Strange sounds in the night

I recently returned from an 11-day road trip through central and southern Oregon.  I traveled from Steen’s Mountain in the east, across to the central Cascades, to the coast and then south until I ran out of Oregon, back to the Cascades in southern Oregon, and home via Mts. Shasta and Lassen.  It was more of a sightseeing journey than a recording trip, with the critters pretty quiet as they prepare for winter.  I had hope to record some elk bugling, but in spite of numerous road signs proclaiming ELK, I saw very little sign of them and only observed one group of elk – a bull and his harem – alongside a busy highway on the Dean Creek Elk Viewing Area.  I heard not a single bugle, yelp, bark, or hoofbeat.  By the time I left the state I was convinced most of the elk in Oregon were imaginary.

It was a beautiful trip, however, with the blue skies (only 2 smoky days!) and fall colors.  I was especially enthralled with the Cascades, with their incredible volcanic scenery and huge, dark forests.  We (the dog and I) managed to get in some really nice hikes to lakes and waterfalls.

I found some good camping in the Cascades also.  The first place we camped at was not much more than a roadside pull-off, but it did allow camping.  It was deep conifer forest, with a lovely quiet to it.  Other campers were there the first night I camped there, and there was enough traffic on the road, so I did not set out my recording equipment (still hoping for elk, or maybe owls).  I returned a couple of days later to do some recording.  It had rained earlier in the day, and was still cloudy as it got dark.  I set up a recorder and a couple of mics near a spring, up the hill from the campground, and left the recorder to run all night on its own.  A couple of hours later, it started raining, so I grabbed my rain gear and a flashlight, and stumbled my way up the hill and recovered the recording equipment.   I didn’t get a chance to listen to the recording until I returned home, but when I did, I heard the following strange sounds:

I had to listen to it several times and very carefully before I figured out what it was.  The first clues where the humming that preceded both “shouts.”  The second was the sounds of walking/crashing through the vegetation as the animals passed by the microphone.  Both of these are consistent with black bear (Ursus americanus).  Black bears have a rather extensive vocal repertoire;  Dr. Lynn Rogers, of the North American Bear Center, has similar recordings on his website.   If you listen carefully, you can hear that the humming remains on the left, while the “shouter” moves from left to right (you might need headphones for this).  I suspect that it was a momma with a couple of cubs, and the shouts were yells between cubs (sounds like, “get out of my face!” to me).   I’ve recorded black bear mommas and cubs before, but the sounds were quiet different.  It’s certainly understandable why bigfoot (AKA sasquatch) is such an omnipresent mascot in the area!

Could this have been bigfoot?  In a way, yes.  So far, most credible evidence from bigfoot sightings has come back to black bear.  Genetic analysis of hair samples found at supposed bigfoot encounters came back as black bear, raccoons, wolves and livestock (Sykes et al. 2014).  Computer niche analysis of bigfoot sightings overlapped almost perfectly with black bear habitat niches (Lozier et al. 2009).  Even Kim Cabrera, certified animal tracker and search-and-rescue tracker (www.bear-tracker.com), suspects that what people identify as bigfoot are actually bears:  “Having lived in ‘bigfoot country’ for almost 30 years, and been tracking in these forests the entire time, I can say I’ve never seen any evidence that anything but bears are out there in the forest. I have been asked to identify various photos showing “bigfoot” sign, but all have been attributable to bears. Mostly the scrapes on trees and bent over saplings, which bears love to do.”  In other words, although bigfoot fans and other cryptozoologists will vehemently deny this, bigfoot = black bear, most of the time.

I was contacted awhile ago on Wild Mountain Echoes Facebook page by a guy looking for guidance in setting up an array of ultrasonic microphones.  When I enquired “why?”, he said it was to detect bigfoot (because everyone knows that the reason no one has heard bigfoot is because they communicate in frequencies we can’t hear).  This is a little hard to swallow on theoretical grounds.  The bigger the animal, generally the lower the frequencies they produce (Peters and Wozencraft 1989).  Elephants, our largest land mammal, makes some sounds so low we can’t hear them (infrasound).  Some larger animals, such as mountain lions, do produce ultrasonic calls when talking to their cubs, but no large mammals are known to exclusively use ultrasound, which is usually defined as above the usual hearing range of young humans, 20 Hz to 20,000 Hz.  An array of ultrasonic microphones would reveal some interesting sounds of insects, mice, and bats (and are being deployed for just those purposes), but is very unlikely to reveal ultrasonic communications by bigfoot.  Very little is known about hearing and vocalization range in black bears, in spite of how common and vocal they are, but no ultrasonic signals have been reported.  Among primates (to which bigfoot is erroneously ascribed), only one, the tiny Philippine tarsier, routinely uses ultrasound for communication (Ramsier et al. 2012).  Ultrasonic calls attenuate (lessen) very quickly in a forested environment, so are only useful for very close communication or echolocation.  For long distance communication in a wooded environment, frequencies at or below 1,000 Hz are better (Peters and Wozencraft 1989).  Most bear communication occurs in this range, including the “shouts” in the above recording.

But those weren’t the only strange sounds I heard in the Cascades.  After visiting the coast, I stopped at a campground in the forest west of Klamath Falls.  I had the small campground, in a forest of huge firs next to a small stream, to myself.  There was a frog slowly croaking, and I was still hoping for owl calls, so I set up my mics to record between the stream and the forest.  I ran the mic cable into a recorder in the car, as I often do, and monitored the sound through ear buds as I read a book.  As I was almost lulled into sleep by the rhythmic croaking of the frog (later identified as a Sierran Tree Frog by Lang Elliot), I started to hear a distant humming sound.  It slowly got closer and closer.  Then I was startled awake by this horrific screeching coming right toward me (listen all the way to the end):

I was certain I was under attack!  I lay awake for a considerable time after that, listening to make sure it was gone.  Meanwhile, something was dropping heavy fir-cone bombs all around me and the humming sound was getting closer and closer.  After I calmed down a little, I thought about the squawk attack and what could have made it, and was pretty sure I heard a Great Blue Heron.  I was able to confirm it the next day with my Audubon birds app.  As the humming got closer and closer it resolved itself into a bunch of cow bells.  In the morning, I tracked down the bomb-dropper, and it turned out to be a Douglas’ squirrel.  But I never did hear any owls or elk.  Sigh.

Lozier, J.D., P. Aniello, and M.J. Hickerson. 2009.  Predicting the distribution of sasquatch in western North America: anything goes with ecological niche modelling.  J. Biogeography (https://doi.org/10.1111/j.1365-2699.2009.02152x).

Peters, G. and W.C. Wozencraft. 1989. Acoustic communication by fissiped carnivores.  Pp. 14-56 in Carnivore Behavior, Ecology, and Evolution.  Ed. by J.L. Gittleman. Cornell University Press, Ithaca, NY.

Ramsier et al. 2012. Primate communication in pure ultrasound.  Biol. Lett. 2012 8 508-511; DOI: 10.1098/rsbl.2011.1149.
 (http://rsbl.royalsocietypublishing.org/content/8/4/508).

Sykes, B.C.. R.A. Mullis, C. Hagenmuller, T.W. Melton, and M. Sarton. 2014. Genetic analysis of hair samples attributed to yeti, bigfoot and other anomalous primates. Proc. Biol. Soc.B. 281: 20140161 (http://dx.doi.org/10.1098/rspb.2014.0161)

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