This important story on the Mexican wolves is from Wild Again, the Sinapu blog. The story has also been in a number of newspapers the last day or so.
Conservationists Request Suspension of Mexican Wolf-Killing “Predator Control” Policy
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Conservationists Request Suspension of Mexican Wolf-Killing “Predator Control” Policy
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Id just like to ask a question here — I know it will probably start a “feces storm” but I’d like to ask it anyway.
How come the genetics of the “Mexican” wolf are held in such high esteem when the genetics of the wolves that were introduced in the Northwest were deemed OK??
The reading that I can do does point out that, indeed, the Mexican wolf is considered a different “subtype” than other wolves. BUT, when those same books and references point out a different subtype of wolf in the Northwest they are considered “obsolete science”??
Seems kinda goofy.
Layton (aka – Trex (I kinda like it!!)) ;^)
All of the the Mexican wolves are from the last 7 (or was it 8?) of their kind. They were captured and maintained as captive wolves until the time they could be restored to the wild.
As a result of the small source population, their genetic diversity is problematic. Inbreeding can be a severe problem, and so the captive breeding of this population has been done with the utmost care and forethought to maximize what genetic diversity there is. Even so, it appeared to me that about 20% of original diversity of the source wolves has already been lost.
The wolves in Idaho, Montana, and Wyoming have highly diverse genetics.
At our recent North American wolf conference, a UCLA genetics researcher presented data on these wolves, including every Yellowstone Park wolf pack, and found them to be genetically excellent. Moreover, these wolves have maintained outbreeding on their own.
She did warn, however, that within a half century, inbreeding will become a problem in the Park unless wolves from outside the Park begin to migrate in. So far, Yellowstone has been a source of wolves, not a destination for new wolves.
None of this has anything to do with what you termed “subtypes.”
From DesertUSA (http://www.desertusa.com/mag98/mar/papr/du_mexwolf.html): The Mexican Wolf is the rarest, southernmost and most genetically distinct sub-species of the Gray Wolf in North America. It is also one of the smallest sub-species, reaching an overall length no greater than 4.5 feet and a height maximum of about 32 inches.
I imagine that the smaller body size better suits the Lobo’s warmer habitat (and somewhat smaller prey), as these were the animals that traversed the deserts and the islands in the sky where big game is somewhat less plentiful.
Nice, but no one seems to answer the question — how come sub-species (my bad using “subtype”) IS considered when related to the Mexican wolves but was NOT considered when the introduction was done in the Northwest??
Layton (aka Trex)
What was there to consider? The original elimination of wolves from the NW United States pushed the wolves back into Canada–the original NW and Canadian populations were connected by geography and ecology. Heck, the occasionally wolf was already infiltrating the NW from Canada when wolves were being reintroduced to Yellowstone.
It’s also worth noting that it isn’t always entirely clear how many subspecies of gray wolf there really were in North America. It’s fairly clear that Mexican wolves are different–they’re significantly smaller, fairly distinct genetically, and inhabit a different landscape. There is a much smaller distinction between wolves from western Canada and the original population of the NW. There was likely significant gene flow between those wolves in say, the Yellowstone area and those in southern Alberta and British Columbia.
Not long ago, wolves (and every living organisms) were broken into species and sub-species by physical characteristics such as size, proportion color, and by geography (where they live). Now more emphasis is placed on genetics. A very high percentage of mammal genes are the same. Individual species have even a higher percentage – dogs, wolves, foxes and coyotes are very closely related genetically. Because wolves are travelers, they spread their genes over large areas so most wolves are even more closely related genetically. That’s why most people think there are only 5 or 6 sub-species of wolves instead of 24 or more. That’s why wolves in Canada are the same as those across the border in Yellowstone. If you take some blood and run the tests you would have a hard time figuring out which wolf is from Canada and which is from Yellowstone. Or if you like, a wolf in Sasketchewan and British Columbia.
If you compare a Mexican wolf to those from the north it would be easier to discriminate because Mexican wolves, as a group, are significantly genetically different.
Why? Probably because intermingling between the two populations was less frequent due to geographic constraints. Or it could be that the two migrated to their present location at different times in the past. At any rate, the genetic difference has physically expressed in Mexican wolves in several ways the most obvious being they are somewhat smaller.
That, believe it or not is the boiled down version. There are many scientific article on this subject – most of which are incredibly hard to read.
Nice explanation Chris. That question has been asked and answered numerous times on this blog, and anyone with just a little bit of effort could answer it themselves with barely a afternoon of research. I believe that the answer is just not accepted and some just keep trying to make 2+2=5. The short answer of course is that the subspecies question was considered and the same subspecies was reintroduced as was present historicaly.
Thanks Jeff E
Yes, thanks Chris — certainly a good explanation.
Advancement in genetics is changing many classifications that once seemed reasonable. It think it’s most exciting!