Saturday, 6 October 2012

Ringing delights

We have now run the CES for four days, two at each site. Captures are a lot lower than I expected, but I prefer it this way when there is a steady stream of birds coming in. It's just right - having time to appreciate each bird individually is always a sign of a happy ringing session. Birds are still busy breeding so things will be different by the next CES at the end of November. If last year is anything to go by it will be quite busy.

Ringing at APLORI is brilliant because of the diversity of species we have here. I am lucky to run two sites in different habitats, and not surprisingly the species caught differ between them. At the guest house site we catch more of the smaller finches, thrushes and birds which prefer more wooded vegetation. In the grassland site it is Cisticolas, Bishops and surprisingly more Sunbirds than one would expect. Today's highlight: a stunning male Yellow-mantled Widowbird in his glorious breeding plumage. Normally these are drab brown birds very similar to female Northern Red Bishops, but at this time of year it's all about looking your best.

Now that is what I call breeding plumage!

The migrants are still arriving, and today saw the first Willow Warbler of the season. These tiny birds fly all the way from Europe to South Africa with less then 10 grams to their name. Also around and in the nets are Pied Flycatchers, more Garden Warblers and Wrynecks. I was lucky to spot a Wryneck out birding yesterday. In the field they are a somewhat unusual bird, but in the hand they are just plain bizarre. You will see from the video below why they are called Wrynecks. It's enough to make you feel dizzy!


 


It is a little unfair that I get all the fun, so for those at home, here is just a handful of the stunning birds we have been lucky to see during the CES so far. Enjoy!



Scarlet-chested Sunbird
Little Bee-eater

Rock Firefinch
Yellow-crowned Gonolek

African Blue-flycatcher
 
Variable Sunbird
 
Red-cheeked Cordon-Bleu
 
Lavendar Waxbill


Viellot's Barbet
Don't get your fingers near this one!
 

Yellow-fronted Tinkerbird

 
Snowy-crowned Robin-chat
 
The new APLORI Masters students trying out thier new binoculars

There are two more days to go next week and then it's back on with fieldwork. I am excited to get back to the Whinchats. I wonder if more have arrived? I still haven't managed to out-wit the ringed bird, but I haven't played all my cards yet. This bird is valuable for the study and I am determined to make sure it has colour rings by the end of the week.

Emma


Wednesday, 3 October 2012

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

Friday, 28 September 2012

Back into the swing


I am pleased to announce that there are now 4 new whinchats with colour rings. I haven't caught the ringed bird (yet), but there is plenty of time still. It is a relief after yesterday. It’s usually the case that the first day of fieldwork doesn’t go to plan and yesterday was no exception. After a long morning I just couldn’t catch any of the birds and came back frustrated. Let's hope that yesterday was just ‘one of those days’ after the good day today.

 One of today's 4 new whinchats, still in beautiful plumage even after flying over the Sahara. One of the birds, hatched this year, was in such terrible condition I wondered how it made the journey. I hope it gains condition before making the return flight.

Things do seem different from last year and I think it is because it is still early and the ground is wet and the vegetation thick. It is tricky to find a good place to put traps. Yesterday we set them at the edge of a corn field where 3 birds were chasing each other, plus two more sets by other birds in the area. For the whole morning the birds did not really respond to the playback. Everybody seems very intolerant of their each other (and of me) and all around there are whinchats chasing each other and ‘ticking’ - their way of showing their irritation at trespassers.

The fieldsite after the rains. There is little bare ground and the vegetation is 
green and lush - a far cry from when I left it in April.

This morning we decided to take a different approach and set mist nets in the tall maize. These very fine nets are almost impossible to see amongst tall vegetation, providing you work before sun and breeze give them away. To my surprise they worked well and 3 of today’s bird were caught in the nets. I will take advantage of the maize before it is harvested in late October. The more birds I can catch with nets the better, as it might well be a case of ‘once bitten, twice shy’ with the spring traps. Normally, ornithologists use mist nets to catch small birds like whinchats, and I will indeed use them for whitethroats later in the season. Sometimes, however, it is not possible to use nets because the habitat is too open, or perhaps something else works better, like spring traps. Both methods are good for different situations, and most importantly they are safe for the birds. The word ‘trap’ does sound a little harsh, but these are brilliantly designed and work a treat without stressing the bird.

On the left is a set trap showing the trigger, which when pulled springs the netting shut (as demonstrated by the cotton bag on the right). The playback is put nearby.

For whinchats, spring traps are perfect as they take advantage of the bird’s natural behaviour. Whinchats typically perch on the top of small bushes, flying down every so often to pick prey from the ground. They are also territorial and so will respond to the song and calls of whinchats. Birds use song and calls to attract mates, broadcast territories, announce the presence of a predator and to let each other know where they are. Consequently, birds will often come to investigate the songs and calls of birds of their species. Whinchats are no exception and treat the sound of another whinchat as the presence of an intruder. Using ‘playback’ simply means playing songs and calls to get a bird’s attention. With this in mind, it is relatively straightforward to catch a whinchat. You will need:

whinchats
4 or 5 spring traps
live bait (the wigglier the better)
playback
a small isolated bush
equal parts patience and perseverance
a sprinkling of good luck

The key is to use the playback to get your bird to come near the traps. If the traps are placed where the bird will see the baited triggers, they will fly down to feed, spring the trap and you will catch your whinchat. A small bush on its own is best - that way the bird is close to the ground (and your traps) and not perched far away. I use maggots for bait as they definitely tick the wiggle box and are marvellously resilient, even under the African sun (you get used to them after a while, getting hold of them is the unpleasant bit!). Getting all of this right is often trial and error and you have to move to a different bush (or 5). Some birds are just not bothered to too suspicious to catch. Some are so territorial that they will perch immediately above the playback and become so transfixed that they ignore the bait. The worst culprits will perch on every single bush apart from the one with the traps underneath. I'm sure these birds are deliberately trying to wind me up! Getting it to work is rewarding, and I am always excited to check the traps. Whinchats are brilliant little birds to ring as they are a bit of a challenge to age and sex (but almost always possible) and have an air of robustness and resilience about them that is reassuring to any ringer. Plus they are really gorgeous.

I am off to take a tentative drive down to my other sub-site. I suspect that the road is undriveable so it may be that I will have to wait to see if my birds have returned. I am excited to see this site. There is a river running along one side and I often see great birds there.

Emma

Wednesday, 26 September 2012

Old friends


After two more trips into the field (kitted out with a new pair of rubber boots) I have found 4 more colour-ringed whinchats from last year. These birds are again in or very close to the same tiny territories they held last year. It’s like they never left. This brings the total up to 7 so far, and I am confident that more will show up as the weeks progress. It is still early and it is likely that there are more birds that I haven’t found. It is quite easy to miss birds when re-sighting as they only need to be on the wrong side of a bush or foraging on the ground for you to not see them. It is fantastic news to find so many returning birds this early. At the end of the season I will be fitting geolocators to map migration routes, and it is very promising and somewhat of a relief to know that there is a high chance of recovering a good number next year. It is going to be fascinating to find out where they spend the summer and the routes they take.

One if the birds I saw this morning was Red-Yellow-Red, one of the first birds I caught in January. That was the last time I saw it, and despite searching the area throughout the following months I never re-sighted it. To see it back, not only alive and well but about 10 feet from where I caught it last year was reassuring but also mildly irritating. It was like spotting a truant school kid. Where did it go last winter, and if it did leave that territory after it was ringed, why did it come back to the very same spot? Perhaps it had a favourite perch hidden out of sight, or perhaps it was like another of last year’s birds that had a strange tendency to perch high in a tree (which is not what whinchats are meant to do!). I am happy to see it back none the less. 

7 birds have now been found, all returning to the same territories as last year

This morning I also saw a whinchat with just a metal ring but no colour rings. It was in a territory held by a colour-ringed bird last year, but I think it is unlikely that it had lost its colour rings. I use three colours for each bird and all of the returning birds have their full set. This spot is close to one of the CES sites (constant effort ringing), so I suspect that it was ringed there previously. I can’t wait to find out. One thing I have already learnt is that the red rings have bleached over the European summer and are now pink, which is (unfortunately) very close to the orange I also use. I’ll have to re-think my combinations from now on.


One of the returning whinchats from last year with colour rings (white and blue)

Today I was lucky enough to have a wonderful sighting of a cuckoo perched right in the open for quite some time. A great perk of fieldwork is that you get can’t help but see a great deal of other birds and wildlife. After comparing my notes with the bird book back at the car I believe it was a migrant Common cuckoo from Europe. These birds are very similar to the African species; however this bird had a bill that was black all the way to the head and barring on the breast was clean and sharp. It is a stunning bird. As much as I love tropical species, you don’t have to be bright and flashy to be a treat for the eyes.

My field assistant has just returned from a successful mission to get bait for the traps, so I will begin catching tomorrow. Today we found at least 8 un-ringed whinchats so we already have plenty to start with. Interestingly, these new birds were spread throughout the habitat and not just at the edges like the at flooded part of the site. This spot is dry, so perhaps whinchats do indeed need dry ground. Tomorrow I will start here. I usually catch between 3 and 5 whinchats on a good morning and I have lots to do to make sure everything is ready. Today I was pleased to find a driveable track leading right to the site which makes work so much easier. I wonder when that bird from today was first ringed? Hopefully I will find out tomorrow as that metal ring has guaranteed that I will be making a bee-line straight for that bird.

Tomorrow I’ll post more about how exactly one outsmarts a whinchat and what ringing them involves.

Emma

Tuesday, 25 September 2012

A warm welcome


I have just returned to APLORI after a long break in the UK and it’s good to be back. The change at APLORI is quite something – the dry and dusty place I left in April is now lush and green. The Bishop birds are in their glorious red plumage and other birds are busy hurrying about with nesting material, all to a backdrop of stunning butterflies and wild flowers. It is also cool and cloudy – perfect weather for fieldwork!

I headed out to the field this morning to see if I could find any whinchats. My site is now more akin to a marsh than a dry savannah full of thorns and I quickly gave up on keeping my feet dry. I soon saw a whinchat and checked it for rings, and astonishingly it was one of my birds from last year! What a treat. I could barely contain my excitement, much to the amusement of my field assistant. I still remember where each individual held a territory, and amazingly this bird had returned to the same territory it held last year. It’s incredible... to think that this tiny bird flew all the way to Europe to breed and then found its way to the same bush in the middle of Africa is just amazing. Through the course of the morning I found two more birds from last year, again in the same territories or closeby. One was perched on the very same bush were I caught it last season. It's still early days, so I am excited to find just how many of last year's birds return. I am quite proud of them.

There were also new birds about, but not too many. I suspect that it is still early. The majority of the site is still empty, and I noticed that the whinchats are sticking to the areas on the edges of farms, especially maize fields. I wonder why – perhaps these areas are better protected from predators, or offer better feeding prospects? The middle of the site is indeed quite flooded and thick with grass, whereas farmed fields have plenty of dry, open ground where whinchats normally feed. I suspect that it’s a combination of the two. It seems likely that the ‘better’ territories have been occupied first. This has indeed been found to be the case in other long distant migrants, such as American Redstarts. It will be interesting to see if these early birds shift territories throughout the winter as more individuals show up and more territories are occupied. What will happen when the habitat dries out, the ground becomes bare and the crops are harvested? The best way to tell will be to ring these early birds as soon as possible, and that is the plan for the coming weeks. I will also re-catch later-year’s birds, although if they can remember their way back to the same bush, I wonder if they will remember what a spring trap is? Let’s hope not, as re-trapping individuals between years is key to a large part of my research.

 Three birds so far (circled in red) have returned to the same territories this year

I also visited one of the two smaller sites yesterday evening, again finding a few new birds. It was late in the day and the sun was on its way down, so I am sure there are more. There is not a whiff of a whitethroat yet, however, so I’ll spend the rest of the week scouting out the other sites and then next week will see the first CES after the rainy season. I suspect it will be busy! I wonder what the other site is like now. The rains have made it hard to get about, so let’s hope it dries out soon.

I'll be posting over the next few weeks about what the migrants are up to and on what the first CES of the season brings.

Emma

You can read more about my research here