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An initiative of Earthwatch Institute

  1. Ghost_crab1_steve_smith 3.75-5mm in size by S. Smith
  2. Image_2__dsc06913__2__d_shoeman Fresh Ghost Crab hole by D. Schoeman
  3. Ghost_crab_hole4_d_shoeman_banner Ghost Crab hole by D. Schoeman
  4. Ghost_crab_hole3_d_shoeman_banner Ghost Crab hole by D. Schoeman
  5. Ghost_crab_hole5_d_shoeman_banner Small Ghost Crab hole by D. Schoeman

Ghost Crab Holes

Ocypode sp.

Appearance

  • Ghost crabs comprise of a group of small- to medium-sized species shore crab.
  • Among ghost crabs, one claw is usually larger than the other, and their eyes are raised above their body on stalks, providing them with excellent vision. 
  • Active ghost crab holes are easily recognised by their size and the characteristic scattering of sand in the shape of a fan that broadens from the opening of the hole. The holes generally >20 mm, but very young crabs are known to make holes as small as 10 mm. Few other species make permenant burrows on beaches.
  • Size:  Holes 20 mm to 100 mm in diameter.
  • Ghost crabs are usually nocturnal, so count the abundance of fresh or active holes only. 
 

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

Ghost crabs generally live on relatively undisturbed beaches and their presence can indicate a healthy beach ecosystem.  Excessive foot traffic, vehicle use and removal of the kelp wrack through beach clean-ups, may disturb ghost crab habitats. Sea level rise may alter beach dynamics reducing available habitats that are suitable for ghost crabs. 

When To Look

Throughout the year

Where To Look

  • Common on oceanic beaches.  Usually nocturnal so rarely seen during the day.
  • On upper sections of the beach, above the strand line and along the first sand dune.
  • WA, NT, QLD, NSW
 

References

Davey, K. (1998). A Photographic Guide to Seashore Life of Australia. New Holland Publishers Australia Pty Ltd.

Edger, GJ. (2008). Australian Marine Life. The Plants and Animals of Temperate Waters [2nd Ed]. New Holland Publishers Australia Pty Ltd.

 

Links

  1. Search Species

  1. What Else?

    Ghost crabs look similar to the fiddler crabs (also Ocypodidae family) and solider crabs (Mictyris sp.) all of which can live in sandy environments. However both fiddler and solider crabs live only in estuarine environments and rarely found on oceanic beaches. 

    Ants can also make large holes in sand dunes, but tend to pile sand to all sides, rather than in a directional fan.

     

  1. Did You Know?

    Ghost crabs feed on carrion (dead animals) and seaweed (algae) washed up on the beach and have been known to eat turtle hatchlings.

    There are six different species of ghost crabs (genus Ocypode)  found in Australia and their burrows can be up to 200 metres from the shoreline and up to 1 metre deep. 

    The name Ocypode translates to ‘fast foot’ which it apt as the ghost crabs are one of the fastest animals on Earth for their size. They can run approximately 100 body lengths per second or around 7.5km/hr. If ghost crabs were the size of a human, that would equate to 400km/hr!