When is it best to come ?
The answer is : It depends on what you wish to see
If you want to see thousands of Common Cranes leaving the lake in the morning or coming back in the evening, any time between the end of October and the beginning of February should give you this opportunity. We had an incredible record of just over 205,000 cranes on November 11th 2014 (see an article about it in HBW Alive).
If you are interested in Wildfowl, about 20 species of Ducks, Geese and Swans can be seen from November to February, among which the following species: Whooper and Bewick’s Swans, Greater White-fronted Goose and Bean Goose, Goosander, Smew, Goldeneye, Eurasian Wigeon, Eurasian Pintail, Red-crested Pochard (this species also breeds near the lake)…and many of these birds are still present in March and April.
If you prefer raptors, the White-tailed Sea-eagle is normally present from November to early February but very unpredictable and you will need some luck to see it. The Red Kite no longer breeds here or very rarely but can be seen on migration from February to April and in autumn. The Black Kite is present from March to July and you will have to wait until April to see The Marsh Harrier which is an uncommon breeder. The Montagu’s Harrier can be looked for on a special half day or day trip some 50 km away from the lake in May and June. The Osprey is not uncommon in March-April and in August-September.
The best time for Herons is from the end of April to the end of August with up to 8 species nesting around the lake : Grey, Purple, Black-crowned Night and Squacco (very rare) Herons, Great, Little and Cattle Egret and Little Bittern (rare). The Eurasian Bittern can be looked for on a special day out to Argonne (same conditions as for a trip to Lorraine).
A few pairs of Mediterranean Gulls nest among a Black-headed Gulls colony near the lake and a Common Tern colony is established on nesting platforms on the lake
You should not miss the breeding pair of White Storks nesting in a village near the lake and, if you want to see the Black Stork, the best time is the end of August and the beginning of September.
The best time for waders is when the level of the lake is going down from mid-August to October.
If you like Woodpeckers, Black, Green , Lesser Spotted, Medium Spotted, Great Spotted are present throughout the year but easier to see in spring whereas the uncommon Wryneck arrives in April and is easier to locate when singing.
The Hoopoe is present in at least one village near the lake, mainly from Mid April to August and lots of songbirds can be heard, and seen from the end of April, among which The Common Nightingale, the Common and Black Redstarts, the Serin, the Melodious, Sedge, Reed, Great Reed, Grasshopper, Garden and Wood Warblers, the Lesser and Greater Whitethroats, The Spotted Flycatcher, The Golden Oriole and even the Bluethroat. The Red-backed Shrike, the Tree Sparrow, The Linnnet, the Corn Bunting and many other species can be looked for around the lake.
It is also possible to organize one-day trips to look for rarer birds such as the Hen Harrier, The Eurasian Stone Curlew, the Eurasian Bee-eater , the only regular French nesting pair of Red-necked Grebes, the Grey-faced Woodpecker, the Stock Dove, the Marsh Warbler, the Tree Lark, the Crested Lark…
Of course, many other species are present and you can expect to see between 60 and 80 species of birds in a single day, if the weather is fine indeed.