Tuesday 3 June 2014

The mating dance of a non-native species

I'm back! Full disclosure: most of this post was written a few weeks ago, but I was so busy with my costume for MCM ComicCon that I didn't have time to finish it. ^^ But now the con season is over, and I'm back to finish the post, and add an update about how the breeding birds in my area are getting on.

Back a few weeks ago, my mum and I both had a day off, so we decided to go to one of our favourite nature reserves, Titchfield Haven near Fareham. Spring is a wonderful time to visit and watch the thriving Black-headed Gull colony (yes, the one I keep meaning to do a sketchbook post about- next post!) but of course they aren't the only species in the breeding mood. Though I don't think either of us expected to see what we did when we walked along the harbour to the visitor's centre and there were a pair of Black Swans among the Mute Swans, Mallards and Mallard/farmyard duck mixes!

Black Swans are a species from Australia that will definitely never arrive in the UK naturally, but they do escape from wildfowl collections a lot and there are quite a few in the country. Wildfowl collections are prone to escapes because the birds are usually not kept in aviaries, just on ponds with their wings clipped, and this wouldn't be the first time wildfowl from collections have turned up at Titchfield Haven! There's been such fantastic visitors as Fulvous Whistling Duck, Cinnamon Teal, a previous single Black Swan and a Cackling Goose, as well as a Canada Goose thought to be part Bar-headed Goose that was in the reserve's feral goose flock several years ago. The only one of those that might appear naturally in Britain is the Cackling Goose, which resembles a tiny Canada Goose, but it was clear that this one wasn't wild by it's complete lack of shyness as it fed with the Canada Geese a few metres from the hide. I've written a little about escaped ducks in this post where I talk about thinking I saw wild Red-crested Pochards on a village pond when I was about eight...so naive at that age. ^^

Unlike Canada Geese and Mandarin Ducks, Black Swans aren't currently a self-sustaining population, but apparently some are worried they will be the next Canada Geese and sweep the country with large, destructive populations! I don't see that happening, at least not in my lifetime, but according to the staff in the centre there are several feral Black Swans living on the Isle of Wight, a mere skip and a jump over the solent from Titchfield Haven, so that's probably where this pair came from. And as we watched them it became clear that they were thinking about the next generation!

The swans were facing each other with their necks gently curved, making the classic swan's-necks-make-a-heart greetings card pose, and then they began to mimic each other, with one dipping its head under water and back up, and the other doing the same a second later. Then the male moved closer to the female so his breast was touching her side, and looped his neck over her body and into the water on the other side. After he came up he kept his neck draped over her back, and all the time they were making little quiet calls to each other. Then the male slowly began to clamber onto her back so they could mate- actually he climbed on the wrong way round, but she was very patient with him while he slowly and carefully maneuvered his way round to face the same way as her. The actual mating looked a bit difficult and uncomfortable, with her back sinking into the water and him grasping onto the back on her neck with his beak, possibly to help him stay on, but it was over in a second and they broke apart, faced each other, both raised their necks straight up in the air and each gave a loud, triumphant call! You could see the middles of their necks expand out in a comical way while they called. The whole thing was an amazing sight to see, and took place about 5 metres away from the bridge we were watching from. I wished I'd had my camera on me- it's no good for photographing wildlife usually, but they were so close I could certainly have a taken a video of the whole thing!

The Black Swan pair continued to swim together, and later on we saw a Mute Swan pair swim a little too close to them. Suddenly feeling threatened, the Black Swans split up, and each took a Mute Swan to chase, flapping and splashing aggressively and successfully seeing off the bigger swan pair! We wondered if the male chased the male and the female the female, but as Black Swans appear to be sex alike it wasn't possible to tell- I only identified the male in the mating dance from his role. While the male Mute Swan is bigger than the female with a larger lump on his bill, and sometimes holds his wings raised over his back to look bigger, the Black Swans were both the same size, both had the same red bill with a white stripe on it and the same gorgeous, wavy feathers on the base of the back. I've heard Black Swans described as ugly but their plumage certainly isn't- I think it's the rather odd, contrasting bright red beak that gets people. Black Swans have white primary feathers, and I noticed when they flapped at the Mute Swans that at least one of them had no clipping on its wing feathers, suggesting it had moulted at least once since escaping!

Whether or not this pair made a good choice for their nest site, incubate well, and get lucky with the weather and predation (they may well be inexperienced), it was just so fascinating to watch such a natural Spring behaviour as courtship and mating in these captive born birds. I've not seen courtship displays in very many British birds- I've seen Great-Crested Grebes do their beautiful mating dance just once in my entire birdwatching history, and I've seen Buzzards flirting in flight, and Woodpigeons billing and cooing, but there's not many other birds that I can remember watching courting. I did very much enjoy seeing Avocet courtship on Springwatch the other night, though! It involved delicate splashing with the long, beautiful beaks, and then a sort of wing-hug after the actual mating. ^^ Such amazing birds. At some point I will cast my mind back to 2011 and write about the time I saw baby Avocets...


Speaking of Springwatch, I wrote last time about the baby Blackbirds in our garden, and like Springwatch I am able to give you an update! I was a little concerned to see one baby being fed several times in a row, but this was not a long term problem, and both babies were seen again, getting more confident all the time. What's more, they were joined by a third! Soon the babies were no longer hiding in bushes but were joining the adults on the ground feeder. At first they begged their parents constantly for food, and then they began to peck at the food themselves but only when the parents weren't around. As soon as a parent would appear, the babies would completely forget about their newfound feeding independence and beg shamelessly, opening their still visible gapes and peeping and wing-fluttering..it was quite hilarious to watch, and the poor parents were so frazzled!

Blackbirds have multiple broods, and it didn't take long for the female to stop attending the babies at all, as she was no doubt concentrating on brewing the next clutch of eggs, and probably renewing and strengthening the nest after the strain of having had three large babies wriggling about in it. When it comes to feeding, impressively she sometimes uses one of our sunflower heart feeders! Thrushes are not really built for feeders, but she can stay hanging on long enough to gulp a few down. The sunflower hearts also proved a good meal for the babies as they began to feed themselves in earnest, as they were able to peck up all the seeds the messy finches are always dropping. The male was still around keeping an eye on the babies in a sort of hands-off way, and though they still pestered him for food when he was around and he'd sometimes feed them out of habit, they were really almost fully independent. They were flying properly, their tails were almost full length (if a little wonky and scruffy), and their gapes were almost gone.

It was just about at this point when another baby Blackbird appeared in the garden! This one was a really young one, with the tiny tail, speckley breast and giant yellow gape. The female of the first brood was still absent most of the time, probably incubating her second brood, so this wasn't the original Blackbird pair's baby but from a new brood, and a different pair! It was really funny seeing the contrast between the slightly older babies and the new one.

Next baby bird to appear was a young Starling, joining the adults on the ground feeder. I'd been looking forward to seeing the first baby Starlings ever since I found the eggshells I wrote about last time, and was so happy when the day finally arrived! The juvenile Starling didn't have the scruffy feathers the baby Blackbirds had, but was just as slim and streamlined as the adults, though light grey all over. I couldn't see any external gape, and its begging technique was different from the baby Blackbirds- it didn't flutter or peep, but just sat there with its great, gaping beak open while the adults stuffed in food! Its beak was bright yellowy-orange on the inside. There were at least 3 adults on the ground feeder with the baby so it wasn't just with its parents, but none of the adults seemed at all worried about each others' presence or the baby's presence, showing the Starlings truly are flock birds, even in the breeding season. This is in stark contrast to Blackbirds, who don't flock in the breeding season, and in fact the father of the first Blackbird babies got into a rather violent scuffle with another Blackbird (probably the father of the second Blackbird babies as I doubt there's room for any more Blackbirds around here!). It was a proper pecking, rolling around and clawing fight and something I've never seen. It was hard to tell who won, but 'our' Blackbird (the father of the first babies) has been looking a bit worse for wear every since, as he lost a whole chunk of the feathers on his forehead. A few weeks later, he's still like that, but now the poor guy has also had an encounter with (probably) a cat, which cost him all of his tail feathers! It's sad to see him wagging his behind automatically, and having no tail to flourish proudly. The moulting season is coming up anyway, though, so he should soon be growing new ones. And until then there's plenty of food about.

Next to appear was an adorable baby Robin, and two scruffy baby Dunnocks (they have pink beaks! It's weird). Then a couple of weeks ago, there were yet more baby birds in the form of a beautiful (and HUNGRY) Great Tit family, and then the Goldfinches were next, with three beige-faced youngsters watching the adults on the feeder and begging shamelessly for food. Young Goldfinches may not have the black, white and red face pattern of the adults but they already have the yellow wing bars that makes Goldfinches so distinctive. Young Great Tits have the same pattern as the adults but they have yellow cheeks, as do young Blue Tits. When I was younger I saw a picture of this in a bird book and was surprised to see that the youngsters seemed even more colourful than the adults which didn't seem a good idea for baby birds, but when you actually see them the effect of the yellow is to tone down the contrast on the head pattern, turning black and white into black and pale yellow. This, combined with an overall 'desaturation' of the colour on the rest of the feathers means they are far less noticeable than the adults. We don't think either of these species nested in the garden or all that close to it, but we're glad they came to our garden to feed their hungry young. :) Goldfinches are everyday visitors to the feeders, but before the babies came the Great Tit was seen only occasionally this Spring, usually in the evening when it would stop by for a quick bite to eat at the feeder.

And this evening, I looked out of the window and saw tiny, ball-shaped birds whizzing around the garden- it was a Wren family! The babies perched in our hedgerow and wildflower area, occasionally fluttering from bush, whirring their little stumpy wings at top speed. Despite their tiny size the yellow gape at the edges of their beaks was very visible. We counted three young attended by one adult, who by contrast looked very sleek and confident as it balanced expertly on small stems to pick little insects from under the leaves.

At my local patch, I've seen baby Robins (out on their own) and a baby Great Tit (fiercely attended by a noisy adult with an extremely wide black belly stripe!), and best of all, last visit there were three young Long-tailed Tits! I couldn't see an adult and they seemed pretty much independent, and they already had full-length tails, but the big smudge of black over their eyes gave them away. It really emphasised the orange eyes Long-tailed Tits have. I've found Robin eggshells and, more unusually, the vivid bright blue of a Song Thrush eggshell. Song Thrushes aren't unusual of course but I rarely ever see them on my patch, or hear them, with the only singing male I've heard there coming from far away, possibly from a garden on one of the suburban estates at the edge of my small arable farm patch. In my egg post I talk about the Starlings dropping their hatched eggshells away from the nest, so maybe a thrush flew all the way in from a neighbouring garden to really throw predators off the scent?

The male Whitethroat is back in his usual singing spot, and the male Yellowhammer is singing in the hedgerow, both familiar from last year (this is only my second Spring watching this patch) but there's a new player in the form of a lovely Goldfinch pair who I suspect are nesting in the shrubs below the mature trees in the middle of the farm. The Skylarks are hovering and landing on the fields a lot, and it's exciting to think that somewhere in the sea of green crop are hidden eggs. The Carrion Crow pair are back in the same patch of trees as last year, but not in the nest I found last year, which I suspect blew apart in the winter storms. They have a new one, more deeply hidden in the trees, and now both members of the pair are flying around again which I suspect means the babies have hatched! There's a Jackdaw pair around that area, and a Magpie pair in the trees at the edge of the farm.

Finally, the House Martins, who nest in the area but not in the actual patch (perhaps on the estate too), are visiting their favourite mud puddle on one of the paths to pick up mud for their nests. At one point I counted 17 landing there all at once! I always hope that I'll see their tiny footprints and beak marks in the mud, but I haven't yet. They are extremely light, after all!

How is the breeding season shaping up in your area? Are there baby birds in your garden, or at your patch? Tell me all about them! :)

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