A Hectic Morning

Will and I met up at Rawcliffe Moss at 6am for another of our regular warbler sessions. It didn’t take too long to realise that the overnight patchy rain had not only interrupted some migration but left plenty of birds in the immediate location. We started catching even as we finalised the half erected nets, and then didn’t have much of a break until we packed up at 11am. In fact we were so busy there is something a shortage of images from the session and we may have missed some of the visible migration, although most of the movement seemed to be taking place in front of our eyes in the mist nets.

Features of the morning were yet more Whitethroats and Willow Warblers plus the continuation of the Chaffinch migration first noted on Thursday. In all we caught 52 birds, 51 new and a single recapture. New birds: 18 Whitethroat, 12 Willow Warbler, 5 Blackcap, 2 Reed Warbler, 9 Chaffinch, 1 Sedge Warbler, 1 Dunnock, 1 Great Tit and 1 Blackbird. The single recapture was a Dunnock from recent weeks.

Eighteen Whitethroats is a good score for such a tiny spot on a map, but this takes our tally of Whitethroats here to 132 for the year. Of the 18 today there was but a single immaculate adult with just completed moult. Note the strong eye colour.

Whitethroat adult

Today's far from unlucky 13 Willow Warblers took our year on the moss to 114 individuals.

Willow Warbler - juvenile

The Blackcap below is a juvenile male, the cap just abrading from the juvenile brown to the winter black.

Blackcap- juvenile male

The single Sedge Warbler caught displayed very prominent fault bars across its tail, an obvious juvenile feature.

Sedge Warbler - juvenile

With many ringing sessions there is an element of just ringed birds finding a net again soon after release, either almost immediately, within a few minutes, or up to an hour or two later. This morning it became noticeable how this simply didn’t happen when almost all of the newly ringed birds didn’t reappear, but very quickly continued their onward migration. We can often see this happen due to the site’s open geographical location that gives clear views to most compass points.

Our busy ringing meant less time devoted to birding but we noted c150 Swallows heading south, 1 Tree Pipit over, c40 Chaffinch heading south and several Greenfinch and Linnet. The Goldfinch roost here is still active with c120 birds leaving the roost at the relatively late time we arrived. The departing Goldfinches attracted in a marauding Sparrowhawk, with a second high flying Sparrowhawk seemingly headed south round about 9am.

Otherwise, 4 Buzzard, 1 Great-spotted Woodpecker, 2 Alba wagtails, 1 Grey Wagtail and 1 Tawny Owl tucked in close to the tree trunk today.

Tawny Owl

Final Swallows And Something For The Weekend

On Thursday evening at Hambleton I ringed the last young Swallows of the year, a nest of three where two eggs lay unhatched, the latter a not unusual outcome at the end of a busy but less than ideal season for Swallows. That’s 54 birds nestlings ringed at the site this year; just an average sort of year without it turning into the disaster I feared during the poor weather of May and June, but figures which broke no records. After this final brood, there are no more active nests at this site so there will be no Swallows finishing off the season into September this year, although there are still birds around other local farms.

This morning saw Swallows again when I looked around the Pilling patch from Lane Ends to Fluke Hall and counted about 140, scattered about the fields and along the shore. With such low numbers about and little sign of visible migration there seems to be a small likelihood of another large wave of Swallows following the mass emigration that took place in early August. Nowadays Swallows arrive historically early during late March and the first week of April, but are perhaps also departing the UK on a different timescale?

Swallow

The image above is from Pilling Water, where I also counted 10 House Martin and saw most of my other birds, best find of which was a Green Sandpiper, flushed from a puddle of water in the sheep pen on my approach. It headed over to the wildfowler’s pools, as regular a spot as any to find one, but there’s no point in trying to photograph an out-in-the-open Green Sandpiper, one of the wariest birds ever. Little point also with 20/25 Teal in the ditches, another species that always fly off long before a human gets too close. The chap dropping the daily wheat supply to the wildfowl told me there have been 200+ wild Teal lately, not to be confused with the farmed Mallards put out for sport.

About here and long the sea wall I found 4 Grey Heron, 1 Little Egret, 1 Redshank, 6 Linnet, 8 Goldfinch and 3 Wheatear. The Wheatears stuck to fence posts today, not to my ideal catching spot of the shore side rocks.

Wheatear

Out on the shore were 3 Ravens, a species now becoming more commonplace in the Fylde where they nest in quiet woods and up high on electricity pylons. I took a few shots of a Kestrel, hovering and circling with an entourage of Swallows.

Kestrel
Kestrel

I spent a quiet couple of hours, taking a rest from the hard labour of ringing sessions on the moss, but if the weather holds those pliers need a spot of oil for the weekend.

Well Sorted

Firstly my apologies to readers for the messy appearance of the blog for the last two days when the right hand column ended up below all the posts. This was caused by the simplest of problems, a stray piece of HTML overlooked in my last post Slightly Cuckoo. In the end the post title proved more accurate than envisaged. In due course and to compensate for this dreadful mistake, more new Cuckoo pictures will follow soon on Another Bird Blog.

I fixed the Blogger glitch this morning at 5am, just before I made tracks for Out Rawcliffe and a spot of ringing. On such a fine, wind free morning I suppose Will and I hoped for a big catch this morning, the first one for some time where we could use a full spread of nets. The overnight clear skies may have moved birds on ahead of us, our excuse for not catching enormous numbers. However we achieved a great variety of birds with yet more warblers plus witnessed clear signs of autumnal visible migration with our in-between net rounds birding.

We totalled 32 birds, 29 new, 2 recaptures and 1 “control”, an adult female Chaffinch ringed elsewhere – ring number R988282 other ringer bloggers out there? New birds: 9 Willow Warbler, 6 Chaffinch, 3 Blackcap, 3 Whitethroat, 2 Tree Pipit, 2 Lesser Whitethroat, 1 Garden Warbler, 1 Robin, 1 Treecreeper and 1 Blackbird.

Tree Pipit
Tree Pipit
Treecreeper
Lesser Whitethroat
Blackcap
Garden Warbler

Our recaptures: 1 Willow Warbler and 1 Whitethroat. As we are now well into the month of August the Whitethroats moving through the site are almost exclusively juveniles, i.e. 63 of 68 Whitethroat captures in the last 30 days have been young birds of the year. That is because most of the adults migrate earlier than the juveniles, young of the year which in August can be correctly aged but not sexed. Adult Whitethroats can be difficult to accurately sex at most times, in fact it is probably impossible in the field in August when they undergo moult. We thought today’s moulting adult may have been a male, until at home a check on IPMR records from May and June showed it to be a breeding female.

Likewise, autumn Willow Warblers are difficult to age and it is only in the hand that anyone can say with certainty that an individual is an adult or a juvenile.

Whitethroat moult
Whitethroat adult
Willow Warbler

More signs of autumn appeared this morning with visible Chaffinch movement – circa 30 birds passing overhead, contact calling as they headed south, then of course the capture of another ringer’s Chaffinch. Tree Pipits also fell into the “vis mig” category with 2 caught and a minimum of 4 birds overhead. The morning also saw a marked passage of Alba wagtails with upwards of 18 individuals heading west, the appearance of more Sylvia warblers and the early morning sound of Robin sub-song, a species that proved to be first in the nets.

Other birds this morning: 80+ Swallow, 4 Corn Bunting, 4 Grey Partridge, 1 Kestrel, 2 Buzzard and 50+Goldfinch. I almost forgot – the female Sparrowhawk that flapped from the net before we could reach it. Oh well there’s always another day.

On the non-birding front, Will who is a bit of a wildlife sleuth found the footprints of a Stoat where we often see one running alongside our plot, but we didn’t see the animal today, just Brown Hares and Roe Deer.

Stoat tracks

Slightly Cuckoo

Sue thinks I’m daft, slightly cuckoo even for spending so much time birding and ringing, even in the most off-putting weather. But occasionally the unpromising days turn out to be actually not bad, just like this afternoon when I took a trip out Nateby way after the morning rain had cleared even though the cloud remained and the stiff breeze still blew from the west.

After many years of carefully nurturing the farmer, I am ok to take my car down his track, a ploy that worked well when I found what I thought to be the Cuckoo of last week, some way off from the original spot. The Cuckoo didn’t take too much notice of the car halfway through the field gate, enabling me to get a few more pictures

Cuckoo
Cuckoo
Cuckoo

Cuckoo
After a few minutes I realised there was actually not one but two Cuckoos, having a bit of a Barney over possession of the good feeding they had found, but keeping a respectable distance from each other until their paths crossed. The few distant shots below are the best I could get of their squabbles where they appeared to employ their red juvenile gapes in threat posturing. It’s rare enough to see a single Cuckoo nowadays so I was doubly lucky to witness this behaviour.

Cuckoo
Cuckoo

After a while I left the Cuckoos, parked up the car out of tractor’s harm and took a walk where things got even better when a Swallow hunting Hobby came close by. Not unusually it was the Swallows that drew attention to the raptor with their twittering alarm calls; I watched as the Hobby continued towards Nateby village, disrupting more Swallows feeding around the next farm buildings before it was lost to view.

Hobby

Following those events it was hard to concentrate or better the day but I also saw 6 Whitethroats, 3 Buzzards, 1 Kestrel and 80+ Swallows, then 6 Swift heading south.

Buzzard
On my way home I promised Farmer Philip a picture of the Cuckoo if there was a reasonable one. Philip hadn’t seen or heard a Cuckoo on his land for several years.

Cuckoo
Cuckoo

Sunday Jobs

After Saturday’s disappointment Will and I promised ourselves another bash today so met up again, usual time, and usual place. As we hit the moss road at 0615 a heavy shower threatened to wipe out our ringing session: the downpour didn’t last and we soon erected just three nets in the eastern most part of our plot, mindful of the promised scattered showers and 15mph westerly for 10am.

It didn’t rain more but the stiff breeze did curtail the session early at 1030. Despite this we caught a good mix of yet more warblers and several finches, during what proved an interesting and varied morning of birding and ringing.

Our overall catch was 27 birds of 8 species, 22 new and 5 recaptures. New birds: 5 Whitethroat, 5 Willow Warbler, 6 Goldfinch, 2 Great Tit, 1 Chaffinch, 1 Blackcap and 1 Lesser Whitethroat – not only one of the smartest warblers, but the first of our year. Recaptures: 2 Whitethroat, 2 Willow Warbler and 1 Blackcap.

Lesser Whitethroat

The young Blackcap had almost dispensed with its brown cap and sported a not quite black hood.

Blackcap

Many of the young Goldfinches are now in stages of their post-juvenile moult, and with a little care it is possible to sex some of them, like the juvenile male below. Despite the lack of Goldfinch red on the face the new black nasal hairs show that this bird is a male - a female has greyer nasal hairs.

Goldfinch

Birding wise there was perhaps a little evidence of finch movements, with several Greenfinch and Chaffinch, but also 4 singles of Lesser Redpoll, all chattering south. Local Linnet and Goldfinch numbered 15 and 35 respectively. We estimated Swallows this morning at 80+, but found no difficulty in counting the single Swift that headed north about mid-morning. Otherwise, 1 Great-spotted Woodpecker, 60 Woodpigeon, 3 Buzzard, 1 Kestrel, 2 Pied Wagtail and 4 Skylark.

Sunday On The Moss

About 9am we had brief views of a cream-headed female Marsh Harrier before it flew off in the westerly direction of Pilling Moss, disturbing dozens of gulls and Lapwings from its path. Not the bird we saw here a week ago, and definitely a different bird.

On the way home I called at Hambleton to ring the penultimate brood of 4 Swallows for the year, where youngsters ringed last week now looked on the verge of leaving their stable. The final brood should be ready for ringing on Thursday next.

Swallow

I just looked outside at the lawn. With all the rain of the last week the grass really needs a cut. OK it’s Sunday afternoon when we should all take it easy, but if I go and get the job done now there are a few Brownie Points on offer for next week’s birding.

More Water, More Warblers

Will and I met up at Out Rawcliffe this morning hoping for another decent catch of warblers to boost the already good numbers for the year. Prior to today, and after a worrying and slow start to the summer catches, our Willow Warbler total here for the year stood at 82 and our Whitethroats at a convenient and precise 100 birds.

Even this morning the rain and cloud of the past three days still hung over the moss as patches of drizzle and rain headed inland towards Bowland where the low cloud obscured the topmost fells. Watching the clouds roll in we put up a less than ideal length of netting, a strategy which proved of mixed success when we later found it easy to close the few nets for a while to let the drizzle pass over, but which resulted in a slow, interrupted and frustrating morning.

Our catch was pretty poor with just 14 new birds and 5 recaptures. New: 6 Whitethroat, 5 Willow Warbler and 1 each of Reed Warbler, Goldfinch and Blackbird. Recaptures: One each of Goldfinch, Dunnock, Whitethroat, Willow Warbler, Chiffchaff and Blackbird. The Blackbird recapture was ringed here as a nestling on 27 July, so we know that at least one of the four nestlings ringed that day survived to fledging stage.

Reed Warbler
Whitethroat

After today here our 87 new Willow Warbler catches break down to 47 adults, 29 juveniles and 11 nestlings. Whitethroat totals now stand at 106 birds - 28 adults, 74 juveniles and 4 nestlings.

Willow Warbler
Whitethroat

The poor visibility also denied us much opportunity for birding but we clocked up 80 Swallows, 8 House Martin, a post summer flock of 70 Woodpigeons, 4 Corn Bunting, 8 Mistle Thrush, 30+ Goldfinch and 17 Linnets. Looking out for raptors realised 1 Kestrel, 1 Sparrowhawk, 2 Buzzard and the inevitable Little Owl, seeing us off its patch once again.

Little Owl

If it’s fine in the morning we’ll try again.

Did You Sleep Well?

There were three words in particular that stuck out from Eno’s North West weather forecast last night, Gloomy, Damp and Heavier. The first two words are self-evident with the third relating to the intensity of droplets falling from on high. Hence I find myself sat at the PC again, thinking and blogging about birding without actually picking up my bins or pliers. In fact after recent weeks of seeing huge Swallow roosts and finding for the first time a Goldfinch roost, I found myself reflecting upon birds and their sleeping arrangements, in particular their communal roosts.

Lots of species roost communally, mostly outside of the breeding season. We have all seen evening flights of gulls heading out to sandbanks, watched massed waders on the tideline or marvelled at the acrobatic formations of thousands of Starlings or Red-winged Blackbirds at dusk. Maybe we have watched a procession of Wrens making their way into a garden nest box to spend the night, or disturbed the Blackbirds from the thick Holly bush near the front door. As a birder and a bird ringer I have been interested in roosts for a many years and both watched and worked communal roosts of Swallow, Chaffinch, Brambling, Linnet, Tree Sparrow, Greenfinch, Goldfinch, Redwing, Blackbird, Fieldfare, Pied Wagtail, Yellow Wagtail, Long-eared Owl, and various mixed wader flocks.

Chaffinch

What all those gatherings have in common is that the birds are resting, roosting and sleeping, but it is not quite the slumber we humanoids know of eight hours tucked up in a warm bed. A bird’s disturbed and restless sleep that appears to us more like a quick nap is in fact a product of their innate ability to distribute sleep between the right and left hemispheres of their brain and effectively remain awake in the other; hence the roosting bird with one eye open, head tucked in, but always alert to predators. Also, birds that roost off the ground have specially evolved tendons in their legs so that when they are on a perch and relax their legs, their feet automatically curl around the perch and hold on with a tight grip so they can sleep without falling off. It’s easy to test that function out by allowing a Sparrowhawk or Kestrel to grip a finger or other suitable part of your anatomy.

Sparrowhawk

Studies into communal roosting in birds theorise three main benefits: Guy Beauchamp, The evolution of communal roosting in birds: Behavioural Ecology (1999).

1. A reduction in thermoregulation demands, (Thermoregulation is the ability of an animal to maintain body temperature within certain boundaries, even when the surrounding temperature is very different). The presence of nearby birds in communal roosts may reduce the energy demands for thermoregulation by for instance huddling together and thereby lessening the cooling effect of wind speed or direction. My experience of winter finch and thrush roosts has shown how they favour thick evergreen bushes in sheltered spots to spend the night, but conversely Fieldfares alone amongst the thrushes seem to favour rough grassland in which to pass the dark hours. The whole idea of warding off the chill by crowding together makes absolute sense when thinking about a tightly packed flock of waders on a windswept winter beach.

Sanderling
Fieldfare

2. A decrease in predation risk. For instance, the presence of more eyes in a communal roost may increase predator detection. In addition, the sheer number of individuals using a communal roost may decrease the risk of predation to an individual bird through the dilution effect. However, the greater conspicuousness of communal roosts may mitigate against the dilution effect, i.e. we have all witnessed how large roosts attract several predators. The geometric structure of the communal roost is also thought to provide increased predation avoidance; e.g. individuals that occupy central positions in a communal roost may be buffered from predators to a greater extent than birds sleeping on the edge or higher up. Does the Sparrowhawk dive into the Swallow roost and carefully select a bird from the centre or take the first one it happens upon near the top stems or the outer margins of the reed bed?

Swallow

3. Increased foraging efficiency. Increased foraging efficiency is often considered the main advantage of communal roosting in birds, whereby a roost acts as an information centre where unsuccessful foragers can follow more successful or experienced companions to good feeding areas. Communal roosts have been hypothesized to be an accumulation of foragers spending the night as close as possible to good feeding areas, i.e. birds join large roosts to reduce commuting costs from the daily centre of activity or simply join in as they pass on migration. Observations from local roosts of Swallows and finches support this theory with the whole roosting process from start to finish taking a couple of hours as birds arrive in small groups from all compass directions before settling down for the night. Ringing recoveries from the same periods also support this theory with quite local recoveries but also birds from further afield or indeed highly migrant birds like Bramblings recruited into a large Chaffinch roost, or on other occasions Sand Martins and Yellow Wagtails joining a Swallow roost.

Brambling

Well it’s now 2pm but still peeing down and whilst the above makes food for thought, creates a post for Another Bird Blog and passes an hour or two, I’m now tired and going for a quick snooze.

Lesser Black-backed Gull