Preceding the upcoming national count of roosting Ring-necked Parakeets Psittacula krameri, yesterday’s afternoon Ruud Vlek and I visited the known parakeet roost in Amsterdam North. After crossing ‘The IJ’ by ferry and before meeting up with Ruud, I inspected ‘Overhoeks’ (former Shell headquarter) for the presence of Peregrine Falcons Falco peregrinus. At about 15:30 a single Peregrine appeared, circling above the tower. A few minutes later it perched on the tower’s concrete overhang. The bird was obviously in a hunting modus and flew off towards the west, away from my location. At 15:45, on a second walk around the tower, prey feathers were flying off the roof, indicating a prey had been caught.
Carrion Crow Corvus
corone, below the tower.
After meeting up with Ruud at dusk and our arrival at the roost, there were few parakeets present. But large numbers came in only shortly after, forming pre-roost gatherings in surrounding trees. At that time we counted 722 Ring-necked Parakeets.
Based on our past experiences at the roost site, we know that the gathering of the parakeets not only attracts our interest, but also that of several raptor species. At 16:52, just when the first few hundred birds had settled in the roost trees (where we were hoping to eventually conduct a total count) a Goshawk Accipiter gentilis appeared, diving straight into this group of birds. What followed was an explosion of parakeets, which all evacuated the roost site. We found back some of these birds in scattered groups in other trees in the area. These groups were then only photographed, but while doing this a number of birds returned from their hideouts and joined the groups that had already been inspected by us. At that point it became too dark for a recount.
Today I analyzed this last round of photos and these show the presence of at least 532 parakeets. Marking every visible parakeet in Paint and counting the dots is one of the preferred methods, but it can only be done when the photos allow it. Due to distance and parakeet density, on the second photo it got too difficult to distinguish all individual birds, so I probably missed a few there. Our first count (722 Ring-necked Parakeets) will be the result of yesterday’s action. I hope things will go easier on Sunday, the day of the national count.
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