North American bobcats and lynx, wildlife identification


This 2010 video from Texas in the USA says about itself:

Shot over a 2 year period, this video chronicles the 6 episodes of 2 different bobcats that visited our yard on a creek in far North Dallas; one probably raised in captivity and the other very wild indeed.

From the University of British Columbia Okanagan campus in Canada:

Copy cats: When is a bobcat not a bobcat?

Telling similar animals apart challenges even the experts

January 23, 2019

Two UBC Okanagan biologists, who have publicly solicited images of wild cats for their research, have answered that question.

Their recently published study explains how hard it can be when it comes to wildlife classification — even experts have difficulty agreeing on whether a cat in a picture is a bobcat or a lynx.

Biology Professor Karen Hodges and master’s student TJ Gooliaff collected and compared wildlife images for several years as part of their research tracking bobcat and lynx distributions in British Columbia. Camera trapping and solicitation of wildlife pictures through citizen science have become common tools in ecological research, explains Gooliaff.

While it’s generally easy to collect many images of animals, some species are difficult to tell apart, making species classification challenging.

Camera-trapping and citizen-science studies collect many wildlife images for which correct species classification is crucial,” says Gooliaff. “Even low misclassification rates can result in erroneous estimation of the geographic range or habitat use of a species — including underestimation of the occupancy, habitat preferences or distribution of a species. This potentially hinders conservation and management efforts.”

There are some species, such as mountain goats and porcupines, where it’s obvious. But for others, including bears, deer, lemurs, wild cats and antelopes, classification to a species may be unreliable as the animals can be similar in size, shape or colour. It gets even trickier when the pictures are blurry, taken in poor lighting, show only part of the animal or when only one image is available for a given animal.

In a 2018 study published in the Journal of Wildlife Management, Gooliaff and Hodges solicited 4,399 images of bobcats and lynx from the public across British Columbia to examine the provincial distribution of each species. They used pictures, trapping records and other data sources to develop current range maps.

Because lynx and bobcats are similar, Gooliaff and Hodges then measured agreement among experts who were asked to distinguish between bobcats and lynx from those images. The researchers asked 27 individual bobcat and lynx authorities to classify the species in a subsample of 300 images to see how often the experts agreed on whether it was a bobcat or a lynx.

What became clear was that the experts found it difficult to tell bobcats and lynx apart — indeed, many images were labelled as “unknown” by the experts — and they did not always agree with each other. Experts were inconsistent even with themselves, changing their classifications of some images when they were asked to reclassify the same pictures months later.

Gooliaff and Hodges also examined if agreement among experts varied with what part of the animal was in each image (paws, head, tail, etc.), the habitat in the background, and whether it was day or night. These factors all affected how many experts agreed on the species in each image.

“These results are particularly troubling given that the images were all of high photographic quality,” says Gooliaff.

Hodges says this study helps researchers improve how they work with images, by knowing when misidentifications are most likely. Further, classification of images of similar?looking species should not be relied upon for critical conservation or management decisions. Instead, physical or genetic evidence should be required in these cases.

She also emphasises that pictures provided by the public are becoming a powerful tool in wildlife research and eventual conservation and management efforts. This research benefits citizen science and image-based studies, as they continue to refine how people use submitted images.

“We encourage researchers who use images to be more willing to call the species in a picture “unknown” or to use them as a screen for habitats or regions where more survey work should be done, rather than trusting images alone.”

The image study, partially funded by a Natural Sciences and Engineering Research Council grant, was recently published in Ecology and Evolution.

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Prehistoric big cats, video


This 7 December 2018 video says about itself:

10 Amazing Big Cats From Prehistory Some Of Which You May Not Have Heard Of

Before human beings, Felidae, or cats, were the most successful, powerful predators in most of the world. Even today, big cats such as tigers, lions, jaguars and leopards keep causing admiration and fear, but these magnificent beasts are dwarfed by some of their extinct relatives.

Here are prehistory’s largest, mightiest cats, some of which were seen by humans only a few thousand years ago.

1- Giant Cheetah The Giant Cheetah (Acinonyx pardinensis), belonged to the same genus as modern day Cheetah (Acinonyx jubatus), and probably looked very similar, but it was much bigger.

2- Xenosmilus hodsonae Xenosmilus hodsonae is a relative to Smilodon (“saber-toothed tiger”), but instead of having long, blade-like fangs, it had shorter and thicker teeth.

3- Giant Jaguar In prehistoric times, both North and South America were home to gigantic jaguars, belonging to the same species as modern day jaguars (Panthera onca) but much bigger.

4- European Jaguar It was a huge predator, weighing up to 210 Kgs (463) or more, and probably at the top of the food chain in Europe, 1.5 million years ago. Its fossil remains have been found in Germany, France, England, Spain and the Netherlands.

5- Cave Lion The Cave lion was a gigantic subspecies of lion, weighing up to 300 kgs (661lbs) or more (and therefore, being as large as the Amur or Siberian tiger, the largest cat of our days.

6- Homotherium serum Also known as the “Scimitar cat”, Homotherium serum was one of the most successful felines in prehistoric times, being found in North and South America, Europe, Asia and Africa.

7- Machairodus aphanistus Machairodus aphanistus probably looked pretty much like a gigantic tiger with saber teeth; it had very tiger-like proportions and a long tail, although it is impossible to know if it had stripes, spots or any other kind of fur markings.

8- American Lion The American lion or Panthera atrox, is probably the best known of all prehistoric cats after Smilodon. It lived in both North and South America (from Alaska to Peru) during the Pleistocene epoch, and went extinct 11,000 years ago, at the end of the last Ice Age.

9- Pleistocene Tiger The most obscure cat in the list, being known from fragmentary remains which have yet to be formally described. Most likely “Pleistocene tiger” is not a separate species, but rather the “early version” of the same tigers we see today. It is also known as Ngandong tiger.

10- Smilodon Smilodon is one of the most famous prehistoric predators, and also one of the most formidable. There were at least three species living in both North and South America; the smallest species, Smilodon gracilis, was about the size of a modern day jaguar, while Smilodon fatalis was as big as a lion.

Puma cubs outside den for first time


This video, recorded in Chile, says about itself:

Adorable Puma Cubs Explore the Wild for the First Time

23 November 2018

A puma lets her three kittens run through the scrub in the Torres Del Paine region of Patagonia. It’s their first excursion out of the den – they’re too young to hunt, but they’re ready to explore their new world.

What injured saber-toothed cats ate


This April 2017 video is called Prehistoric Predators – Sabertooth.

From the Geological Society of America:

Saber-toothed cats with oral injuries ate softer foods

November 5, 2018

Saber-toothed cats with oral injuries ate softer foods than their uninjured counterparts, who may have provided injured cats with soft scraps.

Indianapolis, IN, USA: Saber-toothed cats, the large felid predators that once roamed Southern California, may have eaten softer foods after suffering oral injuries, according to a new study. Microscopic damage patterns on teeth from fossilized cats show the injured predators transitioned to seeking softer prey, like flesh instead of bone, which healthy cats may have provided for them, according to the study.

Saber-toothed cats likely suffered injuries while felling large prey, according to the study’s lead author, vertebrate paleontologist Larisa DeSantis from Vanderbilt University, Tennessee.

The cat’s prey animals were larger 10,000 to 50,000 years ago, DeSantis says, and could have easily broken jaws or kicked teeth completely free from the socket, leading to subsequent and sometimes lethal infection. It’s unlikely that cats with such severe injuries could take down large animals and consume their soft, fleshy meat, she says, or even survive long after the injury.

“The fact that they’re eating food that really shouldn’t be available to them unless they’re being provided for, and that they’re living with these injuries for prolonged periods of time suggests they’re being provisioned food by other cats”, she says. DeSantis will share her findings on Monday, 5 November, at the Geological Society of America Annual Meeting in Indianapolis, Indiana.

Microdamage patterns recorded in tooth enamel, like mountains and valleys in a topographic map, tell the history of an animal’s diet. These patterns allow researchers to glean information like whether a predator was scavenging on bone or eating tougher foods like flesh. Anthropologists have pioneered the same technique to explore the diets of early human ancestors.

DeSantis and her colleagues compared the dental microwear patterns of injured versus uninjured cats, thanks to a large pathology collection available at the La Brea Tar Pits and Museum in Los Angeles, California. Many of the fossils show signs of prolonged infection and bone growth associated with healing — signs that the animals survived after what would have been fatal injuries if not part of a social group.

“What’s really exciting about this,” DeSantis says, “is that you see pretty clear evidence that they’re surviving for longer. That in itself gives you evidence of potential care within the social group.”

These findings further support the idea that saber-toothed cats were social animals, being an exception to the rule of non-sociality in the lion’s share of felid species. Saber-toothed cats consumed both flesh from fresh kills and utilized carcasses.

“There is a lot of evidence that Smilodon was a social and gregarious animal”, says Christopher Shaw, Collections Manager Emeritus at the La Brea Tar Pits and Museum and coauthor on the study, “which implies that they hunted together and fed at group kills. This study adds another provocative aspect to the sociability within this species and, for the first time, addresses new evidence regarding food options and feeding behaviors for injured members of the social group.”

DeSantis’s interest in this work began in an earlier study, where she found that man-eating lions may have turned to human prey, in part, because of similar oral injuries. Preserved teeth of confirmed, man-eating lions stored at the Field Museum of Natural History in Chicago, Illinois, showed patterns of wear that were similar to captive zoo lions, which ate soft foods consisting mostly of beef and horse meat.