Red Abalone (also known as Giant Abalone)
Phylum: Mollusca, Class: Gastropoda, Order: Vetigastropoda, Family: Haliotidae, Genus: Haliotis, Species: H. rufescens · Haliotidae (Abalone family) · Gastropod (univalve), whole shell, ear-shaped (auriform) spiral shape
Species
Haliotis rufescens
Shell Type
Gastropod (univalve), whole shell, ear-shaped (auriform) spiral shape
Family
Haliotidae (Abalone family)
Size
Approximately 5 to 7 inches, falling within the medium-large range for this species. Adults typically range from 6 to 10 inches, with maximum specimens reaching up to 12 inches.
Color & Pattern
The interior displayed here is brilliantly nacreous (mother-of-pearl) with iridescent flashes of pink, green, silver, and copper. The exterior (partially visible around the margins) is typically brick red to dull brownish-red with coarse growth lines.
Rarity
Uncommon to Rare depending on local regulations, conservation status, and strict limitations on harvesting wild specimens.
Habitat
Found in marine environments, specifically on rocky substrates in the low intertidal to shallow subtidal zones down to depths of about 50 feet, typically associated with giant kelp forests.
Geographic Range
Northeastern Pacific Ocean, ranging from the coast of Oregon down to Baja California, Mexico, with the highest concentrations along the coast of central and northern California.
Description
An exquisite specimen of an ear-shaped marine snail shell, featuring a broad, flat, low-spired profile with a cavernous interior. The interior showcases a mesmerizing mother-of-pearl sheen, punctuated by a series of open respiratory pores along the left margin. The muscular attachment scar is faintly visible, and the overall structure is robust and heavy.
Key Features
Distinguished by its large size, brick-red exterior, highly iridescent nacreous interior, and a row of typically 3 to 4 (sometimes up to 5) slightly elevated, open respiratory holes that flush water over the gills.
Collector Value
Moderately high, though commercial sale of wild-caught native California abalone is heavily regulated or restricted to protect populations. Prices vary widely based on size, polish, and legal provenance, ranging from $20 to over $100 for exceptional whole specimens.
Condition Notes
Good to Fine condition. The interior nacre is well-preserved with vibrant iridescence and minimal wear. The respiratory pores are intact, and the structure is solid with no major fractures, though minor edge chipping is present.
Interesting Facts
Abalone nacre is composed of microscopic calcium carbonate tiles glued together by organic proteins, making it exceptionally tough and impact-resistant. Indigenous peoples of the Pacific Coast historically used the shells for fishhooks, jewelry, and currency, and the meat is considered a high-end culinary delicacy.
Ecological Role
Red abalones are herbivorous grazers that feed primarily on drift kelp and algae, playing a key role in maintaining kelp forest ecosystems. They are prey for sea otters, large fish, and octopuses. Due to overfishing and disease, wild populations are closely monitored and strictly conserved.
Similar Species
Pink Abalone (Haliotis corrugata) which has a more heavily corrugated exterior surface, and Green Abalone (Haliotis fulgens) which features a dark interior nacre dominated by deep blue and green hues.
Beach Finding Tips
Finding a whole, intact abalone shell while casual beachcombing is quite rare due to their rocky subtidal habitat. They are more frequently discovered by divers or beachcombers following severe storms that dislodge shells from nearshore reefs.