Discussion



The pikas on Mt. Shasta occur in several, sometimes widely scattered, localities. In my visits to the sites I occasionally hear or see more than one pika. It is known that Ochotona princeps lives solitary in territories, often alternating male and female. Still, they do not seem to be numerous. Perhaps most amazing is the fact that I could find pikas in the original localities described in 1898. Over one hundred years later and the pikas have survived in the same talus slopes. It is also amazing that pikas are living as low as 4,500' in lava on the north side of the mountain. These environments are hot in the summer daytime, but have deep fissures that are cool. It is to be noted that the glaciers on Mt. Shasta (though variable throughout the years) were thought to be growing, but since the early 21st century are now known to be shrinking. Although this study found pikas in virutally all the historic pika sites, a continued trend of warming is expected to force both pikas and plants upslope, most likely with challenging effects.

There are problems studying the moment-in-time distribution of pika populations and the inference of population trends. Specificaly, the discovery, occupation and abadonment of sites, the duration of occupancy and interactions with predators and non-biological stresses all would need to be much better understood to be confident in such an analysis. At this point in time, 2020, it would seem that the pika populations on Mount Shasta are numerous and widely scattered over the south-west and west side of the mountain and are in no danger of extirpation.

I have heard pikas calling and giving response several times during my investigations, but the pikas on Mt. Shasta are, as noticed in 1898, much less noisy than their nearby cousins. I have hunted for and found pikas in the Lava Beds National Monument, Mt. Lassen National Park and in Yosemite, and in all cases, the pikas were rather noisy during my visit--at least as compared to those on Mt. Shasta. Another curious note: I haven't found a "haystack" which is so typical of the species. This rarity of haystacks was also noted in the 1898 report. I can only assume that at least some of their haystacks are underground and the others are just not being noticed. Although I generally am not looking for haystacks, in other places the presence of a haystack is the first sign that pikas are around and they seem curiously absent.



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