Today's parity in numbers of 'phyloscs' and reflection on comments about proportions observed on an east Devon headland prompted a look at the data for here. Monthly maxima are regularly published in county Bird Reports to express species summaries, and less so 'bird-days' but there is another metric of equal value that isn't used, partly due to data insufficiencies, and that is 'average birds per day seen'. Each method have their pros and cons. During the 2010s, for instance, if guided only by monthly maxima this infers that Willow Warbler outnumbers Chiffchaff during the month of August in four of those ten years. However, since Willow Warbler occurs here more prominently as 'falls', this may hide the truth. The 'average birds per day seen' results reflect a more accurate representation of passage due to being a summary of all days in a month when the species was recorded, not just the one maximum count. Roughly overall, in Augusts of the 2010s, there were two Chiffchaff for every Willow Warbler (a 2:1 ratio).
Data capture, analysis and representation - Ivan Lakin |
On the Main Pond, 18 Mallard, the pair of Mute Swan and their two cygnets, a few Moorhen, a few Reed Warbler, and an immature Little Grebe. Just the raft of nine Common Scoter and single figures of Gannet and Kittiwake offshore early morning.
The late morning high tide was well observed and selected counts were 400+ Oysercatcher, 385 Curlew, 192 Dunlin, 113 Redshank, 81 Sanderling with yesterday's Spanish-ringed bird still; 43 Ringed Plover, 38 Whimbrel, a dozen Cormorant, ten Little Egret, nine Mediterranean Gull (2 juv, 1 fs, 1 ss, 5 adult), five Greenshank, four Common Sandpiper, two Turnstone, one Bar-tailed Godwit, a Common Gull and a Lesser Black-backed Gull.
A white-rumped wader on the beach that was larger than the Sanderling it was with flew off into the sun before it allowed identification, possibly Curlew Sandpiper.
The terns again entertained with 123 Sandwich Tern present that included the South African-ringed bird and a Dutch-ringed bird, both also seen here over the past two days. Also 11 Common Tern, including the individual without a black tip, and an adult Little Tern.
Little Tern with Sandwich Terns - Dave Jewell (left) and Lee Collins (right)
Wildlife news: a Jersey Tiger was in the Sycamore patch; two Clouded Yellow again in Greenland Lake, also single Golden-ringed Dragonfly and a Migrant Hawker.
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