2 more Gull species (Black-headed and Herring) were noted elsewhere throughout the morning, the first for a while. It was a Great Black-backed Gull on Thursday that got me thinking, and prompted me to get my maps out, resulting in this post. An adult (the 3rd record of the year) drifted over Scotsland Brook, quite out of place, at around 16:35. It soon struck me - within about a half kilometre from here to the west, I had seen Kittiwake, Great Black-backed Gull and 2 Cattle Egrets, all flying north, in the last 3 weeks. There surely had to be some reason behind this remarkable run, and below is a possible theory I have come up with.
The Hascombe Gap
|Hascombe Gap map|
The gap just beyond this collective stop, between Loxhill and Hascombe, is where the aforementioned sightings have come from. It seems possible that any birds following the Arun from the coast (should they not deviate at Pulborough/Loxwood) will find themselves here, at the end of the thinning streams, and will perhaps drop down to reorientate. It takes some favourable decision making, and maybe is a little ambitious, but it's just about possible. On a larger level, the gap extends from Loxhill in the west to Smithbrook/Rowly in the east, where the Wey & Arun canal is found continuing north, so this whole area could turn up something. Given the gap is most likely to effect birds moving up, spring is likely the best season for wayward bits and pieces.
It would seem any bird that has ended up here, should it wish to carry on following water, would have little choice but to continue north, through and just past the top of the patch, where the Wey & Arun meets the Wey at Shalford. The Thorncombe valley provides a natural funnel for this short journey, and would go someway to explaining the occurrence of species like White-fronted & Brent Goose, (presumed) Bewick's Swan, Curlew, Black-tailed Godwit, Whimbrel and a plethora of Raptors and Passerines all heading north/south over the last few years.
On the contrary, birds turn up at any place, and at any time, and maybe it's all just freak fortune!
The Shalford Split
|Shalford Split map|
Long-tailed Skua, a host of Gulls (including Sabine's and a flock of c.60 Kittiwakes), and a myriad of Waders/Raptors/Herons etc have all been recorded at Unstead. I am likely to miss any birds that are successfully following either river, perhaps being a bit far south of the split, but anything reorientating could/has passed over.
This, also, could be pie in the sky. Some theories suggest flyways don't really exist. Perhaps this is all overthought. Personally, I think there could be some logic behind it, and I will certainly be keeping it all in mind during the coming weeks.