Tagus Estuary Natural Reserve breed on adjacent farmland. Little bustard ("Tetrax tetrax") occurs all year but is more numerous in winter. Raptors which may be seen over the fields include black-winged kite ("Elanus caeruleus"), short-toed eagle ("Circaetus gallicus") and booted eagle ("Aquila pennatus") Nearby patches of woodland hold short-toed treecreeper ("Certhia brachydactyla"), European nightjar ("Caprimulgus europaeus"), red-necked nightjar ("Caprimulgus ruficollis"), Iberian magpie ("Cyanopica cooki") and many passerines. During the Spring and Autumn many species stopover on the Tagus during their migration these include curlew sandpiper ("Calidris ferruginea") in large numbers with many other shorebirds in smaller numbers, Common redshank and Balck-tailed Godwits reach their
Xylota tarda Xylota tarda Xylota tarda is a Palearctic species of hoverfly. External images For terms see Morphology of Diptera<br> Wing length 5·5-8·5 mm. Large red areas on black abdomen. Wing membrane not infuscated. Dorso-apical white bristle on metatarsus 1. Antero-dorsal pale hairs on the basal half of femur 3 uniform not longer than 1/4 the depth of femur. The male genitalia are figured by Hippa (1968). The larva is illustrated in colour by Rotheray (1994) ). See references for determination (but see Speight for contradiction) Palearctic Fennoscandia South to Spain. Northern Italy (Apennines) Slovenia. Ireland East through Central Europe into European