Crocodile, the killler of water

[Paleosuchus]

Nile crocodiles in Florida
MOLECULAR ANALYSES CONFIRMING THE INTRODUCTION OF NILE CROCODILES, CROCODYLUS NILOTICUS LAURENTI 1768 (CROCODYLIDAE), IN SOUTHERN FLORIDA, WITH AN ASSESSMENT OF POTENTIAL FOR ESTABLISHMENT, SPREAD, AND IMPACTS
Abstract
—The state of Florida, USA, has more introduced herpetofauna than any other governmental region on Earth.
Four species of nonnative crocodilians have been introduced to Florida (all since 1960), one of which is established.
Between 2000–2014 we field-collected three nonnative crocodilians in Miami-Dade County, Florida, and one in Hendry
County, Florida. We used DNA barcoding and molecular phylogenetics to determine species identification and native
range origin. Also, we described diet, movement, and growth for one crocodile. Our molecular analyses illustrated that
two of the crocodiles we collected are most closely related to Nile Crocodiles (Crocodylus niloticus) from South Africa,
suggesting this region as a source population. We, thus, documented the first known introduction of C. niloticus in
Florida. Two, and possibly three of the introduced crocodiles shared the same haplotype, suggesting they are likely from
the same introduction pathway or source. One animal was captured, measured, marked, and released, then recaptured 2
y later allowing us to calculate growth rate (40.5 cm/y) and movement. The most likely route of travel by waterway (i.e.,
canal) illustrates that this animal traveled at least 29 km from its original capture site. One crocodile escaped from a
facility in Hendry County, Florida, and survived in 1,012 ha of semi-wild habitat for three to four years, confirming that
this species can survive in southern Florida.

*This image is copyright of its original author

"The first crocodile (approximately 1.2–1.5 m TL; photographic voucher
UF-Herpetology 175632) in this study escaped from its
enclosure in 1996 or 1997 at Billie Swamp Safari,
Seminole Reservation, Hendry County (26.330348°N,
81.055936°W; datum WGS84; Jonathan Vasquez, pers.
comm.). This crocodile was somewhat contained by a
perimeter fence within the 1,012 ha property. In 2000, it
was finally recaptured by Billie Swamp Safari staff and
measured 3 m TL. We were unable to secure a tissue
sample from this crocodile.
The second crocodile (UF-Herpetology 175743), a
hatchling, was captured by Robert Freer on 14 April
2009 on the house porch of a resident at 24800 SW 193
Avenue, Miami, Miami-Dade County (25.534833°N,
80.504653°W), and subsequently transported to
Kliebert’s Turtle and Alligator Farm in Hammond,
Louisiana. In June 2015 we acquired a tissue sample
from this crocodile. The third crocodile (UFHerpetology
165995) was a female captured on 27
October 2011 at the Preston B. Bird/Mary Heinlein Fruit
and Spice Park, Homestead, Miami-Dade County
(25.53385°N 80.49348°W; datum WGS84; Fig. 1), and
subsequently kept in captivity by JAW. It measured
57.7 cm SVL, 115.2 cm TL, 15.3 cm HL, and weighed
4.4 kg.
The fourth crocodile (UF-Herpetology 173082) was a
female (86.3 cm TL) captured on 13 March 2012 in a
canal in Homestead, Miami-Dade County (25.50632°N,
80.47343°W). This crocodile was released and
recaptured 9 March 2014 in Everglades National Park
(ENP; 25.61707°N, 80.5753°W; U.S. National Park
Service, unpubl. report), and measured 23.6 cm HL, 88.0
cm SVL, 167.9 cm TL, 43.6 cm TG, and weighed 17.0
kg. Its stomach contained remains of a Largemouth
Bass (Micropterus salmoides). Straight-line distance
over land between primary and secondary capture sites
was 16 km; however, the most likely route of travel by
canal was 29 km."

*This image is copyright of its original author

http://redirect.viglink.com/?format=go&jsonp=vglnk_148130480825112&drKey=1082&libId=iwi2l63901000bl0000DA19557j3x&loc=http%3A%2F%2Fcarnivoraforum.com%2Ftopic%2F9333527%2F2%2F&v=1&out=http%3A%2F%2Fwww.researchgate.net%2Fprofile%2FMatthew_Shirley2%2Fpublication%2F301790746_MOLECULAR_ANALYSES_CONFIRMING_THE_INTRODUCTION_OF_NILE_CROCODILES_CROCODYLUS_NILOTICUS_LAURENTI_1768_CROCODYLIDAE_IN_SOUTHERN_FLORIDA_WITH_AN_ASSESSMENT_OF_POTENTIAL_FOR_ESTABLISHMENT_SPREAD_AND_IMPAC%2Flinks%2F5728976608ae0acc4f49a9aa.pdf&ref=http%3A%2F%2Fcarnivoraforum.com%2Ftopic%2F9333527%2F1%2F&title=Nile%20Crocodile%20-%20Crocodylus%20niloticus&txt=%3Cfont%20color%3D%22blue%22%3ELink%20to%20study%3C%2Ffont%3E

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Post i made on the size of Nile crocodiles
"A large male nile crocodile would be in the ball park of 5-5.5m in total length and a mass of 600-700kg; Gerard wood, in his guiness book of animal facts & feats, wrote on an animal measuring 5.8m in total length with an estimated mass of 794-816kg, and a 4.8m animal weighing in at 680kg, all of these are of course a lot bigger than the largest lions. the figure in the OP describing the record length of a nile crocodile is an estimate, presented in Wood(1983), the slightly lower figure presented was 2300lbs. not significant but warranting clarification i guess. 


The thing with crocodiles is not as tricky as it commonly portrayed to be, like a lot of large predators with wide geographic ranges they vary tremendously.  ~3-4.5 is what you can expect a typical adult nile crocodile to measure in total body length. They mature around 2.5m in total body length, with this of course varying from population to population(lake rudolph males matured at either 1.8 or 3.3m in total length at extremes) as well as sex(lake rudolph females matured at 1.7 or 3.0 in total length at extremes), but these animals shouldn't really be regarded in this match up, as a young crocodile against an adult lion is very one sided. Now here is a very large (500+) sample of animals from different localities that should clear up what a typical nile will weigh, of course taking the bit i've written about sexual maturity into consideration."

*This image is copyright of its original author

From Graham(1968)(click it)

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Terrestrial hunting in nile crocodiles, from Vladimir Dinets:
"Crocodilians are generally considered to
be specialised predators hunting in the water
or at the water edge (Neil, 1971). Their terrestrial
activities such as nesting, migrating, aestivating/
hibernating and basking are well known and
documented in most overviews of crocodilian
biology. Despite abundant anecdotal evidence
of terrestrial hunting (mostly in the form of
scary campfire stories), this aspect of crocodilian
behaviour has never been studied nor scientifically
described. Observations made during a study of
crocodilians in the wild in 2006-2010, mostly on
American alligator (Alligator mississippiensis),
Nile crocodile (Crocodylus niloticus), and to
a lesser extent on other species, suggest that
terrestrial hunting may be more common than
previously thought."

Nile crocodiles(Crocodylus niloticus)
Pooley (1982) mentioned his observation of two
Nile crocodiles carrying a recently killed Nyala
(Tragelaphus angasii) overland, but it was not
clear if the animal had been killed on land.
In September 2008 in South Luangwa National
Park (Zambia), at 02:15, I observed a 2.5 m Nile
crocodile unsuccessfully chase a juvenile Bushbuck
(Tragelaphus sylvaticus) for 5-6 m across a dry,
elevated river terrace at least 100 m from the water
edge. Interviews with local hunters, safari guides
and game rangers suggested that Nile crocodiles
are occasionally seen on roadsides during night
drives in South Luangwa and Lower Zambezi
National Parks (Zambia), Mudumu and Mamili
National Parks (Namibia), Chobe and Moremi
National Parks (Botswana), Lilongwe National
Park (Malawi), and Murchison Falls National Park
(Uganda).
I have observed terrestrial behaviour at the
Oromo River Delta, Ethiopia (n=1 in 44 hours of
nocturnal searching), Mahango Game Reserve,
Namibia (n=2 in 56 hours of nocturnal searching and
driving), and at Simangaliso Wetland Park, South
Africa (n=1 in 6 hours of nocturnal searching)
Terrestrial behaviour on these occasions was
always by crocodiles of between 2-3.5 m. In the
latter case, a 2.5 m long crocodile was observed
catching and swallowing a large toad (Bufonidae)
as it was moving along the trail. Once located,
each crocodile was observed for 20-30 min to see
if it would start moving, but no attempts to change
location were ever seen. The fact that predation
attempts were seen twice in less than 2 hours of
observing Nile crocodiles on land at night suggests
that terrestrial hunting is possibly an effective
alternative hunting strategy."
http://dinets.info/Pages%20from%20Bulletin%20114%20Dinets.pdf

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