![]() Young geese learn the migration route and landmarks by following their parents and other experienced geese. Geese have a physical compass in their head that allows them to tell north and south by detecting the Earth’s magnetic field. They may also use celestial cues such as the sun and stars. Geese navigate based on experience, using landmarks including rivers, coastlines and mountain ranges. Geese fly by day or night, depending on factors like weather conditions or brightness of the moon. Single families of geese, or flocks of several families together, take off and head south. Maybe you’ve observed flock members signaling they’re ready to go: They honk loudly and point their bills toward the sky. Once conditions become so tough that they can’t find enough to eat, geese migrate. They usually remain in their summer range until the weather is cold, water starts to freeze, and food gets hard to come by. They migrate continuously, except for short stopovers to fuel up on insects, fruit, or seeds before continuing on their way.Ĭanada geese and other migratory geese species are different. Most migrate at night, individually rather than in flocks, and they know where to go and how to get there without guidance from parents or other birds. These birds, such as swallows, orioles and warblers, leave their northern breeding place before weather turns harsh and food becomes scarce. For most bird species that migrate from temperate climates to the tropics in winter, migration is instinctual. There are two different types of bird migration. Jennifer Yakey-Ault/iStock via Getty Images When it’s time to go As floodwaters recede, invertebrates are pushed towards the surface if the water table remains high (within 20cm of the surface), providing prey for waders.Geese fattening up by eating some underwater foods. In the winter, extensive but shallow (less than 50cm) flooding can bring huge numbers of wildfowl to some sites, especially where varied conditions provide opportunities for diving, dabbling and grazing species. Most grazing marshes are used for pasturing cattle some are cut for hay or silage. A bye-product of fenland drainage, washlands were used for flood water storage. In East Anglia in particular, grazing marshes resulted from the creation of ‘washlands’. Floodplain grazing marsh has similarly generally been embanked, drained and agriculturally improved, however, in some cases, grazing marshes were created on better drained floodplains through the use of sluices and ditches, plenty of grass and field boundaries for grazing livestock. Coastal grazing marsh was generally ‘reclaimed’ from salt marsh through embankment and drainage, a process that started in the medieval period – the lines of old saltmarsh creeks are still sometimes evident. Tussocky (areas where grass is longer and thicker) and damp swards provide good habitat for foraging and breeding waders, and shallow flooding creates ideal conditions for wildfowl during the winter.Ĭoastal and floodplain grazing marsh is defined by proximity to water, topography and management rather than the underlying substrate or the vegetation. However, freshwater or brackish ditches (created for drainage purposes) and the remains of old creek systems where farmed land has been created on former saltmarsh can support interesting plants and good populations of invertebrates, including those such as dragonflies and damselflies that have both aquatic and terrestrial stages. Perennial rye-grass, Yorkshire fog and rushes tend to dominate the sward, enlivened by damper patches of floating sweet-grass, creeping bent and silverweed. Some 500 plants have been recorded from the most diverse grazing marshes, but these comprise just 5% of grazing marshes - most have been agriculturally ‘improved’ and are of limited botanical interest. ![]() ![]() Coastal and floodplain grazing marsh is found on low-lying coasts and along slow-flowing rivers and estuaries.
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