The annual avian exodus from Equatorial Africa - for pastures old - has ended. By this day; which back home at Leighton Moss RSPB reserve in Lancashire, Northern England, at approximately 54 degrees North; was always my most eagerly anticipated date on the bird-watcher´s calendar; that is, by May 15 a certain quietude has settled over these green hills of Africa.
My last upwardly mobile Palearctic bird was at Hippo pools in Lake Manyara National Park; on Wednesday May 9 when an adult Little Stint in burnished rufous-chestnut breeding plumage (bound for Arctic Russia) foraged so daintily between the toes, well almost, of comparatively ungainly and undoubtedly ancient Spur-winged Geese, five gorgeous parasol-fishing Black Egrets, several snail-stalking Glossy Ibis and two very crisply marked Blacksmith Lapwings. Whilst overhead non-breeding Whiskered Terns and Collared Pratincoles, Plain (Brown-throated) Sand Martins and rippling Madagascar Bee-eaters swept back and fore over our heads. All of us were almost oblivious, it seemed, to eighteen rough, frequently squabbling, always blundering brown Hippos who were churning the lakeshore waters only fifty metres farther and in so doing energising (i.e. institutionally strengthening) this particularly productive branch of the Rift Valley food web.
On Monday May 7 I had metaphorically kissed goodbye to the last Russian (or Central Asian) Barn Swallows who were threading between pewter pot thunderheads massing over neighbouring Tarangire National Park. We passed in opposite directions without acknowledgemnet, like those old ships of the night, they were lacing nor’nor’ east through welcome low-flying insect masses, travelling at over 600 kilometres per day, whilst we were heading for the flooded Acacia nilotica woodland at the western edge of the national park in Lake Burungi only ten kilometres distant. Lake Burungi, like Manyara, is a largely alkaline, seasonally fluctuating, lake in the northern Rift Valley. And incidentally it was the first really exciting place that I went a serious birding here in Tanzania. That day (January 9, 2005), a dose of tropical sunstroke apart, was particularly memorable for the many Royal Tiger-beetles, racing on stilt-like legs, on the geometrically patterned crusts of mud that bordered a narrow spring-line feeding freshwater to the lake from the west. These fearsome predators are wonderful beasts (certainly they should be in “the safari small five”) an exquisite and lethal adversary – definitely the fighting match of any other arthropod - in their shining toffee-coloured armour, four times the size of the familiar Green Tiger Beetle of this observer´s European homeland. That period, from Yule 2004 onwards, was a dry time indeed, and a lesson in belt-tightening for all of us, as a dust-inducing drought blanketed much of sub-Saharan Africa.
Thirty months later, all has changed, as the nights of the long rains continue. A stab in the back perhaps for many of those cleverly costructed models that predict long term desiccation of the African savannas. The seldom reported El Niño of 2006, well is it continuing? April of this year, traditionally four weeks at the deepest trough of East Africa’s “Long Rains”, was not particularly wet; we’ve had much wetter months in this past dry season. However nowadays as we slide into mid-May, and the nights get steadily longer and creepingly cooler, the intensity of the rains appears if anything to be strengthening and not weakening.
In 2006 there was exceptionally heavy snowfall on Kilimanjaro in line with above average rainfall across East Africa. The summit glaciers actually became bigger, probably for the first time in over ten years, temporarily halting their long term retreat. Unfortunately even this exceptional snowfall cannot make up for the huge losses that have been incurred, probably over the past century and a half at least. Climate modelling of the large-scale seasonal atmospheric circulations over the Indian Ocean have shown that there has been a trend to drier years during this same period.
Last weekend our family went camping deep in the Maasai plateau, slightly higher even than Arusha, and part of the so-called Maasai steppe of central Tanzania. Instead of the two cool dry nights that we anticipated we experienced one clear warm one, when the Southern Cross blazed down upon half of this sleeping continent cloaked in inky darkness, and one cold, drizzly one.
Next morning the “resident” birds; many already in partial moult, and in many cases continuing to attend recently fledged young; seemingly couldn’t fathom which way to turn; as new grasses sprouted and the invertebrate masses rose again, reinvigorated by yet another drenching. Two Flappet Larks (Mirafra rufocinnamomea), arguably of the very 'warm form' torrida, rose from the tops of their shrubby acacias and circled in the greyness, “prrrrrrr-rrrp”, vibrating their rounded rufous wings in that inimitable way. Seemingly emboldened by the cloying mist and murk, perhaps they were contemplating a “second brood”. I can’t say that I felt the same way.