Columbia River Signal Crayfish vs Green Sea Turtle

Pacifastacus leniusculus compared with Chelonia mydas

Key Differences

• Columbia River Signal Crayfish is Not Evaluated while Green Sea Turtle is Endangered.

Taxonomic Classification

Rank	Columbia River Signal Crayfish	Green Sea Turtle
Kingdom same	Animalia (สัตว์)	Animalia (สัตว์)
Phylum	Arthropoda (สัตว์ขาปล้อง)	Chordata (สัตว์มีแกนสันหลัง)
Class	Malacostraca (Crustaceans)	Reptilia (สัตว์เลื้อยคลาน)
Order	Decapoda (Decapoda)	Testudines (เต่า)
Family	Astacidae	Cheloniidae (Sea Turtles)
Genus	Pacifastacus	Chelonia (Green Sea Turtles)
Species	Pacifastacus leniusculus	Chelonia mydas

Evolutionary Relationship

Columbia River Signal Crayfish and Green Sea Turtle share a common ancestor at the Kingdom level: Animalia. (สัตว์)

Conservation Status

Columbia River Signal Crayfish

NE — Not Evaluated

Green Sea Turtle

EN — Endangered

Population: ~85.0K

Trend: Decreasing ↓

Physical Characteristics

Attribute	Columbia River Signal Crayfish	Green Sea Turtle
Diet	—	Herbivore
Average Lifespan	—	80 years
Average Length	—	1.2 m
Average Weight	—	200.0 kg

Habitat & Geographic Range

Columbia River Signal Crayfish

Habitat

Typically found in marine, freshwater, and terrestrial environments.

Range

Widely distributed across Asia (Japan), Europe (26 countries), and North America (United States).

Green Sea Turtle

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and tropical and subtropical grasslands and savannas, among 8 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Distributed across Australia, Brazil, Costa Rica, Indonesia, and Mexico. Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Columbia River Signal Crayfish

<em>Pacifastacus leniusculus</em>, the Columbia River signal crayfish, is a freshwater crustacean in the family Astacidae native to the Pacific Northwest of North America and widely introduced across Europe, Japan, and other regions. This species has not been evaluated by the IUCN but is recognised as one of the most ecologically damaging invasive freshwater species in Europe, present in 26 European countries, Japan, and its native range in the United States. Signal crayfish are large, aggressive, and highly fecund, capable of displacing native crayfish species through competition and through transmission of crayfish plague, a disease caused by the oomycete <em>Aphanomyces astaci</em>, to which North American crayfish have evolved resistance but European species have not. This species inhabits a wide range of freshwater environments including rivers, streams, lakes, and estuaries, as well as adjacent terrestrial habitats. Signal crayfish are omnivores, consuming aquatic plants, invertebrates, fish eggs, and organic detritus, and their burrowing activity can destabilise stream banks and increase turbidity. Management of invasive populations is a major focus of freshwater conservation in Europe. Biological traits of this species remain poorly documented in the scientific literature.

Green Sea Turtle

The green sea turtle is one of the largest sea turtles. They are named for the green color of their cartilage and fat, not their shells.