It appears that you had a good day. Excellent finds and successful proximity tactics, whatever they may have been. Were you hidden and laying in wait, or were you dutifully camouflaged in a lenticular motif, or were you just plain irresistible to these birds in some inexplicable fashion? I can't see that a PB grebe would allow you to position yourself so intimately without being spooked. It's not a decoy, is it? I would like to try the small marsh at the foot of Liverpool Road but there is no place to park ... all pay-parking now because I've seen a Marsh wren at that location a couple of times in the past ( few years ago) but beyond the reach of my 200mm lens at the time. Parking was free then, as long as it was during the week. Thanks for posting these delightful results that I'm guessing were taken at CSSP.