There will be a dispute about this but I believe that I have a definitive record for the largest or heaviest (should be the same) mountain lion on record because it was certified by the U.S. Biological Survey. The cat was an Arizona puma killed in 1917 by a predator hunter i.e. a sport hunting human.
It must have pleased him to have killed such a magnificent creature. Without intestines (removed for some reason perhaps to preserve the body) the cat weighed 125 kilograms. This is 276 pounds. If you add back the intestines which at a guess would have weighed several pounds you could argue that this cat weighed in the region of 280 pounds.
The source of this information is:
Young S.P. 1946 History, life habits, economic status, and control, part 1. In S.P. Young and E.A. Coleman, The Puma, mysterious American cat, 1-173. Washington, DC: American Wildlife Institute. This reference is used by Wild Cats Of The World by Mel and Fiona Sunquist at page 254.
This is considerably more that the reported number referred to by Wikipedia: 1901 – 232 pounds. They say the 276 pound weight is unreliable and might have been exaggerated.
I disagree because it was certified. An exaggerated record might be the 170 kilogram weight of a puma killed in 1958 in the Chaco region of Paraguay reported in Sports Afield Hunting Annual. This is 375 pounds.
The weights of pumas vary hugely over their large geographic range across north, central and south America. You’d be surprised to read that pumas in equatorial forests in Peru weigh between 28 and 30 kilograms (62-66 pounds). This is not much larger than a medum-sized wild cat.
There is also a wide divergance in weight between males and females. Males weigh 40-60 percent more than females and are larger in all body measurements. It is believed that the difference is due to sexual selection. I take this to mean that females select large males with whom to mate.
SOME ON WILD CAT SPECIES BY SIZE:
I enjoyed reading your description of your encounter with a large puma. It paints a very clear picture which is useful to me because I like to get a sense of what it’s like to encounter such a majestic creature. And well done in not harming the creature. In my book they have a right just like us to live in their world. They grace our world with their presence. And they can be scared away. The experts say that you can do it even without a gunshot. Whenever there is an attack by a puma on a person is almost invariably on a child or a woman. And there will be a reason behind it such as a mother defending her cubs. They deserve to be left alone in my opinion and humans should always try and provide some space for them so that we can live in harmony with them.
I Live on 21 acres up against a national forest in California and lucky enough a large male cougar frequents the area. One night I had heard a deer passing through(they are ridiculously loud on the dry underbrush) so I kept looking that direction as I got my wood stove going. About third glance over my shoulder, I see what at first made me think of two pieces of reflective tape, as my eyes adjusted I noticed it was in fact a large cat crouched low and getting ready to jump… on me lol. Quickly thinking I don’t want to deal with over 100lbs of dead cat, plus I like nature so didn’t want to kill it, so I pulled my gun from my holster and shot in its direction, purposely missing the huge cat. It obviously took off bounding loudly down a near by gully. Next morning I see that it’s paws were 9 feet from front to back! I was in shock, that’s a big friggn kitty, that almost tried to eat me. Seen the bastard twice since. Once after loading wood into my truck and getting in, seen him in my mirror about 10 feet away, freakishly big head. Almost cartoonish it was so big, I see why many locals don’t go outside after dark, and have a new respect for the forrest at night. Over 500 camping trips growing up and never seen one so close. On my trail cameras they look as big as the tigers at the zoo it’s awesome and a little spooky.