Celebrate Biodiversity on World Wetlands Day!
|Download this infographic (and more) from the World Wetland Day's website:|
Celebrated annually on February 2nd, World Wetlands Day marks the anniversary of the 1971 Ramsar Convention, also known as the Convention on Wetlands, an international treaty created to support the conservation and sustainable use of wetlands around the world. Currently, there are over 2,300 Ramsar sights, or Wetlands of International Importance, that have been designated worldwide - which is good news considering the sad state of our world's wetlands.
Since 1970, 35% of wetlands have been lost, at a rate three times greater than the loss of forests (source). In the continental United States, over half of all wetlands have been destroyed since the 1700's (source, source). California alone has lost between 90 and 95% of its wetlands.
|Sunset at Merced NWR, a Ramsar Wetland of International Importance, right here in California's San Joaquin Valley!|
World Wetlands Day, first celebrated in 1997, was created so that government agencies, non-government organizations, communities and citizens could come together to raise public awareness for the value of wetlands and their benefits to people and the planet. People will only work to save what they love, and they can only love something they know.
If a person has never watched the breeze ripple across reflections of clouds in the still waters of a reed-lined pool, seen a kaleidoscope of wildflowers blooming in concentric rings around vernal pools, watched the feeding frenzy of avian life around tidal wetlands, or felt his or her own soul lifted on the wings of tens of thousands of waterfowl rising in unison from the surface of the water, what incentive is there to preserve a local wetland?
But first, a few questions need answering.
|The San Luis NWR, another part of the San Joaquin Valley's own Ramsar Wetland of International Importance|
What, exactly, is a Wetland?
Wetlands, areas of transition between aquatic and terrestrial habitats that are either covered by or saturated with water for at least part of the year, exist in nearly every climate worldwide, on every continent except Antarctica. Sources of water for wetlands include groundwater from aquifers, seeps or springs, rainwater and runoff, floodwater from nearby rivers or lakes, and seawater inundation, as in the case of tidal salt marshes. Just about every landscape in California hosts some type of wetland. The coast, of course, has its tidally influenced salt marshes, while inland valleys and grasslands have vernal pools and floodplains. High in the mountains are wet meadows and fens, and even in the hottest, driest desert parts of the state, wetlands take the form of fan palm oases and springs.
Wetlands are generally grouped into three broad categories:
Marshes are essentially flooded grasslands, areas of saturated or flooded land dominated by grasses and aquatic plants. They may be tidally influenced, consisting of brackish or salt water, or inland freshwater marshes not influenced by the tide. Marshes are the main types of wetlands represented across California.
Tidal saltwater marshes are found along the coast, where they range in salinity from freshwater in the upper marsh to highly saline in the lower intertidal marsh. They typically support a thick mat of low-growing, salt-tolerant plants, many of which have special adaptations, like succulent leaves, to help them withstand harsh conditions.
Read about California's Coastal Salt Marsh by following this link, and South Carolina's Salt Marshes and Tidal Creeks here.
|Looking across Elkhorn Slough, a Ramsar Wetland of International Importance on the coast of Central California.|
Freshwater marshes occur in level, low-lying areas where water from precipitation and runoff accumulates, often along the shallow edges of lakes and ponds. Reedlike plants typify freshwater marshes, and common types found in California are rushes, tules, cattails and sedges.
Wet meadows, a type of freshwater marsh, are areas of grasses, sedges, rushes and wildflowers growing over poorly drained soil, often in forest clearings. They may be dry for much of the year, and hold standing water only during the wet season. Picturesque wet meadows abound in forest clearings in the Sierra Nevada. Wildlife thrives along the edges of meadows, at the interface between dense forest and open habitat. Wet meadows provide this crucial habitat, yet like other wetlands, wet meadows have been subjected to draining and filling in order to make them "productive." In the Sierra, they have also been heavily grazed.
|A wet meadow in Sequoia National Park|
Vernal pools are something of a grassland specialty here in California, occurring over clay soil or hardpan on terraces around the valley as well as on the valley floor itself. These beautiful wetlands range in size from puddles to wide, shallow lakes and vary greatly from year to year. In wet years, pools fill and may even overflow, connecting to other pools via vernal swales to form a wetland complex. Vernal pools are the epitome of a seasonal wetland. In the early spring they create beautiful pools across a lush green landscape, each pool ringed with wildflowers. But come summer, the pools dry up, the grasses turn brown, and the clay soil turns to dust. No one would ever guess wetland habitat is found in the dry golden hills surrounding the valley.
|The remnants of a vernal pool, the shape of which is marked by the presence of wildflowers (in this case, fleeting Meadowfoam), in the hills of eastern Stanislaus County.|
The prairie potholes region of North America extends from central Canada through the northern Midwestern states. The potholes formed when chunks of buried glacial ice, remnants from the last ice age, melted, forming bowl-shaped depressions that filled with water. Some potholes fill with water seasonally while others are permanent. Over half of North America's migratory waterfowl depend on prairie potholes for feeding and breeding, and yet the region has been highly altered through draining and conversion to agriculture and only 40-50% of prairie pothole wetlands remain intact.
Think of swamps as flooded forests, permanently saturated, or nearly so, and dominated by trees. The two main types of swamp found in North America are forested freshwater swamps, like the bottomland hardwood swamps and bayous found in the southern United States, and saltwater shrub swamps, such as the mangrove swamps of Florida. (We don't really have any true swamps in California, though flooded riparian forests might come close.)
Click here to read more about South Carolina's Cypress-Tupelo Swamps.
Bogs and Fens:
While marshes and swamps are common in warm climates, bogs are typically found in the cold, northerly climes of North America and Europe, as well as at high elevations in mountains like California's Sierra Nevada. Other names for these habitat types include moors in Europe, and muskegs in Canada.
Bogs and fens form as vegetation grows in a wet area, often encroaching into a shallow body of water until it is entirely covered with plants. As the plants die, plant matter builds up, year after year, forming a dense, spongy layer of partially decayed vegetation called peat. The differences between a bog and a fen are subtle. While bogs receive their water directly from precipitation, the source of water for fens is generally from runoff, drainage, or ground water. Peat bogs generally have very acidic, nutrient-poor soil that supports a unique vegetation type, while the soil of fens is more productive. Bogs in California are rare (there might be a few along the north coast) but a good example of a fen can be seen near Happy Isles in Yosemite Valley.
|The sign at the Happy Isles Fen in Yosemite Valley (because for whatever reason, I took a picture of the sign... and not the fen itself.)|
An additional type of wetland found in the Colorado Desert of California is the fan palm oasis. Fan palms, California's only native palm, grow along fault lines where groundwater seeps upwards. The presence of surface water and shade at desert oases make these wetlands the most productive desert habitats, and a greater variety of animals can be found here than anywhere else in the desert.
|An oasis at Dos Palmas Preserve, near the Salton Sea.|
What do wetlands do? Why are they so important?
Wetlands are, without a doubt, one of the most valuable ecosystems on Earth. The extent of their functions are wide and multifaceted, but a few of their main functions, or ecosystem services, are as follows:
Surface water storage and ground water recharge:
Wetlands act as giant sponges, slowing water runoff after storms, soaking up excess water and holding onto it. They function as sinks for storing excess water which could otherwise cause flooding, and by preventing rapid runoff, the water stored in wetlands is able to slowly percolate back into the ground, replenishing aquifers. (At least, we think aquifers can be replenished. That's another topic for another day!)
Wetlands, particularly those along the coast, act as buffers against powerful storm surges, slowing and dissipating otherwise damaging waves and currents that have the ability to erode shorelines, even wash away entire beaches and coastal communities. Nowhere have I seen a better example of this than along the low-lying coastal communities around Charleston, South Carolina. We visited on a calm, summer day, but looking out over the grasses of the coastal salt marsh it was easy to see how acres and acres of dense vegetation protects an otherwise fragile and vulnerable coastline - built up with very expensive and beautiful houses!
Similar to the previous two functions, inland wetlands have the ability to absorb and trap huge amounts of water that seasonally overflows the banks of rivers and lakes. In California's Central Valley, this was an important function of riparian wetlands, and wetlands surrounding the gargantuan - now extinct - Tulare Lake. As snow in the Sierra Nevada range melted and flowed down rivers into the Central Valley, those rivers flooded, and water flowed out into ancient floodplains to be held and slowly reabsorbed into the earth. Now, of course, this beautifully orchestrated system has been thrown completely out of whack by the building of a mind-boggling labyrinth of reservoirs, dams, levees and canals, all of which are highly regulated. Every so often, though, there is still flooding, as there was a couple of years ago along the San Joaquin River, and the value of restored wetlands, like those at the San Joaquin River National Wildlife Refuge, is allowed to shine.
Nature's own water-treatment facilities:
Wetlands are remarkably efficient at improving water quality, as their plants, fungi and algae filter sediment, nutrients, waste and toxins out of the water. Pesticides, chemicals, and even heavy metals wash into wetlands from surrounding urban, industrial and agricultural areas. As water flows slowly through wetland vegetation, sediments laden with both nutrients and toxins are filtered out, settling to the bottom where they are either buried or broken down, rather than being washed into aquatic ecosystems beyond. Without wetland vegetation, aquatic habitats would become infiltrated with sediment and contaminated by runoff laden with excess nutrients and toxic chemicals.
Carbon sinks to counteract climate change:
Wetland plants take up carbon dioxide from the atmosphere through the process of photosynthesis, storing the carbon in living and dead plant material as well as in the highly organic mud. Coastal habitats like salt marshes sequester even more carbon than terrestrial forests! Additionally, peat bogs store an estimated 30% of land-based carbon.
Support biodiversity, and in turn, the economy:
At the interface of terrestrial and aquatic habitats, wetlands support an incredible amount of biodiversity, with up to 40% of all species worldwide living or breeding in wetlands (source). Many species we rely on for food spend at least part of their life cycle in wetlands. Ramsar estimates that the livelihoods of over 1 billion people worldwide are dependent on healthy and productive wetlands. In California, wetlands support more species of plants and animals than all of the other habitat types found in the state, combined!
Places of natural beauty and outdoor recreation (which also supports the economy):
Public access to wetlands allows local residents and tourists alike to enjoy outdoor recreational activities, such as bird and wildlife watching, fishing, waterfowl hunting, boating, kayaking, and hiking. The US Fish and Wildlife Service estimates that Americans spend over $100 billion annually on wetland-related recreational activities (source, source). I believe (and there are studies to back me up on this) that immersion in nature is imperative for our overall health and well-being, and wetlands provide tranquil settings in which to enjoy fresh air and sunshine while taking a contemplative stroll through a beautiful habitat.
Why do wetlands need protecting?
Throughout much of human history, and certainly the United States' history, wetlands have been seen as useless wastelands, good for nothing unless they are highly altered, or "reclaimed." Their waterlogged ground can't support infrastructure or agriculture, and their typical assemblage of wildlife is generally considered less than endearing: alligators, water moccasins and mosquitoes.
While wetland draining started early in the history of our nation (the US Capitol is in fact built on a drained wetland), "progress" on wetland "reclamation" projects really increased during the 1950's through the 1970's. As a result of wetland loss, a number of wetland-dependent fish, many of which are commercially important, have become scarce, numbers of ducks and other waterfowl that breed in and migrate through wetlands have fallen, and biodiversity is threatened. When wetlands are degraded they no longer provide the host of beneficial environmental services we so depend on, like filtering our water and protecting our shorelines from erosion.
Threats to wetlands come in other forms besides just draining and filling (though that one is the most obvious). Water from wetlands may be diverted through dikes and canals; it may be dredged for boat navigation or dammed to create ponds; it may even be increased, to the detriment of the wetland, by the build up of nearby urban areas, as impervious surfaces (roads, buildings, parking lots, etc.) increase pollutant-laden runoff into wetlands.
Although wetlands are excellent water filters, they can only take so much. Excess pollutants are carried into wetlands from a variety of sources, including agricultural and residential chemical pesticide and herbicide runoff, heavy metals from mining and industry, leaky landfills, oil dumping and spills, marinas where boats stir up sediment and leak oil, even from the very air itself. On top of all this, the introduction and spread of non-native plants and livestock grazing harm wetland vegetation.
|A dubious honor: California leads the nation in percentage of wetlands lost.|
Okay, maybe I've finally convinced you. Now, you may be wondering (I hope you're wondering),
"What can I do to help protect and restore wetlands?"
- Support local organizations that protect and restore wetlands, through your vote, voice and donations. (One easy way to do this is by purchasing duck stamps)
- Educate yourself and others on current wetland issues - spread the word! One reason I think wetlands are allowed to disappear is simply because too few people know and appreciate them.
- Volunteer your time. Get in touch with your local wildlife refuge or other conservation organization to find out about work days and other volunteer opportunities in and around wetlands.
- Avoid (or at least reduce) the use of chemical fertilizers, pesticides, herbicides, and cleaning products around your home and yard.
- Never litter, pollute the water, pour oil down storm drains, etc.
- Plant native plants and avoid the use of non-native invasive plant species (which often escape cultivation and wind up choking native plants out of wetlands).
- Experience wetlands for yourself, and share them with your friends and family. Many wetlands across the country invite visitors to walk along boardwalks and maintained pathways lined with interpretive signs. (Be sure to bring your binoculars!) In my opinion, there is no substitution for the education gained through personal experience!
I visited South Carolina's two Ramsar sights last summer (Congaree National Park and Francis Biedler Forest) and Nevada's Ramsar site at Ash Meadows National Wildlife Refuge a few years ago. These places are so different from each other - one is tucked into Eastern hardwood forests, the other hidden in the vast Great Basin Desert - and yet both are beautiful, critical habitats.
Central California's Wetlands of International Importance include Bolinas Lagoon, San Francisco Bay/Estuary and Elkhorn Slough. Even closer to my home and heart is the Grasslands Ecological Area of Merced county, which was designated as a Ramsar Wetland of International Importance on February 2, 2005. I highly recommend a visit to any or all of these inspiring places!
Explore all of the Ramsar Wetlands worldwide by following this link.
Or, take a virtual tour with me! Click on the links below to explore some of California's most critical restored wetland habitat.
The Grasslands Ecological Area, a Ramsar site in California's Great Central Valley which encompasses:
Find out more (and check my facts!)
For a thorough read, check out Ramsar's Global Wetland Outlook: State of the world's wetlands and their services to people 2018