I spent a couple weeks in sicily last september/october, while working most of the trip I still managed to get 107 species on my list! I was based originally near Catania but travelled a little bit once I'd finished my job. I'll list a few star locations here:
Etna- fantastic for raptors, with Booted Eagle on the lower slopes, and plenty Golden and a Bonellis at higher latitudes. Also loads of Rock Bunting and Wheatear near the Lava field, a sight to behold in itself!
Saline di Priolo Gargolo- an absolute must, fantastic for Greater Flamingo, Black Winged Stilt, Ferruginous Duck, Slender Billed Gull, and other southern Europe specialities. Waders I suspect will be beginning to swell in number in August but not yet at peak. I was lucky enough to see my first Marsh Sandpiper here, but also Kentish Plover and Little Stint were numerous. Also large groups of Spoonbill and a Whiskered Tern was an excellent surprise! Only negative is the site seems dilapidated and abandoned, I have no idea if it ever opens but it certainly wasn't when I was there. I observed everything I saw there from outside the fence looking in! Don't let it being closed stop you, you can see so much if you persevere and find a good vantage point.
Penisola Magnisi- right by Priolo Gargolo, this little peninsula appears to act as a migratory bottleneck, with several rare passage species showing up during my visit, including Richards Pipit, Red Throated Pipit, and Western Black Eared Wheater! Also a great site to see Stone Curlew!
Capo Murro Di Porco- another migratory hotspot that gave me a chance to see a juv Woodchat Shrike, while past records included Rufous Tailed Scrub Robin. Scopoli's Shearwater are reported often close in from the lighthouse, I wasn't so lucky but the cliff roosting Peregrines were a treat! Another good site for Stone Curlew.
Oasi del Simeto- I went here to look for il Pollo Sultanto (Western Swamphen) but was sadly eluded, although many others have located them there. I was however happy with far better views of Ferruginous Duck than at Priolo Gargolo, and also a group of wintering Black Necked Grebes.
In rural areas you'll see Hoopoe, Turtle Dove, Spotless Starling, and basically anywhere within a couple miles of the sea on the east side can produce migrants such as passage Black Kites that were still moving in decent numbers later in the year, I imagine you'll get a better diversity of migratory raptors in august. I also had one Short Eared Owl in similar circumstances, while Scops, Little, and Tawny are all resident and abundant. Check the coast for Blue Rock Thrush too, but you can even see them on top of houses and in gardens! I never saw the mythical Sicilian subspecies of Long Tailed Tit, from what I heard it is quite reclusive and restricted. Lanner Falcon was also missed, I couldn't find hardly any info at all on potential hotspots for it. Hope this helps.
PS, final bit of advice, if you can, check out Palermo, it's a great city, and the nearby Punto Capo Gallo is home to a wonderful secret should you wish to make the walk to the top. All the best!
