Mmmm, Mudflats!

Mudflats

By Tim Marshall, OPS Ranger

Stuck in the mud
Have you ever been stuck it the mud? What was it like? What would it be like to live in the mud?

It stinks!
Q: What's that rotten egg smell?
A: It's rotting organic matter, stuck in the mud, without oxygen to help break it down.. As things slowly decompose, methane gas is created and trapped in the mud. The methane is what smells.

All you can eat!
Q: Are mudflats an all you can eat buffet? What's on the menu?
A: Mudflats are home to thousands of species of bacteria, insects, worms, shellfish and crustaceans. Many of the burrowing animals in this habitat are filter feeders, who siphon tiny particles of food from the nutrient-rich water.

Looking for life
This place looks mostly devoid of life - a wet wasteland... Wait! - Exploring the surface of a mudflat reveals the many holes and depressions created by the animals who live and feed here.

Oh give me a home
Q: Where can an animal live in a mud flat?
A: They can live on the surface or in shallow burrows beneath the surface.

Life is tough
Q: What makes it hard to live in a mud flat?
A: Low oxygen, wind, wave action, fresh water, pollution, salinity, sun, temperature extremes, salt, difficulty moving, and few hard surfaces for attachment. Food gathering is hard work.

Where’d all this mud come from?
Q: How did this place "get here"?
A: Mudflats are created by ocean tides which erode shorelines and then drop the sediment in a new location. This buildup of sentiment causes the flat, muddy environment that gives this natural community its name.

Where can I find a mud flat?
Mudflats exist on coastal water edges, & are under water during high tide and exposed to the air during low tide. Beaches are typically not muddy but sandy, because the waves carry away the fine soluble mud. Mud settles down in calm areas, like where mangroves calm the wave action, and behind barrier islands where it is not usually wavy, but calm.

Who lives in a mudflat?
Q: Which plants and animals stick it out in the mud?
A: Most plants cannot survive in a mudflat because of the constant tides. Microscopic algae is abundant, and a few hardy plants or plants that are able to take root in mud, such as eelgrass, can also be found. Worms living in the mudflats burrow and excavate, depositing lumps of mud, leaving slime trails, or pumping water through their filter feeding systems. Worms such as the parchment worm live in lavishly lined houses, encased in comfort.

Most animals living in the mudflats burrow into the sediment to avoid being swept away by tides,  to hide from predators, and to prevent exposure to sun, heat and drying out at low tide.

Animals living in mudflats include microscopic invertebrates, mollusks, crustaceans, snails and worms. These animals are mostly filter or deposit feeders.

The tide is low
Larger animals such as shore birds like reddish egrets, willets and roseate spoonbills often feed on the mollusks, crustaceans and other invertebrates which are exposed on mudflats during low tides.

The tide is high
During high tides, dolphins, sharks, stingrays and  fish such as snook and redfish may swim into the mudflats to feed.