6 - 8 meters is quite close indeed. The grebes at Reesor pond would never allow me to get that close. When I approach the viewing mound I usually bend down to conceal myself behind the bushes because if any grebe were close they would dive,or race away as soon as I became visible. I even considered setting up a blind cloth stretched between two poles to make my approach, or anyone's approach less conspicuous. Most of the pond exists north of the observation mound so its utility would serve that side. Grebe seldom appeared south of the mound. I guess the water there is too shallow. I once stopped by the pond on my way back from an errand on a late morning after heavy rainfall. Light level was very low due to heavy overcast and lingering fog. I didn't expect to see anything. I approached the observation mound rather carelessly and looked north through the fog to see what I expected to see ... unoccupied water. I then peaked over a bush to check-out the narrow isthmus between the mound and the small island about 10 meters away to the east. There were two young PB grebe in the calm water only 5 meters away, maybe less. I sure wasn't ready for that discovery. I had a camera in the car and so I crept back to get it. By the time I returned they were a little farther away but still not acting alarmed. I only had a 135mm kit lens. The only other time I got close enough to even try taking a photo was in the late afternoon under dull lighting conditions. I was high up on the berm, not close to the water. I didn't have a DSLR then. I took a shot with a Canon G9 point-and-shoot. I was delighted even with that result.
