common nut clam vs Oso Polar

Nucula nucleus compared with Ursus maritimus

Key Differences

• common nut clam is Least Concern while Oso Polar is Vulnerable.

Taxonomic Classification

Rank	common nut clam	Oso Polar
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Mollusca (moluscos)	Chordata (cordados)
Class	Bivalvia (Bivalvia)	Mammalia (mamíferos)
Order	Nuculida (Nuculida)	Carnivora (carnívoros)
Family	Nuculidae	Ursidae (Bears)
Genus	Nucula	Ursus (Bears)
Species	Nucula nucleus	Ursus maritimus

Evolutionary Relationship

common nut clam and Oso Polar share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

common nut clam

LC — Least Concern

Oso Polar

VU — Vulnerable

Population: ~26.0K

Trend: Decreasing ↓

Physical Characteristics

Attribute	common nut clam	Oso Polar
Diet	—	Carnivore
Average Lifespan	—	25 years
Average Length	—	2.4 m
Average Weight	—	450.0 kg

Habitat & Geographic Range

common nut clam

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

Oso Polar

Habitat

Found across multiple habitat types including temperate broadleaf and mixed forests, temperate coniferous forests, and boreal forests and taiga, among 4 distinct biome types within the Palearctic biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Found in Norway. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

common nut clam

<em>Nucula nucleus</em>, the common nut clam, is a small marine bivalve mollusk in the family Nuculidae, among the most primitive living bivalves in terms of evolutionary lineage. This deposit-feeding species typically burrows into soft sediments — muddy and sandy substrates — in coastal and subtidal marine environments. <em>Nucula nucleus</em> uses its elongated palp proboscides to sort organic particles and detritus from sediment, making it a key functional contributor to benthic nutrient cycling. Its geographic range spans European Atlantic and Mediterranean coasts, with documented occurrences in Belgium, Denmark, Norway, and Sweden, typically in sheltered bays, estuaries, and sublittoral soft-bottom habitats. The species is currently assessed as Least Concern by the IUCN. Biological traits such as lifespan, body size, and diet remain poorly documented at a population level for this species in formal assessments, though it is known as a selective deposit feeder. The common nut clam plays an important role in benthic community structure and sediment processing, and serves as prey for demersal fish, sea stars, and other bottom-dwelling predators across its European range.

Oso Polar

El mayor carnivoro terrestre de la Tierra, el oso polar puede superar los 700 kg y se encuentra en el hielo marino del Artico, desde Canada hasta Rusia. Es un mamifero marino altamente especializado que depende del hielo marino para cazar focas anilladas y barbadas. Excelente nadador capaz de cubrir grandes distancias en agua abierta. Clasificado como Vulnerable, sus poblaciones soportan una presion severa por la rapida perdida de hielo marino artico debida al cambio climatico.

Shared Countries

Both species can be found in 1 countries:

🇳🇴 Norway