Image Credit: Phil Barnes, RSPB Images
It’s World Wetlands Day!
Wetlands are areas that are either permanently or seasonally covered by water. There are many different types of wetland (rivers, marshes, estuaries, floodplains and lakes are all examples). Saltholme contains many types of wetland, ranging from estuarine habitats to ponds, lakes and reedbeds.
As a wetland reserve, it’s only right that we celebrate this day. But why are wetlands so special? Well, there are many reasons! We will go through some of the key ones...
Biodiversity Hotspots
Image Credit: Kevin Harwood, RSPB Images
Wetlands are some of the most biodiverse habitats on the planet. Biodiversity is a measure of how many species live and interact in an area. The greater the variety of plants, animals, fungi, algae and anything else that may be present, the higher the biodiversity.
To put it into perspective, 40% of the world’s plants and animals rely on wetland habitats (Wildfowl and Wetlands Trust, 2022).
Image Credit: Lockhart Horsburgh
Many of the species that visit Saltholme are doing so because of its wetland nature; common terns migrate here from Gambia every summer because of the good food supply and nesting sites this habitat provides. The reedbeds here provide a refuge for Britain’s most endangered mammal- the water vole. Goose and duck species use Saltholme as a stopover point on their migration routes, and many stay here over winter, because of the abundance of food. All this is just in the UK- scale that up to wetlands around the world, and you can start to see just how important they are.
Carbon Sinks
Image Credit: David Palmar, RSPB Images
A carbon sink is something that absorbs and stores carbon dioxide, preventing this gas from entering the atmosphere. Carbon dioxide is known as a greenhouse gas; it absorbs heat radiating from the surface of the earth, preventing this energy from being lost from the planet. This warms up the earth, leading to global warming and climate change. Of course, the release of carbon dioxide has happened naturally for millennia. The issue now is the amount of carbon dioxide being released- much larger than natural or ‘background’ levels- from human activity.
But there is hope! Wetlands are the most effective carbon sinks on the planet. The plants growing in these habitats absorb carbon dioxide to make food, locking this carbon away in their tissues. Some carbon dioxide is also absorbed by the mud and sediments in wetlands, and even by the water itself.
This is why there are not many trees on our reserve at Saltholme. Trees are themselves fantastic carbon sinks, but wetlands are actually the most effective carbon sinks on the planet! The presence of trees on wetlands can actually REDUCE their effectiveness as carbon sinks, as the roots disturb carbon-rich sediments and therefore can cause the release of carbon dioxide.
Protection for Humans
Image Credit: Andy Hay, RSPB Images
Wetlands are not just good for wildlife- they also benefit humans! Of course, they do this in lots of different ways. They are beautiful places to spend time outdoors, they help us combat climate change, and they provide a refuge for species that we are yet to know everything about. They even clean the water for us!
But one of the main benefits wetlands pose for humans is their protection from flooding. They do this by several means:
The estuarine habitat at Greatham Creek, and the series of pools at Saltholme, are perfect examples of this important natural defence against flooding.
A shrinking habitat
Image Credit: Lydia Cave
The importance of wetlands is compounded by their threatened nature. Some areas of the UK have lost over 90% of their wetland habitat through conversion to other land uses and habitat degradation. Peat-based fuel and peat compost continues to degrade the peatlands that absorb so much of our carbon and reduce our flood risk.
With so many of our wetlands threatened, these habitats and the species that live there become even more precious.
Our reserve at Saltholme was created to protect these valuable ecosystems and the wide variety of wildlife that relies on them. How we manage and improve our site is all to conserve and expand wetlands for future generations.
So, there you have it!
As you can see, wetlands are vitally important for the health of our planet, our wildlife, and our own communities. Of course, every habitat is important and needs to be protected. But today is the day of wetlands, so why not visit Saltholme this week and see this amazing ecosystem for yourself?
References and Additional Reading
Royal Society for the Protection of Birds (2022). Common Tern [webpage]. Accessed through https://www.rspb.org.uk/birds-and-wildlife/wildlife-guides/bird-a-z/common-tern/ [last accessed 30/01/2022].
The Wildlife Trusts (2022). Natural Solutions to Climate Change: Wild Wetlands [webpage]. Accessed through https://www.wildlifetrusts.org/natural-solutions-climate-change/wild-wetlands [last accessed 02/02/2022].
The Wildlife Trusts (2022). Water Vole [webpage]. Accessed through https://www.wildlifetrusts.org/wildlife-explorer/mammals/water-vole [last accessed 30/01/2022].
The Wildlife Trusts (2022). Wetlands [webpage]. Accessed through https://www.wildlifetrusts.org/habitats/wetlands [last accessed 02/02/2022].
Wildfowl and Wetlands Trust (2022). Wetlands [webpage]. Accessed through https://www.wwt.org.uk/discover-wetlands/wetlands/ [last accessed 30/01/2022].
Wildfowl and Wetlands Trust (2022). Why Wetlands? [webpage]. Accessed through https://www.wwt.org.uk/our-work/why-wetlands/ [last accessed 30/01/2022].