I just saw remarkable documentary on National Geographic Wild about a particular wolf living in Yellowstone. It was called The Rise of Black Wolf.
Some of the best nature documentaries are biopics about a particular wild animal, and this particular wolf was quite an interesting character. He lived for about ten years in Yellowstone National Park, which is actually quite long for a wild wolf.
He also sired a lot of puppies.
But how he was able to achieve both was truly remarkable.
Most of us know about wolf packs that are based upon a breeding pair. They are two, usually unrelated, wolves that form a pair bond. They are fairly monogamous. The male in the pair does he can to keep his sons and interlopers from breeding with his mate, and the female also does everything to keep other females away from her mate, including social suppression of estrus. Yellowstone packs are unique in that they often have multiple breeding females.
However, these females don’t tend to breed with wolves in their own pack. Very often, they are the daughters of the breeding pair, and because wolves have very strong inbreeding avoidance behavior, they would not mate with their father. And they certainly weren’t going to mate with their brothers, who very often leave the pack by the time they are two or three years old.
To breed, they often consort with lone male wolves that come near the pack territories during the mating season. These wolves are often called “Casanova wolves.” They are young males that have left their natal packs in search of new territories and mates, but very often, neither can be procured. So while thy are without mates or territories, they often take to mating with the daughters of an established breeding pair. In normal wolf packs, bitches other than the breeding female typically don’t raise their pups to maturity. They often don’t have access to dens or food for their offspring.
Yellowstone is different. Because the wolves live in an area with relatively abundant prey, packs often have enough resources to allow these females to raise their litters.
Because it is not normal for more than one female wolf in a pack to raise a litter to maturity, such breeding are not a sure strategy.
The wolf in this particular documentary did something unusual: He based his entire reproductive strategy upon being a Casanova.
He found that he could hang out at the margins of the territory of the Druid pack and mate with the female daughters of the breeding pair. He pair-bonded with none of them. He was a love ’em and leave ’em kind of guy.
But over time, he wound up siring more puppies that the original breeding male in the pack and his successor, who were both forced to mate with only their mates. During the tenure of the first breeding male, the Casanova had a hard time breeding with his daughters. The breeding would attack the Casanova if he caught him, but the Casanova figured out that the breeding male had a taboo about going near a road that ran through the edge of the pack’s territory. The Casanova used the road as his base from which he would launch his romantic forays. When another breeding male took over after the death of the first breeding male, the Casanova was tolerated, even allowed to become fully part of the pack. He was still breeding with all the females in the pack, except for the breeding male’s mate.
And such a strategy is very successful, but it is entirely reliant upon a wolf pack allowing more than one female to raise her offspring.
And that typically happens only in areas of material abundance.
As you may be thinking, dogs typically employ a Casanova strategy. Dogs can pair bond, but it is not the norm.
Dogs are able to utilize this strategy for the same reason that the Casanova wolf did: Most female dogs living even within the margins of human society are able to raise at least some of their puppies to maturity.
Dogs that are able to utilize this strategy are better able to spread their genes than those that employ are pair bonded within a pack system. From a gene-centered view, the only reason why wild dogs pair bond or form packs based upon the offspring of a bonded pair is so that more resources can be devoted to raising litter. (See kin selection).
In a situation where a pack can raise more than one litter– as is the case in Yellowstone and with domestic dog population– it makes much more sense not to pair bond.
That Casanova wolf in the documentary wound up siring more puppies than any wolf in Yellowstone. That is not a trivial influence upon the population genetics of any population. If animals can produce more offspring without forming an almost entirely exclusive pair bond, then that animal will spread its genes into more descendants.
That reason alone is probably why virtually all domestic dogs have given up the pair bond behavior. A male dog can spread his genes to more descendants if he’s not tied to one bitch.
Of course, when domestic dogs become wild again, as has happened with the dingo, the pair bond returns.
It is really remarkable that Canis lupus has developed these two very different strategies for reproduction. Neither is useful every situation. If a wolf pack allowed all its females to raise a litter in areas where prey was often scarce, the pack would likely never raise any litter to maturity.
Casanova wolves probably tell us how and why dogs gave up the pair bond. It’s just not an efficient way of spreading genetic material in ecological niche in which many females can breed and raise their offspring to maturity.
In those situations, it is more efficient to sleep around.
If dogs had remained within the pair-bond breeding system, we would not have the popular sire effect.
It would also be very hard to selectively breed– but we are still able to do it with other pair-bonding species, just as budgies and Mongolian gerbils.
It’s just easier to selectively breed with animals that don’t pair bond.
Of course, even pair bonded wolves breed with wolves other than their mates!
Reminds me of Ethiopian wolves, where the female sneaks out of the group and fools around.
I wouldn’t use “normal” to describe the more commonly observed mating behavior being limited to the dominant pair only.
The YNP is the most carefully observed wild pack other than the Ellsemere Island ones. Who knows what mating behavior exists in other packs? Why would you think that dispersing/dispersed males wouldn’t also try to mate with a dominant female?
Very rarely do they do get an opportunity to mate with her. The breeding pair, in general, has very strict control over what other wolves do to their mates. Bitch wolves have extreme social suppression of estrus– as in the bitches physical halt estrus sooner if they are not a breeding female.
I’m sure it happens. Lots of hanky-panky in wild dogs.
The ones in Ellsmere pretty much follow the pair-bond breeding system.
Just like people…
Anthropology 101:
In cases where there’s a lot of resources to go around, society tends to be male-orientated. In societies where there’s not enough resources, society tends to be female-orientated; and in cases where there’s only enough resources to survive, monogamous pairs form.
I think a great deal of what we “know” about wolves is based on animals living in what are relatively depleted environments and often in high stress from hunting, etc. It’s hard to say that Casanovas would have been all that rare in a more “normal” environment. As one study of birds found when they actually did DNA tests, what appears to be a pair bond may not be as strict as it appears. I think the Geographic special indicated that the “black wolf” himself was NOT the son of the alpha male, but one of the Alpha’s daughters. There’s a few newer studies (including one on lizards, IRRC) that indicate that in several species, there’s the male that mates via “domination” and one that does it by “being subtle” (or climbing thru the back window, as it were). The pack system works if the animals are related, but it does not necessarily require parent/child relationships for all members. Most of the studies on wolves are done on islands (Isle Royale, Elsemere) or in pretty confined/restricted areas where “normal” behavior is difficult (Italy, Spain). The YNP wolves may be more “typical” than we think.
Peggy Richter.
A Casanova wolf must be a contradict to Romeo, another black wolf about which you Scott have written, too.
As his name suggest, he seemed to have mated only once, and when that bitch, the love of his life, was killed by a car, he looked for company among domesticated dogs.
These sorts of mating strategies probably occur in all wolf populations but because breeding females get better access to dens and the resources of the pack, so the pups from those multiple breeders don’t exist everywhere.
It is simply a strategy to get more breeding opportunities.
when times are “good” — there are plenty of resources to go around and more than one den site in a territory, I would expect that more breeding would occur. When the resources are marginal, or other challenges make it difficult for a pack to support more than one litter, I would expect that less breeding would occur and that most of it would be the Alpha pair. Keep in mind that that the pack system “works” because even if subordinate pack members don’t breed, their DNA does “go forward” via the breeding of parents or siblings. In the “black wolf” documentary, the wolf in question didn’t “help” raise the first litters as much as normal (although again, IIRC, he did do some help). When his brother took over a pack and he became a subordinate, he did help, he just wasn’t the “Alpha” (in fact, during that phase, the strategy reminded me of lions who will often have brothers take over a pride — two males being better able to defend a pride than a single male can). And at the end, he was the Alpha and did some breeding –but had “Casanovas” in his pack as well — but if these were breeding his daughters, again, his DNA was going “forward”.
We tend to view animals (and ourselves) in a black and white format — the animal is “pair bonded” or not. We tend to find it confusing that an animal can “pair bond” but “not always”.
Speculating, it may be that “casanova” wolves were more likely than any other kind to have been the sires of the early “wolves becoming dogs” — simply because both the wandering and the “love em and leave em” behavior would be more likely than the other strategies to leave offspring in those early camps. Certainly Humans tend to encourage a Casanova (or even a Don Juan) behavior — which explains it being so much more common in dogs.
Peggy Richter.
What is interesting is that there have been studies of wolves that have been killed in either Canada or Alaska.
All bitches over the age of two have used uteri.
That means they all get bred. It’s just that normal packs don’t have enough food to feed more than one litter.
I got to see this documentary too–excellent! Having wolves in Yellowstone where they habituate somewhat to humans and go about their natural behaviour has been a godsend for documenting wolf behaviour! And such stories as this individual wolf’s just goes to show that trying to lump all animals of a species in one narrow behavioural category is very inaccurate(though popular with scientists who want THEIR study to dominate!)–animals like wolves are SUCH individuals, living in very different environments with a multitude of varying things to adapt to, it is scientific blindness to assume ALL wolves do such-and-such because that’s what was noted in one brief, limited scientific study! That’s why, when studying animals, the most that you can say is, well, these animals are doing this in this environment at this time, but that may not(in fact usually DOES NOT) hold for all individuals, especially in totally different environments. And as always, THINGS CHANGE!
The “casanova” wolves were obviously quite prevelent in earlier, pioneer times–quite a lot of accounts of them hanging about forts and Indian camps and occaisionally mating with dog bitches. And they were probably just like this individual, who was unattached to a pack, and used the prescence of humans(the roadways in this documentary’s case) as a refuge when pack members attacked and tried to drive him off–without this form of refuge he very likely would have been killed or had to continue dispersing much farther. This is the seeming contradiction when people vehemently say wild wolves and dogs NEVER breed, as wolves quickly kill dogs at any given opportunity, so the old stories of Eskimos and Indians tying out bitches in heat for wolves to breed are myths. An established pack of wolves, aggressive to any canine interlopers, certainly do usually kill any dog they come across, but these young male dispersing and unattached “casanova” wolves, the ones most likely to be hanging around human settlements in the first place, most certainly do breed with dogs, and I’m sure the old time Eskimos and Indians knew this very well and utilized this process quite purposefully when they were practically trying to inject some genetic diversity and hardiness in their sled/toboggan and travois dogs.
I have an account somewhere of wolves mating with a trapper’s dogs in what is now North Dakota.
And there are also accounts of using bitches in heat to kill wolves. Let the dog and wolf mate, then kill the wolf while they are tied.
And one reason people studying wolves may not have realized that more subordinate females were breeding, is that they had to do it away from the pack and the observation of the Alpha animals(therefore were much more secretive and less likely to be observed), and then if they DID whelp a litter, it likely was “kidnapped” by the dominant female and joined her litter(why some wolf litters appear larger than average)–or possibly the victims of infanticide–African Wild Dogs have been well documented doing this. And AFD’s, since they have no set, limited breeding season like Northern wolves, it is often VERY obvious when more than one litter is combined, as the pups will often be quite different in size and age, something that is not going to be as noticable in Northern wolves. Wolves are also well known, in captivity and in the wild, to quickly adopt ANY wolf pup they find–even going so far as to stealing rival packs’ pups!–and raising them as their own. Pups up to 3 months old or so, that is. So, some of the “auntie” wolves seen tending the Alpha female’s litter may sometimes actually be tending a few of their own pups as well! Modern DNA testing may reveal more of this in studies in the future…….
Whenever a non-pair bonded wolf of African wild dog gives birth, she tends to do so after the pair-bonded breeding female.
From what I’ve read about in Lycaon, the pair-bonded female does steal the other’s puppies, but her puppies are already a week or two older than the other bitch’s. That means that the puppies from the extra breeding bitch are less likely to survive.
In dingoes and some domestic dogs, the higher status bitches sometimes kill the puppies of the lower status bitch. This happened in Elizabeth Marshall Thomas’s The Hidden Life of Dogs.
It’s all variable and complex– exactly what you’d expect from these animals.
[…] their natal packs, new wild blood would also be brought in, and through wild wolves engaging in the Casanova strategy for reproduction, even more wild blood would be brought […]
[…] dogs, for whatever reason, don’t seem to be as particular about their mates, and thus, it has been easier to […]
[…] that have not yet found a partner are well-known to solicit male wolves from other packs, as well as male wolves that don’t belong to any particular pack. In Italy, these unattached females are known to solicit male […]
[…] story of a “Casanova wolf” whose mating strategy was more similar to that of a domestic […]
[…] there are wolves that use another strategy for reproduction. These are the so-called “Casanova wolves” or “lone rangers.” These are male wolves that leave their parents’ […]
[…] which stymies their recolonization of much of their former range, and in Yellowstone, at least one “Casanova wolf,” a bachelor wolf that mated only with the non pair-bonded wolves in established packs, used […]