Common Oak Fern vs Epaulard

Gymnocarpium dryopteris compared with Orcinus orca

Key Differences

• Common Oak Fern is Critically Endangered while Epaulard is Data Deficient.

Taxonomic Classification

Rank	Common Oak Fern	Epaulard
Kingdom	Plantae (Plants)	Animalia (Animals)
Phylum	Tracheophyta	Chordata (Chordates)
Class	Polypodiopsida (Polypodiopsida)	Mammalia (Mammals)
Order	Polypodiales (Polypodiales)	Cetacea (Whales & Dolphins)
Family	Cystopteridaceae	Delphinidae (Oceanic Dolphins)
Genus	Gymnocarpium	Orcinus (Orcas)
Species	Gymnocarpium dryopteris	Orcinus orca

Conservation Status

Common Oak Fern

CR — Critically Endangered

Epaulard

DD — Data Deficient

Population: ~50.0K

Trend: Unknown ?

Physical Characteristics

Attribute	Common Oak Fern	Epaulard
Diet	—	Carnivore
Average Lifespan	—	50 years
Average Length	—	8.0 m
Average Weight	—	5.4 t

Habitat & Geographic Range

Common Oak Fern

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 across Europe (6 countries) and North America (Canada, United States). Currently classified as Critically Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Epaulard

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 11 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Asia (Taiwan), Europe (4 countries), and South America (Colombia, Ecuador, Venezuela).

Common Oak Fern

<em>Gymnocarpium dryopteris</em>, the common oak fern, is a delicate terrestrial fern in the family Cystopteridaceae (or Woodsiaceae, depending on classification). Despite its common name, the species is not specifically associated with oak trees; rather, it typically grows in cool, moist, shaded environments including boreal and mixed forests, rocky woodland slopes, stream banks, and shaded cliff faces. <em>Gymnocarpium dryopteris</em> spreads by rhizomes and forms low, spreading colonies with characteristic triangular, three-pinnate fronds that emerge from a slender creeping rootstock. Its geographic range spans Europe and North America, with populations in cool temperate and boreal zones. The species is currently assessed as Critically Endangered in certain regional assessments, suggesting that particular populations face severe decline, likely due to habitat loss, forest fragmentation, and altered hydrology, even if the species retains a broader global range. Biological traits such as lifespan, body size, and diet remain poorly documented at a standardized population level. <em>Gymnocarpium dryopteris</em> is a characteristic indicator of undisturbed cool woodland habitats and is valued for both its ecological role in forest understoreys and its aesthetic appeal.

Epaulard

The largest member of the dolphin family, orcas reach up to 9 meters and 6 tonnes and are found in every ocean from Arctic to Antarctic. Apex predators living in matrilineal pods with distinct dialects, hunting strategies, and cultural traditions that differ between populations. Some populations specialize in fish, others in marine mammals. No natural predators; orcas sit at the top of every marine food chain they inhabit.

Shared Countries

Both species can be found in 3 countries:

🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden