There can be little doubt that for the rarity-seeker September and October offer the greatest opportunities for chancing upon their quarry. There is always the chance of a wayward stray regardless of the weather, or location. However, these months also offer the greatest likelihood of an east coast fall when several factors simultaneously come together to produce a memorable outcome.
An east coast fall is on most birders' wish list each year. They are spectacular and exciting events, but rare and unpredictable in occurrence. The sight of coastal bushes and fields draped in large numbers of common migrants, with the knowledge that the next bird you look at could be a rarity, explains why many of us have an unhealthy obsession with weather forecasts!
The most famous fall occurred on 3rd September 1965 when tens of thousands of migrants were deposited along the coasts of Suffolk and Norfolk. One observer walking a 3km stretch of coast to the south of Walberswick (Suffolk) on the 4th estimated that there were 15,000 Common Redstarts, 8,000 Northern Wheatears, 3,000 Garden Warblers, 1,500 Whinchats, 1,500 Tree Pipits and 1,000 Willow Warblers, plus unprecedented numbers of rarer migrants. The actual numbers of birds involved must have been astronomical and presumably far exceed any estimates of the event.
Predicting falls is never easy. Ideal conditions would appear to be a nice high pressure system over Scandinavia to prompt migrants to move, a low pressure system with bands of rain located across the low countries and east coast, coupled with drifting winds with an easterly element with which to carry the disoriented migrants across the North Sea. Falls of varying size and quality can occur under a range of conditions, but the conditions described above rarely fail to deliver.
Over the weekend of the 7th and 8th September it was becoming clear to rarity-finders that a window of opportunity for such an event was shaping to present itself early in the week. A high pressure system was establishing itself over Scandinavia, temperatures were set to drop and clear skies would presumably result in the large-scale movement of passerines heading south. However, what the migrants could not see was that a low pressure system was also becoming established across the low countries, bringing southeasterly winds and heavy rain moving northwards along the entire east coast. Such an obstacle suggested that a fall was likely and that it might occur overnight on the 9th. With the prediction of brightening skies over the east coast on the 10th, that would be THE day to find rarities under dry and more settled conditions. The early date implied that actual rarities would be few and far between, with a relatively small range of potential species, but it was peak time for Greenish Warblers and scarcities such as Red-backed Shrikes, Wrynecks and Barred Warblers.
No doubt the early stages of many an 'illness' amongst birders began to be feigned on the 9th in an attempt to secure a 'sick-day' for the 10th! The predictions appeared to be going well, with few migrants evident by midday on the 9th. However, during late afternoon as the rain moved northwards it became clear that a significant fall of common migrants was taking place, with large numbers of birds arriving in north Norfolk and as the day progressed activity moved to the coastal stretch between East Yorkshire and Cleveland. By darkness it was evident that a large fall had taken place between Norfolk and Aberdeenshire, with the brunt of the activity in north Norfolk, Yorkshire and Cleveland. As expected large numbers of migrants were still present on the 10th as many took the opportunity to feed up in warm and sunny conditions. Clear skies overnight on the 10th/11th ensured that many of the commoner species moved-on, leaving the rarer species, which had presumably travelled that bit further. Throughout the rest of the week drifting easterlies ensured a steady arrival of scarcities, but by the weekend activity had once again become focused on the sea as northerlies effectively cut off the rarity vector through the North Sea.
Nevertheless the fall was a fantastic sight for anyone who managed to get out and about. The bulk of the fall was accounted for by Pied Flycatchers, Garden Warblers and Common Redstarts, with Whinchats and Wheatears also evident. For example, on the 10th, Spurn (East Yorkshire) logged 112 Pied Flycatchers, 175 Common Redstarts and 42 Tree Pipits. In keeping with the autumn so far, Common Crossbills also featured strongly in the fall, with at least 600 birds reported, the majority in North Yorkshire and Cleveland, where 195 were at Hartlepool and 100 at South Gare. Sadly for many observers the only Two-barred Crossbill of the period was a male on Fair Isle.
As expected rarities were few and far between, with most, as usual, being located after the main arrival of birds. At least a dozen Greenish Warblers occurred during the period with nearly all between East Yorkshire and Fife and an excellent collection of birds in Cleveland, though just one Arctic Warbler was found, occurring several days after the main fall. Four Great Snipe were reported, one at Blakeney Point (Norfolk) proving popular. On the Northern Isles, a male Two-barred Crossbill was on Fair Isle, three Yellow-breasted Buntings were present as was a Black-headed Bunting and an Isabelline Shrike was on Fetlar, though these were probably not directly associated with the main fall which appeared to have lost its impetus by the time it reached these magical islands. Elsewhere, 2 Red-throated Pipits were reported, Thrush Nightingale in Norfolk, a Paddyfield Warbler was on North Ronaldsay and three Booted Warblers were seen, plus a Rustic Bunting was at Cley.
Of scarce migrants, at least seven Richard's Pipits were early, as were a similar number of Yellow-browed Warblers. Bluethroats are an extremely rare autumn migrant nowadays and just six were reported, with a similar number of Grey-headed Wagtails, four of which were at Spurn. A Golden Oriole in East Yorkshire and a Short-toed Lark in Norfolk added to the variety. As always, Wrynecks were a prominent feature of the fall, with at least 85 seen, including six at Spurn and four at Filey. Around 50 Red-backed Shrikes were reported, including five at South Gare, and just over 50 Barred Warblers were widely spread along the coast. Always pleasing to see, at least 35 Red-breasted Flycatchers delighted their observers, with at least four at Spurn on one date. Fewer Icterine Warblers were reported than might have been expected with 30 located, whilst at least 25 Ortolan Buntings and a dozen Common Rosefinches featured, though relatively few were on the east coast.
Distribution of records, 9th-15th September 2002 |
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 Wryneck |
 Red-backed Shrike |
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 Red-breasted Flycatcher |
 Barred Warbler |
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The actual numbers involved will have been substantial, and as is always the case under such circumstances it was not about how much was seen, but how much was missed?
