Big Water Crayfish vs Laysan Duck

Cambarus robustus compared with Anas laysanensis

Key Differences

• Big Water Crayfish is Least Concern while Laysan Duck is Critically Endangered.

Taxonomic Classification

Rank	Big Water Crayfish	Laysan Duck
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Arthropoda (Arthropods)	Chordata (Chordates)
Class	Malacostraca (Crustaceans)	Aves (Birds)
Order	Decapoda (Decapoda)	Anseriformes (Anseriformes)
Family	Cambaridae	Anatidae
Genus	Cambarus	Anas
Species	Cambarus robustus	Anas laysanensis

Evolutionary Relationship

Big Water Crayfish and Laysan Duck share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Big Water Crayfish

LC — Least Concern

Laysan Duck

CR — Critically Endangered

Physical Characteristics

Attribute	Big Water Crayfish	Laysan Duck
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Big Water Crayfish

Habitat

Typically found in marine, freshwater, and terrestrial environments.

Range

Found in United States.

Laysan Duck

Habitat

Found across multiple habitat types including temperate broadleaf and mixed forests, temperate coniferous forests, and Mediterranean forests and woodlands within the Palearctic biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Distributed across Belgium, France, Netherlands, Norway, and United Kingdom. Currently classified as Critically Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Big Water Crayfish

The Big Water Crayfish (Cambarus robustus) is a species in the genus Cambarus. It is currently classified as Least Concern on the IUCN Red List. Typically found in marine, freshwater, and terrestrial environments.

Laysan Duck

Laysan Duck (Anas laysanensis) is classified as Critically Endangered (CR) on the IUCN Red List. Facing an extremely high risk of extinction in the wild due to severe population decline and habitat loss.