Panulirus interruptusCalifornia spiny lobster

Geographic Range

California spiny lobsters are found on the Pacific coast of North America from Monterey Bay, California (though rarely found north of Point Conception) to Baja California, Mexico. They are occasionally found within the Gulf of California. ("Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Southwest): Spiny Lobster", 1988; Holthuis, 1991)


California spiny lobsters prefer rocky reef habitats, where they den in crevices. They occasionally are found in tide pools, but are more frequently found in deeper water up to 65 m in depth. California spiny lobsters seek the cover of kelp forests and surf grass. (Holthuis, 1991; Hovel and Lowe, 2007)

  • Range depth
    65 (high) m
    213.25 (high) ft

Physical Description

California spiny lobsters average 908 g in mass and range from 454 to 2270 g. On average, they are 30 cm long, though they can measure as large as 90 cm in length. Males are generally larger than females. The body of California spiny lobsters consists of a cephalothorax, which includes the head and legs, and an abdomen and tail, which has paddle-like swimming structures. The exoskeleton is generally red to orange in color with black markings. Spiny projections are located on the carapace (upper shell) and sides of the abdomen. Their two primary antennae may equal the length of their body. Their compound eyes rest on short stalks protected by curved spines. Unlike Maine lobsters in which the first pair of thoracic appendages are specially modified as chelipds (claws), all five pairs of appendages of California spiny lobsters are used for walking. (California Sea Grant, 2008; Holthuis, 1991)

  • Sexual Dimorphism
  • male larger
  • Range mass
    454 to 2270 g
    16.00 to 80.00 oz
  • Average mass
    908 g
    32.00 oz
  • Range length
    90 (high) cm
    35.43 (high) in
  • Average length
    30 cm
    11.81 in


Female California spiny lobsters produce between 50,000 and 800,000 eggs per brood, which are carried underneath the abdomen by pleopods until they hatch. After hatching, young are released into the water column as phyllosoma larvae. California spiny lobsters undergo 11 distinct phyllosoma stages. They range in size from 1.2 to 1.5 mm in Stage I and from 26 to 31.2 mm in Stage XI. During these stages, they are completely planktonic, drifting with water currents. This is the most hazardous part of the life cycle. After growth and development in the water column, larvae metamorphose into puerulus, assuming the body characteristics of the adult. Puerulus settle to the seafloor and grow into juvenile lobsters. (Lindberg, 1955)


Mating of California spiny lobsters generally begins under moderate sea surface temperatures, usually during upwelling conditions. Mating takes place in water 15 to 30 m deep from December through March. During copulation, male California spiny lobsters deposit spermatophores on the sternum of a female. Females then move inshore to shallow water (usually less than 15 m in depth) and extrude 50,000 to 800,000 eggs. These eggs are fertilized by sperm released from the spermatophores, and they attach in masses to feathery pleopods beneath the abdomen of females. ("Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Southwest): Spiny Lobster", 1988; Diaz-Arrendondo and Guzman, 1995)

Mature California spiny lobsters mate between December and March and spawn between March and August. Spawning occurs once a year and reproduction peaks in June. Females produce 50,000 to 800,000 eggs with each brood. Females reach sexual maturity at 5 to 9 years of age, while males reach sexual maturity at 3 to 6 years of age. ("Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Southwest): Spiny Lobster", 1988; Diaz-Arrendondo and Guzman, 1995)

  • Breeding interval
    California spiny lobsters breed once a year during warmer months.
  • Breeding season
    California spiny lobsters spawn between March and August.
  • Range number of offspring
    50,000 to 800,000
  • Range age at sexual or reproductive maturity (female)
    5 to 9 years
  • Range age at sexual or reproductive maturity (male)
    3 to 6 years

After spawning in late spring, female California spiny lobsters hold their fertilized eggs in their abdomen until they hatch. Females have feathery appendages that carefully hold the eggs as well as small pincers on the fifth pair of walking legs used to groom and maintain the egg mass. (Lindberg, 1955)


Lifespan of California spiny lobsters is difficult to determine because their exoskeleton is periodically molted. Individuals in the wild have been known to live between 11 and 30 years, while in captivity they have survived 8 to 25 years. ("Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Southwest): Spiny Lobster", 1988)

  • Range lifespan
    Status: wild
    11 to 30 years
  • Range lifespan
    Status: captivity
    8 to 25 years


California spiny lobsters are nocturnal, hiding in crevices and dens during the day to avoid predators. They are semi-social, sharing dens with conspecifics. At night, spiny lobsters emerge to forage, traveling up to 600 m in search of food. (Case, et al., 1985; Diaz-Arrendondo and Guzman, 1995)

Home Range

California spiny lobster constantly moves from place to place, resting in a den during the day and traveling to find food at night. They have been known to travel up to 600 m in search of food. It is unclear whether California spiny lobsters return to the same den. (Case, et al., 1985)

Communication and Perception

California spiny lobsters use visual sensing to detect predators, and chemical stimuli are perceived through the small antennae. Sensory hairs cover their appendages, including the long antennae, which are used for tactile perception. They also rub the base of their antennae against a file-like surface under each eye to generate strident warning noises to scare off potential predators. (Lindberg, 1955; Staaterman, et al., 2009)

Food Habits

California spiny lobsters are omnivorous bottom feeders that scavenge dead animals, algae, and detritus. They also consume invertebrates such as the species of mussel Mytilus californianus and urchins Strongylocentrotus franciscanus and S. purpuratus. California spiny lobsters use their mandibles to chip away at the shells of M. californianus In the winter, California spiny lobsters occasionally eat coralline algae. Their diet varies seasonally, and males generally consume a wider variety of prey than females. (Case, et al., 1985; Diaz-Arrendondo and Guzman, 1995; Eminike, et al., 1990; Lindberg, 1955)

  • Animal Foods
  • fish
  • carrion
  • mollusks
  • aquatic or marine worms
  • aquatic crustaceans
  • echinoderms
  • other marine invertebrates


To ward off predators, California spiny lobsters produce rasping noises by stridulating the base of the antennae against a file-like eyespot. They also attempt to flee, swimming backwards by repeatedly and rapidly flexing their abdomen. If caught by a predator, decopods self-autotomize (purposely cast off an appendage) to escape. California spiny lobsters are preyed upon by octopuses, California sheephead, cabezon, kelp bass, California moray eels, horn sharks, leopard sharks, giant sea bass, and various rockfish. Humans also fish for California spiny lobsters. (Barsky, et al., 2003; Lindberg, 1955; Staaterman, et al., 2009)

Ecosystem Roles

California spiny lobsters are important coastal nearshore predators that have been shown to regulate the population of several key invertebrate species such as purple urchins and the mussel species Mytilus californianus. They also act as hosts to sponges, hydroids, barnacles, serpulida, krill-like amphipods and nemertean (Carcinonemertes wickhami). (Eminike, et al., 1990; Lafferty, 2004; Lindberg, 1955)

Commensal/Parasitic Species

Economic Importance for Humans: Positive

California spiny lobsters have supported recreational and commercial fishing in Southern California since the late 1800s. From 1916 until 1942, annual commercial landings ranged between 90 to 180 metric tons, and in 2003 over 270 metric tons were harvested. The magnitude and impact of the recreational fishing for this species is unknown. (Barsky, et al., 2003)

  • Positive Impacts
  • food

Economic Importance for Humans: Negative

There are no known adverse effects of California spiny lobsters, although their spiny carapace can cut an unprotected hand of sport fishermen.

  • Negative Impacts
  • injures humans

Conservation Status

California spiny lobsters have not been evaluated by the IUCN or the US Fish and Wildlife Service. However, fishing removes considerable numbers of this species which may not be sustainable.


Natalie Craig (author), San Diego Mesa College, Hannah Fabares (author), San Diego Mesa College, Thomas Kukula (author), San Diego Mesa College, Gabe Shipley (author), San Diego Mesa College, Paul Detwiler (editor), San Diego Mesa College, Gail McCormick (editor), Animal Diversity Web Staff.



living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

Pacific Ocean

body of water between the southern ocean (above 60 degrees south latitude), Australia, Asia, and the western hemisphere. This is the world's largest ocean, covering about 28% of the world's surface.

World Map


uses sound to communicate


having coloration that serves a protective function for the animal, usually used to refer to animals with colors that warn predators of their toxicity. For example: animals with bright red or yellow coloration are often toxic or distasteful.


Referring to an animal that lives on or near the bottom of a body of water. Also an aquatic biome consisting of the ocean bottom below the pelagic and coastal zones. Bottom habitats in the very deepest oceans (below 9000 m) are sometimes referred to as the abyssal zone. see also oceanic vent.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.


an animal that mainly eats meat


flesh of dead animals.


uses smells or other chemicals to communicate


the nearshore aquatic habitats near a coast, or shoreline.


having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.


an animal that mainly eats decomposed plants and/or animals


particles of organic material from dead and decomposing organisms. Detritus is the result of the activity of decomposers (organisms that decompose organic material).


animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature

external fertilization

fertilization takes place outside the female's body

female parental care

parental care is carried out by females


union of egg and spermatozoan


A substance that provides both nutrients and energy to a living thing.


having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.

indeterminate growth

Animals with indeterminate growth continue to grow throughout their lives.

intertidal or littoral

the area of shoreline influenced mainly by the tides, between the highest and lowest reaches of the tide. An aquatic habitat.


offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).


seaweed. Algae that are large and photosynthetic.


A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.


makes seasonal movements between breeding and wintering grounds


having the capacity to move from one place to another.


specialized for swimming

native range

the area in which the animal is naturally found, the region in which it is endemic.


active during the night


reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

saltwater or marine

mainly lives in oceans, seas, or other bodies of salt water.


an animal that mainly eats dead animals

seasonal breeding

breeding is confined to a particular season


reproduction that includes combining the genetic contribution of two individuals, a male and a female


uses touch to communicate


that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).


movements of a hard surface that are produced by animals as signals to others


uses sight to communicate


U.S. Fish and Wildlife Service. Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Southwest): Spiny Lobster. Biological Report 82 (11.47). Washington, DC: U.S. Department of the Interior. 1988. Accessed May 28, 2010 at

Barsky, K., A. Vejar, C. Ryan. 2003. "Annual status of the fisheries report through 2003: California spiny lobster" (On-line). Accessed May 02, 2010 at

California Sea Grant, 2008. "California Spiny Lobster: fishing and life history information" (On-line). Accessed April 02, 2010 at

Case, J., R. Zimmer-faust. 1982. Odors influencing foraging behavior of the California spiny lobster, Panulirus interruptus, and other decapod crustacea. Marine Behavior and Physiology, 9(1): 35-58.

Case, J., J. Tyre, R. Zimmer-Faust. 1985. Chemical attraction causing aggregation in the spiny lobster, Panulirus interruptus (Randall), and its probable ecological significance. Biological Bulletin, 169: 106-118.

Diaz-Arrendondo, M., S. Guzman. 1995. Feeding habits of the spiny lobster (Panulirus interruptus Randall 1840) in Bahia Tortugas, Baja California Sur. Ciencias Marinas, 21(4): 439-462.

Eminike, J., D. Sweetnam, C. Robles. 1990. Lobster predation on mussels: shore-level differences in prey vulnerability and predator preference. Ecology, 71(4): 1564-1577.

Holthuis, L. 1991. "Vol.13. Marine Lobsters of the World: An annotated and illustrated catalogue of marine lobsters known to date" (On-line pdf). Accessed April 05, 2010 at

Hovel, K., C. Lowe. 2007. "Shelter use, movement and home range of spiny lobsters in San Diego County" (On-line pdf). Accessed April 05, 2010 at

Lafferty, K. 2004. Fishing for lobsters indirectly increases epidemics in sea urchins. Ecological Applications, 14/5: 1566-1573. Accessed May 02, 2010 at

Lindberg, R. 1955. Growth, population dynamics and field behavior in the spiny lobster, Panulirus interruptus (Randall). University of California Press Berkeley and Los Angeles, 59: 157-247.

Shields, J., A. Kurls. 1989. Carcinonemertes wickhami n. sp. (NemerteaJ, a symbiotic egg predator from the spiny lobster Panulirus interruptus in Southern California, with remarks on symbiont-host adaptations. Fishery Bulletin, 88: 279-287. Accessed June 02, 2010 at

Staaterman, E., T. Claverie, S. Patek. 2009. Disentangling defense: the function of spiny lobster sounds. Behaviour, 147: 235-258. Accessed June 02, 2010 at,%202009.pdf.

Velaquez, A. 2003. Reproductive strategies of the spiny lobster, Panulirus interruptus, related to the marine environmental variability off central Baja California Mexico: management implications. Fisheries Research, 65(1-3): 123-135.