It seems my recent webinar on bears of the world and their biology was a big hit. With a topic as huge as the 8 species of bears in the world, and their complex biological topics such as hibernation, reproduction and evolution, there were obviously many questions, as I only have an hour for a webinar. Here is the list of questions we received from the audience, and my answers. Each question could deserve much more information, but I tried to keep things fairly simple. Feel free to ask follow up questions in the comment section! Firstly, here is a recorded version of the webinar. and second is a narrated version of the mating season fighting and behavior video I showed in the webinar.
If a female does not mate unless they don’t have a cub around, how do they end up with 1 and 2 and 3 year cubs that still hang around mom? When a mother bear decides when to break from her cubs, of which depends on the species (1.5 years for black bears, 3-4 years for brown/grizzly bears), she must violently break the bond, as the cubs do not want to leave mom. The mothers will quit nursing, and come into estrus during the next mating season. The mother will not care for the older cubs any longer in theory, although they may still follow mom from a distance. There have been a few observations, although extremely rare, of mothers with mixed ages hanging together, but I have never seen this myself.
What is the lifespan of a bear? All bears generally live to around 30. Female bears live about 5 or more years longer on average than males, likely due to body damage due to mating season fights. Polar bears seem to live less than brown/grizzlies. Bears in better habitats live longer, as there was a huge male bear named “Diver” at Brooks Falls who lived to 35, and there was a female at McNeil River that lived to 36. A wild Minnesota black bear recently died at almost 40 years old! Polar bears in captivity have lived into their late 30’s, and other captive bears have lived into their 40’s.
Are poler bears adapting to climate change and if so, how? Polar bears are extremely vulnerable to global warming as sea ice, which they rely on for a seal-hunting platform disappears. They are not adapted for terrestrial life, as their body burns so many calories to thermoregulate and travel, if they don’t get huge calorie seal meals, they cannot make ends meet. Hungry bears are becoming more bold and causing problems in human communities looking for food. The first sign of their stressed condition is a drop in the number of cubs that females can successfully produce. I will talk more about this in this week’s webinars, on polar bears on Wednesday May 20. Register here!
Are there still a lot of bile farms still running in China and Vietnam? It is estimated that 10,000 farmed bears exist in Chinese bear farms, and 1000 in Vietnam. There are approximately 100 large scale farms in Asia. The Governments have banned creation of new farms, and closed many farms. There were over 400 farms in the 1990’s, so there has been a decrease. Bear farming has been illegal since 2005 in Vietnam, but farmers can still keep existing bears as “pets” and extract bile. Bear bile trade is a 2 billion dollar/year industry, so curbing consumer demand is really the key. Read more here about bear farming from Animals Asia.
Why has synthetic bear bile not replaced natural bear bile? Is synthetic bear bile more expensive? This is a tough question, because the price for real bear bile is all over the map, with the highest value existing in Japan where it is worth 4 times its in weight gold, to much lower value in Thailand for example. My guess is synthetic bile, know in the USA as “Actigal” is more expensive than bear-farm bile. Wild bear bile would be considered purest and most valuable.
What animals, other than bears, have delayed implantation? Delayed implantation, also known as embryonic diapause, is present in 100 different mammal species, including marine mammals, members of the weasel family (badgers, martens and weasels), marsupials and armadillos.
Can a snaggle-tooth bear still feed normally? Feeding for a snuggle tooth condition, which is a tooth that is broken and heals back in the wrong position, looks to be more difficult, and would hinder the ability for a polar bear to kill a seal as easily, or a brown bear to be able to chew sedges as efficiently, but I have seen many healthy old males who lived with this condition for many years.
Do most / any bears have multiple cubs? Yes, all bears have an average of two cubs. Pandas also have two cubs, but the mother can only support one cub, so she abandons one. In captivity, the abandoned cub is retrieved by panda keepers after birth and raised in an incubator, and the skilled keepers will switch the cubs with mom every 2 weeks, so they both get experience with mom. I have seen a brown bear with 4 cubs twice in my life, but there 4th cub never survives for very long, was the mother has only 6 teats and one of the cubs becomes a “runt” and eventually cannot keep up with the family.
Does the new ban on the wildlife trade in China due to the supposed source of Covid 19 include bears? China Yes, wild bears are included in this ban, but wild bear poaching is already illegal. This ban does not include farmed bears, in fact, sadly, the Chinese Government recommends bear bile (not from wild bears) as a treatment for corona. The illegal blackmarket trade and that demand, is unaffected by any change in laws- strict enforcement, NGOs like WildAid, and the decrease in demand due to an increase in public awareness and appreciation of nature are the keys to success. Here is a recording of last week’s webinar I did on China’s change in their perception of nature.
Do the bears use their claws when they fight, or just their teeth? They certainly use their claws and paws to grip their opponent, and swat and slap their opponents. I have often seen serious injuries inflicted by claws in fights.
What types of diseases do bears get? I have hardly ever hear about diseases in wild bear populations. There was a problem with captive pandas contracting canine distemper in a panda breeding center in Shaanxi province years ago, but the details were very difficult to come by in China. I have recently read an article about mange, spread from canines, affecting Eastern US black bears, but this is rare because bears are not social animals so it is difficult for the disease to spread. If bears are healthy, they can deal with most diseases, but if they are nutritionally stressed, their immune system can be compromised. In 2015 a bear cub died at Brooks Falls and after a necropsy the Park Service determined it likely died of a virus carried by dogs called CAV-1 (infectious canine hepatitis) and many bears on the Alaska Peninsula carry antibodies for it. Read the full story here. Bears, like all warm blooded animals can contract and suffer from rabies, but there have only been several cases ever recorded in the world. Here is an article for more info on bears and rabies.
At one time Spain had a large population of bears. This nation’s insignia is a bear. However due to humans, the population has greatly diminished. Comment? I agree, the Spanish brown bear is nearly extinct, and only a few are left in the Pyrenees Mountains of the north. California also has the brown bear (grizzly) on their state flag, but that population is extinct. The grizzlies of Mexico, Scotland and England, and the great plains of the USA are other of the many examples of extinct bear populations.
Do female bears mate solely with one male bear. Do male bears mate with more than one female? Yes male and female bears mate with many partners if available during the mating season. I once saw a female mate with 9 different males in one day when I was a ranger at McNeil River State Game Sanctuary in Alaska. A female can have two or three cubs, all of different fathers. This is a good way to have diversity in their litter in case one father’s qualities are not suited for a particular situation, such as longer fur during a warm period.
How do you tell if the big bears are playing or fighting? The speed and intensity of the fights are vastly different for true fighting bears versus play fighting or sparring. Here are two examples- first is sparring, second video is fighting.
Are there more male cubs born than female cubs? There is an equal 50/50 ratio of males and females.
Do bears mate with their offspring? Possibly, yes, but I have never seen this happen, and I recognize many bears that come from particular females. I really do not know. Just about anything can happen in the world of bears, so I am sure it happens sometimes.
Are the males usually bigger than females? Yes, males of brown bears and polar bears can be double the size, while the difference between sizes in pandas is much less. The difference in male/female features is called sexual dimorphism.
Do they ever die from wound infection after a fight? According to my observations, bears are extremely resistant to inflections even when the wounds are very severe. Their immune systems seem specially evolved for this.
Bears ears are very small. Do they not rely much on hearing? They have similar hearing to dogs. Bears are not specialized to hunt small prey like foxes that hunt voles in tall grass, so they rely on hearing to a lesser extent than many predators. Rabbits, have huge ears to detect stealthy predators, and bears are not worried about this.
Do the first or second year cubs hibernate with their mother? Yes, bear cubs hibernate with mom until they separate which is between 1.5-4 years depending on the individual and the species.
Have you ever seen Otis at Brooks Falls? Do you know how old he is? I have spent every summer since 2000 guiding on the coast of Katmai National Park, which is very far from Brooks, so I have actually have never been there! But I do know that Otis is the oldest bear at Brooks falls at 22. Early- mid 20’s is old for a male brown bear.
What is going on with the Pebble Mine? We are still waiting to hear the Army Corps of Engineers ruling of Northern Dynasty Minerals proposal. We will know in the summer. If the decisions favors the mine, it will be law suits against the EPA by anti-pebble organizations. Now we can contact our senators and let them know how strongly you feel against the idea. Check out Friends of McNeil River for more info. Your donations will help pay legal fees for the lawsuit. Here is recorded version of our Pebble Mine Webinar-
Why cant the synthesized bile be promoted more to prevent the poaching? Hopefully it can as public awareness overrules the ancient traditions of Traditional Asian Medicine. Check out Animals Asia for more info.
Are the male bears more touchy during breeding season? Yes, they have super boosted levels of testosterone, and are obsessed with locating and competing for females. They are not more dangerous to our groups when bear viewing, however, because we are not part of the equation- we are just neutral observers and stay out of their way and their affairs, and watch from a safe distance.
Do bears hibernate alone? Yes, bears hibernate alone, except for the mothers with cubs. They hibernate together until the mother kicks out her litter.
What is the scientific/formal name for bear bile and is there more than one synthetic form? My nephew suffers from kidney stones and maybe could use the synth form,. Would never suggest the real thing. This would be something to ask your doctor. Also, I misspoke, bear bile is very effective for gall stones, also possibly kidney stones, but I am not totally sure. This is a serious medicine so it should be used with caution. The name is “Actigal” and is commonly used for large domestic mammals by Veterinarians.
Thanks guys for the interest and all of the great feedback! Your support is keeping this program going for us guides to keep doing what we love! Without having a webinar to do once a week I may gone crazy by now!
Love you guys, tune in Wednesday for “A year in the life of a Hudson Bay Polar Bear!
Brad
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