Some food for thought ...
A recent study in the Greater Yellowstone ecosystem connects declines in native cutthroat populations (due to invasive lake trout) to decreases in elk calf recruitment and overall elk populations. Why? The stream-spawning cutthroats, now largely gone, are no longer available to grizzly bears, and the latter have turned to elk calves as an alternate food source.
(Photo: Jason Bechtel)
It's an interdependent system, of which we, humans, are part.
A recent study in the Greater Yellowstone ecosystem connects declines in native cutthroat populations (due to invasive lake trout) to decreases in elk calf recruitment and overall elk populations. Why? The stream-spawning cutthroats, now largely gone, are no longer available to grizzly bears, and the latter have turned to elk calves as an alternate food source.
It's an interdependent system, of which we, humans, are part.
And here's the bottom line: The disruption of this aquatic–terrestrial linkage could permanently alter native species interactions in YNP.
connecting link: http://rspb.royalsocietypublishing.org/content/280/1762/20130870.short
And here in southern Alberta?
We in southern AB might wonder what the colossal reductions in native cutthroat and bull trout populations (each a headwaters stream spawner) have done to alter terrestrial outcomes that we never imagined to be interconnected.
And, similarly, and again based on studies in Yellowstone, we might wonder what white pine blister rust (killing native whitebark pines, limber pines and this province's relatively few western white pines) might be doing to further reduce a vital food source for foraging grizzlies.
It's all connected. So are we.
We in southern AB might wonder what the colossal reductions in native cutthroat and bull trout populations (each a headwaters stream spawner) have done to alter terrestrial outcomes that we never imagined to be interconnected.
And, similarly, and again based on studies in Yellowstone, we might wonder what white pine blister rust (killing native whitebark pines, limber pines and this province's relatively few western white pines) might be doing to further reduce a vital food source for foraging grizzlies.
It's all connected. So are we.
Thanks for this insight into these systems, David! The grizzlies have all woken up and are beginning to forage. Let's hope that they find some appropriate breakfast before having to wander far on an empty stomach.
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