Bryan McAllister’s personal reference notebook
July 30, 2026Short & citedBlog
Civic Viewpoint.
A quiet encyclopedia with a personal desk
Kept by Bryan McAllister — short guides, clear facts, and the Canadian angle when it matters.
Field Notes • Biology

Shrimp

Shrimp are small aquatic crustaceans found in marine and freshwater environments.

Updated July 30, 20261 min readCited sources

Shrimp are small aquatic crustaceans with ten legs, found in marine and freshwater environments. Most species are omnivorous scavengers, feeding on algae, plankton, and organic debris.

Classification

Shrimp are crustaceans, not insects, and belong to the order Decapoda, meaning they have ten legs. They are part of the arthropod group, which also includes insects and spiders, but shrimp are distinctly different in body structure and evolutionary history.

Habitat and ecology

Shrimp occur in oceans, estuaries, rivers, lakes, and even aquariums. Many species help recycle organic material by feeding on detritus, algae, and other tiny food sources, playing a key role in aquatic ecosystems.

Diet and feeding

Wild shrimp generally eat a broad mix of algae, plankton, decaying plant and animal matter, and tiny organisms. Aquarium shrimp are often fed prepared shrimp foods and graze on biofilm and leftovers, making them easy to care for in home tanks.

In short

  • Shrimp are decapod crustaceans with ten legs.
  • They live in both saltwater and freshwater habitats.
  • Most are omnivores or scavengers of algae, plankton, and detritus.
  • Shrimp are not insects — they belong to a separate arthropod group.
Canadian angle

Shrimp are widely consumed in Canada and are important in Canadian seafood markets, especially for Atlantic and Pacific fisheries and aquaculture. Canadian readers may also encounter shrimp in aquarium keeping and marine ecology topics.

Quick questions

What do shrimp eat?
Most shrimp are opportunistic omnivores or scavengers that eat algae, plankton, detritus, biofilm, decaying plant matter, and small organic remains, depending on species and habitat.
Are shrimp insects?
No. Shrimp are crustaceans, not insects. Both are arthropods, but they are different groups with different body structures and evolutionary histories.
What is the difference between shrimp and prawns?
The terms are used inconsistently across regions. In everyday language they may refer to different-looking or differently sized decapod crustaceans, but scientifically the distinction is not always clear-cut.

Sources

  1. Encyclopaedia Britannica — https://www.britannica.com/animal/shrimp
    Supports: Shrimp are decapod crustaceans; general biology, classification, and habitats.
  2. Food and Agriculture Organization of the United Nations — https://www.fao.org/fishery/en/species/2448
    Supports: Shrimp and prawns as commercially important crustaceans; broad diet and habitat context.
  3. Animal Diversity Web — https://animaldiversity.org/accounts/Decapoda/
    Supports: Decapod classification and the fact that decapods have ten legs.
  4. Merriam-Webster — https://www.merriam-webster.com/grammar/shrimp-vs-prawn-difference
    Supports: Regional and usage differences between shrimp and prawns.
  5. Fisheries and Oceans Canada — https://www.dfo-mpo.gc.ca/index-eng.html
    Supports: Canadian context for shrimp as a seafood resource and marine species.