Don't let their slow movement fool you, sea stars are an important part of rocky intertidal ecosystems. Some are fierce predators, while others are vital decomposers. Ochre sea stars in the genus *Pisaster* and sunflower sea stars in the genus *Pycnopodia* are considered to be keystone species because loss of these sea stars can lead to changes in community structure or function.

Map of Sites

An interactive map of Multi-Agency Rocky Intertidal Network (MARINe) sites within Olympic Coast National Marine Sanctuary (purple shading).

Interactive Trends - Ochre stars

Abundance ochre sea stars Pisaster ochraceus at six sites where rocky intertidal habitat has been monitored in Olympic Coast National Marine Sanctuary since 2007. Sea stars counts were averaged for all plots at each site each year. The bold, black line indicates the sanctuary-wide annual abundance calculated by averaging across the six sites each year. Source: Multi-Agency Rocky Intertidal Network (MARINe).

Trends - Size at Pt. Grenville

Size structure (radius from center of star to tip of arm in mm) of Pisaster ochraceus populations in rocky shore habitats at Point Grenville from 2008–2018. Size structure data are also available for Point of Arches, Kydikabbit, Taylor Point, and Starfish Point. Source: MARINe, 2019; Image: M. Miner/University of California, Santa Cruz.

Trends - Size at Sokol Point

Size structure (radius from center of star to tip of arm in mm) of Pisaster ochraceus populations in rocky shore habitats at Sokol Point from 2009–2018. Size structure data are also available for Point of Arches, Kydikabbit, Taylor Point, and Starfish Point. Source: MARINe, 2019; Image: M. Miner/University of California, Santa Cruz.