Amazon Floodplain Lake Food Web
Freshwater
Amazon Basin — Brazil, Peru, Colombia
Description
Amazon varzea floodplain lakes are seasonally connected to the main river channel, creating dynamic food webs that shift between isolation and connectivity. During high water, fish access flooded forest to feed on fruits and seeds. During low water, lakes shrink and concentrate fish, attracting predatory birds, caimans, and dolphins in spectacular feeding aggregations.
Trophic Pyramid
Level 5
Decomposers
Detritivorous catfish
Freshwater bacteria
Fungi
3 species
Level 4
Tertiary Consumers
Giant otter
Spectacled caiman
Amazon river dolphin
3 species
Level 3
Secondary Consumers
Peacock bass
Piranha
Anhinga
3 species
Level 2
Primary Consumers
Pacu
Silver dollar fish
Apple snails
3 species
Level 1
Producers
Floating macrophytes
Varzea forest trees
Periphyton
3 species
Apex Predators
Tertiary Consumers
Secondary Consumers
Primary Consumers
Producers
Key Interactions
- Seasonal flood pulse connects oxbow lakes to the main river, allowing fish migration
- Giant otters hunt cooperatively in family groups in floodplain lakes
- Low-water fish concentrations attract hundreds of wading birds and raptors
- Floating macrophytes provide refuge for juvenile fish from predators