Benthos, aka wader food.

So what exactly are all those waders eating out there on the mudflats with such enthusiasm?

The answer is benthos, aka wader food.

Benthos: the flora and fauna found on the bottom, or in the bottom sediments, of a sea or lake.

There are two types of benthos:

Zoobenthos
Phytobenthos

Zoobenthos:  comprises the animals belonging to this group.
Phytobentos:  comprises the plants belonging to this group.

They can be subdivided by size:

Macrobenthos
Meiobenthos
Microbenthos

Macrobenthos: Visible organisms of a length greater than 1mm. Includes polychaete worms (worms with bristles like lugworms etc.), bivalves (seashells with two halves like cockles, oysters, clams and mussels), echinoderms (star fish, sea urchins etc.), sea anenomes, corals, sponges, sea squirts, turbellarians (flatworms), crabs, lobsters and cumaceans (comma shrimps).

Meiobenthos: Organisms that are between 1mm and 0.1mm in size. Includes nematodes (roundworms), foraminiferans, water bears, gastrotriches (hairybacks), copepods and
ostracodes (seed shrimps).

Microbenthos: Organisms under 0.1mm in size. Includes bacteria, diatoms (algae), ciliates, amoeba and flagellates.

They can also be divided by their location:

Endobenthos
Epibenthos
Hyperbenthos

Endobenthos: living buried, or burrowing in the sediment
Epibenthos: living on top of the sediments
Hyperbenthos: living just above the sediment

Wader bills have developed to take advantage of all forms of benthos as prey. Continue reading here.