MARCH 8th 2008 - LYNX !
I recently visited one of my regular sites in the Jura about 3 km NW of Arzier. I had last been there on 17th Feb and recorded a Pygmy Owl (Glaucidium passerinum) which I was hoping to get a better recording of. On that same day I had also recorded a pair of foxes and a Roe deer alarm call. I call this place "Les Frasses Valley" after a nearby farm.
On March 8th between 0630h and 0900h I walked slowly to the head of the valley recording various sounds, I then sat quietly for a while, no other people were around. With no sound of my owl I decided to give up, as I was descending the valley back to Arzier I suddenly heard a loud "scream" which came from within the forest to the east of me. I was walking along the edge of the forest, about 10m clear of the trees in the pasture, the call came from within the forest and my guess is that it was about 200m away from me. I was able to get about 58 secs of sound before it stopped calling:
[NOTE: This recording has been edited and frequencies below 600Kz suppressed slightly to reduce the interference from a nearby aircraft. The frequency of the call and the rhythm of calling are as recorded in the field.]
A sonogram of 4 calls is shown below:
FIGURE 1: Sonogram of 4 calls of European Lynx (Lynx lynx), horizontal axis time in secs, vertical axis Khz. The call starts at about 900Hz rising to a peak of about 1.6 Khz before tailing off back down to about 800 Hz. The dark "trails" after each call are the echo within the forest. Each calls lasts for about 0.5 sec and is repeated at about 2 sec intervals.
The call did not match any of the sounds I am familiar with. It was powerful, not a gentle call, as can be judged from the echo. The timbre made me think it was mammalian rather than avian, if it were the latter only a large owl would be likely.
However earlier in the morning I had seen fresh tracks in the snow about 1 km south of the recording site which I felt at the time may certainly have been a Lynx. The tracks were rounded like a cat, four toes and a pad clearly visible, longish stride (close to a metre ?), at least 3 times the size of nearby fox tracks. The tracks approached a bank where the animal had clearly sat back and leapt about 2m forwards and 1.5 m vertically before landing and walking into the forest. No human tracks nearby so I ruled out a dog-walker.
It was only after returning home and listening carefully to the recording and searching the for reference material that I linked together the tracks and the call and wondered if I had indeed been able to record a Lynx.
Subsequent to this story, with the assistance of Prof Urs Breitenmoser, a lynx expert of more than 30 years standing at the University of Bern, I have now been able to confirm that this is indeed the call of a Lynx.
[NOTE: Recordings were made with a Telinga Pro 5 microphone in a hand held parabola, recorded on a Fostex FR2LE digital recorder].