Posts Tagged ‘caiman’

Big Cats vs. Crocodilians

March 17, 2015

The Mcbrides track cougars (Puma concolor) for the Florida Department of Natural Resources.  Roy Mcbride began tracking Florida panthers in 1972 when there was some doubt over whether this species still existed in state.  (The Florida panther is the same species as the cougar but I prefer using the latter common name.)  A few years ago, the Mcbrides interrupted a cougar feeding upon an alligator it had killed.  They treed the cat and examined the alligator.  Cougars were known to occasionally prey on smaller alligators, but the Mcbrides were surprised at the size of this specimen.  It measured 8 feet, 8 inches–the largest gator ever known to be killed by a cougar.  The cougar had eaten the brisket (chest area) of the gator but was so spooked by the trackers it never returned to the carcass.  The Mcbrides published their discovery in the Southeastern Naturalist.  Below is the 1st page of the 2 page article.

Cats are courageous hunters. Still, it seems unexpected that they would take on such a dangerous choice of prey.  Nevertheless, caimans make up a significant portion of the jaguar’s diet in certain parts of the Amazon jungle.

Jaguar attacks a Yacare Caiman

Jaguar killing caiman.

Leopards and tigers rarely prey on crocodiles, yet they have been recorded slaying them.

Photobucket

This leopard actually dragged the crocodile from the water onto land and killed it.

Youtube video of a tiger killing a crocodile.

A big cat’s strategy for hunting a crocodilian is cunningly effective.  They attack from behind, get a good grip on the reptile, and bite through the braincase, killing it instantly.  They don’t just ambush crocodilians sunning themselves on the riverbank.  The leopard in the above photos dove into the water and yanked the crocodile from its own element.

I wonder if saber-tooths (Smilodon fatalis) ever attacked alligators.  Saber-tooths had a weaker bite force than any species of extant big cat.  Their big canines would have been at risk of breaking, if they tried to bite through an alligator’s skull.  However, they were very powerful and would have been capable of rolling the alligator on its back and slicing through its throat with their fangs.  Jaguars were 1 of the most common large predators in southeastern North America during the Pleistocene and undoubtedly took a toll on alligators here then.

Reference

Mcbride, Roy; and Cougar Mcbride

“Predation of a Large Alligator by a Florida Panther”

Southeastern Naturalist 9 (4) 2010

Alexander Von Humboldt’s Journey on the Apure River

September 10, 2013

I wish I could time travel to the Pleistocene and take a boat ride on one of Georgia’s major rivers, such as the Savannah, Altamaha, or Chattahoochee.  I would love to write an account of that experience.    Most people don’t realize how utterly devoid of wildlife the modern world is compared to the time before man decimated nature.  Alexander von Humboldt’s boat ride on the Apure River in 1800 may be the closest real life experience anyone has ever recorded that might be comparable to my wishful journey.  Humboldt traveled throughout the Spanish-claimed colonies of South America between 1799-1804.  For over 50 years after this, he was the sole scientific source of knowledge on the nature of South America.  The Spanish government granted permission to this German scientist to make a scientific expedition through their colonial territories.  This was unusual because the rulers of Spain were influenced by the Catholic Church and didn’t understand the value of science.  Paranoid authorities there assumed foreigners who wanted to travel in their colonies were spies working for enemy governments interested in fomenting revolutions that would result in Spain losing their New World territories. 

The Apure River is located in what today is Venezuela.  At the time of Humboldt’s journey it flowed through one of the more remote regions where few missionary settlements had been established.  The wildlife present then was rich in numbers and diversity.  Many of the same or similar species lived in Georgia during the Pleistocene.  This explains why this part of his journey holds such a fascination for me.

Map of Alexander Humboldt’s scientific expedition from 1799-1804.  This journey provided most of the scientific knowledge in Europe of South America’s natural history for over 50 years because the Spanish and Portuguese governments normally forbade scientific explorations of their colonies.

The Apure River flows through the Apure State in Venezuela.  It empties into the Orinico River.  Alexander Von Humboldt journeyed on this river circa 1800.

Humboldt, and his companion, Bonpland, made the journey with the governor’s brother-in-law, a pilot, and 4 Indian oarsmen.  They used a pirogue made from oxhides stretched over a wooden frame.  The cabin on the boat had a thatched roof.  For food and drink they carried chickens, eggs, cassava, chocolate, oranges, tamarinds, sherry, and brandy.  But the majority of their diet came from animals they hunted including manatees, capybaras, turtles (and their eggs), chacalacas, and currasows–the latter 2 being chicken-like birds.  (Humboldt pronounced manatee as delicious.) They also ate fish both fresh and dried and made into meal.  They used lances more than firearms because the latter often didn’t work in the humid climate.

They suffered from mosquitoes, gnats, and a type of insect that burrowed under their toe and finger nails.  The mosquitoes are so bad in this part of the world that the customary salutation is “How bad were the mosquitoes last night?” instead of “hello” and “goodbye.”  Nevertheless, Humboldt thought the trip was worth the torment just to see all the wildlife.

Humboldt wrote that 4 or 5 caimans, which he referred to as crocodiles, were always in view of the pirogue.  Thick hedges grew alongside the river, interrupted by passages made by peccaries and tapirs that used the same paths daily to access the drinking water.  Neither showed any fear of man.  Both were spotted by Humboldt’s party frequently along with the occasional deer.  Manatees and pink dolphins, known as toninas by the Spanish, swam in the main river channel and in the flooded plains and forests.  Manatees were so abundant that 1 region of the river was called Cano de Manatee.  Clouds of birds flew in the sky, and Humboldt noted the cries of herons, spoonbills, and flamingos were constant.  The presence of pirhanas annoyed Humboldt who wanted to bathe his itchy mosquito bites but feared the vicious “caribe” fish.  When they camped at night, the jungle was alive with the sounds of monkeys, sloths, and jaguars.  Vampire bats fluttered around their camp, and even fed on the blood from Humboldt’s dog.

During the rainy season the Apure River flooded the nearby grasslands turning it into a massive lake.  The floodwaters often rose so fast that horses drowned, attracting caimans and huge flocks of vultures.  Caimans occasionally attacked swimming horses that hadn’t drowned yet.  After the waters receded, some caimans dug holes in the savannahs and hibernated til the floods returned.  One time. Humboldt’s party was startled when a caiman emerged from the ground under a tent where they’d spent the night.  The reptile sprinted through the tent toward the river.  The floods caused some river banks to be covered in sand and silt rather than hedges.  Ten or more caimans often sunned themselves on these beaches.

Herds of 50-60 capybaras could be found everywhere on the Apure.  They were the main food of the surprisingly common jaguars.  Humboldt’s party had numerous encounters with the big cats.  His party saw a very large jaguar that Humboldt said was bigger than any tiger he’d ever seen in a European zoo.  Humboldt said the jaguars here were no danger to man because they had plenty of capybaras to prey upon, though on another river later in his expedition he lost his dog, a mastiff, to a jaguar.  Mastiffs are large dogs, sometimes weighing in excess of 100 lbs.  Nevertheless, 1 particular jaguar viewed it as food.

Capybaras were extremely abundant along the Apure River during Humboldt’s journey, and they helped support very large jaguar and caiman populations.  Two species of capybaras lived along Georgia’s coastal plain rivers during the Pleistocene.

Humboldt walked right by a large jaguar while collecting plants.  It scared the shit out of him, but he walked slowly back to camp, so the jaguar wouldn’t be incited by his flight to attack.  Jaguars were one of the most common large predators in southeastern North America during the Pleistocene.

Humboldt feared that he would become a jaguar’s dinner as he relates in the following account.

I left my companions while they beached the boat and prepared the meal.  I walked along the beach to observe a group of crocodiles asleep in the sun, their tails, covered with broad scaly plates, resting on each other.  Small herons, white as snow, walked on their backs, even on their heads, as if they were tree trunks.  The crocodiles were grey-green, their bodies were half covered in dried mud.  From their color and immobility they looked like bronze statues.  However, my stroll almost cost me my life.  I had been constantly looking towards the river, and then, on seeing a flash of mica in the sand, I also spotted fresh jaguar tracks, easily recognizable by their shape.  The animal had gone off into the jungle, and as I looked in that direction I saw it lying down under the thick foilage of a ceiba, eighty steps away from me.  Never has a tiger seemed so enormous.

There are moments in life when it is useless to call on reason.  I was very scared.  However, I was sufficiently in control of myself to remember what the Indians had advised us to do in such circumstances.  I carried on walking, without breaking into a run or moving my arms, and I thought I noted the wild beast had its eye on a herd of capybaras swimming in the river.  The further away I got the more I quickened my pace.  I was so tempted to turn around and see if  the cat was chasing me!  Luckily, I resisted this impulse, and the tiger remained lying down.  These enormous cats with spotted skins are so well fed in this country well stocked with capybara, peccary, and deer that they rarely attack humans.  I reached the launch panting and told my adventure story to the Indians, who did not give it much importance.”

Reference:

Alexander Von Humboldt: Personal Narrative of a Journey to the Equinoctial Regions of the New Continent

Penguin Books 1995