Chesil Beach Intertidal Food Web
Marine
British Isles — Southern England coast
Description
Rocky intertidal zones along temperate coastlines support vertically zonated food webs compressed into narrow tidal bands. Sessile organisms like barnacles and mussels compete fiercely for space, while predatory sea stars and whelks exert top-down control. Wave exposure, desiccation, and predation create a dynamic mosaic of species assemblages.
Trophic Pyramid
Level 5
Decomposers
Intertidal bacteria
Amphipods
Isopods
3 species
Level 4
Tertiary Consumers
Common starfish
Herring gull
Oystercatcher
3 species
Level 3
Secondary Consumers
Dog whelk
Shore crab
Beadlet anemone
3 species
Level 2
Primary Consumers
Common limpet
Acorn barnacle
Periwinkle
3 species
Level 1
Producers
Bladder wrack
Channelled wrack
Sea lettuce
3 species
Apex Predators
Tertiary Consumers
Secondary Consumers
Primary Consumers
Producers
Key Interactions
- Sea stars prey on mussels, preventing competitive exclusion of barnacles
- Limpets graze microalgae, maintaining bare rock for barnacle settlement
- Dog whelks drill through barnacle shells using a radula and acid secretion
- Vertical zonation is driven by desiccation tolerance and predation intensity