Felids
 
                                      
          American puma (Felis concolor)                                     South American jaguar (Panthera onca)
 
 
Asian tiger (Panthera tigris)                                                                                                                                                                                                                                                                      
                                                          
Lion (Panthera leo)
 
                                             
                 African Leopard (Panthera pardus)                                Snow Leopard (Panthera uncia)
 
 
                                         
                                                    Clouded Leopard (Neofelis nebulosa).  
 
                                                             
                Cheetah (Acinonyx juba)                    Lynx (Lynx lynx)               Bobcat  (Lynx rufus)
 
 
 
Pre-Holocene Predators on Bears
 
 
 
Other Enemies
 
NOTE: Many of the skulls and skeletons shown here are replicas,
available for purchase from Bone Clones www.boneclones.com
Herrero (1972) noted that most bear species defend themselves primarily by escaping -- e.g., into trees -- from non-arboreal enemies, but that grizzly bears often lack that option when they occupy habitat without climbable trees.  He speculated that this put a premium on defense through strong offense, accounting for the grizzly’s legendary violent defensiveness.   Note that Ursus arctos on the Pacific sea coast, where trees are more common, are much less quick-tempered, at least toward people, than are grizzlies from inland habitats where climbable trees may be scarce.  If Herrero’s logic is valid, Arctodus and other prehistoric bears unable to find refuge in trees -- due to the bear’s own morphology or to scarcity of adequate trees -- may well have been under even greater selection pressure that U. arctos for violent defensiveness.
    The dependence of North American black bears on trees for refuge would suggest that they would have a harder time than some other ursids migrating across arid plains and other habitats with scarce trees.  This might explain why they apparently never migrated south of Mexico, much less into South America, whereas the much larger prehistoric Tremarctos did.
 
 
 
PREDATORS
    Predation on bears is now uncommon.  But that may not have always been true, especially where cubs are concerned.  The greatest vulnerability of bears is and probably always has been to social canids, as well as hyenas (in groups and perhaps singly) and large felids.  During the Holocene, bears have had to cope with the following species:  
 
Holocene  
Hyaenidae:  Asian hyena (Hyaena hyaena) and perhaps other species.
 
 
Spotted hyaena (Crocuta)
 
 
Canidae of the Northern Hemisphere:  Wolves in North America and Eurasia, as well as possibly wild "dogs" in Asia (Cuon alpinus) and South America (Dusicyon, Cerdocyon, Spethos venaticus):
 
                             
Siberian wolves (Canis lupus)
 
 
Chapter 15
DEFENSE AGAINST ENEMIES