Bird ringing course at Botuin, Vanrhynsdorp : 15 to 20 November 2024

The BDI’s 10th bird ringing course was held at Botuin, Vanrhynsdorp, from 15 to 20 November 2024. We have a selection of ringing sites in the district, which we use in rotation during our trips. We are trying to reach a point where a good proportion of the birds at these sites are ringed, and over a period of years we will be able to collect enough data that we can make, for example, estimates of survival rates for the bird species here. The importance of the data which we are collected is summarized in this blog The Value of Bird Ringing to Research and Conservation.

One of our favourite sites in the Botuin district is “the lark site” at the foot of the Maskamberg, commonly known as the Gifberg. This block of rock has an instantly recognizable profile. When you see it, it screams “VANRYHNSDORP” (which, when rewritten for English speakers, is pronounced FUN-RAINS-DORP).

So this blog opens with a series of images of “the lark site” which hopefully captures the spirit of the place.

By November, the area is taking on summer browns. In contrast, here is a winter green, with a long line of mistnets.

We never catch many birds here, but we do get information on birds we never occur at the “easy sites”. On this morning during the course the total catch was 11 birds, of seven species: Large-billed Lark, Karoo Chat, Karoo Scrub Robin, Grey-backed Cisticola, Red-billed Quelea, Southern Red Bishop and Karoo Prinia. Of these species, the ones we only obtain at this site are Large-billed Lark and the Karoo Chat.

Another ringing site in the area, new to us in the sense that we have not fully explored the opportunities here is on Maskam Farm, which in early spring has magnificent displays of flowers, and is open to the public. From the bird ringing perspective, there’s a variety of habitats, including a small farm dam, gardens, and areas like this, where the vegetation is of uneven height, but the tops of the tallest shrubs are at mistnet height:

Sewage works are an irresistible magnet for birders in general and ringers in particular! In arid areas, the sewage works is frequently one of the only places with open water.The sewage works just outside Vanrhynsdorp is no exception.That is a Maccoa Duck on the pan in the photograph below. Besides ducks, coot, moorhens, crakes, etc, the reedbeds at the sewage works provide roosts for bishops and weavers, and those are our main target species here.

Doing a ringing course in November is is especially good it you want to learn about moult. More and more, we are making photographic records, and below is a selection from an awesome collection made by Toni Hoenders, attending the course from the Netherlands, where she is a trainee ringer.

The Hoopoe above has completed primary moult. The 10 primaries (the all black feathers) have tips which are clearly demarcated and unfrayed.

Laughing Doves have 10 primaries. On this dove, the division between the primaries and the secondaries is obvious. The lighter grey secondaries all have central shafts that curve a bit to the right. Primaries one to three have been replaced, and they are the three dark grey feathers, and because they are grown in sequence, the third one is the newest. Then there are six old primaries which have had a year of use. Three + Six = Nine. So there is a primary missing. It HAS to be primary four, just outside primary three, so the six old primaries are numbers five to ten!

Look again at the three longest primaries of the dove, numbers five, six and seven. When the dove is settled, with its wings folded, the tips of these feather are exposed. You can see the impact of the sun. The last few millimetres of these three feathers are faded. When the dove is settled, the outer primaries are folded away under the other primaries, so they don’t show this pattern.

The outer five primary feathers of this Lark-like Bunting are faded compared with the inner primaries. So they are old, even though they are not particularly ragged at the ends. Lark-like Buntings have nine primaries. The outer five are old, so we are looking for four more. The brown feathers on the right are secondaries, with slightly curved shafts.Two new primaries are clearly visible. Neither is full length yet, so they are still growing. A little bit of primary three is visible under primary two. It is a bit less than half grown. So the missing fourth primary has to come next, and it HAS to be in the gap just before the old primaries, which must numbers five to nine.

Getting to the end of this primary moult tutorial. Southern Red Bishop has nine primaries. The seven outer primaries are visible, and old. Therefore we are looking for two more. The big feathers on the right are all secondaries; shafts curve right. Therefore primaries one and two must be in the gap. Because the feathers grow in sequence, that half grown feather must be primary one, with primary two, still invisible, alongside it.

In this photograph, you can see how the feathers grow. That blackish sheath, at the base of the growing primary, is the scene of the action. That is where the growth takes place, and the part of the feather grown so far is what moves slowly outwards. So the tip of the growing feather will ultimately become the tip of the feather, and will line up with the rest of the wing. Moult is an energetically expensive process; the little feather factories are a complex chemical plants, demanding both a supply of raw materials and the energy to turn them into feathers. Every feather has its own chemical plant at its base, which needs to swing into production once a year to replace feathers.

Birds don’t always moult their primaries in the conventional order, from the inside, moulting the outermost primary last. This Southern Masked Weaver above is a puzzle. The superficial classification says “no moult”. But look a bit more carefully. Weavers have nine primaries. The outer three, primaries seven to nine, are new. They are a dark colour (the others look faded), and the edges are neat. Primaries five and six look the oldest of all; the tips are worn, and frayed. Primaries one to four look in better condition, but are also faded. The secondaries are the next six feathers; they bend a bit to the right. The outer five secondaries look newish, unfaded. The sixth secondary (the innermost, above the tip of the finger), looks a bit faded and is therefore probably older than the other five. We can only guess what stresses this bird has endured.

Birds use their tails mainly for steering, balancing and breaking. Tails often have 12 feathers, and they are also replaced annually. The order of tail feather moult is often quite variable, but mostly starts with the central two tail feathers. In this Southern Marked Weaver, only eight of the tail feathers are visible, and they are obviously of very different ages.

The table shows the species handled during the course, and the numbers ringed or retrapped of each species. The total as 261 birds of 29 species, and an amazing 96 were Larklike Buntings.The species in red in the table and underlined have structured species texts in the BDI website. Click on the species and you get taken to its text.

The Cape Bird Club sponsored the attendance of two students at the Cape Peninsula University of Technology (CPUT) at the course. Muneeba Lamera and Amy Lewis wrote an appreciation to the club for the opportunity, which was published in Promerops, the newsletter of the Cape Bird Club. Here it is, extracted from Promerops 331, March 2025: