August at Nanjizal

Whilst September is the official start of autumn, migration has been in full swing at Nanjizal during August. During the month, there was no coverage from the 14th-20th (peak Sedge Warbler passage) due to family holidays and a short period at the start of the month. None the less, a non-too-shabby total of 1,698 new birds was achieved. Unlike a lot of coastal sites, good numbers of birds at Nanjizal usually coincide with still clear nights where the birds can pick good habitat, rather than being happy to land on the first bit of land they see whilst flying through inclement weather. As you can see from the totals the main species trapped are species that have a tendency to migrate SSW in autumn, with Sedge Warbler and Blackcap both funnelling down in big numbers. This funnel affect also brings a good number of dispersing British Robin, as we always get good numbers at the end of August into September. Other species such as Willow Warbler are never in such large numbers.

Top 10 species ringed in August

Sedge Warbler	837	Reed Warbler	80
Whitethroat	192	Grasshopper Warbler	56
Willow Warbler	176	Robin	56
Blackcap	107	Wren	25
Chiffchaff	102	Garden Warbler	14

Ringed birds recaught during the month came from Scotland, Leicestershire, Wales, Cheshire and Belgium, all bar one being Sedge Warblers. Most species seem to have done OK, with Whitethroat, Blue Tit, Great Tit and Grasshopper Warblers picking up after a slow start. Song Thrush seem to have done very well locally. Other unusual species ringed included seven Tree Pipit, two Firecrest and two Spotted Flycatcher.

The month also saw a few rare and scarce birds appear in the nets, predominantly birds from the south, as there hasn't been much arriving on the east coast to filter down. A blast of south-eastlies on the 22nd seemed to do the trick and a good run started with a Wryneck on the 24th, white-spotted Bluethroat on the 25th (one of 224 birds ringed that day). The 26th then produced the second Melodious Warbler of the month (the first was on the early date of 10th) and for the second month in a row a Blyth's Reed Warbler, this time a first-year bird.

Late autumn 2016 at Nanjizal - 100 Yellow-broweds and counting

Like many ringing sites in the UK, 2016 didn't seem to be the best of breeding seasons, with the cold, wet spring seeming to have reduced the amount of successful first broods. Compared to 2015, the most noticeable drop in numbers over the autumn was for Sedge Warbler, from over 1,300 ringed to barely 700 this year. This may have been due to the weather and slightly reduced coverage, but the national picture seemed to be show a poor breeding season. Blackcaps were late arriving in September and, like Sedge Warbler, in much lower numbers. The current total of just over 1,450 again compares poorly to the 1,933 ringed in 2015. The only real up sides saw Willow Warbler pretty stable at 469 compared to 473 last year, and Whitethroat actually increased, from 248 to 366.

During September coverage was similar to last year, but increased dramatically in October with extended periods of calm weather. During this later part of the autumn, the most noticeable absentees were the crests. There may yet be more to come, but the total of just 167 Goldcrest is well down on last year's 469. Similarly, just 27 Firecrest ringed so far doesn't compare to the bumper catch of 114 in 2015. The highlight of the autumn though was the mass arrival of Yellow-browed Warblers. After the dramatic increase in 2015 (with 22 ringed), this autumn has so far seen an incredible 105 birds ringed, with 13 ringed in one day alone! Long-distance movements of Yellow-broweds are rare, so we were surprised to catch a bird in 2015 ringed in Lincolnshire the week before. This year, we retrapped a bird on 31st October that had originally been ringed at St Abb's Head, Borders on 9th October, almost 700km to the north.

Other unusual species trapped during the autumn include two Nightingale, four Wryneck, Melodious Warbler, Marsh Warbler, an unprecedented two Paddyfield Warblers, two Dusky Warbler and Little Bunting. With the weather now turning for the worse, it's doubtful we'll get many more days in before packing up at the end of the month, which is a pity as the thrushes have arrived and the ongoing turnover of Chiffchaffs has included numerous tristis, with several 'Siberian' Lesser Whitethroats also turning up, but more on these later...

Early autumn at Nanjizal

August is always an interesting and busy time at Nanjizal, with the first big push of migrant warblers coming through. Where other Cornish sites are catching <100 birds in a session, the valley at Nanjizal regularly produces catches three times this number. Just over the last week, morning catches of 341 and 281 have been dominated by Sedge Warblers (201 on one morning alone), but in amongst them have been a few more interesting species.

Wednesday morning produced an early Melodious Warbler (above) and also Nightingale (below),
actually a much rarer species in the county!

Anyone still stuck for an autumn ringing trip away might want to consider a trip down to Cornwall, so check out some extra info here.