Sunflower stars are commonly found on various substrates like mud, sand, gravel, boulders and rock. They are found from the intertidal zone to 435 m, however, most are found no more than 120 m. (Lambert, 2000)
- Aquatic Biomes
- Other Habitat Features
- intertidal or littoral
- Range depth
- 435 (high) m
- 1427.17 (high) ft
- Sexual Dimorphism
- sexes alike
The eggs develop into swimming, bilateral larvae that usually remain in the plankton for no more than 10 weeks. The larval form feeds on single-celled plants. When the larva settles on the bottom it metamorphoses into a young sea star with five arms. The young (Alender, et al., 1966; Lambert, 2000)initially feeds on the thin layer skin-celled plants that coat the bottom of their marine habitat. The juvenille soon adds an arm clockwise from the bivium. Additional arms are added bilaterally in pairs to either side of the sixth ray. Each new pair is inserted between the last pair formed and the adjacent original arms.
- Development - Life Cycle
There is no sexual dimorphism within these species. Fertilization is external. (Lawrence, 1987)
- Mating System
- polygynandrous (promiscuous)
- Breeding interval
- Between March and July
There is no parental care within this species.
- Parental Investment
Sea stars have a life span usually between 3 and 5 years. ("Sea Stars", 2002)
- Typical lifespan
- 3 to 5 years
- Typical lifespan
- Average lifespan
- 3-5 years
- Average lifespan
Sunflower star have the ability to regenerate its arms which may detach as a means of defense when handled excessively or attacked by a predator. A whole new sea star may form if the detached arm has a portion of the central disk is included.
primarily moves by walking on its tube feet which possess suckers. This particular sea star can move more rapidly because of its flexible body and the aboral skeletal plates are loosely connected to one another.
Communication and Perception
If a predator attacks, (Lambert, 2000)can let its arm drop off and send a chemical that causes an alarm response to other sunflower stars in the area. If its arm is irritated or disturbed by a predator, it will drop it off or autotomize its arm. The autotomy is triggered by a chemical that is released by injured tissues. This allows sunflower stars to escape from the predator holding onto its arm.
- Communication Channels
- Other Communication Modes
- Primary Diet
- eats non-insect arthropods
- eats other marine invertebrates
- Animal Foods
- aquatic crustaceans
- other marine invertebrates
- Plant Foods
Economic Importance for Humans: Positive
There was no information regarding the economic importance ofto humans.
Economic Importance for Humans: Negative
This species is viewed by many commercial fishers as a pest. The results of the sunflower star's predacious behavior fouls long-line gear and crab pots. (Holmes, 1994)
Renee Sherman Mulcrone (editor).
Shayna Yagoda (author), University of Michigan-Ann Arbor, Phil Myers (editor), Museum of Zoology, University of Michigan-Ann Arbor.
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.
- 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.
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.
an animal that mainly eats meat
uses smells or other chemicals to communicate
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
union of egg and spermatozoan
An animal that eats mainly plants or parts of plants.
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.
- intertidal or littoral
the area of shoreline influenced mainly by the tides, between the highest and lowest reaches of the tide. An aquatic habitat.
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
eats mollusks, members of Phylum Mollusca
having the capacity to move from one place to another.
an animal that mainly eats all kinds of things, including plants and animals
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
chemicals released into air or water that are detected by and responded to by other animals of the same species
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
- radial symmetry
a form of body symmetry in which the parts of an animal are arranged concentrically around a central oral/aboral axis and more than one imaginary plane through this axis results in halves that are mirror-images of each other. Examples are cnidarians (Phylum Cnidaria, jellyfish, anemones, and corals).
- saltwater or marine
mainly lives in oceans, seas, or other bodies of salt water.
- 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).
uses sight to communicate
Tropica Beach. 2002. "Sea Stars" (On-line ). Accessed 03/25/03 at http://www.tropicabelize.com/Crab%20Collection/Crabs%20Photos/Sea%20Stars.htm.
Ahearn, G., R. Benhnke. 1991. Diet, Feeding-Behaviour, and Surface-Morphology of the Multiarmed Antartic Sea Star Labidiaster-Annulatus. Marine Ecology- Progress Series, 77/1: 65-84.
Alender, C., J. Anderson, J. Binyon, R. Boolootian, D. Davenport. 1966. Physiology of Echinodermata. New York: Interscience.
Dayton, P. 1975. Experimental Evaluation of Ecological Dominance in a Rocky Intertidal Algal Community. Ecological Monographs, 45/2: 137-159.
Duggins, D. 1983. Starfish Predation and the Creation of Mosaic Patterns in a Kelp-Dominated Community. Ecology, 64/6: 1610-1619.
Esquivel, C. 2003. "Critter Care Club-species list: Invertebrates" (On-line). Accessed December 08, 2004 at http://www.cabrilloaq.org/critter1.htm.
Holmes, P. 1994. "Star Fish" (On-line). Accessed December 09, 2004 at http://www.adfg.state.ak.us/pubs/notebook/shellfsh/starfish.php.
Lambert, P. 2000. Sea Stars of British Columbia, Southeast Alaska and Puget Sound. Vancouver: UBC Press.
Lawrence, J. 1987. A Functional Biology of Echinoderms. Baltimore: The John Hopkins University Press.
Wootton, J. T. 1997. Estimates and Tests of Per Capita Interaction Strength: Diet, Abundance, and Impact of Intertidially Foraging Birds. Ecological Monographs, 67/1: 45-64.