]]s also prey on the amphibians.<ref>{{Cite news |date=2019-10-31 |title=The native animals that turn cane toads into tucker |language=en-AU |work=ABC News |url=https://www.abc.net.au/news/science/2019-11-01/cane-toad-native-animals-eating/11649498 |access-date=2023-10-06}}</ref>

Opossums of the genus ''[[Didelphis]]'' likely can eat cane toads with impunity.<ref>{{cite web|url=http://www.abc.net.au/rn/scienceshow/stories/2010/2850936.htm |title=American possums the solution to cane toads in Australia? – Science Show – 20 March 2010 |publisher=Abc.net.au |access-date=2010-04-26 |archive-url=https://web.archive.org/web/20100322225724/http://www.abc.net.au/rn/scienceshow/stories/2010/2850936.htm <!--Added by H3llBot--> |archive-date=2010-03-22|date=2010-03-19 }}</ref> [[Meat ant]]s are unaffected by the cane toads' toxins, so are able to kill them without reaction.<ref>{{cite news|url=http://www.timesonline.co.uk/tol/news/environment/article6007268.ece|title=Killer ants are weapons of mass toad destruction|last=Sweeney|first=Claire|newspaper=Times Online|access-date=2009-03-31 | location=London | date=31 March 2009}}{{dead link|date=September 2024|bot=medic}}{{cbignore|bot=medic}}</ref> The cane toad's normal response to attack is to stand still and let its toxin kill or repel the attacker, which allows the ants to attack and eat the toad.<ref>{{cite web|url=http://www.qm.qld.gov.au/Find+out+about/Animals+of+Queensland/Frogs/Cane+Toad|title=Cane Toads|publisher=Queensland Museum|access-date=2012-07-31|archive-url=https://web.archive.org/web/20150322180305/http://www.qm.qld.gov.au/Find+out+about/Animals+of+Queensland/Frogs/Cane+Toad|archive-date=2015-03-22|url-status=dead}}</ref> [[Saw-shelled turtle]]s have also been seen successfully and safely eating cane toads.

In Australia [[rakali]] (Australian water rats) in two years learnt how to eat cane toads safely. They select the largest toads, turn them over, remove the poisonous gallbladder, and eat the heart and other organs with "surgical precision". They remove the toxic skin and eat the thigh muscle. Other animals such as crows and kites turn cane toads inside out and eat non-poisonous organs, also thus avoiding the skin.<ref>{{cite news| last=Zhou | first=Naaman | title=Australian water rats cut cane toads open with 'surgical precision' to feast on their hearts |newspaper=The Guardian | date=25 October 2019 | url=https://www.theguardian.com/world/2019/oct/26/australian-water-rats-cut-cane-toads-open-with-surgical-precision-to-feast-on-their-hearts}}</ref>