Comparing big cats - differences/changes with time

[Pckts]

(02-17-2020, 07:26 PM)BlakeW39 Wrote:

(02-17-2020, 03:01 AM)Pckts Wrote: Competition in the pantanal is 2nd to none, but for the most part I agree with you.
But when you see Jaguars, you realize how similar their body is to a giant river Otter. 
Obviously they're still very different but, they still share similarities that no other big cat shares.
This has got to do with the fact that they're hunting animals that are more adept in the water than land.
I'm not saying that they'll stop running on land, I'm just comparing their features to that of a specialized aquatic predator.

In regards to large mammals, they dont occur nearly as often in north, whether due to human hunting or Jaguar densisty is up for debate but regardless, they just dont exist like that in the North. The main animals you see there are capybara and Caiman. 
They're both very adept swimmers and never stray far from the waters edge. They also usually sit with one another so they probably require the same tactics. 

Tapir are no slouch, they can be double the size of a male jaguar.
But they are predated on more often in the areas they are more abdundent.
Put it this way, if you go on safari in the northern pantanal, the odds of you seeing a tapir are 1/100.

Well competition in the Pantanal is high (not sure if I'd say second to none though) with pumas, caimans, and anacondas. I was mostly speaking of terrestrial predators, though.

But yeah I definitely see their similarities with river otters. I think these characteristics are derived from different naturally selective pressures, though; the jaguar's long, flexible spine, for instance, is an adaptation for a different behavior than is the similarly long and flexible spine of the otter. The former is for great agility & athleticism for predation, while the latter is for swimming.

I totally agree that jaguars are the most aquatic of the big cats, mostly due to the fact which I stated on them taking advantage of a diverse prey base that largely includes semi-aquatic animals. But jaguars are generalists, and I doubt they'd specialize in this aquatic prey when they also take other animals, like giant anteaters.

Yeah tapirs aren't slouches, though they should be well within the capabilities of a jaguar sized felid. It's also worth noting that they're also rather aquati, and they're largely nocturnal. They also live at low densities being large solitary animals with rather slow maturation and gestation periods. But nevertheless mammalian megafauna don't make up a significant portion of the jaguars diet in way it usually does for the other extant big cats.

In regards to competition, I'm speaking on intraspecific ones. In that regards, I'd say the jaguar has the highest densisty of cats in a localized area.
And I'm not talking about females and cubs, I'm talking about adult specimens and mostly males.
In the meeting of the 3 rivers *tourism zone of the northern pantanal* there were 65 identified adult individuals last season. Cubs there are rarely seen and usually are pushed out to never be seen again. 

Tapir are rarely seen in the north, in the south they are seen more often but still rare.
My theory is the reason tapir and green anaconda are rarely seen in the north is because of the densisty of Jaguars. Both are slowing moving animals that may prefer a more vast space with a lower density of Jaguars.
It's kind if a perfect storm in the north, caiman were hunted and killed by the millions, decreasing jaguar numbers and increasing piranha numbers, when protection was finally offered to Caiman, they rebounded fast due to the increase in piranha after missing their main predator.
Now Caiman are everywhere, same with Capybara and both are mostly aquatic animals.
Cattle is a large ungulate and obviously easily killed by Jaguar. Tapir are going to be a tough animal to kill for any cat, especially one that they are double the size of.
Boar that are equal size as cats can be extremely tough prey, when they're double the size of a cat they are going to be very dangerous prey.

Lastly, in regards to their spine, it definitely contributes to Jaguars agility in the water.
They are so comfortable in the water and make kills in the water as well then they need to swim animals from the water up a steep, slippery slope and through dense floating grass.
It's a perfect combination of flexibility and strength, but with the ever changing habitat and aquatic prey preference, it should only benefit the Jaguar to continue its aquatic evolution imo. Reply