Tourists Get Very Close to Huge Estuarine Crocodile

Many visitors to the Northern Territories of Australia like to get up close to the amazing wildlife of the region. Sure, Australia has cute and cuddly kangaroos and koala bears but for one group of boat trippers out to spot crocodiles they got a little too close a view of one river giant – an eighteen-foot-long Saltwater crocodile called Brutus.

Crocodile

The incredible animals of Australia, both extinct ones and those creatures that are very much alive and kicking, have been in the news a lot over the last few days.  Last week, Everything Dinosaur reported on the discovery of a very well preserved giant wombat fossilised skeleton that had been found in Queensland.

To read more about this: Outback Dig for Giant Wombat Fossil.

However, the tourists on a river cruise got their own encounter with a giant creature from Australia, one of the most dangerous animals on the planet – a giant Saltwater (Estuarine) crocodile.  The crocodiles are attracted to the pleasure crafts by tour guides who dangle kangaroo meat on poles.  The crocs soon learn to associate the river cruisers with food and they tend to congregate in the hope of getting an easy meal.

Beaware of Brutus

The crocodile, nick-named Brutus is certainly a very impressive beast, perhaps weighing as much as 1200 kilogrammes and measuring almost six metres in length.  This male croc is believed to be one of the largest in the Darwin river system. It is missing its right front limb, perhaps as a result of a fight with a shark or another crocodile.  The loss of the limb does not seem to have affected this crocodile’s ability to leap out of the water to grab the food on offer.  The power to propel them several metres out of the water is generated by their immensely strong tail muscles.

This is certainly one holiday “snap” that will be remembered.  Although such tourist activities brings in much needed income and plays a role in educating visitors to the area about the dangers of crocodiles the number of large crocodiles in the Northern Territories is a cause for concern amongst government officials.  There have been several crocodile attacks in the last few months, including fatalities, the number of such incidents is on the increase as the crocodile population continues to bounce back after years of illegal hunting.

To read about a recent crocodile attack: Crocodile Sinks Teeth into Dentist.

This close encounter with Brutus may lead to more calls to restrict the number of river tours and there has already been discussions regarding a cull of crocodiles in the Darwin river system.

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New Research shows that Cuban Crocs are Hybridising with American Crocodiles

It is always refreshing to see representatives of Cuba getting on with Americans but for the Cuban crocodile (Crocodylus rhombifer) things may be going too far as new research suggests the rare Cuban crocodiles are cross-breeding with American crocodiles and this could have stark consequences for both species.

Crocodiles

A new genetic study by a team of Cuban and American researchers confirms that American crocodiles (Crocodylus acutus) are hybridising with wild populations of critically endangered Cuban crocodiles, which may cause a population decline of this species found only in the Cuban Archipelago.

Cuban crocodiles and American crocodiles have been confirmed to interbreed in captivity and were suspected to hybridise in the wild, but until this new study, there had been no scientific proof that this was happening.  This is the first genetic study that confirms wild hybridisation., between these two species of crocodile.

The study, which appears in the spring issue of the scientific publication “The Journal of Experimental Zoology”, provides definitive genetic evidence that interbreeding is taking place in the wild and that these two types of crocodile are very closely related.

The Difference Between a Crocodile and an Alligator

Crocodile (top) and Alligator (bottom).

Known for their leaping ability and aggressive disposition, Cuban crocs are a charismatic and culturally significant species to Cuba.  Exact population estimates for the species remain unknown, though scientists believe that a minimum of 3,000 individuals remain in the Zapata swamp.  A smaller population exists in the Lanier Swamp on the Island of Youth.  The species was extensively hunted from the middle of the 19th Century through to the 1960s resulting in drastic population declines.

The team collected and analysed DNA from 89 wild-caught Cuban and American crocodiles and compared this genetic material with two samples from crocodiles kept in captivity.

The genetic data produced an unsuspected result,  American crocodiles in Cuba are more closely related to Cuban crocodiles than other American crocodile populations found along mainland Central America.  The study found just a 1 percent genetic sequence divergence between Cuban crocodiles and American crocodiles in Cuba yet an 8 percent divergence between American crocodiles in Cuba and other American crocodile populations living in mainland Central America.

This finding indicates that Cuban crocodiles and American crocodiles in Cuba may represent two evolutionary significant units (ESU’s), populations considered distinct for conservation purposes and represent an important component of the evolutionary legacy of the species.

The researchers say that hybridisation may be one of the most important threats to Cuban crocodiles, along with illegal hunting and habitat modification.  Hybridisation can result in both replacement and genetic mixing, and one lineage may cause the extinction of another.  The authors of the paper, whilst commenting on the significance of their discovery have expressed grave concerns over their findings for the preservation of the Cuban crocodile.  They have called upon Government agencies to take steps to avoid interbreeding in the wild and to ensure that the physical separation and segregation of these two species be considered in future conservation programmes.

The crocodiles of Central America have been in the news recently, as there have been moves to take away the protected status of the rare Mexican crocodile.

To read an article about this: Crocodile to Lose its Protected Status.

Although rare in the United States, the American crocodile has a much wider distribution than the Cuban crocodile and is therefore under less threat of extinction.

For models and replicas of crocodiles and alligators (whilst stocks last): Mojo Fun Prehistoric and Extinct Models and Figures.

The Bird that has Forgotten that it Cannot Fly

New Zealand has a number of flightless birds, one of the country’s national symbols is the bizarre Kiwi and until very recently this remnant of Gondwanaland was home to one of the largest members of the Aves that ever existed – the Moa.  Whilst reading the excellent “The Greatest Show on Earth – the Evidence for Evolution”, a book written by Richard Dawkins, we came across a passage about another one of New Zealand’s indigenous, flightless birds – the Kakapo.

The Kakapo

The lack of mammals on the islands that make up New Zealand led to birds, that has reached this isolated landmass taking up those niches in the food chains that were occupied by mammals elsewhere in the world.  The Kakapo is a parrot, its ancestors could fly but it adapted to a life on the ground and as a result it lost the ability to fly.  With large adults weighing as much as 3 kilogrammes, these birds are rather ungainly.  They are slow moving and can manage to waddle around, but flying as their ancestors did is out of the question.  The Kakapo’s wings cannot support the weight of such a heavy and cumbersome bird, indeed, the Kakapo is the world’s largest parrot.

It may also be the longest-lived bird in the world, with a suspected life expectancy of about 90 years. None of the Kakapos known to scientists have yet died of old age and the chances are that some of the youngsters will out-live the people who are studying them.  Perhaps this is because they seem to do everything more slowly than other birds, these creatures tend to live life in the “slow lane”.

The Largest Parrot in the World

As pictures show, these strange birds still venture into trees, it seems that the Kakapo has forgotten that it cannot fly.  Richard Dawkins, quotes the writer Douglas Adams who commented on this bizarre parrot for a television series called “Less Chance to See” thus:

“It is an exceptionally fat bird (a good-sized adult weighs roughly six or seven pounds) and its wings are just about good enough to waggle about a bit if it thinks it’s going to trip over.  But flying is completely out of the question.

Strangely, not only has it forgotten how to fly, it also seems to have forgotten that it has forgotten how to fly.  Legend has it that a seriously worried Kakapo will sometimes run up a tree and jump out of it, whereupon it flies like a brick and lands in a graceless heap on the ground.”

Nocturnal Birds

The birds are almost entirely nocturnal and are one of the slowest breeding birds none to science.  Not a problem when once there were hundreds of thousands of them living all over New Zealand but Maori hunters and the white settlers took their toll on these birds who were very easy to catch.  The Kakapo’s habitats were destroyed to make way for farming and the human settlers introduced mammalian predators to New Zealand – cats, dogs and rats.

The Kakapo was driven to the point of extinction, numbers got as low as perhaps forty.  However,  in 1989, a remarkable preservation strategy was put in place by the New Zealand government to try to prevent this unique animal from dying out.  The Kakapo Recovery Plan was developed to translocate all the remaining Kakapos to carefully-prepared, predator-free islands for safe-keeping.  It seems to be working – the population has reached a total of nearly one hundred so far. It’s a positive first step towards recovery, albeit a tentative one.

Natural selection led to the Kakapo losing its ability to fly, this left it vulnerable to predators once they were introduced to its island home.  With luck and care (and the dedication of a team of hard-working scientists), this strange, night parrot might just have a future.

For dinosaur models, toys and gifts: Everything Dinosaur.

Dentist Survives Saltwater Crocodile Attack

A dentist fishing with friends got more than he bargained for when he was savagely attacked by a 2.5- metre-long Saltwater Crocodile.  The attack which left the dentist with puncture wounds and gashes to his upper chest was swiftly curtailed by a elbow to the throat of his assailant.

Saltwater Crocodile

Dentist Bruce Rudeforth, from Broome (Western Australia) survived the attack from a two and a half metre long Saltwater crocodile (Crocodylus porosus) which leapt into his fishing dinghy and clamped its jaws around his upper chest.  The 59-year-old, experienced fisherman was busy baiting up his lines last Wednesday afternoon, hoping to catch a Barramundi or two when the unexpected assault took place.  The attack happened in Secure Bay, an area known to be frequented by many large crocodiles, but such aggression is rarely encountered.

Dr Rudeforth stated:

“Out of the corner of my eye, this came at me.  It bit into my shoulder and I stood up and gave it one in the throat with my free elbow – I presume that is what made it let go.”

The crocodile remained in the dinghy for several seconds and it was touch and go whether it would lunge again, according to Dr Rudeforth.

The Difference Between a Crocodile and an Alligator

Crocodile (top) and Alligator (bottom).

For models and replicas of crocodiles and alligators (whilst stocks last): Mojo Fun Prehistoric Life Models.

Dr Rudeforth was bleeding underneath his shredded shirt, but the encounter with this predator was not over.  After the crocodile had disappeared underwater it returned again, forcing the dentist and his fishing mate Neil Fong to defend themselves with the boat’s oars.

Dr Rudeforth added:

“With the other hand I had the outboard started and we were going backwards at a million miles an hour.”

Once the pair made it back to a bigger boat, where their three other fishing colleagues were, Dr Rudeforth was treated by his brother-in-law and fellow Broome dentist Peter Ellies.  Dr Ellies used a local anaesthetic from the boat’s first aid kit to numb the pain and stitch the wounds.

Rather than call off the week-long trip, with typical Aussie gusto, Dr Rudeforth decided to continue fishing with stitches in the wounds for several days.

He commented:

“It takes a lot to organise a trip like that, so why come home.”

Undeterred by his experience the doctor has not been put off returning to Secure Bay, but he warned other visitors that the behaviour of the crocodiles in the area may have changed.

Not long before the attack, he and the other man had caught two Barramundi and lost two others while fishing along the side of a creek.  He stated that the attack came without any warning.

“We have been doing this for years and years and there are always crocodiles around.  They usually hang out at a comfortable distance, just waiting for you to make a mistake, but on this trip we had lots of episodes where they came right at us and were aggressive.”

He had one theory that as more and more people ventured into the area, they might be feeding the crocodiles in some way.

Feeding crocodiles is a very dangerous practice, he added:

“That is causing them [crocodiles] to associate humans with food.  It that’s the case, then there will be more and more of this sort of stuff happening.”