Bringing us to the question that led to this post: what's wrong with this picture?
Unless you're a friend in-the-know, or a close reader of my Mono-specific mumblings, the answer may not be obvious. Because it lies in what's missing - a GPS tracking collar.
As mentioned in past posts, to help rebuild the endangered Sierra Nevada Bighorn Sheep population, pretty much all the California lions from Bodie to Bishop and beyond have GPS collars, are actively monitored, and even "herded" away from the sheep. Courtesy of Cal Fish & Game.
But lions in Nevada, just 30 miles away from my Mono Basin survey site, don't have collars.
Hmmmm... 30 miles is much less than 60 miles or 100 or 663...
About 1/2 of young female lions disperse. But even then, females don't generally disperse as far, since they tend to have smaller home ranges that often overlap with their neighbors. I.e., lady lions are more social and friendly. Shocker, that.
Male lions, however, are "obligate dispersers" - which in biogeek-speak and lionese means they gotta hit the road or Dad (and Mum) will kick their lazy ass something fierce. And continuously. The parents just don't want the competition. Plus, it helps with gene dispersal.
And as we can see from this second photo, our collarless stray does happen to be a boy-o:
While GPS collars are amazingly useful for tracking individual and localized transit patterns - genetic sampling is starting to reveal even bigger animal-picture details, such as the macro movements over generational time and much grander topographies.
A key aspect of these large-scale genetic flows is their "source-sink dynamics." Sources being fonts of species supply, and sinks being sponges of population demand. The typical causes of sources, sinks and patterns between are the usual suspects: food and water availability, habitat quality, predation and hunting pressure, land development, topographic barriers, etc.
However, there are anomalies that counter good source-sink edu-guesses. The eastern Sierra Nevada seems to be one. Researchers at the University of Nevada that tested genetic samples of 739 lions from Nevada and eastern CA had predicted the Sierra would be a source of lions, since there's more cats there than in the Nevada ranges next door. I.e., their reasonable theory was that lions would disperse towards Nevada's open, more easily occupied territories.
But the data are showing the opposite - more lions are coming to CA from NV than going the other way. Appears pumas prefer to live (and can live) in higher densities in the Sierra, where water and deer are more plentiful (and yes, no one hunts them), over the spacious, yet arid mountains and canyons of Nevada's west-side. Queue music and finger-snapping.
So, if you are a migrant from Nevada - welcome to Cali, young cougar dude.
Paradise found.
But ya better get ready bro - the Bighorn collar-crew is looking for you.
==
Ooh, ooh, ooh, ooh
Ooh, ooh, ooh, ooh
Black and orange stray cat sitting on a fence
Ain't got enough dough to pay the rent
I'm flat broke but I don't care
I strut right by with my tail in the air
Stray cat strut, well, I'm a ladies cat
I'm a feline Casanova, hey man that's that
Get a shoe thrown at me from a mean old man
Get my dinner from a garbage can
I don't bother chasing mice around
I slink down the alley, looking for a fight
Howling to the moonlight on a hot summer night
Singing the blues while the lady cats cry
"Wow stray cat, you're a real gone guy
I wish I could be as carefree and wild
but I got cat class and I got cat style"
- Stray Cats, "Stray Cat Strut"
====
References:
- A. Andreasen, K. Stewart, W. Longland, J. Beckmann, M. Forister - Molecular Ecology, Aug 2012 - Identification of source-sink dynamics in mountain lions of the Great Basin
- Our Amazing Planet - Mountain Lions Migrating West to California
- KQED - Truly CA - Counting Sheep
- California Department of Fish & Game - Bighorn Sheep Recovery Program
- Nature of a Man (this blog) - Smelly Cat
- Nature of a Man (this blog) - Always Put Collars on Your Kitties
- Nature of a Man (this blog) - posts on cam trapping the Mono Basin
- Stray Cats - Greatest Hits, including Stray Cat Strut
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