- What is wetland?
Wetland is an ecosystem that is inundated permanently or seasonally by water. We can differentiate wetlands with other landforms or other water bodies is by its characteristic of vegetation of aquatic plants, adapted to hydric soil. Wetlands have a role to some important functions, such as water purification, water storage, processing of carbon and nutrients, stabilization of shorelines, and support of plants and also animal, including birds.
- Waterbird or Waterland Bird
The bird who lives in a wetland area used to be called waterbirds. Waterbirds use many types of wetlands, such as swamps, lagoons, mudflats, estuaries, bays, and open beaches, freshwater and saltwater lakes, rivers, floodplain, and dams. The example of waterbirds including ducks, geese, swans, pelicans, grebes, ibises, spoonbills, herons, egrets, waterhens, rails, crakes, gulls, terns, and shorebirds. We can also categorize them into 3 main categories:
- Colonial nesting waterbirds: the type of waterbird who get together to breed and their breed depend on flood in the wetlands. You would find this type of colonial nesting bird include egrets, ibises, pelicans, herons, and cormorants.
- Non-colonial waterbirds: the type of waterbirds, including resident shorebird species, who don’t have to get together to breed just like colonial nesting type but still depend on wetlands ecosystem to nest and feed their young. They include waterfowl, grebes, crakes, rails, and waterhens.
- Migratory waterbirds: the type of waterbird, including migratory shorebird, who use the wetland site as a place to rest, feed, and breed only during their annual long journey, usually the migratory bird who live in wetlands in Australia (where most of the wetland has a dry season) but has to breed in the northern hemisphere.
- The importance of wetland
So, why wetland is so important to wetbirds? There are 3 main reasons why birds need wetlands: for feeding, breeding, and as a place to rest for a while during migrations.
So, what do we have in the dry phase? and how wetland birds Survive in the dry season?
You probably already understand about the avian or bird migration. The natural phenomenon when birds will seek another place to live or find a better site because the previous one is changing due to weathers or climates. Not every bird do the migration, so when the non-migration bird’s is facing extreme weather or unusual condition, their population might be devastated, for example, Wren bird, a non-migration bird who cannot stand on cold weather.
But luckily, some of the birds able to migrate even regularly, including wetland or waterbird. Birds who live in the type of wetland with a long period of the dry condition in the cycle will probably migrate to the other equally, semi-permanent, permanent, and coastal wetlands to stay in. They will move to a better site for feeding and breeding because just like we had talked earlier, waterbird needs the wetland for a place to eat, breed, rest, and also raise their young. If their resident is dry, they don’t really have much choice but to migrate or let say, to refuge in this case.
- Does global warming have an important role in the relationship between wetland and the bird?
Studies said that change in global temperature will result in the change of rainfall patterns, with some areas experiencing increases while others decrease. This can affect the period of time of wetland cycle. The waterbird who depend on their lives in might highly be stressed from habitat loss, not only from climate change but also from human activity which is agriculture. Not only by the irrigation system that might reduce the water flows of the wetland but also from the pollution and salinization.
The types of waterbird who live in the drier continent such as Australia, parts of Asia, or Africa need a long exceptional flooding event to breed but they are also known by their unpredictable and infrequent breeding. So the reduce rainfall which will increase the interval and duration of flooding event will only reduce their breeding success, which might lead to the devastation of population. Remember about Wren bird? They might not be able to survive in the cold weather, just like the waterbird without water, but Wren bird has high productivity so the number is able to recover after a few periods. This is not something that happens in waterbird. They already have an infrequent breeding period, so the habitat loss will only speed up their decline of the population.
Waterbird might be able to adapt to reduce the impact of the change in the condition or even migrate and leave their habitat to find a better one. But as a human-being who lives along in with one another, we have to realize our responsibility towards the extinction of animals due to habitat loss that is come from our activities such as non-environmental friendly agriculture and polluting their home.