The first part of our “roving” actually consisted of staying in Ouaga, seeking any other patches in the wider area that might support wood warblers. The best looking sites from the available satellite images were the wooded valleys in the Gonsee Forest Reserve to the east of the capital, with the wooded savannahs in between appearing rather sparsely forested and, at the time of the picture being taken, burnt. Two mornings here were quite a surprise, with several wood warblers appearing after mp3 playback even in the scrubbed over wooded savannah, and 8 in one spot nearer to a wooded valley, and also one in very marginal land fringing a large maize crop. The other sites selected from the aerial shots appeared to the un-trained eye to be stands of trees that may not have been “forest” as such, and indeed they weren’t. Nevertheless, a Eucalyptus plantation was still worth surveying, as the tagged birds in the monastery were not averse to using small Eucalyptus trees in otherwise quite open areas. In the end no birds were sighted here, and nor were they found in 2 other ”forest” patches which were in fact largely scrub, Eucalyptus and mango. I believe negative data is just as good as positive for the presence/absence model!
Onwards then to sites further afield, as we spend a last week in Burkina before heading back through Ghana to get to Pepease by Nov 15th.
19th – 28th Oct Final week of tracking
The tracking team continued with the regular check-ups on the whereabouts of the tagged birds in the Monastery. Some interesting patterns are again emerging, just like on the study site in Ghana, and we’re gaining an interesting early picture of the home ranges of the birds in this area, along with some measure of how long they spend here. The final tagged bird was still emitting a signal on the 27th, but with only a projected 2 or 3 days left to run, we decided that a team of 4 would be better occupied surveying new areas for wood warbler presence. Over the next few days we will explore any areas that look suitable (or even wooded/partially-wooded areas that don’t look suitable!) to see if there are any birds around.
In other news for the period, Aly returned from Tanzania with a view to returning to Oursi with a soon-to-arrive mini-freezer. Said freezer took another 2 days to land in the country and we had to wrest it from customs so that Aly could speed his way north in time for the Tabaski festival. I’m pleased to report he made it! He has subsequently said that the freezer works brilliantly, powered by the battery that’s charged by the newly installed solar panels. They’re all set to go with the dove Trichomonas parasite sampling.
Another visit to the forest park in Ouaga on the 25th yielded some quite extraordinary figures. With 52 wood warblers seen last week, a different, wetter section held 79 birds, with a group of 20+ in just one spot. Truly remarkable!
Thursday 18th Oct. City park visit
We take a long-planned break from tracking this morning. Aware from previous experience that disturbance can be a bit of an issue on Thursdays with noisy children around the ringing site, we leave for Ouaga forest park early to check on presence of wood warblers there.
After a quiet start, with a flock of lesser blue-eared starlings overhead and later foraging for berries in some low shrubs, we hear a first nightingale, soon followed by another, and then a couple of melodious warblers. A willow warbler is seen, but for a while no wood warblers respond to the mp3 playback. Things pick up a little as the sun rises and mixed Estrilda finches flit around low on and near the path. At about 0630, we hear our fist wood warbler call.
A stroll around a fair section of the park over the next 3 hours yields an amazing 54 wood warblers, including at one spot over 15 birds – we actually lost count as they kept arriving in response to the playback! To me this is a truly amazing tally, especially when one considers the total lack of records from Burkina in our first year of surveys – the park was clearly the place to be back then, if perhaps only during October! It seems hard to believe these birds will remain here once the site begins to dry out, and one would expect them to head south to more-humid zones as the days pass.
After a quick shop for breakfast things and a visit to the office, we head back to attempt tracking again after the difficulties of last night. We have absolutely no problem whatsoever! All 3 birds are easily located, so our worries about a hastened departure are assuaged for now.
We’re invited to dinner with Henri this evening. A very un-African sausage and mash!
Wednesday 17th Oct. Decoy wood warbler works wonders!
Following last night’s rather stormy weather, we manage to find the tagged birds quite easily; bird “10” is in a surprisingly low bush, happily preening away, and the other two are also quickly located. We wonder whether the lost tag from the 14th/15th may have made its way down from its suspected lodgings in that tree. Using the radio receiver, it is very quickly pin-pointed on the ground – once again still attached to a pair of moulted tail feathers. It does seem odd that these birds should drop their feathers quite so readily. The Ghana birds, which didn’t arrive on site until well after mid-November last year, retained their tags until we left the site on the 13th of December, which was actually just after the start of moult witnessed in other birds in the area.
Our trapping effort with the mp3 playback is yielding very little, so we decide to try our wood warbler decoy one more time. Oppong deftly straps it to a “branch” of a small “tree” (a fallen piece of brushwood) and then sticks this vertically in the ground right next to the net with the mp3 song playing. Not really expecting much, after all the song alone is not working and the decoy has not appeared to work before, we are therefore surprised when 20 minutes alter Japheth returns from a net round with 3 wood warblers. I’m not even sure I’ve seen 3 wood warblers in a net before – in fact, definitely not! We colour-ring and fully process these birds, but we won’t be tagging any more birds for now. We need to move on to other potential wood warbler sites in southern Burkina within the next week. Ideally we’d like to get some gauge of the importance of the region as a staging post before the birds head further south to the more humid forest zones, in Ghana and beyond.
This evening Roger and Japheth report that one bird has apparently completely disappeared, and the other 2 are getting tricky to find! Well, this rather brings our potential departure date forward! The “vanished” bird’s tag was due to last well into next week. If this is the case, then more exploration for potential wood warbler sites will begin over the weekend – but where should we go? Time to consult some satellite images, and our colleagues at Naturama!
Tuesday 16th Oct. A storm strikes
A poor morning of ringing, with only 3 birds caught, and no migrants.
Oppong and I head into town this afternoon for a few sundry items, including a dongle to attempt to get some sort of internet connection. Whilst in the city centre, we notice several market stall holders packing things away somewhat early, and looking skywards. Is the rain coming, I ask? No, the wind, they reply. Sure enough, some seconds later the wind picks up and the visibility drops, as a dust storm hits the city. With our chores done, Oppong drives us back out of town, struggling to manage the steering at times with the strong gusts swirling around. Folk on bicycles with large loads are having the worst of it. We make it back to let Japheth and Roger go tracking, but then as darkness falls and they return – having got a soaking in the field – so the heavens open over Koubri. The high winds and heavy rain are short lived, but enough to cause concern over the survival chances of the tagged birds overnight.
Oppong rustles up another fine batch of red-red, this time at a reduced cost, seeing as we did get the beans and plantain ourselves! After those rains though, the temperature has plummeted at Denise’s cafe, and for once, I wish I were wearing another layer – most unusual for this time of year.
Monday 15th Oct. One tag found, another up a tree?
This morning at the monastery we find a third bird has indeed shed its tag by moulting its tail. It happens to be the one of last Thursday’s birds, and the same tag that was dropped after just one day by the bird caught on the 7th. We also confirm that, after Roger and Japheth’s suspicions yesterday, a fourth tag has fallen, but for some reason we cannot find it. We were not expecting to find the other dropped tags quite so easily, but seeing as we did, here we begin to think that something is up – and indeed, it is. It appears to be stuck up a tree! A good shake of those branches that we can reach changes nothing, so for the time being we concede defeat.
Quite by fortune whilst tracking one bird later in the morning, I spot the colour rings of another, and it’s the bird that has shed the tag in the tree, so at least we know it’s still around.
As a solution to our culinary woes, Oppong takes over at his new friend Denise’s Koubri services to rustle up some fried yam, chicken and his tomato salsa. Very much appreciated, although it appears that we end up paying twice – once for the ingredients, and then again for the finished meal. We can’t have that happening too often!
Sunday 14th Oct. More radio-tag issues...
Up and out without any hesitation this morning! Pack my bags and leave the cell that was my room last night, and we’re off into the field by 0500.
Having set a net with a mixed warbler tape playing, the first bird caught (before I’ve even had time to finish opening the net) is a pearl-spotted owlet, right above the mp3 player! What a cracking bird.
Later we manage just the one migrant, a most welcome first willow warbler of the season.
An extraordinary spectacle during the course of the morning was the procession of people on foot, on bicycles and on motos, heading for the monastery. A very grand service was clearly about to take place. After about 2 hours of worship, several of the congregation came to watch our work, or so it appeared, but then we soon realised that we were being ousted from our ringing shelter – another round of songs of praise was about to take place here too! Not wanting to get in the way, we quickly wrapped up the mornings affairs and left the choir behind.
The evening’s tracking session indicates that there may be a problem with one or two of the 4 tagged birds. One is static near a shea tree, on two consecutive search attempts, the other is proving difficult to find on the second effort. We’ll have to have a good scour for any dropped tags tomorrow.
The evening’s meal is at a maquis nearer the lake in Koubri, the same place as one of the accommodation options yesterday. Despite being quite busy, and with perhaps more atmosphere than the Koubri services, the food is disappointingly poor. We must seek out some alternatives!
Glad to settle in to the nicer rooms back at Henri’s place tonight. Much more comfortable!
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