Sand Dollar 7673160914 O
16Identifcation number on The Map®

Sand Dollar

Dendraster excentricus

Sand DollarFrederic Pache

Description

  • They are colored gray, brown, black or shades of purple
  • Their size is variable but up to 100 mm wide,and a dome shaped carapace varying in height to about 10 mm, with a circular body or test
  • Their body is covered with fine, spiny tube-like feet with cilia, and like other echinoderms they have five-fold radial symmetry

Range

  • It is the only sand dollar found in Oregon and Washington
  • It has been found on Burfoot Beach in the South Puget sound

Habitat

  • They are either found subtidally in bays or open coastal areas or in the low intertidal zone on sandy on the Northeast Pacific coast
  • It can live at a depth of 40 to 90 meters, but usually is found in more shallow areas
  • Sand dollars are usually crowded together over an area half buried in the sand
  • As many as 625 sand dollars can live in one square yard (0.85 sq m)

Diet

  • plankton

Interesting Facts

  • The habitat they live in on the sandy seafloor is sometimes damaged by bottom trawling, causing harm to many organisms
  • Ocean acidification and sea surface warming also harm populations of sand dollars