Gigantic Hermit Crabs Found On Okinawa

Last year, a friend and I stumbled upon a local beach with gigantic hermit crabs. All of the hermit crabs were found adapting with non-native seashells.

Indonesian hermit crab (Coenbita brevimanus)

Indonesian hermit crab (Coenbita brevimanus)

Where did these shells come from?  The shell shack

The shell shack is an old wooden shed filled with boxes of imported craft shells from the Philippines. The hermit crabs found an opening and took advantage of this real estate.

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Polished muffin (Ryssota ovum)

The most abundant shell was the polished muffin (Ryssota ovum) land snail. This shell is native to the Philippines and is twice the size of any land snail on Okinawa. The muffin shell is a perfect mobile home for the land hermit crabs. It’s lightweight, durable and large.

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perspective photograph

The hermit crabs were healthy and doing well. I didn’t see any hermit crabs adapting with plastic or any twist top caps.

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Land hermit crab (Coenobita cavipes)

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Land hermit crab (Coenobita cavipes)

I also found hermit crabs adapting with a variety of marine shells from the Philippines at the same location.

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Babylonia arealata (Coenobita purpureus)

hermit crab

hexaplex cichoreum (Coenobita cavipes)

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Volema carinifera (Coenobita cavipes)

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Melanella candida (Coenobita purpureus)

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Casmaria erinaceus (Coenobita purpureus)

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hexaplex cichoreum (Coenobita purpureus)

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Turbo chrysostomus (Coenobita purpureus)

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Tonna sulcosa (Coenobita cavipes)

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Learn more about hermit crabs and adaptive behavior ” Crabs with beach trash homes

My Mission: To Protect and Preserve the Wildlife of the Ryukyu Islands for Future Generations. – If you would like to join my journey, check out my Patreon https://www.patreon.com/MakeTheSwitch4Nature

Your donations will help conservation initiatives as well as bring solutions to the worldwide pollution issues on our beautiful shorelines.  Thank you for your support, Shawn M Miller.

#MakeTheSwitch4Nature

Searching for the Ryukyu Ghost Crab by Shawn Miller

Ghost crabs are one of the fastest terrestrial crabs on the planet. They live in burrows underneath the sand on the coastline. They are found scavenging for food early in the morning and late in the evening to avoid predators. These sand crabs can change colors to adapt to their environment.  In Okinawa, we have two species of Ghost crabs,  the Horn-eyed crab (Ocypode ceratophthalmus) and the Smooth-eyed ghost crab (Ocypode cordimanus).

Horn-eyed ghost crab at sunset

Horn-eyed ghost crab at Maede flats

Ghost crabs have three ways to avoid predators.

  1. Stay close to their burrow and retreat into it quickly.
  2. Escape into the surf zone and burrow underneath the wet sand.
  3. Stay still and slowly dig into the beach sand
Ghost crab burrow

Ghost crab burrow

Ryukyu Horn-eyed ghost crab

Elusive ghost crab

These crabs have the ability to fold their eyes into grooves for protection.

Ghost crab - Fill flash and back-lighting Stella 200

Ghost crab & Stella 2000

This large ghost crab tried to intimidate me with its large claws and scary shadow.

The sand dwelling hunter

The sand dwelling hunter

These crabs were photographed on white for the Meet Your Neighbours Biodiversity Project. The project is dedicated to connecting people worldwide with the wildlife in their communities.  All images are used for conservation awareness and educational purposes.

MYN Biodiversity Project Japan

MYN Biodiversity Project Japan.

Juvenile ghost crab

Juvenile – Ocypode sp

The Juveniles can be extremely colorful depending on their surrounding environment. I have been finding more and more trash washed on the shoreline.  Could the crabs possibly be adapting to the colors of the sounding marine debris washed ashore?

the Smooth-eyed ghost crab ( Ocypode cordimanus)

the Smooth-eyed ghost crab ( Ocypode cordimanus)

All ghost crabs are scavengers, mainly feeding on seaweed, fruit, seeds, other crabs, turtle hatchlings, and insects.

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feeding on beetles

Feeding on a hermit crab

Feeding on a hermit crab

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Feeding on a shrew

These crabs are beautiful creatures and hopefully, you will get the opportunity to see one in the wild.

Pink ghost crab

Pink ghost crab

People often ask me what is the purpose of conservation photography? Having the ability to affect some form of positive change in the environment and make a global difference with the photographs. Hopefully, the images will inspire people to care more about nature and make a positive difference in the environment.

 

 My Mission: To Document and Preserve the Wildlife of the Ryukyu Islands

This site is also designed to help people identify the beautiful animals of Okinawa, basically to serve as an online nature reference guide. If you would like to make a contribution to support my mission, please click on the donation link  paypal.me/maketheswitch4nature

Your donations will help conservation initiatives as well as bring solutions to the worldwide pollution issues on our beautiful shorelines.  Thank you for your support, Shawn M Miller.

#MakeTheSwitch4Nature