There's a pair of lesser striped swallows (or their descendants) that's been nesting in a corner under our eaves for many years. One year their nest was washed down by builders engaged in paving our driveway, and a year or so back their abandoned nest was taken over by sparrows a month before their return at the beginning of November. Apart from those two years, despite our anxiety about whether they'll return, they settle in happily and raise their chicks before migrating north to the Congo.
Since the sparrows started causing squatter problems with the nest, we've taken to washing it down after the swallows leave. Each year on their return, if necessary, they spend about a month rebuilding their nest, completing it just before Christmas. When the chicks hatch, the parents spend the entire day hunting down food for them. They work as a pair, or in relays, flying in and out every few minutes. Their day starts at dawn, and they only stop at dusk.
They're incredible aerial acrobats, and swoop elegantly into the 60 or 70 mm diameter entrance tunnel of their clay nest at high speed, aborting at the last split second only if they see their mate already in the nest, at which point they divert to an alternative landing point of some security lights under the eaves about 5 metres away, or, less frequently, to the edge of the gutters attached to the fascia board.
It seems the same pair that returns - the only competition one year was from the larger swallows who are back somewhat earlier. On that occasion a pair of these swooped around various eaves looking for a place to build before l\departing and leaving things to the rightful owners. There's four phases to their occupation: on their return, they first inspect the corner and either reuse the previous nest or start the tedious process of rebuilding the octant of mud. The corner has a thick cable running into it along one wall, perhaps 20cm below the eave, and this is perhaps what first attracted them. It's just wide enough for them to perch on, and start construction. The nest is built from the bottom, then the lower edges and the beginning of the outer wall before the upper edges to the eaves are completed. Once this is done, they have a base on which to stand as they complete the outer wall up to the eaves. Their source of mud is consistently in one direction, but it's not obvious where in the neighbourhood they go, or what constitutes desirable building material. It can't be that far, as they're in and out every few minutes -- a frenzy of activity not unlike that when they're feeding their hatchlings. Both parents are involved in the building, which consists of spitting dollops of mud at the wall and hoping they'll stick..
While the actual dimensions must be ergonomically determined by the size of the birds, the only design parameter seems to be the tunnel entrance into the nest. Up until this year, it's been in the direction of the cable, which makes logistical sense as regards both construction and later access. The entrance is longer than expected, perhaps 3/4 the radius of the main nest.
This year was different, so perhaps these are not the original ones. Three swallows and not the usual two returned. After some fussing about for a day or so, two remained and started building, but this time the entrance faced towards the security light, and not along the cable.
The second phase, starting after nest completion in late December, is presumably egg laying and hatching, during which time the swallows catch food for themselves. They're in and out but more leisurely, and there's always one at home while the other flies off.
The third phase is signaled by an increased tempo of flying in and out, often simultaneously. One waits for the other, perching on the security light or gutter, before they zip off in pursuit of food.
Their flight path is optimised to just miss various obstructions, and they're elegant and minutely controlled flyers. Their return is not always simultaneous, and, after feeding a hatchling, the solitary parent often sits and waits for its mate, throwing back its head to make a sort of mixed chirp/squawk.
The fourth phase is the appearance of extra swallows on the gutter and the security light. Initially it's hard to tell if there are one or two extra. On closer examination, these have short stumpy tails, and they are enthusiastic but inexpert flyers, often missing their perch or the entrance to their nest. The chicks gain expertise quite quickly, encouraged by their presumably exhausted parents to get on with things. On the one occasion the swallows were able to reuse a nest, it seemed as if they had enough time to have two batches of chicks.
This year, again, things have been different. Two days ago after a lot of overnight rain we were having early morning coffee in the vegetable garden when my wife noticed the cats patting at something on the ground near the house. Concerned, she went to see what was going on, and saw that it was a baby bird, which she rescued. It looked suspiciously like a baby swallow, confirmed when their nest was revealed as having burst somehow, and showing another baby precariously perched in the remnants of the shell.
We'd been through a similar experience a few months before, when a baby drongo was spotted in the youngberry bushes at the side of the house. It was fiercely protected by its parents who swooped angrily and squawked at the cats every time they went out of the kitchen door, ultimately confining them completely to the house. The cats have a fearful relationship with the local drongos, who have terrorised them from kittenhood by sweeping in from nowhere and missing them by inches when their paths cross, then pursuing them relentlessly as they flee to the safety of the kitchen or beneath the truck, tails puffed up and ears pinned back.
The drongo chick, under the protection of it's parents made a complete circuit of the house and various recesses of the garden over the next day or two, We have a finely woven hemispherical wicker basket which was eventually roped into the lower branches of the mulberry tree as a makeshift nest. This was only temporarily successful, as the chick soon worked out it could hop onto the edge and flutter to the ground where it could resume its explorations. It was quite nimble and hard to catch, so after giving up after a few attempts at putting it into the basket, we eventually let it flutter over the wall into our neighbours cat and dog free backyard, and things settled down.
So, the basket was a possible, though unlikely solution to the collapsed swallows nest. My youngest daughter did the acrobatics of climbing a ladder and cable tying the handle of the basket to the cable against the wall, neatly fitting it under the remnants of the nest. The basket was padded out and half covered with a dish cloth, and the rescued chick placed in it, hoping for the best.
However, in the late afternoon, after the cats had been fed, my wife noticed to her surprise that there was a swallow chick unharmed on the kitchen floor. Clearly the cats considered this to be some sort of action toy, and not having the protection of drongo parents, it had been brought inside for their amusement.
My daughter, having left, meant it was my turn for ladders. Setting it up again in the corner I noticed the other chick sitting forlornly on a small rock under the nest. My wife passed the first one up to me, then captured the next which was also placed into the basket. By this time it was dusk, so we somewhat pessimistically left them to it overnight, expecting the worst.
Early the next morning, looking out of my bedroom window below the nest, I saw three swallows perched on the gutter, one with a short tail. It nevertheless flew diagonally to the other gutter a few times. When we went out, it was still on the gutter, while the other fledgling was perched on the handle of the basket. It remained there the whole day, being fed intermittently by it's parents, while it's sibling fluttered about a bit, also getting fed.
The older swallows at first were quite put out by the basket, being uncertain how to fly into it, but eventually worked out how to swoop in and out as effortlessly as before. The feeding process is surprisingly quick, the chick perched on the basket handle getting a mouthful without the parent even landing. By the end of the day, much to our relief, the swallow family seemed to have settled down, and the chances of survival seem reasonable.
The cats were kept inside the whole day.
Let's see how things develop.
Update 2017/02/10:
One baby swallow was still sitting on the handle of the basket this morning, looking sorry for itself. The parents flying in every now and then to feed it. No sign of the other, more active, youngster.
We decided it's OK to let the cats out, but after an hour or so this turned out to be a big mistake. When the parents returned to feed the youngster, they spotted the cats and went crazy, swooping at them and generally being panic struck. The swallows aren't drongos, though, and all this swooping around excited the cats who were leaping and jumping into the air trying to catch them rather than being intimidated.
In all the excitement, the inactive baby decided it was time to fly, and it's hesitant circlings just added to the cats enthusiasm. Eventually all the swallows flew off, and we spent a good half hour corralling the cats, who weren't keen on the idea of being cooped up in the house. Eventually they were again confined to quarters, but there was no sign of any swallows, so we got on with other things.
Now, at about 10h30, I've seen the swallows circling about outside my bedroom window. Time for a cup of tea and to go outside and see what's going on without letting the stir crazy cats out, quite hard to do.
Update 2017/02/11:
Gone for most of yesterday, and seen briefly, once, this morning.
Mission accomplished, I suppose... they've all survived and succeeded in doing what they're supposed to and now they're gone. A metaphor for life.
Suppose they'll be back at the end of the year to repeat the cycle.
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