I first heard its call then I went looking for it and saw it in the reeds near one of the ponds. When I returned to the same area a little while later it was in a shrub, which was tightly grown, beside the pond such that I could hear the bird but I had no hope of seeing it. The warbler eventually returned again to the little clump of reeds I had seen it in. I heard at least one other warbler calling, possibly responding to this one as they seemed to take it in turns to sing.