The first day of CES

Today was the first day of the Constant Effort Ringing (CES), in which we set up a large number of nets at two sites within the reserve. Each site is run for 3 days, alternating between the two. The nets are opened at first light (5.45am here) and we usually ring until 10:30. The CES is run 5 times throughout the year and gives us valuable information about the breeding, moult, survival and residency of Amurum’s birds. Check out the research section of the APLORI website for some of the results from long-term ringing at APLORI.

Ringing is a big passion of mine and I really enjoy the CES. It is a great opportunity to see many of the species here ‘in the hand’ and there are always nice surprises. Today we started at the site around the guest house where I stay (so conveniently close to the coffee pot), and tomorrow we will ring down at a site further into the reserve. I was a little apprehensive as it has been a while since we ran a CES and so we were likely to catch lots of birds, but in fact captures were steady. This is just how I like to ring – busy but with plenty of time to appreciate the birds. Tomorrow’s site is more akin to grassland savannah, and I anticipate plenty of Cisticolas (a group of very similar-looking species that are always a challenge to identify) and of course Northern bishops. Bishops are a treat at this time of the year, with the males now kitted out in stunning red breeding plumage. They are a rich scarlet and deep black with a wonderful texture, not dissimilar to your finest fleece, and their red napes stand proud behind their heads. It is hard to remember them as they were in the non-breeding season with the males matching the drab females. 

 A superb specimen of a male Northern Red Bishop in breeding plumage

Bird Of The Day for me was a Red-winged warbler. I remember seeing this bird for the first time the day I arrived at APLORI in 2011 and it is still as stunning now, with its brick-red wings, slate-grey head and cream belly. It is really beautiful. Other highlights were 5 Snowy-crowned Robin Chats, Blue-cheeked Cordon Bleus, Bronze Manikins, a Black-crowned Tchagra, an African Yellow White-eye and a male Northern Red Bishop. Evolution did a superb job when designing the colour scheme of each and every bird I know, and you really can admire them this close up. If I dressed in the bright red and cyan blue of the Cordon-bleus, or mixed green and red like the Scarlet-chested Sunbirds, you wouldn’t be seen dead with me! Although I have to admit that the Yellow-fronted Tinkerbird is stuck in the 80s.

A picture-perfect Red-winged Warbler

We also caught some migrant Garden Warblers. These are long-distant migrants from Europe, like the Whinchats and Whitethroats, and pass through earlier than other species. Garden Warblers are known for being ‘non-descript’ and birders use the fact that they have no distinguishing features to distinguish them... it sounds odd but it works. They are very gentle looking birds and another favourite of mine. They can also be a bit of a challenge to age, but the more you see the more obvious it gets. For this species, it is a matter of looking at how worn the feathers are. Adults moult once a year after arriving on the wintering grounds (quite unusual for European species), and so the adult birds we were catching had used their feathers to fly to Europe, breed, and then all the way back. Understandably they were looking a little worn around the edges to say the least. Juvenile birds, however, grew their feathers in the nest earlier in the summer and were looking a little more dapper. Ringers generally use moult and plumage to age birds because juvenile and adult birds change different feathers at different times of the year. Knowing the age structure of the population gives us vital clues to the ‘health’ of the habitat, survival rates between adults and juveniles, and of course breeding success. In conservation, this is vital information. Fewer juveniles to adults, for example, may mean reduced breeding or high juvenile mortality. I am known amongst my ringing friends as being a bit of a geek when it comes to moult, but in my defence it is incredibly fascinating. You really have to look at the finer details, and I love a challenge. 

Today I was joined by Chima, one of last year’s Masters students who is helping out with the CES. Chima started ringing less than a year ago, and it is a pleasure to see him as the enthusiastic and competent ringer he is now. Ringing is a difficult skill to master. Not only must you be capable of collecting data safely and accurately, you must also have a good understanding of the moult and life-histories of the birds you catch. Most of all, it requires patience and you have to know your limits. Although I have ringed thousands of birds, I always learn something each time I ring, and I still have lots to learn. Today the 5 robin chats provided a great exercise in ageing as we caught birds belonging to each age class. This species has a distinctive plumage as a juvenile, and whilst adults change all of their feathers when they moult, juveniles keep some of their distinct feathers. The result is what is referred to as a ‘moult limit’, and we use this to tell how old the bird is. You can see this in the photo below of a bird that was born earlier this year, as it has both adult (blue-edged) and juvenile (brown tipped) feathers.

 An example of a 'moult limit' - the first 5 feathers from the right are juvenile, the rest are adult

Tomorrow should be an exciting day with plenty of challenges so an early night is in order. I may put playback for whinchats at some of the nets as we sometimes catch this species here.

Emma