ハシグロアビ vs Polar bear

Gavia immer compared with Ursus maritimus

Key Differences

ハシグロアビ is Not Evaluated while Polar bear is Vulnerable.

Taxonomic Classification

Rank	ハシグロアビ	Polar bear
Kingdom same	Animalia (動物)	Animalia (動物)
Phylum same	Chordata (脊索動物)	Chordata (脊索動物)
Class	Aves (鳥類)	Mammalia (哺乳類)
Order	Gaviiformes (アビ目)	Carnivora (ネコ目)
Family	Gaviidae	Ursidae (Bears)
Genus	Gavia	Ursus (Bears)
Species	Gavia immer	Ursus maritimus

Evolutionary Relationship

ハシグロアビ and Polar bear share a common ancestor at the Phylum level: Chordata. (脊索動物)

表示 Phylum: Chordata

Conservation Status

ハシグロアビ

NE — Not Evaluated

Polar bear

VU — Vulnerable

Population: ~26.0K

Trend: Decreasing ↓

Physical Characteristics

Attribute	ハシグロアビ	Polar bear
Diet	—	Carnivore
Average Lifespan	—	25 years
Average Length	—	2.4 m
Average Weight	—	450.0 kg

Habitat & Geographic Range

ハシグロアビ

Habitat

Typically found in various aerial, terrestrial, and aquatic environments.

Range

Distributed across Belgium, Denmark, Norway, Sweden, and United States.

Polar bear

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.

ハシグロアビ

<em>Gavia immer</em>, the common loon or great northern diver, is a large aquatic bird in the family Gaviidae, known for its haunting, yodeling calls across northern lakes. It is found in Belgium, Denmark, Norway, Sweden, and the United States, breeding on freshwater lakes in boreal and subarctic regions and wintering along marine coastlines. The common loon is adept in aerial, terrestrial, and aquatic environments, though it is most highly specialized for diving, using its strong feet positioned far back on its body to pursue fish underwater. It typically feeds on fish, supplemented by crustaceans and aquatic invertebrates. Its striking summer plumage features a black-and-white checkered back and a deep black head with a characteristic white necklace pattern. The species has not been evaluated for IUCN conservation status. Common loons require clear, fish-rich lakes for successful breeding and are sensitive to water quality degradation and human disturbance at nesting sites. Their distinctive calls are emblematic of wilderness in North America and Scandinavia.

Polar bear

地球上で最大の陸上肉食動物であるホッキョクグマは700kgを超えることがあり、カナダからロシアまでの北極海氷域全体に分布する。ワモンアザラシとヒゲアザラシを狩るために海氷に依存する高度に特化した海洋哺乳類である。広大な距離を泳ぐことができる優れた泳者でもある。脆弱種に指定されており、気候変動による急激な北極海氷の消失で個体群が深刻な圧力を受けている。