An initiative of Earthwatch Institute

  1. White_tip_steve_smith White tipped Urchin by S Smith
  2. White_tip2_graham_edgar Body width 4-16cm and spine length max 3cm by S Smith

White-tipped Urchin

Echinometra mathaei


  • Greenish-grey or reddish-brown to black in coloured
  • Short and thick spines white to pale white in colour, often have a white circle at their base
  • When viewed from above, white tipped urchins are slightly oval in shape 
  • Size: body width 4-16cm, spine length up to 3cm.

What to Observe

Search area for 30 minutes and record under the following categories-

  • Abundant - found easily with little searching
  • Frequent - found with minimal searching
  • Rare -  only 1 or 2 individuals found with intensive searching
  • Not found - not present during search

ClimateWatch Science Advisor

As a result of climate change, warm tropical ocean currents are expected to strengthen and persist for longer periods in southern coastal area normally dominated by cooler waters. The consequent increases in water temperature are likely to result in unfavourable conditions for sea urchin species. Climate change may also alter the chemical properties of sea water, making it harder for urchins to grow and reproduce. 

When To Look

Throughout the year

Where To Look

  • These sea urchins require a secure surface to attach themselves to in order to resist wave and tide action. Commonly found on rocks and coral crevices in rock pools. They can also bore into hard rock and coral to make a home for themselves.
  • Tropical Australia to mid NSW and Esperance WA. Also on Lord Howe Island
  • QLD, WA, NSW

  1. Search Species

  1. What Else?

    There are several other urchin species in the same family (Temnopleuridae) that have short or soft looking spines and look similar to the hairy sea urchin (T.  gratilla), however, these are normally difficult to find (being cryptic), and live mainly in the curled fronds of kelp. The hairy sea urchin can be distinguished from most of these by its common behaviour of collecting algae, pebbles and shell fragments and placing these on its body (hence their other name, collector sea urchins).  

  1. Did You Know?

    Spines contain poison that can be painful to humans.

    These are a nocturnal species that hide in crevices during the day and come out tho feed on algae, sea grasses and organic matter during the night.

    Their main predators are puffer fish, trigger fish and humans despite their poisonous sharp spines.

    Overfishing has dramatically reduced their populations.

    The species name originally came from the old English word meaning Spiny hedgehog.