Today (May 14) around noon, Jess Findlay and I (RC) flushed a small, sandy-coloured wren along a weedy hillside at the "Esplanade Trails" behind the Penticton Yacht Club. Right away we were given the impression of a Marsh/Sedge Wren and upon pursuing it up the hill and around a few bushes we had a few very brief views and heard it call several times. At one point a Song Sparrow chases it through the weeds right toward me and it landed near my feet, but slightly obscured, then darted beneath a log.
I called my Dad who was up on the West Bench, and when he arrived we renewed the search and saw the bird fly from bush to bush twice then heard it call several times more--this time, the more diagnostic chip call: (http://www.xeno-canto.org/70080). It flew down off the grassy hill and down into the thick tangle that lines a wet ditch that parallels the beach and tennis courts. Both my Dad and Jess each had a brief look at it while I searched from above.
All in all we followed it around for about 1 hour before losing it in the tangle. It will almost surely spend the rest of the day there but finding it is a huge challenge as it rarely calls and is extremely secretive.
I will try again tomorrow morning and will post my findings.
No photos/recordings were obtained. House Wren was eliminated from consideration based on colouration, shape, voice, and behavior. Marsh Wren was eliminated partly by plumage, but more so by voice, with additional consideration given to habitat (no marsh for miles and the weather is fantastic so why would it touch down on a weedy hillside?).
This is the 4th record for BC and 1st for the Okanagan.
If you want to try for it, drive to the Penticton Yacht Club/tennis courts at the SE corner of Okanagan Lake in Penticton. Enter the forest at the main trail-head then take a left and follow the main trail that leads to the beach. The bird was observed both in the weedy and bushy hillside on the right side of the path, and down in the thicket that lines the tennis courts on the left side of the path.
May 16 UPDATE: The bird apparently called in response to a recording this morning! (Eva Durance)