While I love this blog, I now pretty much only write on my other two blogs: BirdingBlogs.com and 10,000 Birds - I would love to see you there!

Friday, 25 April 2008

Alpine Swifts

I remember the day I first saw an Alpine Swift (Alpensegler, Apus melba). It must have been around Christmas time late 1990 or so. Hot. We were just driving in to downtown Durban as a wave of swifts shot over the car. Swifts everywhere! What a sight. As usual, most of them were whiterumped and little swifts (Kaffernsegler und Haussegler) but then these HUGE swifts came by. They looked like mammoths zooting across the sky. And with that bright white belly! I knew exactly what they were almost before I had even seen them.

Over the years I got more familiar with them. Dawn cape parrot counts overlooking Hlabeni forest were often greeted by the swooshing of razor-edged wings as they sped past our faces. Breathtaking. To say the least.

I was reminded of these lovely birds the other day when I found the most incredible photo-blog by Graham Catley. He had posted three images of Alpine Swifts feeding on the wing - some of the best swift photos I have ever seen.

And then yesterday afternoon I was peering outside (as I am wont to do) and there was a whole group of them feeding over the houses in eastern Zirl. There movements are so graceful, so, well swift. It seems they are just returning from their migration to Africa and we will hopefully see a whole lot more of them over the coming months, particularly in the mountain regions.

The photo that shows all the swifts circling the town (its just a wiki commons photo so I don't know where it is from) is often how you will see them - dashing quickly about. They are hard to track with your binoculars but their large size and white breast is likely to make their identification somewhat easier. Interestingly, while swifts (Segler) may look like swallows (Schwalben), they are only very distantly related. The easiest way to tell the difference between the two in the air is to look at the wing shape - swifts have long, thin wings that make them look like darting boomerangs. The swallows have a rounder wing shape, not as sharp as the swifts.

The swifts belong to the order Apodiformes (meaning no feet. hummingbirds are also in this same order), an apt name for a bird with such tiny legs and feet. Talking about feet, the difference between swift and swallows is immediately obvious when one has them in the hand. Swifts have pamprodactyl feet which means that both the first and fourth toe can swivel forward so that all four toes are in a row. This helps the swifts cling to the cliffs when they (very occasionally) land. You can see this clearly in Prof David Norman's photo, left. The swallows have decidedly longer legs with normal bird feet, i.e. three toes forward one back. The swallows are much more likely to perch - they are the ones that you see sitting on telephone lines alongside roads and fields.

Alpine Swifts prefer to breed in cliff or cave nest sites, and generally lay two to three eggs. The adults feed exclusively on small insects caught on the wing, which means that during cold and wet periods, flying insect food can be severely limited. Incredibly, it seems that the chicks are able to survive these enforced fasts by reducing their body temperature (torpor) and by mobilizing the energy in their relatively large pectoral muscles (Bize, Klopfenstein, Jeanneret & Roulin 2007 Journal of Ornithology 148/4).

If you are interested in their breeding, check out the webcams of two Alpine Swift nests in southwestern Germany.

Happy birding, Dale Forbes

Monday, 21 April 2008

The Ptarmigan

I found this gorgeous image on Flickr and really wanted to share it (click on the link to go to the original site). Leafing through my bird book a few months ago, I saw the Ptarmigan (here, better known as Alpenschneehühn Lagopus muta) and I was struck by its stark beauty. There are very few pure white animals in the tropics, and they really do stand out when you see one so, I must admit, that I have a natural draw to beautiful white birds. And then, quite unexpectedly, I was snowboarding at Patscherkofel one day, and a group of five startlingly white Ptarmigan flew over. A few weeks later, I got to see some in Serfaus-Fiss-Ladis, and again in Kühtai. It seems that they really like the areas near the top of the tree line (about 2000m) or higher. In spring, they lose their lovely white plumage for a better camouflaged brown flecking, and the males get a bright red comb. The brighter and bigger the comb, the better his chances are of successfully breeding!

So, if you happen to be high in the mountains, always keep a look out for these little guys as they fly around in their little groups.

Happy birding
Dale Forbes

Sunday, 20 April 2008

Goldcrests and firecrests flitting through the trees

There were a bunch of little goldcrests out this morning. Very shy, flitty little birds. Apparently they are the smallest bird in Europe. Well, they are certainly not large! While the rest of the BirdLife Austria group was chatting, I took some time to follow their movements to try to see a little of their characters. I found one little guy collecting nesting material - darting all about, here and there (they certainly are flitty little birds). I suppose this guy was building his nest in the heavy, leafy ends of one of the conifers - hiding the next generation away in its dense, protective cover.

Incredibly, the female goldcrest (Regulus regulus, Wintergoldhähnchen) incubates the eggs alone and is not regularly fed by the male and the total mass of eggs can be 50% more than her body weight (Haftorn 1978 Ornis Scandinavica 9)! Despite doing it all along, these little 5gram females are able to keep the temperature of her brood remarkably constant, by varying the amount of time she spends on the eggs (and away from the eggs)(ibid).

A very closely related species to the goldcrest, is the equally adorable firecrest (Regulus ignicapillus, Sommerhähnchen). Both are exceptionally flitty species; never sitting still and always darting from one branch to another. And even when they do seem to be on one branch for more than 10 seconds, they tend to flap and shake their wings. This is typical behavior of small insectivorous birds (willow warblers, tree creepers, white-eyes and many others also do this). By flicking their wings, the sharp movement tends to startle little well-camouflaged insects just enough to get them to move. And even if they move just a wee bit, the sharp eyes of the insectivore will spot them (and eat them for breakfast!). But despite looking very similar and both feeding on small insects, it seems that their territories can overlap extensively (no interspecific territoriality) and they differ in how they feed (Leisler & Thaler 1982 Annales Zoologici Fennici 19/4).

To tell these two little guys apart, birders look at their cheeks: the firecrest has strong black and white eye stripes (see left). Compare this to the plainer cheeks of the goldcrest above. But even easier than trying to look at their make-up is to just listen to them: they both have very distinctive calls. Try these links to the RSPB site to listen to how they sound!


Happy birding,
Dale Forbes

Thursday, 17 April 2008

The Warblers Are Back

The gorgeous little Blackcap (Mönchsgrasmücke). I had been wanting to see one of these for years and years and years. But, South Africa is not famous as a major Blackcap destination. In fact, as far as I can tell, only a couple have ever been seen in the sub-continental region (the story goes that the first blackcap ever found in the region was actually caught in a mist net near Johannesburg!).

And so, along with the joys of seeing all the other migratory birds returning home, it is great to finally meet the blackcap. Last week there were none. This week, they are like sparrows falling out of every bush!

It seems that in preparation for migration, young blackcaps (Sylvia atricapilla) move about completely randomly as they search for food to fatten up for the migration ahead (Chernetsov 2002 Journal für Ornithologie 143/4). The ones that migrate down in to Africa tend to follow the high mountain ridges. At regular stop-over points, the blackcaps settle to rest and try to feed a little. At this stage, they seem to remain within a fairly restricted area (i.e. not wandering off too far), but the area is too large to be considered a defended territory in any way.
Interestingly, blackcaps reliably use fruit color to determine the levels of anthocyanins (an important antioxidant) in fruit, and the anthocyanin level is also correlated with the total calorific content of the food (Schaefer, McGraw & Catoni 2008 Functional Ecology 22/2). Thus, blackcaps are able to select the nutritionally most advantageous fruits based on fruit color. But if only unripe fruits are available, blackcaps tend to rely more heavily on insects for food (Schaefer & Schmidt 2002 Journal für Ornithologie 143/3).

Dale Forbes

Sunday, 13 April 2008

Yellow wagtails, grey wagtails and great big Golden Eagles!

I have always had an interest in wagtails. There is something about their nature that always caught my eye. That calm demeanour. And a ritualistically wagging tail. It is like looking at a monk calmly chanting his maha mantra. I remember being fascinated by the little cape wagtails that visited our garden as a child. Scoured every brook for a longtailed wagtail, and never failed to point out the odd pied wagtail. A little later, the pipits (basically ridiculously difficult to tell apart brown versions of wagtails) drew my attention.

This morning we went out on a joint walk with BirdLife Austria, and WWF to Schloss Tratzberg to walk about in the fields and stream-side habitats. Early on, we found a few cute little birds; some of my favorites being the european blackcap and the jackdaw. But when the sun started to rise in the sky, and the day started to "warm" up a bit (all relative of course - the snowy peaks do not lend themselves to warm mornings), the wagtails started to come out.

A gorgeous grey wagtail presented himself for examination alongside a little stream. Our competant guide Andreas Schwarzenberger regaled us with his trick to telling the grey from the yellow wagtail: "It's easy" he said "just look at the colour of their back." You see, both species are rather variable in their coloration but their back color is always rather constant: if it has a greenish or brownish back, it's a yellow wagtail, and if the back is grey then (you guessed it), it's a grey wagtail. Easy when you know how!

The day's highlight was, for me, two gorgeous golden eagles. Granted, I am prone to exageration. But these birds were absolutely incredible. They were way up, circling the peaks and they still looked impressively large. One of the birders had brought along his Swarovski telescope, affording us great views as they circled in and out of the morning mists. Previously, I had thought that they may be somewhat difficult to tell apart from other large raptors, but their distinctive eagle wing shape and their sheer size gave these guys away in a snap - keep a look out for the bulging trail edge to the wings (thanks Andreas!), and the enormous wingspan.

To add to the day's raptor tally, we also saw a couple of black kites (sorry, couldn't resist noting them here), a steppe buzzard and a pair of greater kestrels (being mobbed by the jackdaws).

All in all, a lovely morning.

Dale Forbes

Tuesday, 8 April 2008

A Black Kite!

Wow, sweet!
I went for a mtn bike ride this afternoon along the Inn and saw some pretty cool things wizzing by. (that is me trying to convince you that I ride fast - did it work? I didn't think so, I had trouble convincing myself as well).
I did, however, get some great views of a black kite that was scouring an open field near Mötz. I really loved always having the kites around when I was growing up and every year we would check the sky religiously at the beginning of August (did I remember the month correctly?) to see when we spotted the first kite. Invariably, they would be seen on the northern KwaZulu-Natal coast first, then around Durban, working their way up the N3 towards Johannesburg and then explode throughout the country. It was always rather dramatic and certainly very exciting.

So, seeing my first kite of the northern hemisphere season brought back lots of happy childhood memories. Now, I am not going to get all pop-psychology on you, but it was rather cool. I hope to see more. Soon. I must say, it is fascinating to see all these species that I knew from southern Africa migrating here, and seeing them here in their "other" home. It brings a whole new dimension to my birding life.

The Alpine Winter was, however, a rather dull time for birds. My bird list remained static for months and I was forced to amuse myself with other hobbies. (skiing and tobogganing are, luckily, more than a little fun, so I was not too depressed). But now, with the onset of spring (oh, if someone sees the manager in charge of the weather, would you please tell them to turn the snow machines off already!) we are seeing lots more birds about. and they are all singing. the blackbirds sing their beautiful Turdus lyrics and the crows are building nests. Oh, and if you have never seen a Gold Finch Carduelis carduelis (here they call it a Stieglitz) then do yourself a favour and find one! Their lovely little white-rimmed scarlet faces makes them looks like they got a little too excited about the whole lipstick thing and permanently ruined their porcelain white doll faces.

The sun is due to make a bit of an appearance this weekend so I plan to take the plung and dust off my swarovski's and hit the woodland. If you live in the Alps (or anywhere else for that matter) you should probably do the same because, honestly, what can be more rewarding than finding a pretty little finch to look at as it fluffs itself up for the ladies!