The Convention on Wetlands of International Importance was adopted in Ramsar, Iran, 46 years ago, on 2 February 1971. That date is now celebrated globally as World Wetlands Day. The importance of wetlands was again declared by the United Nations on World Water Day (22 March 2018), with the following statement:
"How can we reduce floods, droughts and water pollution? By using the solutions we already find in nature. The answer is nature!"
Wetlands occur in different environments around the world, and they all have divergent characteristics. However, they do all have one thing in common: they are extremely important habitats of rich biodiversity, and they have an important role to play in the lives of humans and animals alike.
Whether it is called a marsh, swamp, vlei, bog, seep, fen or pan, a wetland is a unique ecosystem – an area of land saturated with water, either permanently or seasonally. It is usually home to many species of plants and animals.
Sadly, 50% of the world’s wetlands have been destroyed. Without suitable wetland habitat, many species could soon be homeless. Here are 11 reasons why you should care about wetlands:
1. Wetlands purify our water
Wetlands are great filters! They trap sediments and remove pollutants, which helps to purify water. This certainly beats expensive, human-made filtration systems.
2. Wetlands store our water to ensure supply during dry periods
Wetlands work like giant sponges. They store water and then slowly release it, and this helps to deal with dry seasons with little rainfall.
3. Wetlands can prevent floods
When rivers burst their banks, wetlands can store the excess water, and slow it down so it distributes more evenly over a floodplain. The roots of trees and other vegetation also help slow the speed of flood waters.
4. Wetlands recharge ground water
In the past, city planners either filled in wetlands areas or dammed them, adding pipes that would lead the water to the ocean as fast as possible. But now we know that wetlands allow water to soak into the ground, and to replenish the natural ground-water supply.
5. Wetlands help to control erosion
Sediments are also trapped by wetlands. In a semi-arid country like South Africa, the role of wetlands in trapping sediments, before the sediment-laden water joins a river course and just washes away, is really useful.
6. Wetlands provide shelter for juvenile fish
Fish larvae and fish fry (juveniles) use the calm, shallow waters of wetlands as a nursery.
7. Wetlands provide homes for animals and plants
Biodiversity is high around wetlands habitats. These areas provide food and shelter for many animals, in particular bird species such as herons, spoonbills and flamingos, and amphibians such as frogs.
8. Wetlands provide food for livestock
Wetlands provide good areas for grazing, and the variety of grasses, along with a supply of running water, can be beneficial to farming livestock.
9. Wetlands protect biodiversity
Many different kinds of creatures depend on wetlands – and on each other. The insects that are attracted to the plants provide food for other animals like fish, frogs and birds, who in turn attract other predators. The biodiversity of wetlands has produced some incredible specialist species that are only found in these habitats.
10. Wetlands provide locations for recreation
Zeekoevlei, Rietvlei Wetland Reserve and Rondevlei Nature Reserve are all examples of wetlands in Cape Town that people are able to visit and where they can enjoy nature walks, picnics, birding, fishing or even sailing. As more people flock to cities, these recreational spaces in nature become even more valuable.
11. Wetlands provide plants that can be used for houses and crafts
"Wetlands yield fuelwood for cooking, thatch for roofing, fibres for textiles and paper making, and timber for building. Medicines are extracted from their bark, leaves, and fruits, and they also provide tannins and dyes, used extensively in the treatment of leather," according to the World Wide Fund for Nature.
Where to see wetlands in Cape Town
In South Africa, most natural wetlands areas have been destroyed. In Cape Town, the remaining few are threatened by housing developments, agriculture, invasive flora and fauna, sewerage effluent and stormwater and agricultural run-off.
However, there are some spots that have been cared for, and are worth a visit.
Rietvlei Wetland Reserve
Rietvlei is a freshwater wetland on the floodplain of the Diep River, that drains into Milnerton Lagoon and finally into Table Bay. It comprises a permanent freshwater lake, shallow pans, extensive reedbeds and a tidal lagoon.
Rondevlei Nature Reserve
Rondevlei Nature Reserve is home to around 230 bird species, as well as a number of reptiles and mammals. Many come here to see the small hippopotamus population, as it’s the only reserve in Cape Town that is home to these creatures.
Zeekoevlei Nature Reserve
The water body of Zeekoevlei covers approximately 260ha and has an average depth of about 3.6m. It is fed by the Little and Groot Lotus Rivers on the northern side and, in turn, empties into False Bay on the southern side.
Zandvlei Estuary Nature Reserve
The Zandvlei wetland is an important habitat for birds, and has 166 species on its official list. It is also a vital home for amphibians and about 20 species of reptile such as tortoises, marsh terrapins, mole snakes and brown water snakes. Porcupines, grysbok, otters and mongoose can also occasionally be spotted.
Green Point Urban Park
The Grand Vlei in Green Point has been preserved and incorporated into this fantastic park. Stroll along the Wetlands Walk and learn more about the area's biodiversity. The Two Oceans Aquarium is also just a few kilometres down the road from here.
Wetlands under threat
Besides filling them in or damming them, humans have also damaged or destroyed wetlands by planting invasive alien species around them, draining them by piping the water out to sea, or directing filthy stormwater from cities towards them.
"A growing number of engineers and land-use planners are recognising the value of wetlands in the urban context," says Cape Town-based ecologist Lee Jones. "In response to serious water-quality problems, the current trend is to rip out the concrete, install litter traps, educate us errant littering citizens, and restore wetlands and water-courses to a more natural state.
"By restoring wetlands and improving the quality of water entering the streams and sea, fewer water-quality problems are encountered and everyone is able to live in a healthier environment."
What can I do to help wetlands?
- Visit the Two Oceans Aquarium and check out our Penguin Exhibit, brought to you by Old Mutual Finance, containing a river meander, tracing the journey of a pristine river from its mouth to its origin high up in the mountains. You will be able to see some of the animals that live in wetland areas here
- Explore a wetland area near you (check out the ones above if you live in Cape Town, or find others in the Western Cape) and learn about their value
- Use biodegradable products to clean your house (and yourself)
- Use organic products in your garden
- Save water – one drop wasted is a drop too much!
- Tell others about the importance of wetlands – share this blog post on Facebook or Twitter or email it to a friend
- Visit worldwetlandsday.org to find out more
Our hope is that future generations will be able to enjoy seeing wetland animals and plants in their natural habitat – and not just in an aquarium.