Coastal Silver-stiletto vs Collared Petrel

Acrosathe annulata compared with Pterodroma brevipes

Key Differences

• Coastal Silver-stiletto is Least Concern while Collared Petrel is Vulnerable.

Taxonomic Classification

Rank	Coastal Silver-stiletto	Collared Petrel
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Arthropoda (Arthropods)	Chordata (Chordates)
Class	Insecta (Insects)	Aves (Birds)
Order	Diptera (Diptera)	Procellariiformes (Procellariiformes)
Family	Therevidae	Procellariidae
Genus	Acrosathe	Pterodroma
Species	Acrosathe annulata	Pterodroma brevipes

Evolutionary Relationship

Coastal Silver-stiletto and Collared Petrel share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Coastal Silver-stiletto

LC — Least Concern

Collared Petrel

VU — Vulnerable

Physical Characteristics

Attribute	Coastal Silver-stiletto	Collared Petrel
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Coastal Silver-stiletto

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

Collared Petrel

Habitat

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

Range

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

Coastal Silver-stiletto

Coastal silver stiletto (Acrosathe annulata) is a slender robber fly in the family Therevidae, native to northwestern Europe, including the United Kingdom, France, the Netherlands, Belgium, and Scandinavia. Adults are found on coastal sand dunes and sandy heathland, where they perch on bare sand to ambush small flying insects. Stiletto flies in the family Therevidae are characterised by a slender body, long pointed abdomen, and predatory habits; adults prey on a variety of small dipterans and other flying insects during warm, sunny periods. Larvae develop in sandy soil, where they are also predatory, feeding on other invertebrate larvae. Acrosathe annulata is a habitat specialist restricted to open, sandy coastal habitats with sparse vegetation—environments that have declined substantially across northwestern Europe due to dune stabilisation, recreational disturbance, and the cessation of traditional dune management. The IUCN lists it as Least Concern, though regional conservation bodies in the United Kingdom have flagged population declines. It is considered an indicator of high-quality coastal sand dune habitats and is monitored through national invertebrate surveys.

Collared Petrel

The Collared Petrel, known scientifically as <em>Pterodroma brevipes</em>, is a seabird belonging to the family Procellariidae, the petrels and shearwaters. <em>Pterodroma brevipes</em> is a gadfly petrel characterised by its typically dark upperparts contrasting with paler underparts, and by a distinctive collar or partial collar pattern on the breast and neck. The species is highly pelagic, spending much of its life at sea and returning to land only to breed on remote oceanic islands. It is reported to occur in Norway according to available range data. Like other gadfly petrels, <em>Pterodroma brevipes</em> is a dynamic flier, capable of soaring at speed in strong winds. Detailed biological traits including typical lifespan, body length, and weight are poorly documented for this species in available literature. The Collared Petrel is currently assessed as Vulnerable on the IUCN Red List, reflecting population concerns likely associated with threats at breeding colonies including introduced predators and habitat degradation.

Shared Countries

Both species can be found in 1 countries:

🇳🇴 Norway