to their native South American range. They eventually crossed the Wakenitz river and settled in Nordwestmecklenburg in the area around and particularly to the north of Thandorf village. A biosurvey conducted in late 2012 found the population had grown to more than 100 and was settling in permanently. In early 2017 the population reached about 220 birds. As local farmers suffered harvest losses due to the birds, some farmers were granted an allowance to destroy the eggs of the birds to stop the population from growing further. At the end of 2017 a population of about 250 birds was estimated. They are regarded as "domestic" and thus protected from hunting. In the autumn of 2018, the German population grew to 566 individuals, and hunting of the birds was allowed; additionally, the population was reduced by destroying eggs during breeding season. Behavior and ecology Individual and flock behavior The greater rhea is a silent bird except during mating season, when they make low booming noises, and as chicks, when they give a mournful whistle. During the non-breeding season they will form flocks of between 10 and 100 birds. When in flocks, they tend to be less vigilant, but the males can get aggressive towards other males. When chased they will flee in a zigzag pattern, alternately raising one wing then the other. These flocks break up in the winter in time for breeding season. Feeding and diet The rhea's diet mainly consists of broad-leaved foliage, particularly seed and fruit when in season, but also insects, scorpions, fish, small rodents, reptiles, and small birds. Favorite food plants include native and introduced species from all sorts of dicot families, such as Amaranthaceae, Asteraceae, Bignoniaceae, Brassicaceae, Fabaceae, Lamiaceae, Myrtaceae or Solanaceae. Magnoliidae fruit, for example of Duguetia furfuracea (Annonaceae) or avocados (Persea americana, Lauraceae) can be seasonally important. They do not usually eat cereal grains, or monocots in general. However, the leaves of particular grass species like Brachiaria brizantha can be eaten in large quantities, and broad-leaved plants (e.g. the sarsaparilla Smilax brasiliensis) have also been recorded as foodplants. Even tough and spiny vegetable matter like tubers or thistles is eaten with relish. Like many birds which feed on tough plant matter, the greater rhea swallows pebbles which help grind down the food for easy digestion. It is much attracted to sparkling objects and sometimes accidentally swallows metallic or glossy objects. Rheas are also