Sunflower sea stars are a critically endangered species of giant starfish native to marine waters along the Pacific Coast, from northern Baja California to the central Aleutian Islands. They can reproduce sexually through broadcast spawning, similar to that of some fish and coral species. The mating season occurs between March and July, with peak fertilization occurring in May and June.
Sunflower sea stars are oviparous, meaning they are born from eggs and engage in external reproduction. Sperm from the male fertilizes the female’s egg, which develops into bilateral, swimming larvae that live as plankton for no more than ten weeks. These larvae feed on zooplankton and metamorphose into planktonic forms that feed on single-celled plants. Both red and purple sea urchins, including the purple urchin, deploy their pedicellariae to nibble on the star’s tube feet. However, the red sea urchin has another defense – long spines.
The eggs develop into swimming, bilateral larvae that live as plankton for no more than 10 weeks. The larvae feed on single-celled plants when they settle on the bottom. Sunflower sea stars play a critical role in our marine ecosystem as natural predators of sea urchins, which are notorious for destroying kelp forests. However, sunflower sea star populations have declined, and researchers have been working with sperm in an aquarium lab to help them reproduce.
Sunflower sea stars can reproduce either asexually through fissiparity or sexually through broadcast spawning. They also have separate sexes and can be prepared by academy biologist Riah Evin. Successful spawning and cross-fertilization bring hope for the critically endangered sunflower sea star.
📹 Sunflower Seastar: Terrifying Predator? | National Geographic
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📹 Pacific Northwest scientists strive to save the sunflower sea star | Oregon Field Guide
The sunflower sea star once flourished along the West Coast, but in recent years the beautiful echinoderm has been dying in …
You’ll find these in cold water on the west coast of the U.S. I used to dive in Monterey Bay, CA, and would run into these beautiful star fish all the time. We would just call them “Sun Stars” for short. Also, that crab is called a Decorator Crab. They put organic material on their back, like barnacles, seaweed, and other plant life to camouflage. You can find more extraordinary sea life in cold water vs warm water in my opinion.
This is the type of work that makes me so happy to see in the Pacific Northwest. I hope we start seeing it all over to improve ecosystems & environmental health all over. This is the type of work people should be doing. The more our environment flourishes the more We flourish as well. Imagine how unhappy we would be if we negatively impacted most of our environments & we never did anything about it? A world with mostly people & very little natural biodiversity, sounds like a very unpleasant world. That’s why this work is really impactful.