The white abalone,
scientific name ''Haliotis sorenseni'', is a
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of large
sea snail, a
marine gastropod mollusk
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...
in the
family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
Haliotidae
''Haliotis'', common name abalone, is the only genus in the family Haliotidae.
This genus once contained six subgenera. These subgenera have become alternate representations of ''Haliotis''. The genus consists of small to very large, edible, ...
, the abalones.
[Rosenberg, G. (2014). Haliotis sorenseni. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=445362 on 2014-10-29]
The white abalone is an endangered species in the United States; it may now have the smallest population of all eight of the abalone species on the west coast of North America.
Distribution
![White abalone range](https://upload.wikimedia.org/wikipedia/commons/a/a0/White_abalone_range.jpg)
Historically the white abalone ranged from
Point Conception
Point Conception (Chumash: ''Humqaq'') is a headland along the Gaviota Coast in southwestern Santa Barbara County, California. It is the point where the Santa Barbara Channel meets the Pacific Ocean, and as the corner between the mostly north ...
,
California
California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...
to
Baja California
Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...
,
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
, and was found especially on the offshore islands.
In the most northerly part of the
California
California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...
range, white abalone were reported as being more common along the mainland coast. However, in the middle portion of the California range, they were noted to occur more frequently at the offshore islands, especially
San Clemente
San Clemente (; Spanish for " St. Clement") is a city in Orange County, California. Located in the Orange Coast region of the South Coast of California, San Clemente's population was 64,293 in at the 2020 census. Situated roughly midway between ...
and
Santa Catalina Islands. At the more southerly end of the range, in Baja California, Mexico, white abalone were reported to occur more commonly along the mainland coast, but were also found at a number of islands including
Isla Cedros
Cedros Island (''Isla de Cedros'', "island of cedars" in Spanish) is an island in the Pacific Ocean belonging to the state of Baja California, Mexico. The dry and rocky island had a population of 1,350 in 2005 and has an area of which includes ...
and
Isla Natividad
Isla Natividad is an island in the Pacific Ocean 6 km west off Punta Eugenia, the northwestern headland of the Mexican state of Baja California Sur. 200 meters off its northwestern end lies Roca María at , with an area of 0.074 km2 ...
.
It remains unknown whether this distribution pattern was a result of lack of suitable habitat along the mainland coast in the mid portion of the range, or was instead due to overfishing in these more accessible mainland regions.
Since the mid-1990s, extremely low numbers of isolated survivors have been identified along the mainland coast in
Santa Barbara County
Santa Barbara County, California, officially the County of Santa Barbara, is located in Southern California. As of the 2020 census, the population was 448,229. The county seat is Santa Barbara, and the largest city is Santa Maria.
Santa Barba ...
and at some of the offshore islands and banks in the middle portion of the range, indicating the current range of white abalone in California may be similar to what it was historically.
No recent information on current range is available for Baja California. The white abalone population in Mexico is thought to be depleted based on commercial fishery data, but the status of the species in Mexico remains largely unknown.
Description
Shell
The white abalone usually has between 3-5 open holes (respiratory pores) in its
shell
Shell may refer to:
Architecture and design
* Shell (structure), a thin structure
** Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses
** Thin-shell structure
Science Biology
* Seashell, a hard o ...
. These holes collectively make up what is known as the
selenizone
A selenizone (from the Greek "selene" meaning "moon", and "zone" meaning "girdle") is an anatomical structure that exists in the shells of some families of living sea snails: the slit shells, the little slit shells and the abalones, which are ...
which form as the shell grows. The shell is oval-shaped, very thin and deep. White abalone can grow to about , but are usually .
Anatomy
The epipodial tentacles are lacy, beige and yellow-green in color. The bottom of its foot is orange, and the epipodium (a sensory structure and extension of the foot that bears tentacles) is a mottled orange tan.
Ecology
Habitat
The white abalone is the deepest dwelling of eight species of California abalones, living at depths from .
White abalone are found in open low and high relief rock or boulder habitat that is interspersed with sand channels. Sand channels may be important for the movement and concentration of drift
macroalgae
Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of '' Rhodophyta'' (red), ''Phaeophyta'' (brown) and ''Chlorophyta'' (green) macroalgae. Seaweed species such as ...
, and a variety of red
algae, upon which white abalone are known to feed.
Feeding habits
The white abalone is known to be a
herbivore, grazing mainly on
macroalgae
Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of '' Rhodophyta'' (red), ''Phaeophyta'' (brown) and ''Chlorophyta'' (green) macroalgae. Seaweed species such as ...
, such as ''
Laminaria farlowii'' and ''
Agarum fimbriatum'', and also several species of
red algae.
Other species it eats include ''
Chondracanthus exasperatus'', ''
Laminaria farlowii'', ''
Macrocystis pyrifera '', and ''
Palmaria mollis Palmaria may refer to:
* Palmaria (island), an island in the Ligurian Sea, Italy
* Palmaria (artillery), an Italian-made self-propelled howitzer
* ''Palmaria'' (alga), a genus of red algae
**'' Palmaria palmata'', a species of red algae
{{disamb
...
''.
Life cycle
Like many gastropods, white abalone have a complex
life cycle
Life cycle, life-cycle, or lifecycle may refer to:
Science and academia
*Biological life cycle, the sequence of life stages that an organism undergoes from birth to reproduction ending with the production of the offspring
* Life-cycle hypothesis ...
involving
larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle.
...
l stages.
Fertilized
Fertilisation or fertilization (see spelling differences), also known as generative fertilisation, syngamy and impregnation, is the fusion of gametes to give rise to a new individual organism or offspring and initiate its development. Proce ...
eggs hatch into larvae; these larvae eventually
metamorphose
Metamorphosis is a biological process by which an animal physically develops including birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some insec ...
into the adult form and settle from the
plankton
Plankton are the diverse collection of organisms found in water (or air) that are unable to propel themselves against a current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucia ...
to a hard
substrate.
As broadcast
spawning
Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of releasing the eggs and sperm, and the act of both sexes is called spawning. Most aquatic animals, except for aquat ...
gastropods, white abalone reproduce by releasing their eggs and
sperm into the surrounding water. If fertilized, the eggs hatch after only one day, but high concentrations of sperm are required in order for an egg to be fertilized. Therefore, aggregations of adult male and female abalone are necessary for successful fertilization to occur.
Human use
Scripps Institution of Oceanography biologists conducted surveys of white abalone deep water habitat in the early 1970s, finding high concentrations of about one white abalone per square yard. Such densities were comparable to abundance of shallower species of abalone found in previously unfished or protected areas. Unfortunately, the high demand for the species led to a "boom-and-bust" fishery, which decimated the populations of this species in seven years.
Considered a
delicacy
A delicacy is usually a rare and expensive food item that is considered highly desirable, sophisticated, or peculiarly distinctive within a given culture. Irrespective of local preferences, such a label is typically pervasive throughout a r ...
in California, white abalones, the rarest of the six abalone species in the state, have declined by over 99.99% due to increasing
overfishing, in part illegal – the fishery was closed in 1996 – while at the same time, prices have escalated. Although white abalones were the first marine invertebrate on the
United States Federal List of Endangered Species in 2001, the species could nevertheless become extinct unless extraordinary recovery measures are implemented.
White abalone is being
maricultured in order to produce young that can be placed back in the ocean, in hopes of bringing this species back to secure population levels before it becomes extinct. The White Abalone Restoration Consortium is a partnership with The Cultured Abalone Farm, the
Santa Barbara Museum of Natural History Sea Center
The Santa Barbara Museum of Natural History Sea Center, briefly known as the Ty Warner Sea Center, is a museum owned and operated by the Santa Barbara Museum of Natural History and is located on Santa Barbara's Stearns Wharf. The Sea Center focuse ...
and the National Oceanic and Atmospheric Administration Southwest Fisheries Science Center on the
Gaviota Coast
The Gaviota Coast in Santa Barbara County, California is a rural coastline along the Santa Barbara Channel roughly bounded by the city of Goleta, California, Goleta on the south and the north boundary of the county on the north. This last undeve ...
which is studying the marine snail and restoring the wild populations. They are also collaborating in developing curriculum to educate the next generation about sustainable
aquaculture and
conservation
Conservation is the preservation or efficient use of resources, or the conservation of various quantities under physical laws.
Conservation may also refer to:
Environment and natural resources
* Nature conservation, the protection and managem ...
.
References
;Sources
*This article incorporates public domain text (a
public domain
The public domain (PD) consists of all the creative work to which no exclusive intellectual property rights apply. Those rights may have expired, been forfeited, expressly waived, or may be inapplicable. Because those rights have expired, ...
work of the United States Government
A work of the United States government, is defined by the United States copyright law, as "a work prepared by an officer or employee of the United States Government as part of that person's official duties." "A 'work of the United States Governmen ...
) from reference
and CC-BY-2.5 text from reference
[Courchamp F., Angulo E., Rivalan P., Hall R. J., Signoret L., Bull L. & Meinard Y. (2006) "Rarity Value and Species Extinction: The Anthropogenic Allee Effect". ''PLoS Biology'' 4(12): e415. ]
Team Spawns Rare White Abalone
;Notes
External links
"Race To Save the White Abalone" video links(NOAA Southwest Fisheries Science Center)
White Abalone Research(NOAA Southwest Fisheries Science Center)
*
National Marine Fisheries Service
The National Marine Fisheries Service (NMFS), informally known as NOAA Fisheries, is a United States federal agency within the U.S. Department of Commerce's National Oceanic and Atmospheric Administration (NOAA) that is responsible for the ste ...
. (October 2008). "White Abalone Recovery Plan (''Haliotis sorenseni'')". National Marine Fisheries Service, Long Beach, CA
PDFSonoma County Abalone Network*
{{Authority control
sorenseni
Endangered fauna of California
Gastropods described in 1940