Inselaffe abroad

Wetland at Diadiam III...

...with the inevitable rubbish

As I mentioned in the previous post, it was instructive to be handling Palearctic migrants in their winter quarters - and to see just what sort of habitat 'our' birds use while we're shivering in the fog back at Lake C. The wetland area was obviously well-inhabited by waders, many of which pass through in varying numbers each spring and autumn here in S. Germany: Ruff, Wood Sandpiper, Greenshank, Little Stint, Curlew Sandpiper. There were also piles of Yellow Wagtails of varying flavour - flava, iberiae and flavissima for certain - other varieties may have been available. White Wagtails (maybe some of the Icelandic birds which pass through Slapton? Maybe Scandinavians?) weren't rare and we found a few Sedge, Reed and Grasshopper Warblers in the nets too.

Starter for 10: a Western Olivaceous Warbler. For a couple of weeks in January, I had my ear in to the song. Doubt that will last, sadly.

A nice male flava Yellow Wagtail.

This is the ecotone between wet Typha swamp and dry thorn scrub. A few metres of grazed grass, a handful of palms and a lot of Giant Milkweed... From the number of old thorn fences, the edge here is (was?) cultivated but there were no crops in there at present.

Typical thorn scrub around Diadiam III. Giant Milkweed, Mesquite and Simple-leaved Greenthorn

Slightly further from the influence of the wetland, the milkweed disappears and the ground cover becomes a sparse dead-grass layer with heavily-grazed thorn. Various Vachellia thorn species - all showing a clear browse line at cattle/donkey height cast surprisingly effective shade

This is where many passerines lurk. The difficulty is just finding them.

The thorn scrub was also used, but birds were way less abundant in general. There didn't appear to be all that many trees and shrubs in flower or fruit (though appearances were perhaps a little deceptive: certain trees were fruiting hard) and perhaps the general heat and dryness of the scrub meant that there just wasn't enough food around to support more insectivores. Familiar species like Common Redstart and Common Whitethroat were scattered around, and there were lots of Common Chiffchaffs - plenty of them already tuning up for the European spring. For me, there was a bit of spice in the presence of lots of Western Olivaceous and Subalpine Warblers (western - iberiae - were all we could identify with any degree of certainty) and a smattering of Western Bonelli's Warblers, along with the occasional Woodchat Shrike. The bulk birds in the scrub were, however, afrotropical residents. Lots of Mourning Collared Dove and Laughing Dove, and everywhere little groups of Namaqua Dove; small groups of Western Red-billed Hornbills; hordes of Sudan Golden Sparrows - and then in amongst them always some Red-billed Queleas, a scatter of Yellow-crowned Bishops, Black-headed and Little Weavers (and what appeared to be Vitelline Masked Weavers occasionally)... Look closely under the trees and you'll probably find the occasional Senegal Thick-knee or Long-tailed Nightjar snoozing away the heat of the day.

Namaqua Dove. A midget pigeon, with body size not much more than a sparrow

Long-tailed Nightjar pretending to be a branch on the ground

Common Bulbul trying to keep cool

Chestnut-bellied Starling being cool

Senegal Coucal - the epitome of cool.

A Grey-backed Camaroptera. The name is longer than the bird.

For a couple of nights at Diadiam III there was a tour group using the accommodation: they were well-equipped to see what additional wildlife they could lure in with a hefty UV light against a white sheet overnight. Some of the intrepid ringers weren't about to pass up the chance to nose around too, so had a good butchers' at the sheet in the early evening darkness. And there was plenty to admire, just not necessarily what was expected. Moths were sparse. A couple of Bedstraw and Striped Hawkmoths plus on Convolvulus Hawk were more or less the sum of the big-and-spectacular, and the small and less-spectacular were not much more diverse. But the beetles. Oh my... The second evening lamping brought the most astonishing numbers of water beetles and rove beetles to the sheet. There were so many on and around the sheet, that it became ever so slightly freaky to stand there with beetles crawling all over you. Between the beetles there were plenty of crickets, a few hefty cockroaches and the occasional damselfly. Not shabby.

Not - obviously - an invertebrate, but this cutie tried to share my room one night. Got quite pissy with me when I showed it the door.

Bedstraw Hawkmoth surrounded by rove beetles

House (?) cricket around the light

A rather fine ground beetle which is common in the area

Diadiam III was our base for the next three days. Ringing was quite varied - the nets set either around the edge of the wetland or in the dry acacia scrub just a few metres beyond. The ecotone between wetland and parched scrub was impressively abrupt: about 50 m of tough, well-grazed green grass between the inundated cattails and scrub with a ground flora parched dead for the season. It was instructive to catch some wintering Palearctic migrants (Wood Sandpipers in particular) and a few Cattle Egrets and Squacco Herons (first herons I've had the privilege to handle) and to start looking at the local birds in more detail: Spur-winged Plover, Long-tailed Nightjar and plenty of Black-headed Weavers.

Cattle Egret being well-behaved

Cattle Egret still being well-behaved

Squacco Heron. Also being well-behaved. Interesting to discover that they have very very finely-serrated bill edges. Makes sense, if you need to cop hold of slippery fish, but they're a devil for tangling in a net.

When the day grew too hot - usually about midday - or windy, there was time to explore a little. Walking the edge of the wetland was moderately productive for odonata, though there wasn't the diversity I'd hoped for. The commonest species by far were Broad Scarlet Crocothemis erythraea and Black Percher Diplacodes lefebvrii, but patience paid off with a few Long Skimmer Orthetrum trinacria and one or two Pied-Spot Hemistigma bipunctata. There were plenty of (African) Common Bluetails Ischnura senegalensis to see too, though picking up any other damselflies was decidedly hard work.

Common Bluetail - Ischnura senegalensis rather than the European elegans. The black pattern on S2 is quite a difference.

I think this is a female Pied-Spot Hemistigma albipunctum

The well-named Black Percher Diplacodes lefebvrii. Perching.

The thorn scrub was also pretty well dominated by giant milkweed plants - a toxic ruderal which seems to coppice well when it's cut. Apparently the latex is impossible to remove with soap and water, so you have to wait for it to dry and then peel or chip it off. Some of the plants were pretty large around the base, so they can obviously get pretty old. They had an interesting fauna attached - a grasshopper species (Poekilocerus sp?) and plain tiger butterflies - their respective nymphs and larvae munching away and, given their warning colours, merrily absorbing the toxins. There were also tephritid fruit flies busy using the fruits and a bright orange aphid (oleander aphid?) sucking on the sap. These in turn were being munched by ladybirds and tended by ants, which themselves were being taken out by some very juvenile mantis (possibly Sphodromantis viridis, but as Mantis religiosa and a Miomantis species were also in action, who knows...)

Grasshopper nymphs on giant milkweed. The flowers seem to be particularly favoured.

Plain tiger caterpillar - this one's not on milkweed for once

Oleander aphids?

On the second morning four of us elected to go on a boat trip to see the pelicans - for which Djoudj is famous - on the Djoudj river. We were driven out to the embarkation point and had a while to wait until our boat set off, so enjoyed a bit of roadside birding. There was a group of White Pelican fishing at the sluice under the road and constant groups of pelicans passing overhead in the direction of the colony. Once we were past the initial 'wow' factor of the pelicans, there were other things to take in: an Osprey perched up on a pylon; Reed Cormorants and White-breasted Cormorants accompanying the pelicans; Squacco Herons lurking on the edge of the vegetation trying not to be seen; a couple of Little Bee-eaters on some cattails. A warthog sauntered out of the scrub and trotted down the road. A Jacana feeding in the lee of some cattails. That kind of thing.

Great White Pelicans doing their thing in the early morning sunshine.

White-breasted Cormorant - variously treated as a species in its own right and a subspecies of Great Cormorant - on the way to hanging with pelicans

Little Bee-eater on reed

Squacco heron landing...

...and landed. Trying to merge with the primrose-willows and cattails.

Warthog. Trotting.

Soon enough we were gathered up for the boat, joining another small group of tourists. We puttered off up the river and were soon passing some more waterbirds: African Darters (always elegantly cool), an African Fish-Eagle posing on top of a dead tree - against the light, naturally - and trying to ignore us. The boat was soon being followed by marsh terns, all apparently Whiskered Tern, picking small fish and invertebrates out of our wake. Then we rounded a corner and were faced with a chaotic feeding frenzy of pelicans, egrets and cormorants through which we had to gently nudge our way. That was... pretty impressive! Pelicans upending and diving right next to the boat, almost an arms-length away from us, cormorants twisting and sliding through between them, terns hanging above and waiting for an opening to drop in and snatch a snack, and all along the edge of the river egrets and herons (five species present and correct) leaning eagerly forward to grab their share of any fish that escaped towards the apparent safety of the reeds.

The elegant African Darter (a.k.a. snakebird in a number of languages)

Feeding frenzy!

More feeding frenzy.

Skimming the surface. They fly so close, it seems incredible that they don't clip it. Maybe the youngsters get soggy while they learn...

Whiskered Tern preparing to dive.

Whiskered Tern on the dive

Black Herons - the ones famous for fishing under an umbrella formed by their own wings - on their way to the feeding frenzy

Not just Whiskered Terns either - a couple of Caspians joined the fun round the boat

The Yellow-billed Stork that nearly escaped the picture

After all that, the sight of the pelican breeding island was somehow pretty tame. The island is built up to keep the colony safe from flooding, and there was standing room only with a mass of nearly full-grown pelican chicks. The occasional Sacred Ibis stalked quietly along the edge of the colony - presumably foraging - and there was a constant coming and going of adult pelicans, but it all seemed a little uneventful after the earlier encounter. We rounded another vegetated island to head back down the river, admiring a basking west African crocodile, and then bumped into a quartet of Blue-cheeked Bee-eaters busily hunting dragonflies.

It's a bee-eater. With blue cheeks. Guess what it's called...

Pelican predator. Good disincentive for swimmers.

Marsh Harriers were cruising over the reeds everywhere we looked

Between Diadiam III and the entrance to Djoudj there is a sizeable shallow wetland, with variously reeds and grassy edges, small islands and mudbanks. Perfect, in fact, for waterbirds. While we were there, a daily flock of White-faced Whistling Ducks built up from a few hundred to a few thousand, chilling on the water and the islands. Every time a predator hove into view - even as minor as a Marsh Harrier - they spooked and swirled into the air, squeaking frantically. The next most abundant species on the wetland were Shoveler and Black-winged Stilt, then a nicely mixed bag of other waders and herons. Lots of Little Stint and Wood Sandpipers, a regular group of Black-tailed Godwits (one sporting colour-rings), Ruff, Ringed Plover, Kittlitz's Plover, Marsh Sandpiper, Redshank, Greenshank... etc. etc. Backdrop to these was a smattering of Spoonbills, Sacred Ibis, and both Greater and Lesser Flamingos.