Fledglings and Caterpillars

Some “fledglings” are just too big for the word.

Okay, it’s recently out of its nest and yes it’s doing the wing-flappy thing and calling for its parents to feed it, but it’s just too big and dangerous-looking. For me a fledgling is a small vulnerable thing. Not a harbinger of doom with great big talons.

So I’m going to call it a young Raven.

For the time being anyway. Without hearing their call, I find it tricky differentiating with certainty between Crows and Ravens – particularly when they’re at a distance, which they usually are. There were no distinctive “honk-honk” calls from the adult birds I saw up on the plain a couple of days ago.

I managed to get one or two pictures of the them in flight and although they had longish wings – a Raven characteristic – the tail was not particularly wedge-shaped, which is also a main identifier for Ravens. 

I tried to get an idea of the length of the young bird by using the 4 inch fence posts as a scale/guide. By my calculations (treat with caution) the young bird was a bit more than 21 inches long. So if the upper limit for crows is twenty inches, and the lower limit for Ravens is 21½ inches (RSPB guide), that does suggest the young bird was a Raven.

And when you compare the adult bird on the right of the above picture with the young hungry one on the left, the adult is a bit bigger still – more like twenty two inches (using the same method). But then I think the adult was a little closer in this photo so maybe that distorted things. I’m almost a hundred percent but not quite.

Ravens have been spreading across the country from the West in recent years. I know of one or two other nests not far away (their distinctive “honk-honk” was heard) which have produced young so it looks like another good year for the species. Not all birds have done so well. I learned the other day that a lot of Great Tit and Blue Tit nests have failed this year due to a lack of caterpillars following the record-breaking cold May.

Apparently those parents that did raise young successfully often did so with the help of suet pellets from garden feeding stations. Which ties in with what I saw a few times with the fledgling Blue Tits that I photographed a couple of weeks back.

The bright pink blob turned out to be one of the suet pellets that Chantal had put out on the bird feeder. Apparently they’re made with berry juice which gives them the strong pink tinge.

The nesting season continues. With more insect life about now, current nesters will probably have a better chance of success. I’ve noticed a bullfinch standing guard in an Elder bush on the other side of the field.

He occasional drops down and goes into the brambles where I suspect the female is on their nest. I saw the male goldfinch of the pair nesting in the ivy tree doing a similar standing sentry thing for a while a month or so back. I wonder if it’s a finch thing. They seem so vulnerable to me out on display like that – no shortage of Sparrow Hawks here – but then our Goldfinches survived and raised a brood so it can’t be that bad a tactic.

An upside down Goldfinch Fledgeling feeding on aphids on the willow tree.

I’ve now also spotted a female Whitethroat, and a delicate wee thing she is. I’m guessing she’s partnered up with the male that’s been around for a while now.  She’s even more secretive and cautious than him.

Rare appearance of the shy female Whitethroat, keeping her distance

The male did come close enough the other day for me to get a couple of better photos, but he was still flitting about in amongst the undergrowth, making auto-focusing difficult. Photographically challenging, but beautiful little birds.

Other species seen during the Raven walk included a Yellowhammer and a Stonechat, both singing their hearts out. I’m guessing they were proclaiming their territory or maybe trying to attract females. Whatever, they should have a better chance of success now.

Yellowhammer in full flow
Stonechat contributing to the background twitter of all the other downland birds.

So the unusually cold weather in spring this year had a devastating effect on caterpillars and the bird life that depended on them. But not all caterpillars have had a tough time of it. A couple of weeks ago I noticed an infestation of caterpillars on an Aaron’s Rod plant which had appeared in the gravel by our back door.

I initially thought they might be caterpillars of the Large White Butterfly – they had a similar yellowy green colouring – but it seemed strange that they were on an Aaron’s Rod plant, their normal food plants being of the cabbage family. But as the caterpillars grew bigger and I looked closer it became apparent they were something different. A little research revealed them to be caterpillars of the The Mullein Moth (the Aarons Rod is also know as Great Mullein). Their black and yellow colouring suggests they might be toxic which, I’m guessing, is why no hungry birds picked them off.

Apparently once the Mullein caterpillars have had their fill, they wander off and find a suitable spot to bury themselves and pupate, only reappearing as moths two or three – sometimes as much as five – years later.

After the driest and sunniest spring on record in 2020, and the coldest May on record this year, who knows what kind of a spring will await them.

Fledglings in Dappled Light

Back on April 17th, I took a series of pictures of a pair of courting Blue Tits.

(If you visit the website, rather than viewing on email or the WordPress Reader, you’ll be able to see the below slideshows rather than all the individual pictures.)

The males do a lot of schmoozing, showering the females with gifts – a juicy caterpillar here, a sunflower heart there – and I’d always assumed it was the Blue Tit equivalent of boxes of chocolates and bunches of flowers. But having watched the way the adults feed their fledglings over the past few years, I’ve started wondering whether the female’s approach is a bit more pragmatic than that.

The adult females puff themselves up and flutter their wings in a way that looks very similar to the behaviour of fledglings begging to be fed in the hours and days after they’ve left the nest. 

Could the females be imitating the chicks to see if their behaviour triggers a sufficient feeding response in the prospective male? Maybe they’re checking out the male’s parenting potential before they take the plunge. Doesn’t seem unreasonable: you’d want a male who was good at feeding duties, especially when you could have as  many as ten chicks to look after.

Last Thursday, May 27th, two days short of six weeks since the Blue Tit courtship display, the pair’s progeny fledged. I first realised it was happening when I came outside the backdoor and saw one of the adults perched on the electric cable leading to the house.

He had a juicy looking caterpillar and was twittering in a way that sounded like he was trying to tempt the chicks out of the nest box. I went to see what was happening and I could hear three or four of the fledglings already in the willow tree and there was one in the long grass of the field on the other side of the stream that was calling out repeatedly.

The willow tree, handily positioned for fledglings on their maiden flights

I didn’t see any others leaving the nest box so I’m guessing the rest of the brood – if there were any more – had already dispersed.

Most of the brood were up in the willow tree already.

It can be a bit tricky getting the autofocus to work when your target is in the middle of a tree with branches behind and in front

One fledgling higher up was preening himself thoroughly which was understandable after two or three weeks cooped up in the nest box with all the attendant creepy crawlies.

And then I noticed the fledgling in the long grass fluttering its way up to the lower branches of the willow. It just made it and clung on.

He struggled his way up the dangling branch to a more horizontal perch.

But he was partially hidden behind a vertical branch so I moved a little closer to get a better angle.

The fledgling didn’t seem too impressed by my presence.

A few squeaks and wing flaps later, and one of the parents was down to feed him.

As he perched there, the dappled light shifted as the wind moved the leaves in the branches above, occasional giving the effect of a spotlight trained on him. 

Handsome young fellow
Another one partially in the spot light

Photography gets a lot easier when the subject is on the same level as you and not far away. It’s also handy if the subject is unsure about flying away, unwilling to risk another flight quite yet. It helps too when there aren’t too many branches in front or behind. And when there’s a small puff of wind and dappled sunlight flashes through the leaves for a moment and illuminates your subject perfectly, it’s the icing on the photographic cake.

Of course the fact that the fledglings are clumsy and reluctant flyers does make them easy targets for predators. A few jackdaws landed in the willow tree and looked around for the source of the tweeting. I couldn’t help myself: I shooed them away. And one of the crows saw other jackdaws off as well, as if to say these are my juicy little morsels, not anyone else’s. And then a squirrel turned up. He’d tight rope walked his way along the electric cable that passes through the tree. I know they raid nests and they might just be tempted to go after a clumsy fledgling or two. It was like the bush telegraph had put the word out: easy meals in the willow tree today. Of course we shouldn’t interfere with nature, but then again…

…I shooed him off as well. They’ll have enough time to do their predatory stuff when we’re not around.

Strange Flutter

On the rare occasions over the past couple of weeks that I’ve been out into the garden – we’ve had pretty relentless cold winds and rain – I haven’t seen a huge amount of nest site activity. I suspect they’re either sitting on their nests keeping eggs warm, or the chicks have fledged and the families moved on.

There is one site though, where there have been plenty of comings and goings: the Long Tailed Tits’ nest in the brambles. And it’s a slightly weird kind of activity that I’ve not seen before.

Both parents seem to be visiting the nest regularly with beaks full of mushed up insect life – they clearly have a hungry brood – but they don’t go straight into the nest. They usually land nearby and then fly a few feet into the air above, and do a sort of fluttering hover for a few seconds, before dropping down into the tangle of brambles and the nest below. But they don’t always go down into the nest first time. Sometimes they land on the brambles and fly up and do the hover-flutter thing again, occasionally several times before finally dropping down to the nest.

(If you visit the website, rather than viewing on email or the WordPress Reader, you’ll be able to see the below slideshows rather than the individual pictures.)

It’s a strange and delicate display, almost a dance. And it’s conspicuous too. I’ve been wondering what the purpose of it is.

Log Tailed Tit Ballet

Pretty much all the other species of birds do everything they can not to be noticed entering their nest, or otherwise do it very quickly. Which is understandable with all the potential nest raiders around.

But not the Long Tailed Tit.

If they wanted to alert a partner of their arrival, a partner perhaps sitting on the chicks to keep them warm in cold weather, why not just make a gentle tweet, or call out in some way like other species do, while staying safely hidden and not giving away the location of the nest to any watching eyes. 

I can understand why they would need to enter the nest from above: The Long Tailed Tit nest has a roof to it, and the entrance is on the side near the top, so from above would be the easiest way to access it in a bramble thicket with sharp, potentially wing-shredding thorns on every side. And I can also understand why they might want to alert their partner to get out of the nest to allow easy access for feeding the chicks. But why be so conspicuous?

I wondered whether fluttering above the nest was some kind of evolutionary trade off: the security of a thorny bramble protection weighed against a necessarily conspicuous entering-the-nest-from-above behaviour. Maybe. But it seems odd that no other birds seem to do it.

Apparently Long Tailed Tits have a nesting success rate of less than twenty per cent and I’m tempted to think their conspicuous behaviour may be part of the reason. But then again their population is currently stable or increasing so they must doing something right.

And then I saw two of them fluttering above the nest at the same time. What was that about? If both the long tailed tits were off the nest either one could have entered straight away. Why still hover?

Second hovering long tailed tit, low to the right

A little while later, I noticed three Long Tailed Tits together, foraging in the large willow tree near by, and it occurred to me that the third adult might be a related bird perhaps from a failed nest that was there to help the original couple (Long Tailed tits are apparently well known for this behaviour). So maybe there were now three Long Tailed Tits – or more – raising the brood. After the very blowy, potentially nest-wrecking weather we’ve had lately (gusting to 45 mph today and all tomorrow), a few casualties would have been inevitable. So perhaps when there are two birds hovering over the nest at the same time, they’re waiting for a third to make way.

Thinking about it some more, I can’t remember ever seeing magpies or Jays trying to get at a nest in a bramble thicket, so maybe the Long Tailed Tits’ behaviour isn’t that reckless. Even if they know where the nest is, the corvids may not want to risk damage on the thorns trying to get at it. I’ve seen sparrow hawks going after birds from blue tits to pigeons, but their prey is usually taken when perched on a branch or in mid air by the pursuing raptor. I’m wondering if, when Long Tailed Tits are hovering up and down they would be difficult, unpredictable targets. And I suppose if a Sparrow Hawk mistimed its strike, it could easily end up tangled in the thorns, which would be a bit off-putting as well.

Whatever, their hovering dance behaviour seems to work, though a Whitethroat who was watching from another bramble patch near by looked sceptical.

I first noticed him about a week ago. He seems to keep his head down most of the time. I haven’t seen a female yet, but I have noticed him returning now and again to another bramble patch not far away, so he may be another bramble-patch-nester. Or it may just be coincidence. We’ll have a better chance of knowing when the chicks – if he has any – start demanding food. It’ll be interesting to see, if he does have chicks, what the Whitethroats’ nest-approaching behaviour is. I can’t see it being as much of a delicate dance as the Long Tailed Tits.

Mixed Feelings

We now know the location of the Goldfinch nest. They’ve chosen an old ivy-clad, and previously pollarded, willow tree that died two or three years ago from Honey Fungus. At the time we cut off all the dead willow branches to use for kindling, and the ivy has since pretty much taken it over. We now call it the ivy tree. The Goldfinches are nesting near the top, on the field side.

The “Ivy Tree” is to the far left.

I’ve seen one of them, I assume the male, spending a lot of time hanging around outside at various vantage points. A securing cable for the near-by pole for the electricity line is a favourite, if uncomfortable-looking, spot.

He’s been singing his heart out which is his way, I think, of proclaiming his territory. I’ve seen him chase off other Goldfinches that have been passing by or pottering about in near-by trees. And then his partner occasionally pops out from the nest and they go off to do a bit of together foraging.

Yesterday one of them arrived back at the nest with what looked like a piece of grass or two, so maybe they’re still applying the finishing touches. Finished or not, the female is spending most of her time on the nest at the moment.

The thick coat of ivy seems to make the old willow tree a popular location. Pigeons have nested there in the past and a pair of Robins are currently nesting further down, about three foot off the ground. There was a pair of them nesting there last summer and the young fledged successfully – we watched them leave the nest one by one on a sunny afternoon – so it may well be the same couple back again.

In the winter I looked over the area where I thought the Robins’ nest was, but couldn’t see anything. The old tree trunk is hollow and there’s a long narrow opening which the ivy has now largely overgrown.

The entrance to the hollow inside extends maybe a couple of feet above from where it’s visible.

I suspect the Robins might be entering through the ivy and that the nest is actually inside the tree. Then again, the ivy growth is pretty thick and the nest might just be nestled against the trunk with the leaves covering it.

One of the residents. They don’t like going in when anyone’s watching.

There’s more than one pair of Robins in the garden and field, and they’ve had a few tussles lately. We’ve also noticed them having a go at a pair Dunnocks, who I think may be the pair now nesting in the largish bramble patch (to the right in the picture at the top) along with the Thrushes and Long Tailed Tits.

Robin with Attitude – is there any other kind

It’s all pretty competitive out there. And dangerous. The old willow tree with the Goldfinches and Robins is next to a couple of conifers in which I suspect there are one or two other nests as there’s been a lot of small bird activity there recently. Every time a member of the crow family flies by a flurry of small birds raise the alarm and chases after them.  They went berserk a few days ago when two jays passed through at the same time. 

A potential nest-raider watching over the garden, looking out for any give-away signs

A lot of birds become more predatory at this time of year it seems. We have a pair of Greater Spotted Woodpeckers regularly visiting the garden. They’ve always been welcome visitors in the past, but they’ve taken Great Tit chicks and Blue Tit chicks from our nest boxes in recent years – once wiping out an entire brood, so my feelings about them have become a little mixed. 

I’ve also had a soft spot for our resident pair of Carrion Crows. I saw one of them, a year or two ago, messing about in the stream and watched as it selected a white stone from the gravel bed and then flew off to his partner in the field who he presented it to. Which was kinda cute and endearing. Then a few days ago I stepped out of the back door and heard a loud commotion by the stream – wild screaching and flapping. I saw a Crow with what I thought initially might be a duckling in its beak – we’ve had mallard broods here in the past – but a male Blackbird’s loud alarm call, and its sudden appearance chasing after the Crow, which was flying away across the field almost immediately, suggested otherwise. Seeing the fluttering, screaming bird in the crows beak was pretty shocking. I thought it was a bit early for fledglings – I haven’t seen any about – but on the other hand I wasn’t aware that Crows took mature adults.

It all happened very quickly and I only managed to get a hurried picture of the Crow with its prey when it reached the other side of the field. The yellow edges of it’s gaping beak as it was being carried away, and its mottled chest, suggest the victim may well have been a fledgeling rather than an adult, but I don’t think there’s enough detail to be sure. Whatever, it’s now also a case of mixed feeling when it comes to crows. 

Another spring casualty

There’s a lot of new life about at the moment, but quite a bit of sudden death too. I guess that’s the nature of Nature. It’s tough out there.

It’s All About the Brambles

The birds are doing their usual springtime partnering-up thing and I’ve noticed one or two species returning to nest sites that they used last year. Once again the brambles are proving popular.

A pair of Long Tailed Tits are back, which is a bit of a surprise as I thought they’d deserted their nest, situated in one of the larger bramble patches in the field opposite, last year. I’ve read somewhere that if nest sites are predated, the birds will not return, which doesn’t seem unreasonable. But than again maybe this is a different pair and the site just has potential-long-tailed-tit-nest-site written all over it. Who knows.

Anyway, the pair of them are now busy collecting building material for the nest which seems to include little bits of dried grass…

…lots of cobwebs – presumably to help bind other materials together…

Plenty of cobwebs under the eaves and in the corners of windows

…and what looks like pieces of lichen from a near by willow tree:

I thought lichen seemed an unlikely building material but I’ve learned from a website called Nurturing Nature that Long tailed tits do indeed use lichen for the exterior of their nests. In the pictures on that site it looks like a kind of green/grey pebble dash which camouflages the nest and, I’m guessing, might strengthen the structure too.

I’ve also noticed that the Long Tailed Tits seem pretty relaxed about hanging around above the nest site – in between, that is, their frantic sessions of nest material collecting. Their occasional laid back attitude is very different from the nervousness of a pair of thrushes which are back nesting in the same bramble patch but on the other side. They’re incredibly secretive. I’ve never seen them hanging out close to the nest site and they always seem to approach it in a very round about way, taking their time about it too. They seem to do everything they can to avoid attracting attention.

Spot the Song Thrush, watching me watching her. She subsequently flew off without going into the nest. It really does feel like they know when they’re being watched.

I first noticed them this year when on one of the pair nipped out from the bramble patch and swiftly flew away. The pair that were nesting there last year always flew off at high speed when exiting the nest. My assumption was that they felt exposed out in the open with all the potential predators about. We didn’t see any thrush fledglings last year and I wondered whether they might have been predated too. But they could have just moved away to somewhere with better cover as soon as they’d left the nest. It’s quite open in the field and Sparrow Hawks are regular visitors. Particularly when there are fledglings about and they have their own young to feed.

I saw one of the thrushes again yesterday, going into the brambles with a mouthful of goo-like material in its beak. Seems a bit early to be feeding young but maybe it was a beak-full of mud, which I know they line their nest with. There’s a ready supply by the stream. Talking of lining nests, I read on the Nurturing Nature website that Long Tailed tits use something like 1500 feathers to line their nests. That’s a lot of little feathers to find. Apparently the tiny young need serious insulation to protect them from frosty spring nights. I think they’re now approaching the finishing stages of nest construction as they’ve just started collecting feathers. Just another 1,498 feathers to go.

Other possible bramble-nesters I’ve seen include a Dunnock that I noticed sitting proprietorially on another bramble patch that I’m pretty sure a pair of them nested in – or at the base of – last year.

And I’ve seen a Gold Finch hanging around on its own which is unusual – they usually come in pairs or flocks – and I’m wondering whether he has a mate brooding a clutch of eggs near by.

I also saw a robin singing its heart out perched on some painfully sharp-looking brambles a while ago, but that may just have been a good vantage point for his performance. 

With all the different nest-raiding corvids about – magpies, jays, jackdaws, a resident pair of crows and even the odd raven passing through  – the thorny barrier of a thick bramble patch must seem like good nest protection for smaller birds that can nip in and out to their nests without a problem.

Yesterday, in one of my regular wanders up the garden I saw – and heard – a male Blackbird chasing away one of a pair of Jays. And there was a magpie lurking around as well. They were back again pretty quickly. The odds do not look good. Maybe the Blackbirds will try a bramble patch next time.

Below is another picture of one of the delightful Long Tailed Tits. I include it here just because I like the image – a bit Japanese print-ish – and it’s also the first time I’ve noticed the curious circular bokeh effect of the new lens.

I think Long Tailed Tits are becoming one of my favourite species.