Because the beaver isn't just an animal; it's an ecosystem!

Tag: Beaver monogamy


Well yesterday was fun, with little messages of encouragement for our 10th year  from folks around the globe. Now it’s time to get back to work. You know what they say, before anniversaries “Chop  wood, carry water“, and after anniversaries”Chop wood carry water“. Or something like that.

Here are two articles that deserve our attention. I’ll start with the grating one first. Why is it every article written about Peter Busher annoys me more than it interests me? Over the years I have come to think he basically knows his beavers, but he honestly doesn’t seem to like them very much.

The Secret Sex Lives of Beavers

The population boom can raise alarms in communities. Beavers are often viewed as a nuisance, causing millions of dollars in damage each year by chewing fences, trees, and decks. They build dams, which leads to flooding of homes, crops, and railroads.

But some behaviors can be beneficial, says Peter Busher, a College of General Studies professor of natural sciences and mathematics and chair of the division. Beaver dam building expands wetlands, whose functions include filtering toxins from water, supporting biodiversity, and mitigating floods.

Peter Busher poses with beaver captured for analysis

Busher has been studying beavers for four decades and was the first person to track the animals by tagging them with radio transmitters. He does his research in the Quabbin Reservation in Central Massachusetts, where 150 to 300 beavers con­stitute the nation’s longest-studied population, says Busher. Hoping to learn how humans can better coexist with beaver populations, he examines mating habits, birthrates, group structure, and how the animals migrate from one area to another. His findings could inform deci­sions about how communities respond to beaver activity and manage the animal’s population, both in Massachusetts and across the country.

Although beavers are among only 3 percent of mammals that are socially monogamous, raising their young exclusively with one partner, researchers do not know much about their pairing behavior. Do the parents also mate with other beavers and raise a mixed brood, or are they sexually exclusive? Busher wants to find out. He suspects that genetically monogamous beaver populations—those that tend to mate with one partner—increase more slowly and may stay in an area longer. If one of these populations were removed because of nuisance activity, he says, the area would likely be free of beavers for a while. But if the population were more promiscuous, new beavers could move into the area at any time; communities would then need to develop a long-term animal removal plan.

Promiscuous beavers? Honestly? Is that honestly what you think? Who thinks like that? Have you looked at every OTHER variable in their habitat that might differ between various beavers to rule out that food availability, or population, or stream gradient and prove that these it doesn’t influence which beaver are promiscuous and which aren’t? I’m sure, as a scientist, you would do ALL THAT before LEAPING to the assumption that DNA is responsible. I mean this is almost like race research.

How much trouble would you be in if you were posing that certain ethnicitys were more promiscuous?

The best research I have read on the topic described beavers as “opportunistic monogomists” – meaning if the right conditions happened to arise they would take advantage of them and mate outside the pair bond, and if they never arose it would be mostly okay with it and get on with the business of taking care of the family. I remember being amused when Rickipedia commented that this was pretty much the same for most male humans.

But Dr. Busher is trying to prove that it’s a beavers genes that make him roam. So that those prolific beavers we can kill more, and the faithful homebodies we can work with.

Are you sure you teach in Massachusetts? Because this theory is starting to sound positively republican to me!


The article that really interested me today comes from the irreplaceable George Monbiot and discusses the use of better language about ecology to capture public interest. Rusty of Napa sent it my way and I’m glad he did.

Forget ‘the environment’: we need new words to convey life’s wonders

If Moses had promised the Israelites a land flowing with mammary secretions and insect vomit, would they have followed him into Canaan? Though this means milk and honey, I doubt it would have inspired them.

So why do we use such language to describe the natural wonders of the world? There are examples everywhere, but I will illustrate the problem with a few from the UK. On land, places in which nature is protected are called “sites of special scientific interest”. At sea, they are labelled “no-take zones” or “reference areas”. Had you set out to estrange people from the living world, you could scarcely have done better.

The catastrophic failure by ecologists to listen to what cognitive linguists and social psychologists have been telling them has led to the worst framing of all: “natural capital”. This term informs us that nature is subordinate to the human economy, and loses its value when it cannot be measured by money. It leads almost inexorably to the claim made by the government agency Natural England: “The critical role of a properly functioning natural environment is delivering economic prosperity.”

I’m fully on board with the need to use language that enlivens and engages us rather than regulates our attention. But sometimes we are talking to politicians or biologists and need to convince them, and we think that kind of language carries more sway? Maybe it doesn’t. Maybe the only thing that matters to decision makers is what we celebrated yesterday: public pressure and votes. So engaging the public is more important than sounding objective.

This is my FAVORITE part.

On Sunday evening, I went to see the beavers that have begun to repopulate the river Otter in Devon. I joined the people quietly processing up the bank to their lodge. The friend I walked with commented: “It’s like a pilgrimage, isn’t it?” When we arrived at the beaver lodge, we found a crowd standing in total silence under the trees. When first a kingfisher appeared, then a beaver, you could read the enchantment and delight in every face.

Our awe of nature, and the silence we must observe when we watch wild animals, hints, I believe, at the origins of religion.

Something about that sentence feels very, very true for this woman who spent so many years in the company of beavers. (Not that we were silent the whole time.) Our beavers had train whistles and garbage trucks to get used to, and could handle a little talking. But there was definitely awed silence at times. Like when kits emerged or when an uncommon behavior was scene.

And it sure felt like the very best parts of church to me.

if we called protected areas “places of natural wonder”, we would not only speak to people’s love of nature, but also establish an aspiration that conveys what they ought to be. Let’s stop using the word environment, and use terms such as “living planet” and “natural world” instead, as they allow us to form a picture of what we are describing. Let’s abandon the term climate change and start saying “climate breakdown”. Instead of extinction, let’s adopt the word promoted by the lawyer Polly Higgins: ecocide.

We are blessed with a wealth of nature and a wealth of language. Let us bring them together and use one to defend the other.

Thank you, George for another beautiful column. I’m envious of the people who got to walk alongside you on the way to see those special Devon beavers. We very rarely feel reverence for what we consume or eliminate as inconvenient. But I have seen it time again on children’s faces watching our beavers.

Maybe its reverence, more than science, that protects nature.


And makes us rather bear those ills we have
Than fly to others that we know not of
Hamlet Act III: Scene 1

Apparently I’m not the only one who uses this ominous threat when people are thinking about getting rid of the beavers on their land. Deal with the beavers you have, I always say, because the one’s that come next might be even more problematic. Meanwhile Dr. Peter Busher at BU is busy researching it.

Beavers vs. Humans

CGS prof studies the socially monogamous mammals

Peter Busher has been studying beavers for four decades. A College of General Studies professor and division chair of natural sciences and mathematics [at Boston University], Busher was the first person to track the animals by tagging them with radio transmitters. He examines beaver population dynamics and behavior, including mating habits, birthrates, group structure, and how the animals migrate from one area to another. His findings could inform decisions about how communities respond to beaver activity and manage the animal’s populations, both in Massachusetts and across the country.

Busher says an influx of beavers in a community can raise alarms, causing heated discussions about whether trapping should be broadened to control the population. But he points out that some behaviors can be beneficial. Beaver dam building expands the wetlands, whose functions include filtering toxins from water, supporting biodiversity, and mitigating floods. (Busher notes that wetlands loss contributed to the destruction wrought by Hurricane Katrina in New Orleans.)

It’s important to understand how the animal’s population naturally develops, Busher says, and how its family dynamics work. Beavers are territorial, live in family groups, and are selective about which sites they inhabit permanently. These factors mean their populations spike when they move into a new area, but generally drop and stabilize over time.

Knowledge of beavers’ mating habits—which can vary based on their environment—could influence how communities manage the rodents and their “nuisance activity.” Although beavers are known to be among only 3 percent of mammals that are “socially monogamous,” raising their young exclusively with one partner, researchers do not know much about their pairing behavior. Do the parents also mate with other beavers and raise a mixed brood, or are they sexually exclusive? Busher wants to find out.

He believes genetically monogamous beaver populations—those that tend to mate with one partner—increase more slowly and may stay in an area longer. If one of these populations were removed because of nuisance activity, he says, the area would likely be free of beavers for a while. But if the population were more promiscuous, new beavers could move into the area at any time; communities would need to develop a long-term animal removal plan.

Hats off to Dr. Busher. Even I wouldn’t have the cajones to make a threat like that. “If you kill these beavers the next ones you get might have more babies and reproduce even more!”  Last I heard research was saying that our beavers were ‘opportunistic monogomists’ and Castor Fiber was loyal and true. Apparently, now he thinks it has to do with individual variables which is pretty fascinating.

All I can say is this gives me memories of Obi Wan.

Go read the entire article and think about our beavers who stayed in on place for 9 years and appeared pretty loyal. We had the unique remarriage after mom died and I wouldn’t say the birth rate changed much with a new partner. 4,4,0,3,1,3,1,4. But what do I know. I never tagged beavers. I just watched them.


 

OLYMPUS DIGITAL CAMERA

Now wish me positive vibes because I’m off for my very last  day. Tomorrow we are moving out of the office and I’ll be a retired child psychologist. I’ll be donating my toy collection to the agency where I completed my post doc and the next four days have all the tightly planned synchronized moves of a beaver festival. I’m bracing myself for the personal and clinical chaos that may ensue in the new year. But I’m trusting that I will still find many meaningful ways to contribute!


Canadians too. Apparently only the european beaver knows how to make a marriage work.

CaptureBeavers pair up for life and never cheat

European beavers are truly monogamous, but the same cannot be said of their North American counterparts

Most animals aren’t the marrying kind. Less than five percent are believed to pair together for life, and even if they do stay together they do plenty of cheating.  But not European beavers. Not only do they pair up for life, a new genetic analysis shows that they are faithful to each other.

 A team led by Pavel Munclinger from Charles University in Prague, Czech Republic took samples from several European beaver colonies living in the Kirov region of Russia. They then analysed the genetic relationships among family groups.

 In every colony, all the offspring belonged to both of the parents. None of them had been fathered by males from elsewhere.

The same cannot be said for their American counterparts. North American beavers are known to mate with beavers other than their bonded partners.

 They cheat a lot. In 2008, researchers discovered that the “father” of a pair of young was unrelated to at least one of them about half of the time.

I knew all this monogamy business was a smokescreen! How many times have I been watching our beavers and seen mom bat her come-hither eyes at the nearest woody offering! (There’s a reason the word beaver has another meaning ya know…) We read this particular research they’re referring too back in 2008 in preparation for our historic prevalence paper. The authors referred to it as “opportunistic monogomy” and Rickipedia quipped that the term describes most males of the human species too. Ha.

Cheating does have its advantages. If a mother mates with a healthier male than her main partner, she can pass better genes onto her young.

 But there are also advantages to staying loyal. “Genetic monogamy lowers the risk of parasite transmission,” says Munclinger.

 “It also lowers the risk of partner desertion, which is very important in species with extensive parental care of both sexes.”

 Staying faithful seems to serve the European beavers well. Their populations have been climbing in areas of the UK where they have been reintroduced.

It’s good that this news is being lauded in the British Press. They need another reason to like beavers and being told ‘theirs are better’ is a great way to convince the holdouts. In  a more sober consideration you have to wonder whether population density matters. And whether  having very little competition affects how faithful beavers chose to be. Most of Europe is as crammed with beaver as it is with people now and those beavers don’t cheat apparently. Our population is decimated and our beavers mate with anything they can get. Maybe the facts are related. Didn’t a pair from the (no beavers for 500 years) Scottish beaver trial hook up with other beavers?

We  American beaver-lovers will just continue being content with their slutty ways until the population gets fuller, I guess.

And in case you need more praises sung for beavers, here’s a fun reminder from Fairbanks Alaska

Rodents are remarkable creatures, not pests

If you only think of rodents as pests, you are missing out. One reason these animals are misunderstood is because there are so many of them. More, in fact, than any other kind of mammal, but they play an important role in the ecosystem.“

 Some of these rodents are referred to by ecologists as indicator species,” Nations says, “because they indicate the health of an ecosystem.”

 Another example is the role that beavers play in creating wetlands that are used by many bird species. Beaver ponds also can be convenient places to spot moose and muskrats are known to take up residence in beaver lodges, as well.

Theresa Baker ends the nice article by suggesting kids build a ‘rodent collection’ in their home, you know a clay porcupine with toothpick spines etc. Good idea, and I would definitely include one of these:

peanuta

Inspired by the fact that a beaver kit is shaped exactly like a peanut. Peppercorn nose, lentil ears, black mustard seed eyes and pumpkin seed tail set in macaroni noodle, Worth A Dam original

 

 

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