There is a world somewhere between reality and fiction. Although ignored by many, it is very real and so are those living in it. This forum is about the natural world. Here, wild animals will be heard and respected. The forum offers a glimpse into an unknown world as well as a room with a view on the present and the future. Anyone able to speak on behalf of those living in the emerald forest and the deep blue sea is invited to join.
(04-19-2022, 03:50 AM)Twico5 Wrote: You claimed that jaguars are on a different tier or level. I strongly disagree. In captivity they weigh the same. In places where both cats have similar mean prey weights, they will also weigh around the same. I dont think theres a need to continue this because as i said from the very start i believe it is unfair for us to compare pantanal jags to any population of pumas and as long as you keep on bringing them up i will continue to say this. Pumas can be just as long and just as tall so if a population of jags and pumas are eating the same they WILL have similar body masses wether the jaguar wins in a fight or not.
I suggest everyone to stop mention this "winning a fight" topic, we are on wildfact and we don't want discussions here to turn into VS debates at Carnivora trash forum level.
Regarding the rest, the idea that jaguars and cougars grow to the same size with the same food input is so wrong but nothing will stop the anti-jaguar crowd from spreading their misinformation. This study touches upon the fact that jaguars had to reduce their sizes after most of the large Pleistocene prey they relied on went extinct as a survival mechanism. As @GuateGojira correctly pointed out, the small jaguars we see in prey depleted areas of rainforests and deserts represent dwarfed forms.
"Compared with other large, solitary felids, jaguars have an unusual predator to prey body mass ratio. Their accessible prey weight range was 6–60 kg, preferred prey weight range was 45–85 kg, and mean mass of significantly preferred prey was 32 ± 13 kg leading to a predator to prey body mass ratio of 1:0.53, which is much less than that of other solitary felids (although 1:0.84 may be the relationship with the smallest jaguars)."
"These features, coupled with the reduction in jaguar body mass since the Pleistocene, suggest that the loss of larger potential prey items within the preferred and accessible weight ranges at the end-Pleistocene still affects jaguar predatory behavior. It may be that jaguars survived this mass extinction event by preferentially preying on relatively small species."
"The decline in range since the mid-Pleistocene was accompanied by a 15–20% reduction in body mass and a change in limb proportions, such that extant jaguars have shorter metapodials, perhaps as a response to hunting in more closed habitats (Kurten, 1973)."
"Jaguars differ markedly from leopards in being about twice the mass with shorter, more robust limb bones, and relatively wider forepaws that are comparable in relative dimensions to those of lions Panthera leo (Gonyea, 1976; Meachen-Samuels and Van Valkenburgh, 2009b). Across their range, jaguars exhibit up to 100% variation in body mass (Sunquist and Sunquist, 2002) and this is likely to impact their hunting decisions, with the smallest forms being more similar to leopards in the size of their prey. This variability was also reflected in the diet of the populations, with the forest jaguars having a significantly lower mean weight of vertebrate prey at 5.8 kg, compared to 89 kg (including livestock) for floodplain jaguars (Hoogesteijn and Mondolfi, 1996).'
"During the late Pleistocene, there were more than 50 additional species of large (>40 kg) herbivores in the Americas (Kurtén and Anderson, 1980; Greenwood, 2009), and so jaguars evolved in ecosystems with a much higher diversity and availability of potential prey than found today. This is in contrast to Africa, where extant large carnivores prey upon herbivore communities that were similar in abundance, richness and diversity to those which occurred at the end of the Pleistocene (Lyons et al., 2004). This difference likely explains why the predator to prey body mass of jaguars is much smaller than other large solitary felids (Figure 9). For example, jaguars are often considered to be ecologically similar to leopards (Sunquist and Sunquist, 2002), yet jaguars preferentially prey on smaller species than leopards (Figure 9), despite jaguars having a larger body size. )"
"Important jaguar prey species, such as peccaries, spotted paca and nine-banded armadillo are heavily hunted by humans (Redford, 1992; Jorgenson and Redford, 1993). Given the importance of prey in determining predator densities (Fuller and Sievert, 2001; Karanth et al., 2004; Hayward et al., 2007b), reduced prey abundance has been, and probably still is, keeping jaguar populations below densities at which they evolved. Thus we reiterate that the “empty forests syndrome” (Redford, 1992; Wilkie et al., 2011) can have cascading impacts on all trophic levels, including apex predators (Steinmetz et al., 2013)."
Source: https://www.frontiersin.org/articles/10....00148/full
That paper clearly shows how jaguars in many areas outside of floodplain environments have to live on suboptimal prey which is often times too small to support large jaguar populations and at times also have hunting pressure from humans. Jaguars can only dwarf so much before dying to lack of prey, I believe @Dark Jaguar posted on here the case of a very small adult male jaguar from Caatinga which ended up starving to date.
That paper also touches upon what anyone with common sense already knows, that despite having on average similar shoulder heights as leopards or cougars, jaguars can grow to develop twice their body mass and overall larger skeletal structures, because they suffered a reduction on limb size due to dwarfing post-Pleistocene, yet they are still undoubtedly much larger animals.
Leopards for example have had access to large and plentiful ungulate prey in Africa and Asia since the Pleistocene and their sizes have never been comparable to the sizes of modern jaguars who have access to more optimal prey base like the Pantanal. And based on the fossil record we know that the sizes we see today in the Pantanal were the standard sizes of jaguars across their entire range during the Pleistocene, with the largest jaguars being larger than the largest jaguars alive today (with Mesembrina being able to tier with exceptionally large lions or tigers of today at 240+ kgs) . We even know of the existence of a giant subspecies that had previously been confused for the American lion due to its great 200+ kg size: Panthera onca mesembrina.
It's frustrating how much misinformation the same people constantly spend their times spreading on these forums regarding jaguars. If you are a cougar or a leopard fan and you're salty that they don't grow as large as jaguars then you don't actually like those species, you like the fantasy you've created in your head about them. I'm a leopard enthusiast myself but unlike a couple of people from this forum I don't feel the need to degrade jaguars to hype up my favorite cat. In my opinion the mods here could do better with tackling the constant anti-jaguar bias of some people. No wonder other people like Balam and Dark Jaguar have stopped contributing to this forum, it gets frustrating.
04-19-2022, 09:17 PM( This post was last modified: 04-20-2022, 01:17 AM by LonePredator )
(04-19-2022, 01:51 AM)GuateGojira Wrote:
(04-19-2022, 12:23 AM)LonePredator Wrote: What is the biggest prey for a Jaguar other than a Tapir? And what is the largest aquatic prey for Jaguars? Do they hunt large sea turtles?
In the habitat of the jaguar, only the tapir is bigger than him and they live at a low density, the deers are about the same size than jaguar but that is all, wild pigs like pecari and any other wild prey is smaller than the jaguar.
And that is why the document of Hayward et al. (2016) is so interesting because they discuss this dilema, that a large Panthera cat that evolved to kill large prey, now it needs to live on smaller prey and managed to adapt to it very good.
If jaguars had the same wild prey size and density that pumas had in US and Canada (deers of over 200 kg) they will not weigh the 90-100 kg that a puma (if lucky) may reach, but certainly will be a little bigger than the Pantanal jaguars, because they are adapted for that and in the past they weighed over 200 kg during the Pleistocene (P. o. augusta and P. o. messembrina) when the large preys existed in they habitat.
I agree 100%... If that kind of large prey becomes available, the Jaguars would definitely attain a larger size. Maybe about 105-110kg on average since Jaguars are seemingly more capable of hunting 200-250kg prey compared to a Mountain Lion.
And the Panthera is like the royal genus of cats. They conquered every land on earth at some point of time and became apex predators everywhere at some point of time as well (except Australia because these cats did not have ships).
And even to this day, the Tiger, Lion and Jaguar are the apex land predators of their respective continents and are way more successful compared to other predators they live with.
Even the Leopards are so successful and despite being supressed by Lions and Tigers they are still the most widespread big cats and they fill the apex predator spot where the Lions and Tigers are absent.
I think it would be correct to say that Pantheras have been the most successful large cats because when all the other behemoths perished, the Pantheras still adapted and thrived and conquered and even to this day, if it wasn’t for human intervention, Pantheras would probably be living in the same glory as they lived 10,000 years ago.
(04-19-2022, 03:50 AM)Twico5 Wrote: Yes but belizean jaguars are only half the size of pantanal jaguars, and not half the size of amazonian or cerrado jags. They are not dwarfs its just that pantanal jags have a much better prey base.
So what youre saying is that jaguars get bigger (or heavier) with less prey right? Have a look at this ss from this one study conducted in peru:
*This image is copyright of its original author
*This image is copyright of its original author
Rodents made up 58% of puma diets and reptiles made up 33% of jaguar diets followed by other large mammals and large rodents. Pumas were definitely eating smaller prey here. And now for weights of pumas and jags in this area:
*This image is copyright of its original author
*This image is copyright of its original author
“All adults were in good condition. From the track sizes of the captured big cats and the others known on the study area, the average puma and jaguar would each weight about 34kg.” 1 female puma weighed 29kg and 1 female jag weighed 31kg. As i showed you the pumas were eating smaller animals. I thought it would be fair if we compared “dwarf jaguars” to dwarf pumas.
You claimed that jaguars are on a different tier or level. I strongly disagree. In captivity they weigh the same. In places where both cats have similar mean prey weights, they will also weigh around the same. I dont think theres a need to continue this because as i said from the very start i believe it is unfair for us to compare pantanal jags to any population of pumas and as long as you keep on bringing them up i will continue to say this. Pumas can be just as long and just as tall so if a population of jags and pumas are eating the same they WILL have similar body masses wether the jaguar wins in a fight or not.
So now you are going to base your entire statements in TWO jaguar weights from Peru?
And yes, jaguars from Belize are called dwarfs by several people, and not only Pantanal are bigger, also Venezuela jaguars are bigger, even Amazon jaguars are bigger.
And captive animals are irrelevant, they depend of how are rised by humans, in that case even a leopard can be bigger than the biggest jaguar (been incredible fat of course), so I don't see the point on this.
As @Pckts says, I can see from a mille that you are biased in favor of pumas, and trying to discard the Pantanal population shows that. Well, let's check the jaguars from Venezuela, equally larger, no excuses from your part this time. And none of what you showed here proved that pumas weighed the same as jaguars, for the contrary, we showed here that you will need an exceptionaly small jaguar population to compare it with a similar sized population of pumas (with better prey base) to reach them at the same size.
Even when they have the same average prey base, you completelly ignored with I told you, you also need to know the frecuency of hunting, a puma killing a large deer every 4 days will eat more than a jaguar eating an armadillo per day.
Again, your same images showed that even when the puma can be as long and tall as a jaguar, there are not even near to the same body mass, robustness and skull size. Jaguars are another tier, that is for sure and even with similar prey base, jaguar always are bigger, there is no discussion here. No expert is going to tell you something else.
I am not basing all of my statements off of two weights obviously because if I was then I would’ve started this convo by posting them. Do you have proof that belizean Jaguars are dwarfs? Maybe in a paper or something?
Captive weights are relevant because if a puma and a jaguar are both eating the same but are the same size then this would mean that neither is larger simply because they have “different body plans” as you said. Jaguars are not on another tier, they are simply really heavy when they have a lot of things to hunt.
6kg mean prey weight for forested regions vs 110kg mean prey weight for the pantanal region. That is a huge difference. But even the armadillo-eating jags look bulky and healthy. They don’t die of starvation or look malnourished.
*This image is copyright of its original author
In this study from pench NP the average weight of animals consumed by tigers was 82kg. Pench tigers don’t look unhealthy to me and even though this is a really low average prey weight for a tiger population pench tigers are still able to be bulky and large. Except there is a jaguar population that has a higher mean prey weight than these tigers. Stomach contents from Venezuela showed an average weight of 50kg for all prey including domestic and 32kg for wild prey exclusively.
*This image is copyright of its original author
*This image is copyright of its original author
It is the prey base of the population that influences their size. Yes, I totally agree with you. 113kg and 34kg are a big difference in mean prey weight. Given how Jaguars (dwarf Jaguars ofc!) can still be healthy and bulky with an average prey weight of 5kg, pantanal Jaguars as well as Venezuelan Jaguars owe their abnormal size to their prey base.
Let me ask you, why are Jaguars and pumas in nw mexico the same size? I believe you or Pckts said earlier that Jaguars are badly adapted to desert environments, which is true. Body mass however would only be affected by food consumption and not simply by the environment. Let’s see what Jaguars are pumas are eating in Sonora, Mexico!
*This image is copyright of its original author
*This image is copyright of its original author
Woah! So Jaguars are eating better than pumas in mexico. They are scavenging on kills (likely kills of both other jags and pumas), killing calves, white-tailed deer, and peccary. Pumas are scavenging less, killing calves less and that too the calves they kill are smaller.
Jaguars are not on another tier, period. I have posted countless studies these past few days here comparing the diets, prey bases and body masses of pumas and jags but none of that seems to have made a difference and you claim that Jaguars are on another tier still. This idea is one that is pushed by your bias towards Jaguars, and not by factual evidence of any sort.
Quote:“All adults were in good condition. From the track sizes of the captured big cats and the others known on the study area, the average puma and jaguar would each weight about 34kg.” 1 female puma weighed 29kg and 1 female jag weighed 31kg. As i showed you the pumas were eating smaller animals. I thought it would be fair if we compared “dwarf jaguars” to dwarf pumas.
You post these studies but don't seem to actually read the details.
Track size has nothing to do with verifiable weight, it's one of many tools to estimate a weight and not even one of the best correlating tools used.
Next is that neither of the 2 big cats actually stayed in this territory year round and between the two of them, it was the Jaguar who roared, scratched marked more intensely and displayed general territorial characteristics for more than the Pumas. On top that, the Jaguar is the one preying on larger mammals like the Peccary as well as dominating the river banks where the best prey congregates.
Lastly and most importantly, this study is from 40 years ago and is very minimal in details, they just didn't have much at their disposal.
file:///C:/Users/Jared/Downloads/Emmons1987BESFelidFeeding.pdf
But like all other locations these two cats share habitat, it's the Jaguar that dominates.
.
Quote:In captivity they weigh the same. In places where both cats have similar mean prey weights, they will also weigh around the same.
Where are you getting this?
In captivity they absolutely don't weigh the same. I can show you numerous captive 100kg + Jaguars that are in good shape while I don't know of a single Cougar in captivity that's reached that weight, at least without being obese.
And in the wild, the only place they may be the similar size is the Caatinga
Quote:But even the armadillo-eating jags look bulky and healthy. They don’t die of starvation or look malnourished.
Literally in that post on Caatinga Jaguars mentioned, they discuss their Armadillo diet and one of their study Jaguars dying of starvation.
Quote:In this study from pench NP the average weight of animals consumed by tigers was 82kg. Pench tigers don’t look unhealthy to me and even though this is a really low average prey weight for a tiger population pench tigers are still able to be bulky and large. Except there is a jaguar population that has a higher mean prey weight than these tigers. Stomach contents from Venezuela showed an average weight of 50kg for all prey including domestic and 32kg for wild prey exclusively.
You're grasping at straws.
Prey studies, especially based off of scat samples offer no real idea of prey size. They estimated based off of limited information.
Quote:Given how Jaguars (dwarf Jaguars ofc!) can still be healthy and bulky with an average prey weight of 5kg, pantanal Jaguars as well as Venezuelan Jaguars owe their abnormal size to their prey base.
Again I steer you back to the post on Caatinga Jaguars and the studies mentioned in within it
Quote:Woah! So Jaguars are eating better than pumas in mexico. They are scavenging on kills (likely kills of both other jags and pumas), killing calves, white-tailed deer, and peccary. Pumas are scavenging less, killing calves less and that too the calves they kill are smaller.
You know why Jaguars eat larger prey?
Because they are more powerful, what is there to discuss?
Quote:Jaguars are not on another tier, period. I have posted countless studies these past few days here comparing the diets, prey bases and body masses of pumas and jags but none of that seems to have made a difference and you claim that Jaguars are on another tier still. This idea is one that is pushed by your bias towards Jaguars, and not by factual evidence of any sort.
Of course they are, Jaguars are the dominate cat over Pumas anywhere they coexist. They grow larger in size, control the best hunting areas and eat the largest, most desirable prey.
You've literally been shown this time and time again on top of misquoting studies that you thought backed you for some reason only to have been shown that they didn't.
Lastly and most telling is that the only places where both coexist and are close in size are places where Jaguars and their prey have been hunted to near extinction, this isn't a fair comparison since Pumas are more capable to prey on smaller, fast moving animals while Jaguars specifically show shrinkage in size when doing so as well as having unhealthy population numbers and even starving to death.
(04-19-2022, 03:50 AM)Twico5 Wrote: Pumas can be just as long and just as tall so if a population of jags and pumas are eating the same they WILL have similar body masses wether the jaguar wins in a fight or not.
This part summarize everithing.
Your studies itself showed that even at the same prey base, pumas do not weight the same as jaguars, they are two completelly different body plans for cats, they are morphologically distinct and also they have different body needs and metabolism. But the last part, the part of "win in a fight" is what shows that these entire debate is futile. We DON'T discuss "vs" issues, specially between especies that are very well know and that we know that there is a dominance/coexistance/avoidance relation depending of the area that normally favors the jaguar, there is no doubt.
I don't care who win in this fight, I just want o show that your assumptions are incorrect and that you are trying to prove something that do not exist, and you have several posters telling you the same thing.
(04-19-2022, 03:50 AM)Twico5 Wrote: You claimed that jaguars are on a different tier or level. I strongly disagree. In captivity they weigh the same. In places where both cats have similar mean prey weights, they will also weigh around the same. I dont think theres a need to continue this because as i said from the very start i believe it is unfair for us to compare pantanal jags to any population of pumas and as long as you keep on bringing them up i will continue to say this. Pumas can be just as long and just as tall so if a population of jags and pumas are eating the same they WILL have similar body masses wether the jaguar wins in a fight or not.
I suggest everyone to stop mention this "winning a fight" topic, we are on wildfact and we don't want discussions here to turn into VS debates at Carnivora trash forum level.
Regarding the rest, the idea that jaguars and cougars grow to the same size with the same food input is so wrong but nothing will stop the anti-jaguar crowd from spreading their misinformation. This study touches upon the fact that jaguars had to reduce their sizes after most of the large Pleistocene prey they relied on went extinct as a survival mechanism. As @GuateGojira correctly pointed out, the small jaguars we see in prey depleted areas of rainforests and deserts represent dwarfed forms.
"Compared with other large, solitary felids, jaguars have an unusual predator to prey body mass ratio. Their accessible prey weight range was 6–60 kg, preferred prey weight range was 45–85 kg, and mean mass of significantly preferred prey was 32 ± 13 kg leading to a predator to prey body mass ratio of 1:0.53, which is much less than that of other solitary felids (although 1:0.84 may be the relationship with the smallest jaguars)."
"These features, coupled with the reduction in jaguar body mass since the Pleistocene, suggest that the loss of larger potential prey items within the preferred and accessible weight ranges at the end-Pleistocene still affects jaguar predatory behavior. It may be that jaguars survived this mass extinction event by preferentially preying on relatively small species."
"The decline in range since the mid-Pleistocene was accompanied by a 15–20% reduction in body mass and a change in limb proportions, such that extant jaguars have shorter metapodials, perhaps as a response to hunting in more closed habitats (Kurten, 1973)."
"Jaguars differ markedly from leopards in being about twice the mass with shorter, more robust limb bones, and relatively wider forepaws that are comparable in relative dimensions to those of lions Panthera leo (Gonyea, 1976; Meachen-Samuels and Van Valkenburgh, 2009b). Across their range, jaguars exhibit up to 100% variation in body mass (Sunquist and Sunquist, 2002) and this is likely to impact their hunting decisions, with the smallest forms being more similar to leopards in the size of their prey. This variability was also reflected in the diet of the populations, with the forest jaguars having a significantly lower mean weight of vertebrate prey at 5.8 kg, compared to 89 kg (including livestock) for floodplain jaguars (Hoogesteijn and Mondolfi, 1996).'
"During the late Pleistocene, there were more than 50 additional species of large (>40 kg) herbivores in the Americas (Kurtén and Anderson, 1980; Greenwood, 2009), and so jaguars evolved in ecosystems with a much higher diversity and availability of potential prey than found today. This is in contrast to Africa, where extant large carnivores prey upon herbivore communities that were similar in abundance, richness and diversity to those which occurred at the end of the Pleistocene (Lyons et al., 2004). This difference likely explains why the predator to prey body mass of jaguars is much smaller than other large solitary felids (Figure 9). For example, jaguars are often considered to be ecologically similar to leopards (Sunquist and Sunquist, 2002), yet jaguars preferentially prey on smaller species than leopards (Figure 9), despite jaguars having a larger body size. )"
"Important jaguar prey species, such as peccaries, spotted paca and nine-banded armadillo are heavily hunted by humans (Redford, 1992; Jorgenson and Redford, 1993). Given the importance of prey in determining predator densities (Fuller and Sievert, 2001; Karanth et al., 2004; Hayward et al., 2007b), reduced prey abundance has been, and probably still is, keeping jaguar populations below densities at which they evolved. Thus we reiterate that the “empty forests syndrome” (Redford, 1992; Wilkie et al., 2011) can have cascading impacts on all trophic levels, including apex predators (Steinmetz et al., 2013)."
Source: https://www.frontiersin.org/articles/10....00148/full
That paper clearly shows how jaguars in many areas outside of floodplain environments have to live on suboptimal prey which is often times too small to support large jaguar populations and at times also have hunting pressure from humans. Jaguars can only dwarf so much before dying to lack of prey, I believe @Dark Jaguar posted on here the case of a very small adult male jaguar from Caatinga which ended up starving to date.
That paper also touches upon what anyone with common sense already knows, that despite having on average similar shoulder heights as leopards or cougars, jaguars can grow to develop twice their body mass and overall larger skeletal structures, because they suffered a reduction on limb size due to dwarfing post-Pleistocene, yet they are still undoubtedly much larger animals.
Leopards for example have had access to large and plentiful ungulate prey in Africa and Asia since the Pleistocene and their sizes have never been comparable to the sizes of modern jaguars who have access to more optimal prey base like the Pantanal. And based on the fossil record we know that the sizes we see today in the Pantanal were the standard sizes of jaguars across their entire range during the Pleistocene, with the largest jaguars being larger than the largest jaguars alive today (with Mesembrina being able to tier with exceptionally large lions or tigers of today at 240+ kgs) . We even know of the existence of a giant subspecies that had previously been confused for the American lion due to its great 200+ kg size: Panthera onca mesembrina.
It's frustrating how much misinformation the same people constantly spend their times spreading on these forums regarding jaguars. If you are a cougar or a leopard fan and you're salty that they don't grow as large as jaguars then you don't actually like those species, you like the fantasy you've created in your head about them. I'm a leopard enthusiast myself but unlike a couple of people from this forum I don't feel the need to degrade jaguars to hype up my favorite cat. In my opinion the mods here could do better with tackling the constant anti-jaguar bias of some people. No wonder other people like Balam and Dark Jaguar have stopped contributing to this forum, it gets frustrating.
I am not mindlessly spreading misinfo about Jaguars. I’ve been posting studies to prove my points.
“Their accessible prey weight range was 6–60 kg, preferred prey weight range was 45–85 kg, and mean mass of significantly preferred prey was 32 ± 13 kg leading to a predator to prey body mass ratio of 1:0.53, which is much less than that of other solitary felids (although 1:0.84 may be the relationship with the smallest jaguars)." Ok. You do realize that pantanal Jaguars have a predator to prey body mass ratio of like 1:1 right? This is one of the many points that I posted evidence for.
Just because you think that Pleistocene jags got to 240kg doesn’t mean it’s wrong to discuss or compare puma and jaguar sizes. I don’t care if jaguars are 240kg giant tiger sized cats that shrunk because their prey died out because this discussion is not about them, it was always about modern jaguars and modern pumas.
There is nothing wrong with comparing the sizes of ANY two animals wether it be jaguar and puma or leopard and tiger as long as I’m at least using studies and valid evidence as proof for my claims and as long as I’m not mindlessly saying things I believe to be true. It seems to me that this only wrong, not because I’m not debating properly or because I’m not posting evidence but rather because this is a comparison between PUMA and jaguar. I don’t have an anti-jaguar bias, this is clear by the opinions I’ve given on how a fight would go between these two cats. Please read the screenshots and papers I include in my posts instead of calling me anti-jaguar
(04-19-2022, 03:50 AM)Twico5 Wrote: You claimed that jaguars are on a different tier or level. I strongly disagree. In captivity they weigh the same. In places where both cats have similar mean prey weights, they will also weigh around the same. I dont think theres a need to continue this because as i said from the very start i believe it is unfair for us to compare pantanal jags to any population of pumas and as long as you keep on bringing them up i will continue to say this. Pumas can be just as long and just as tall so if a population of jags and pumas are eating the same they WILL have similar body masses wether the jaguar wins in a fight or not.
I suggest everyone to stop mention this "winning a fight" topic, we are on wildfact and we don't want discussions here to turn into VS debates at Carnivora trash forum level.
Regarding the rest, the idea that jaguars and cougars grow to the same size with the same food input is so wrong but nothing will stop the anti-jaguar crowd from spreading their misinformation. This study touches upon the fact that jaguars had to reduce their sizes after most of the large Pleistocene prey they relied on went extinct as a survival mechanism. As @GuateGojira correctly pointed out, the small jaguars we see in prey depleted areas of rainforests and deserts represent dwarfed forms.
"Compared with other large, solitary felids, jaguars have an unusual predator to prey body mass ratio. Their accessible prey weight range was 6–60 kg, preferred prey weight range was 45–85 kg, and mean mass of significantly preferred prey was 32 ± 13 kg leading to a predator to prey body mass ratio of 1:0.53, which is much less than that of other solitary felids (although 1:0.84 may be the relationship with the smallest jaguars)."
"These features, coupled with the reduction in jaguar body mass since the Pleistocene, suggest that the loss of larger potential prey items within the preferred and accessible weight ranges at the end-Pleistocene still affects jaguar predatory behavior. It may be that jaguars survived this mass extinction event by preferentially preying on relatively small species."
"The decline in range since the mid-Pleistocene was accompanied by a 15–20% reduction in body mass and a change in limb proportions, such that extant jaguars have shorter metapodials, perhaps as a response to hunting in more closed habitats (Kurten, 1973)."
"Jaguars differ markedly from leopards in being about twice the mass with shorter, more robust limb bones, and relatively wider forepaws that are comparable in relative dimensions to those of lions Panthera leo (Gonyea, 1976; Meachen-Samuels and Van Valkenburgh, 2009b). Across their range, jaguars exhibit up to 100% variation in body mass (Sunquist and Sunquist, 2002) and this is likely to impact their hunting decisions, with the smallest forms being more similar to leopards in the size of their prey. This variability was also reflected in the diet of the populations, with the forest jaguars having a significantly lower mean weight of vertebrate prey at 5.8 kg, compared to 89 kg (including livestock) for floodplain jaguars (Hoogesteijn and Mondolfi, 1996).'
"During the late Pleistocene, there were more than 50 additional species of large (>40 kg) herbivores in the Americas (Kurtén and Anderson, 1980; Greenwood, 2009), and so jaguars evolved in ecosystems with a much higher diversity and availability of potential prey than found today. This is in contrast to Africa, where extant large carnivores prey upon herbivore communities that were similar in abundance, richness and diversity to those which occurred at the end of the Pleistocene (Lyons et al., 2004). This difference likely explains why the predator to prey body mass of jaguars is much smaller than other large solitary felids (Figure 9). For example, jaguars are often considered to be ecologically similar to leopards (Sunquist and Sunquist, 2002), yet jaguars preferentially prey on smaller species than leopards (Figure 9), despite jaguars having a larger body size. )"
"Important jaguar prey species, such as peccaries, spotted paca and nine-banded armadillo are heavily hunted by humans (Redford, 1992; Jorgenson and Redford, 1993). Given the importance of prey in determining predator densities (Fuller and Sievert, 2001; Karanth et al., 2004; Hayward et al., 2007b), reduced prey abundance has been, and probably still is, keeping jaguar populations below densities at which they evolved. Thus we reiterate that the “empty forests syndrome” (Redford, 1992; Wilkie et al., 2011) can have cascading impacts on all trophic levels, including apex predators (Steinmetz et al., 2013)."
Source: https://www.frontiersin.org/articles/10....00148/full
That paper clearly shows how jaguars in many areas outside of floodplain environments have to live on suboptimal prey which is often times too small to support large jaguar populations and at times also have hunting pressure from humans. Jaguars can only dwarf so much before dying to lack of prey, I believe @Dark Jaguar posted on here the case of a very small adult male jaguar from Caatinga which ended up starving to date.
That paper also touches upon what anyone with common sense already knows, that despite having on average similar shoulder heights as leopards or cougars, jaguars can grow to develop twice their body mass and overall larger skeletal structures, because they suffered a reduction on limb size due to dwarfing post-Pleistocene, yet they are still undoubtedly much larger animals.
Leopards for example have had access to large and plentiful ungulate prey in Africa and Asia since the Pleistocene and their sizes have never been comparable to the sizes of modern jaguars who have access to more optimal prey base like the Pantanal. And based on the fossil record we know that the sizes we see today in the Pantanal were the standard sizes of jaguars across their entire range during the Pleistocene, with the largest jaguars being larger than the largest jaguars alive today (with Mesembrina being able to tier with exceptionally large lions or tigers of today at 240+ kgs) . We even know of the existence of a giant subspecies that had previously been confused for the American lion due to its great 200+ kg size: Panthera onca mesembrina.
It's frustrating how much misinformation the same people constantly spend their times spreading on these forums regarding jaguars. If you are a cougar or a leopard fan and you're salty that they don't grow as large as jaguars then you don't actually like those species, you like the fantasy you've created in your head about them. I'm a leopard enthusiast myself but unlike a couple of people from this forum I don't feel the need to degrade jaguars to hype up my favorite cat. In my opinion the mods here could do better with tackling the constant anti-jaguar bias of some people. No wonder other people like Balam and Dark Jaguar have stopped contributing to this forum, it gets frustrating.
I am not mindlessly spreading misinfo about Jaguars. I’ve been posting studies to prove my points.
“Their accessible prey weight range was 6–60 kg, preferred prey weight range was 45–85 kg, and mean mass of significantly preferred prey was 32 ± 13 kg leading to a predator to prey body mass ratio of 1:0.53, which is much less than that of other solitary felids (although 1:0.84 may be the relationship with the smallest jaguars)." Ok. You do realize that pantanal Jaguars have a predator to prey body mass ratio of like 1:1 right? This is one of the many points that I posted evidence for.
Just because you think that Pleistocene jags got to 240kg doesn’t mean it’s wrong to discuss or compare puma and jaguar sizes. I don’t care if jaguars are 240kg giant tiger sized cats that shrunk because their prey died out because this discussion is not about them, it was always about modern jaguars and modern pumas.
There is nothing wrong with comparing the sizes of ANY two animals wether it be jaguar and puma or leopard and tiger as long as I’m at least using studies and valid evidence as proof for my claims and as long as I’m not mindlessly saying things I believe to be true. It seems to me that this only wrong, not because I’m not debating properly or because I’m not posting evidence but rather because this is a comparison between PUMA and jaguar. I don’t have an anti-jaguar bias, this is clear by the opinions I’ve given on how a fight would go between these two cats. Please read the screenshots and papers I include in my posts instead of calling me anti-jaguar
What are you even trying to prove though? Are you claiming that Cougars are bigger than Jaguars? Or are you trying to claim that Cougars would be bigger in a this or that hypothetical scenario?
(04-19-2022, 03:50 AM)Twico5 Wrote: Yes but belizean jaguars are only half the size of pantanal jaguars, and not half the size of amazonian or cerrado jags. They are not dwarfs its just that pantanal jags have a much better prey base.
So what youre saying is that jaguars get bigger (or heavier) with less prey right? Have a look at this ss from this one study conducted in peru:
*This image is copyright of its original author
*This image is copyright of its original author
Rodents made up 58% of puma diets and reptiles made up 33% of jaguar diets followed by other large mammals and large rodents. Pumas were definitely eating smaller prey here. And now for weights of pumas and jags in this area:
*This image is copyright of its original author
*This image is copyright of its original author
“All adults were in good condition. From the track sizes of the captured big cats and the others known on the study area, the average puma and jaguar would each weight about 34kg.” 1 female puma weighed 29kg and 1 female jag weighed 31kg. As i showed you the pumas were eating smaller animals. I thought it would be fair if we compared “dwarf jaguars” to dwarf pumas.
You claimed that jaguars are on a different tier or level. I strongly disagree. In captivity they weigh the same. In places where both cats have similar mean prey weights, they will also weigh around the same. I dont think theres a need to continue this because as i said from the very start i believe it is unfair for us to compare pantanal jags to any population of pumas and as long as you keep on bringing them up i will continue to say this. Pumas can be just as long and just as tall so if a population of jags and pumas are eating the same they WILL have similar body masses wether the jaguar wins in a fight or not.
So now you are going to base your entire statements in TWO jaguar weights from Peru?
And yes, jaguars from Belize are called dwarfs by several people, and not only Pantanal are bigger, also Venezuela jaguars are bigger, even Amazon jaguars are bigger.
And captive animals are irrelevant, they depend of how are rised by humans, in that case even a leopard can be bigger than the biggest jaguar (been incredible fat of course), so I don't see the point on this.
As @Pckts says, I can see from a mille that you are biased in favor of pumas, and trying to discard the Pantanal population shows that. Well, let's check the jaguars from Venezuela, equally larger, no excuses from your part this time. And none of what you showed here proved that pumas weighed the same as jaguars, for the contrary, we showed here that you will need an exceptionaly small jaguar population to compare it with a similar sized population of pumas (with better prey base) to reach them at the same size.
Even when they have the same average prey base, you completelly ignored with I told you, you also need to know the frecuency of hunting, a puma killing a large deer every 4 days will eat more than a jaguar eating an armadillo per day.
Again, your same images showed that even when the puma can be as long and tall as a jaguar, there are not even near to the same body mass, robustness and skull size. Jaguars are another tier, that is for sure and even with similar prey base, jaguar always are bigger, there is no discussion here. No expert is going to tell you something else.
I am not basing all of my statements off of two weights obviously because if I was then I would’ve started this convo by posting them. Do you have proof that belizean Jaguars are dwarfs? Maybe in a paper or something?
Captive weights are relevant because if a puma and a jaguar are both eating the same but are the same size then this would mean that neither is larger simply because they have “different body plans” as you said. Jaguars are not on another tier, they are simply really heavy when they have a lot of things to hunt.
6kg mean prey weight for forested regions vs 110kg mean prey weight for the pantanal region. That is a huge difference. But even the armadillo-eating jags look bulky and healthy. They don’t die of starvation or look malnourished.
*This image is copyright of its original author
In this study from pench NP the average weight of animals consumed by tigers was 82kg. Pench tigers don’t look unhealthy to me and even though this is a really low average prey weight for a tiger population pench tigers are still able to be bulky and large. Except there is a jaguar population that has a higher mean prey weight than these tigers. Stomach contents from Venezuela showed an average weight of 50kg for all prey including domestic and 32kg for wild prey exclusively.
*This image is copyright of its original author
*This image is copyright of its original author
It is the prey base of the population that influences their size. Yes, I totally agree with you. 113kg and 34kg are a big difference in mean prey weight. Given how Jaguars (dwarf Jaguars ofc!) can still be healthy and bulky with an average prey weight of 5kg, pantanal Jaguars as well as Venezuelan Jaguars owe their abnormal size to their prey base.
Let me ask you, why are Jaguars and pumas in nw mexico the same size? I believe you or Pckts said earlier that Jaguars are badly adapted to desert environments, which is true. Body mass however would only be affected by food consumption and not simply by the environment. Let’s see what Jaguars are pumas are eating in Sonora, Mexico!
*This image is copyright of its original author
*This image is copyright of its original author
Woah! So Jaguars are eating better than pumas in mexico. They are scavenging on kills (likely kills of both other jags and pumas), killing calves, white-tailed deer, and peccary. Pumas are scavenging less, killing calves less and that too the calves they kill are smaller.
Jaguars are not on another tier, period. I have posted countless studies these past few days here comparing the diets, prey bases and body masses of pumas and jags but none of that seems to have made a difference and you claim that Jaguars are on another tier still. This idea is one that is pushed by your bias towards Jaguars, and not by factual evidence of any sort.
Quote:“All adults were in good condition. From the track sizes of the captured big cats and the others known on the study area, the average puma and jaguar would each weight about 34kg.” 1 female puma weighed 29kg and 1 female jag weighed 31kg. As i showed you the pumas were eating smaller animals. I thought it would be fair if we compared “dwarf jaguars” to dwarf pumas.
You post these studies but don't seem to actually read the details.
Track size has nothing to do with verifiable weight, it's one of many tools to estimate a weight and not even one of the best correlating tools used.
Next is that neither of the 2 big cats actually stayed in this territory year round and between the two of them, it was the Jaguar who roared, scratched marked more intensely and displayed general territorial characteristics for more than the Pumas. On top that, the Jaguar is the one preying on larger mammals like the Peccary as well as dominating the river banks where the best prey congregates.
Lastly and most importantly, this study is from 40 years ago and is very minimal in details, they just didn't have much at their disposal.
file:///C:/Users/Jared/Downloads/Emmons1987BESFelidFeeding.pdf
But like all other locations these two cats share habitat, it's the Jaguar that dominates.
.
Quote:In captivity they weigh the same. In places where both cats have similar mean prey weights, they will also weigh around the same.
Where are you getting this?
In captivity they absolutely don't weigh the same. I can show you numerous captive 100kg + Jaguars that are in good shape while I don't know of a single Cougar in captivity that's reached that weight, at least without being obese.
And in the wild, the only place they may be the similar size is the Caatinga
Quote:But even the armadillo-eating jags look bulky and healthy. They don’t die of starvation or look malnourished.
Literally in that post on Caatinga Jaguars mentioned, they discuss their Armadillo diet and one of their study Jaguars dying of starvation.
Quote:In this study from pench NP the average weight of animals consumed by tigers was 82kg. Pench tigers don’t look unhealthy to me and even though this is a really low average prey weight for a tiger population pench tigers are still able to be bulky and large. Except there is a jaguar population that has a higher mean prey weight than these tigers. Stomach contents from Venezuela showed an average weight of 50kg for all prey including domestic and 32kg for wild prey exclusively.
You're grasping at straws.
Prey studies, especially based off of scat samples offer no real idea of prey size. They estimated based off of limited information.
Quote:Given how Jaguars (dwarf Jaguars ofc!) can still be healthy and bulky with an average prey weight of 5kg, pantanal Jaguars as well as Venezuelan Jaguars owe their abnormal size to their prey base.
Again I steer you back to the post on Caatinga Jaguars and the studies mentioned in within it
Quote:Woah! So Jaguars are eating better than pumas in mexico. They are scavenging on kills (likely kills of both other jags and pumas), killing calves, white-tailed deer, and peccary. Pumas are scavenging less, killing calves less and that too the calves they kill are smaller.
You know why Jaguars eat larger prey?
Because they are more powerful, what is there to discuss?
Quote:Jaguars are not on another tier, period. I have posted countless studies these past few days here comparing the diets, prey bases and body masses of pumas and jags but none of that seems to have made a difference and you claim that Jaguars are on another tier still. This idea is one that is pushed by your bias towards Jaguars, and not by factual evidence of any sort.
Of course they are, Jaguars are the dominate cat over Pumas anywhere they coexist. They grow larger in size, control the best hunting areas and eat the largest, most desirable prey.
You've literally been shown this time and time again on top of misquoting studies that you thought backed you for some reason only to have been shown that they didn't.
Lastly and most telling is that the only places where both coexist and are close in size are places where Jaguars and their prey have been hunted to near extinction, this isn't a fair comparison since Pumas are more capable to prey on smaller, fast moving animals while Jaguars specifically show shrinkage in size when doing so as well as having unhealthy population numbers and even starving to death.
I never mentioned caatinga jags a single time in that post. Guate called Costa Rican and Mexican Jaguars “dwarf jaguars” despite the fact that they are feeding on chelonians which are pretty much free kills for obvious reasons and calves in nw Mexico. They have enough food they just don’t have a ~90:113 predator mass to mean prey mass ratio like pantanal jags or millions of caiman and etc etc. Pumas are more capable to prey on smaller, fast moving animals? In the screenshot I posted from the diet study white-tailed deer accounted for 24% of Jaguar diets. It also says there how the calves that jaguars killed averaged 90kg while the calves that pumas killed averaged 50kg. So these jags were killing animals twice their size and scavenging more than pumas.
The study I posted that had the weights of a female puma and jaguaress also included the weight of a male jaguar (37kg). They weren’t making rough estimates of the sizes of these cats. “From the track sizes of the captured big cats and the others known on the study area”. They captured several jaguars and pumas, measured their paws and weighed them then compared the measurements of the tracks they found to the track sizes of the cats that they weighed.
(04-19-2022, 03:50 AM)Twico5 Wrote: You claimed that jaguars are on a different tier or level. I strongly disagree. In captivity they weigh the same. In places where both cats have similar mean prey weights, they will also weigh around the same. I dont think theres a need to continue this because as i said from the very start i believe it is unfair for us to compare pantanal jags to any population of pumas and as long as you keep on bringing them up i will continue to say this. Pumas can be just as long and just as tall so if a population of jags and pumas are eating the same they WILL have similar body masses wether the jaguar wins in a fight or not.
I suggest everyone to stop mention this "winning a fight" topic, we are on wildfact and we don't want discussions here to turn into VS debates at Carnivora trash forum level.
Regarding the rest, the idea that jaguars and cougars grow to the same size with the same food input is so wrong but nothing will stop the anti-jaguar crowd from spreading their misinformation. This study touches upon the fact that jaguars had to reduce their sizes after most of the large Pleistocene prey they relied on went extinct as a survival mechanism. As @GuateGojira correctly pointed out, the small jaguars we see in prey depleted areas of rainforests and deserts represent dwarfed forms.
"Compared with other large, solitary felids, jaguars have an unusual predator to prey body mass ratio. Their accessible prey weight range was 6–60 kg, preferred prey weight range was 45–85 kg, and mean mass of significantly preferred prey was 32 ± 13 kg leading to a predator to prey body mass ratio of 1:0.53, which is much less than that of other solitary felids (although 1:0.84 may be the relationship with the smallest jaguars)."
"These features, coupled with the reduction in jaguar body mass since the Pleistocene, suggest that the loss of larger potential prey items within the preferred and accessible weight ranges at the end-Pleistocene still affects jaguar predatory behavior. It may be that jaguars survived this mass extinction event by preferentially preying on relatively small species."
"The decline in range since the mid-Pleistocene was accompanied by a 15–20% reduction in body mass and a change in limb proportions, such that extant jaguars have shorter metapodials, perhaps as a response to hunting in more closed habitats (Kurten, 1973)."
"Jaguars differ markedly from leopards in being about twice the mass with shorter, more robust limb bones, and relatively wider forepaws that are comparable in relative dimensions to those of lions Panthera leo (Gonyea, 1976; Meachen-Samuels and Van Valkenburgh, 2009b). Across their range, jaguars exhibit up to 100% variation in body mass (Sunquist and Sunquist, 2002) and this is likely to impact their hunting decisions, with the smallest forms being more similar to leopards in the size of their prey. This variability was also reflected in the diet of the populations, with the forest jaguars having a significantly lower mean weight of vertebrate prey at 5.8 kg, compared to 89 kg (including livestock) for floodplain jaguars (Hoogesteijn and Mondolfi, 1996).'
"During the late Pleistocene, there were more than 50 additional species of large (>40 kg) herbivores in the Americas (Kurtén and Anderson, 1980; Greenwood, 2009), and so jaguars evolved in ecosystems with a much higher diversity and availability of potential prey than found today. This is in contrast to Africa, where extant large carnivores prey upon herbivore communities that were similar in abundance, richness and diversity to those which occurred at the end of the Pleistocene (Lyons et al., 2004). This difference likely explains why the predator to prey body mass of jaguars is much smaller than other large solitary felids (Figure 9). For example, jaguars are often considered to be ecologically similar to leopards (Sunquist and Sunquist, 2002), yet jaguars preferentially prey on smaller species than leopards (Figure 9), despite jaguars having a larger body size. )"
"Important jaguar prey species, such as peccaries, spotted paca and nine-banded armadillo are heavily hunted by humans (Redford, 1992; Jorgenson and Redford, 1993). Given the importance of prey in determining predator densities (Fuller and Sievert, 2001; Karanth et al., 2004; Hayward et al., 2007b), reduced prey abundance has been, and probably still is, keeping jaguar populations below densities at which they evolved. Thus we reiterate that the “empty forests syndrome” (Redford, 1992; Wilkie et al., 2011) can have cascading impacts on all trophic levels, including apex predators (Steinmetz et al., 2013)."
Source: https://www.frontiersin.org/articles/10....00148/full
That paper clearly shows how jaguars in many areas outside of floodplain environments have to live on suboptimal prey which is often times too small to support large jaguar populations and at times also have hunting pressure from humans. Jaguars can only dwarf so much before dying to lack of prey, I believe @Dark Jaguar posted on here the case of a very small adult male jaguar from Caatinga which ended up starving to date.
That paper also touches upon what anyone with common sense already knows, that despite having on average similar shoulder heights as leopards or cougars, jaguars can grow to develop twice their body mass and overall larger skeletal structures, because they suffered a reduction on limb size due to dwarfing post-Pleistocene, yet they are still undoubtedly much larger animals.
Leopards for example have had access to large and plentiful ungulate prey in Africa and Asia since the Pleistocene and their sizes have never been comparable to the sizes of modern jaguars who have access to more optimal prey base like the Pantanal. And based on the fossil record we know that the sizes we see today in the Pantanal were the standard sizes of jaguars across their entire range during the Pleistocene, with the largest jaguars being larger than the largest jaguars alive today (with Mesembrina being able to tier with exceptionally large lions or tigers of today at 240+ kgs) . We even know of the existence of a giant subspecies that had previously been confused for the American lion due to its great 200+ kg size: Panthera onca mesembrina.
It's frustrating how much misinformation the same people constantly spend their times spreading on these forums regarding jaguars. If you are a cougar or a leopard fan and you're salty that they don't grow as large as jaguars then you don't actually like those species, you like the fantasy you've created in your head about them. I'm a leopard enthusiast myself but unlike a couple of people from this forum I don't feel the need to degrade jaguars to hype up my favorite cat. In my opinion the mods here could do better with tackling the constant anti-jaguar bias of some people. No wonder other people like Balam and Dark Jaguar have stopped contributing to this forum, it gets frustrating.
I am not mindlessly spreading misinfo about Jaguars. I’ve been posting studies to prove my points.
“Their accessible prey weight range was 6–60 kg, preferred prey weight range was 45–85 kg, and mean mass of significantly preferred prey was 32 ± 13 kg leading to a predator to prey body mass ratio of 1:0.53, which is much less than that of other solitary felids (although 1:0.84 may be the relationship with the smallest jaguars)." Ok. You do realize that pantanal Jaguars have a predator to prey body mass ratio of like 1:1 right? This is one of the many points that I posted evidence for.
Just because you think that Pleistocene jags got to 240kg doesn’t mean it’s wrong to discuss or compare puma and jaguar sizes. I don’t care if jaguars are 240kg giant tiger sized cats that shrunk because their prey died out because this discussion is not about them, it was always about modern jaguars and modern pumas.
There is nothing wrong with comparing the sizes of ANY two animals wether it be jaguar and puma or leopard and tiger as long as I’m at least using studies and valid evidence as proof for my claims and as long as I’m not mindlessly saying things I believe to be true. It seems to me that this only wrong, not because I’m not debating properly or because I’m not posting evidence but rather because this is a comparison between PUMA and jaguar. I don’t have an anti-jaguar bias, this is clear by the opinions I’ve given on how a fight would go between these two cats. Please read the screenshots and papers I include in my posts instead of calling me anti-jaguar
What are you even trying to prove though? Are you claiming that Cougars are bigger than Jaguars? Or are you trying to claim that Cougars would be bigger in a this or that hypothetical scenario?
Jaguars don’t weigh significantly more than pumas under the same circumstances and with the same diet.
04-20-2022, 03:10 AM( This post was last modified: 04-20-2022, 04:11 AM by GuateGojira )
(04-19-2022, 07:25 AM)Twico5 Wrote: I am not basing all of my statements off of two weights obviously because if I was then I would’ve started this convo by posting them. Do you have proof that belizean Jaguars are dwarfs? Maybe in a paper or something?
Captive weights are relevant because if a puma and a jaguar are both eating the same but are the same size then this would mean that neither is larger simply because they have “different body plans” as you said. Jaguars are not on another tier, they are simply really heavy when they have a lot of things to hunt.
6kg mean prey weight for forested regions vs 110kg mean prey weight for the pantanal region. That is a huge difference. But even the armadillo-eating jags look bulky and healthy. They don’t die of starvation or look malnourished.
*This image is copyright of its original author
*This image is copyright of its original author
In this study from pench NP the average weight of animals consumed by tigers was 82kg. Pench tigers don’t look unhealthy to me and even though this is a really low average prey weight for a tiger population pench tigers are still able to be bulky and large. Except there is a jaguar population that has a higher mean prey weight than these tigers. Stomach contents from Venezuela showed an average weight of 50kg for all prey including domestic and 32kg for wild prey exclusively.
*This image is copyright of its original author
*This image is copyright of its original author
*This image is copyright of its original author
*This image is copyright of its original author
It is the prey base of the population that influences their size. Yes, I totally agree with you. 113kg and 34kg are a big difference in mean prey weight. Given how Jaguars (dwarf Jaguars ofc!) can still be healthy and bulky with an average prey weight of 5kg, pantanal Jaguars as well as Venezuelan Jaguars owe their abnormal size to their prey base.
Let me ask you, why are Jaguars and pumas in nw mexico the same size? I believe you or Pckts said earlier that Jaguars are badly adapted to desert environments, which is true. Body mass however would only be affected by food consumption and not simply by the environment. Let’s see what Jaguars are pumas are eating in Sonora, Mexico!
*This image is copyright of its original author
*This image is copyright of its original author
*This image is copyright of its original author
*This image is copyright of its original author
Woah! So Jaguars are eating better than pumas in mexico. They are scavenging on kills (likely kills of both other jags and pumas), killing calves, white-tailed deer, and peccary. Pumas are scavenging less, killing calves less and that too the calves they kill are smaller.
Jaguars are not on another tier, period. I have posted countless studies these past few days here comparing the diets, prey bases and body masses of pumas and jags but none of that seems to have made a difference and you claim that Jaguars are on another tier still. This idea is one that is pushed by your bias towards Jaguars, and not by factual evidence of any sort.
You have no idea how the studies of prey base work, don't you? The example of the tiger that you put here shows your error.
Using captive specimes is silly, as @Pckts also pointed out. They have different body plans and different metabolism, not even between the Panthera cats they are the same, imagin between a Panthera and an overgrow Felis. It seems that you don't understand hoy important is this point too. For example, a jaguar may be fee with 8 kg per day, and a puma with the same, but if they have different metabolist the jaguar may need more food than a puma of similar size, as they had more mass to sustain, or maybe is the contrary, the puma is more agile and the 8 kg that it eat is metaboliziced faster than the similar sized jaguar. As you can see, they are not the same, so can't compare captive animals even when they are feed the same.
About the tigers, let me educate you how those figures work. First, the figure of 82 kg is not "low" as you may think, in fact even 6 kg for jaguars are not "low" as you want to show. You ignore how the scientists got these numers, don't you? You must learn that the scientists are not weighing every single animal preyed by the cats, that is imposible, they normally get the species preyed via scats (some times via kills) and then they calculate the percentage of consuption in relation with the other prey items (how ofter then kill animal "x" in relation with animal "y" and "z"). After that, the average weight is just estimated using 1/3 of the average weight of the females, for example if the female of a "x" species of deer weight 100 kg, then they will use 75 kg for the calculation with will represent the average weight of the species in the wild, including males/females/youngs, so is an average as a hole (in some documents the average for lions is 100 kg and tigers of 113 kg, to give you an idea). Then they use formulas to calculate the weight in relation with the percetage of consumption (based in numbers of prey hunted, not the actual food intake) and then they calculate the average weight. In the case of Pench, the figure of 82 kg shows that the average prey that tigers weight are about that size, showing a bias for prey of that size as is the most available in the area (certainly chital deer with had an average between 50 - 80 kg adult females and males). However these type of studies can only inform about the prey available, the selectivity of the predator and how often they hunt it in relation with population and density, but do not show how often they kill in relation with food consumption. In this case, the Pench tigers may hunt a prey of 82 kg every week to sustain they need (5 - 7 kg per day) so they cover the basics, but certainly that doesn't say how often they kill it and do not say if they kill bigger prey too. So, for a population of tigers with an average of 113 kg overall (males, females, subadults and cubs included), a random prey of 82 kg is more than enoght to sustain it, based in numbers, but certainly males hunt bigger prey than females, they have different huting rates and consumption, and sttudies like that of Dr Chundawat in Pann TR shows those variations. So no, you example of tigers is futile to explain your point of view.
So, a jaguar with an average prey of 6 kg probaby will fill they needs killing one animal per day but latter killing a large pecari eery week to sustain. Scats analisys tend to overestimate small prey based in the hair present in the feces, that is why is good to compensate with killls. Also only kills overestimate large animals over the smalls. In that scenario jaguars in Belize are ok with that prey base, but you don't know how often they hunt it, there is where you fail, because you don't take in count the full spectrum of the situation, you just mention the numbers, but you don't have the backup to prove that pumas an jaguars had the same food consuption, or the same kiling rate, or the same food intake.
Saying that Pantanal and Venezuela jaguars are "abnormal" is completelly false, as @Pckts and @"LoveAnimals" showed to you, the main prey base are wild animals. But prey base and food consumption is not all, as a Belize jaguar will not grow to the same size as Pantanal until several generations enjoyed the prey base, and the same with the Pantanal jaguars became like Belize in size. However, again, you see that the biggest pumas in Alberta, Washington or Chile, even with a good prey base and large prey items, they do not weight as the largest jaguars.
About the Sonora jaguars and pumas, I don't see your point. If jaguars are killing cattle is obviously because they wild prey is low, that is a penomenon with any large cat (tiger, lions, leopards, etc). Meanwhile the pumas are better adapted for smaller prey and its consuption in cattle is smaller. Also, as I told you before, the bigger cat probably had more needs, so jaguars need to kill bigger prey to live and that is why they prefer cattle when is available, after all Hayward et al. (2016) explain this phenomenon as the jaguar evolved to kill bigger prey, not the prey that is living in America in these time. Pumas, on the other hand, evolved to kill small prey and is until now that bigger cats got extinct that they started to kill bigger prey. Two oposite situations, two completelly different body plans and two different metabolisms.
The "countless" studies that you posted do not show that you pretend, for the contrary, only with the correct interpretation is that we manage to understand the full aspect and you can't use only the plan values if you don't have the other details that I mentioned you before. Is like the case of your comparative images, without real proof of the sex, age, health status and location, you can't actually compare the two species.
I think that I am done with this, there is no point in this discussion. I will focus in the Smilodon issue, if it continue of course.
(04-20-2022, 02:39 AM)Twico5 Wrote: I never mentioned caatinga jags a single time in that post. Guate called Costa Rican and Mexican Jaguars “dwarf jaguars” despite the fact that they are feeding on chelonians which are pretty much free kills for obvious reasons and calves in nw Mexico.
I demand you to show where I said that Costa Rica and Mexican jaguars are dwarf. Show it, right now.
(04-20-2022, 02:39 AM)Twico5 Wrote: I never mentioned caatinga jags a single time in that post. Guate called Costa Rican and Mexican Jaguars “dwarf jaguars” despite the fact that they are feeding on chelonians which are pretty much free kills for obvious reasons and calves in nw Mexico.
I demand you to show where I said that Costa Rica and Mexican jaguars are dwarf. Show it, right now.
(04-19-2022, 07:25 AM)Twico5 Wrote: I am not basing all of my statements off of two weights obviously because if I was then I would’ve started this convo by posting them. Do you have proof that belizean Jaguars are dwarfs? Maybe in a paper or something?
Captive weights are relevant because if a puma and a jaguar are both eating the same but are the same size then this would mean that neither is larger simply because they have “different body plans” as you said. Jaguars are not on another tier, they are simply really heavy when they have a lot of things to hunt.
6kg mean prey weight for forested regions vs 110kg mean prey weight for the pantanal region. That is a huge difference. But even the armadillo-eating jags look bulky and healthy. They don’t die of starvation or look malnourished.
*This image is copyright of its original author
*This image is copyright of its original author
In this study from pench NP the average weight of animals consumed by tigers was 82kg. Pench tigers don’t look unhealthy to me and even though this is a really low average prey weight for a tiger population pench tigers are still able to be bulky and large. Except there is a jaguar population that has a higher mean prey weight than these tigers. Stomach contents from Venezuela showed an average weight of 50kg for all prey including domestic and 32kg for wild prey exclusively.
*This image is copyright of its original author
*This image is copyright of its original author
*This image is copyright of its original author
*This image is copyright of its original author
It is the prey base of the population that influences their size. Yes, I totally agree with you. 113kg and 34kg are a big difference in mean prey weight. Given how Jaguars (dwarf Jaguars ofc!) can still be healthy and bulky with an average prey weight of 5kg, pantanal Jaguars as well as Venezuelan Jaguars owe their abnormal size to their prey base.
Let me ask you, why are Jaguars and pumas in nw mexico the same size? I believe you or Pckts said earlier that Jaguars are badly adapted to desert environments, which is true. Body mass however would only be affected by food consumption and not simply by the environment. Let’s see what Jaguars are pumas are eating in Sonora, Mexico!
*This image is copyright of its original author
*This image is copyright of its original author
*This image is copyright of its original author
*This image is copyright of its original author
Woah! So Jaguars are eating better than pumas in mexico. They are scavenging on kills (likely kills of both other jags and pumas), killing calves, white-tailed deer, and peccary. Pumas are scavenging less, killing calves less and that too the calves they kill are smaller.
Jaguars are not on another tier, period. I have posted countless studies these past few days here comparing the diets, prey bases and body masses of pumas and jags but none of that seems to have made a difference and you claim that Jaguars are on another tier still. This idea is one that is pushed by your bias towards Jaguars, and not by factual evidence of any sort.
You have no idea how the studies of prey base work, don't you? The example of the tiger that you put here shows your error.
Using captive specimes is silly, as @Pckts also pointed out. They have different body plans and different metabolism, not even between the Panthera cats they are the same, imagin between a Panthera and an overgrow Felis. It seems that you don't understand hoy important is this point too. For example, a jaguar may be fee with 8 kg per day, and a puma with the same, but if they have different metabolist the jaguar may need more food than a puma of similar size, as they had more mass to sustain, or maybe is the contrary, the puma is more agile and the 8 kg that it eat is metaboliziced faster than the similar sized jaguar. As you can see, they are not the same, so can't compare captive animals even when they are feed the same.
About the tigers, let me educate you how those figures work. First, the figure of 82 kg is not "low" as you may think, in fact even 6 kg for jaguars are not "low" as you want to show. You ignore how the scientists got these numers, don't you? You must learn that the scientists are not weighing every single animal preyed by the cats, that is imposible, they normally get the species preyed via scats (some times via kills) and then they calculate the percentage of consuption in relation with the other prey items (how ofter then kill animal "x" in relation with animal "y" and "z"). After that, the average weight is just estimated using 1/3 of the average weight of the females, for example if the female of a "x" species of deer weight 100 kg, then they will use 75 kg for the calculation with will represent the average weight of the species in the wild, including males/females/youngs, so is an average as a hole (in some documents the average for lions is 100 kg and tigers of 113 kg, to give you an idea). Then they use formulas to calculate the weight in relation with the percetage of consumption (based in numbers of prey hunted, not the actual food intake) and then they calculate the average weight. In the case of Pench, the figure of 82 kg shows that the average prey that tigers weight are about that size, showing a bias for prey of that size as is the most available in the area (certainly chital deer with had an average between 50 - 80 kg adult females and males). However these type of studies can only inform about the prey available, the selectivity of the predator and how often they hunt it in relation with population and density, but do not show how often they kill in relation with food consumption. In this case, the Pench tigers may hunt a prey of 82 kg every week to sustain they need (5 - 7 kg per day) so they cover the basics, but certainly that doesn't say how often they kill it and do not say if they kill bigger prey too. So, for a population of tigers with an average of 113 kg overall (males, females, subadults and cubs included), a random prey of 82 kg is more than enoght to sustain it, based in numbers, but certainly males hunt bigger prey than females, they have different huting rates and consumption, and sttudies like that of Dr Chundawat in Pann TR shows those variations. So no, you example of tigers is futile to explain your point of view.
So, a jaguar with an average prey of 6 kg probaby will fill they needs killing one animal per day but latter killing a large pecari eery week to sustain. Scats analisys tend to overestimate small prey based in the hair present in the feces, that is why is good to compensate with killls. Also only kills overestimate large animals over the smalls. In that scenario jaguars in Belize are ok with that prey base, but you don't know how often they hunt it, there is where you fail, because you don't take in count the full spectrum of the situation, you just mention the numbers, but you don't have the backup to prove that pumas an jaguars had the same food consuption, or the same kiling rate, or the same food intake.
Saying that Pantanal and Venezuela jaguars are "abnormal" is completelly false, as @Pckts and @"LoveAnimals" showed to you, the main prey base are wild animals. But prey base and food consumption is not all, as a Belize jaguar will not grow to the same size as Pantanal until several generations enjoyed the prey base, and the same with the Pantanal jaguars became like Belize in size. However, again, you see that the biggest pumas in Alberta, Washington or Chile, even with a good prey base and large prey items, they do not weight as the largest jaguars.
About the Sonora jaguars and pumas, I don't see your point. If jaguars are killing cattle is obviously because they wild prey is low, that is a penomenon with any large cat (tiger, lions, leopards, etc). Meanwhile the pumas are better adapted for smaller prey and its consuption in cattle is smaller. Also, as I told you before, the bigger cat probably had more needs, so jaguars need to kill bigger prey to live and that is why they prefer cattle when is available, after all Hayward et al. (2016) explain this phenomenon as the jaguar evolved to kill bigger prey, not the prey that is living in America in these time. Pumas, on the other hand, evolved to kill small prey and is until now that bigger cats got extinct that they started to kill bigger prey. Two oposite situations, two completelly different body plans and two different metabolisms.
The "countless" studies that you posted do not show that you pretend, for the contrary, only with the correct interpretation is that we manage to understand the full aspect and you can't use only the plan values if you don't have the other details that I mentioned you before. Is like the case of your comparative images, without real proof of the sex, age, health status and location, you can't actually compare the two species.
I think that I am done with this, there is no point in this discussion. I will focus in the Smilodon issue, if it continue of course.
Of course we dont know actual consumption rates but we do know that jaguars killed 45 cattle while pumas only killed 12. Jaguars killed calves weighing up to 200kg they definitely were consuming more. Jaguars were also killing whitetailed deer maybe even taking larger ones and adults more often than pumas since you said theyre better adapated at killing larger prey.
Pumas are generalists, jaguars are specialists. There is no other explanation for the differences or similarities in size between these two cats across their range. Pumas kill whatever is in abundance, and jaguars will kill anything but thrive especially when prey they are good at hunting is in abundance. I dont think cattle fall under what jaguars have evolved to hunt, so i have to disagree with you on that. I think cattle are just one of the many prey items jaguars will take because they are capable of killing and eating just about anything.
And yeah maybe it isnt abnormal for a specialist carnivore to get really big in certain areas but if this were to be the case with leopards or pumas for example it would be abnormal because their diets look different
Still though i would like to point out 3 things ive said so far that i stand by and are true
1. Only floodplain jaguars outsize the largest puma populations
2. At least in an area where both cats tend to be the same size there would definitely be mutual avoidance
3. Puma size isnt affected at all by the presence of jaguars, their populations arent supressed by jaguars and they never have to resort to hunting different prey because of jaguar presence
04-20-2022, 02:40 PM( This post was last modified: 04-20-2022, 02:45 PM by LonePredator )
@Twico5 You are claiming that just because pumas sometimes have similar length and height as jaguars then pumas would also have the same mass if they eat same prey?
This logic is completely flawed. Would you say that a Cheetah would attain the same weight as a Leopard also just because their height and length overlap?
Lions and Tigers are also close in length and height but Tigers inherently have a different kind of body structure which is why Tigers are a bit heavier. This is even the case when Lions have slower metabolism.
EVEN with a FASTER metabolism, Tigers are still heavier just because of their inherently different body structure.
Similarly, the body structure between Jaguars and Pumas is so vastly different that Jaguars can pack much more mass.
This is the reason Jaguars are said to be so robust. Jaguars simply have such a body structure which allows them to pack more mass even with the same length and height as Cougars.
