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A few days after the snow has melted, mid-May or perhaps slightly later, the peatbogs and aapa mires of northern Finland are alive with recently-arrived Wood Sandpipers. The minerotrophic aapa mires, swamps that catch nutrients from the surrounding land via run-off, stretch from northern Finland well into Siberia. The formation of these mires started some 9000 years ago, at the end of the last ice age. At an average peat accumulation of less than 0.6 mm annually, aapa mires gradually convert into raised bogs, a process that is usually slowed by large-scale fl ooding in spring. Mammals, including man, fi nd traversing broad aapa mires extremely diffi cult, because of fl ark-fen pools. In such relatively safe havens Lapland’s Wood Sandpiper reached densities of up to 13-18 pairs per km2 in the 1800s and early 1900s, but present-day fi gures indicate a decline, possibly associated with fen drainage. Between the breeding and wintering grounds, some 7000 km apart, drainage is also diminishing many of the European staging areas on which Wood Sandpipers depend; here they accumulate the fat reserves necessary to cross both the Mediterranean and the Sahara successfully. As with so many migratory species, life is becoming increasingly complicated.

344 Living on the edge Breeding range Azov-Black Sea area. Birds ringed in the Ukraine have been recorded in Chad and Nigeria, where they overlap with the wintering range of birds The monotypic Wood Sandpiper breeds across northern Eurasia from NW Europe (Lebedeva et al. 1985, Nankinov 1998, Diadicheva & from western Fennoscandia, the Baltic States and northern Ukraine Matsievskaya 2000). The Wood Sandpipers from Russia and western through European Russia and Siberia east to Anadyrland, Kamchat- Siberia migrate mostly to eastern and southern Africa (Lebedeva et al. ka and the northern Kuriles, and south from the southern edge of 1985, Vandewalle 1988, Oschadleus 2002, Stroud et al. 2004). the tundra to the southern Urals, Kirgiz Steppes, Russian Altai, Homeward migration speed in most regions is higher than on out- northern Mongolia and the Amur River. ward migration and has shorter stopovers. The low body masses The northwest European population is estimated at 285 000- measured in birds reaching southern Europe and the Middle East 407 000 pairs, mostly in Finland, representing an estimated 0.86- (Akriotis 1991, Yosef et al. 2002) are rectified quickly through frantic 1.22 million birds. Applying Finnish densities to European Russia feeding during stopovers; weights gradually increase during north- would produce another 0.6-0.9 million pairs (Stroud et al. 2004). ward migration. In southern Sweden, birds had reached a mean body Numbers breeding in western Siberia are unknown but presumably mass of 71 g (range 56-86 g, n=43; Persson 1998); mean masses of 67- very large, for it is the most abundant wader in the forest-tundra (Ro- 70 g in North and NE Poland also attest to birds fattening well (Rem- gacheva 1992); this population is estimated at >2 million birds isiewicz & Wennerberg 2006). Even when in a hurry, Wood Sandpipers (Stroud et al. 2004). evidently are able to accumulate fat reserves along the way (Remisie- wicz et al. 2007, Muraoka et al. 2009).

Migration Distribution in Africa Wood Sandpiper is entirely migratory and winters in Africa south of the Sahara. Breeding birds from the northern and central Palearc- Wood Sandpipers are widespread throughout West Africa in winter, tic, west of 40˚E, winter largely in sub-Saharan West Africa. The NW occurring wherever shallow fresh, brackish, or even salt water is European birds follow a south-southwesterly course through Eu- present for some time, but rarely assemble in large concentrations. rope (Fig. 203). Extensive ringing has shown that in late summer Wood Sandpiper migrates southwards initially in short hops, staging at foraging sites for only a few days and at first carrying low fat loads. The observant prose stylist Sergei Timofeevich Aksakov, also hunter extraordinaire in the Orenburg region, in 1852 had even then recorded in his Notes of a provincial wildfowler, that “fifi”, a local onomatopoeic name for Wood Sandpiper, “are never fat. They de- part so early that they have no time to put on weight”. Adults migrate ahead of juveniles, and on average carry higher fat loads. The short-hop migration strategy calls for longer stopovers in southern Europe in order to accumulate sufficient energy reserves for the non-stop flight across the Mediterranean and the Sahara (Scebba & Moschetti 1996, Wichmann et al. 2004). One such site is the Ca- margue, where large numbers of Wood Sandpipers are known to assemble in autumn (Hoffmann 1957). At some sites in northern and central Europe, Wood Sandpipers accumulate sufficiently high energy reserves to cover longer distances, such as from southern Sweden (Persson 1998), Jeziorsko in western Poland (Włodarczyk et al. 2007) and Münster in western Germany (at a sewage farm; Anthes et al. 2002). Other individuals use a scattering of refuelling sites throughout Europe, putting on weight en route (Leuzinger & Jenni 1993, Meissner 1997). Birds with adequate fat reserves may fly uninterruptedly to stopovers in southern Europe, notably the Rhône delta, where energy reserves can be replenished. One Münster-ringed bird was shot the next day at Bouches-du-Rhône (1000 km; Anthes et al. 2002). Many Fennoscandian birds take a more southeasterly course via the Balkan Fig. 203 European ringing locations of 69 Wood Sandpipers recovered countries, or through the Ukraine (Sivash as a stopover) and across the or captured in West Africa. From: euring.

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