Blueberry hermit crabs are commonly found on local beaches in Okinawa. Most crabs are blue but occasionally have color variations of purple, pink, orange and or gray. They prefer to have a seashell as a protective home but when no shell is available they adapt.
Before plastic caps filled our shorelines, hermit crabs adapted using tree nuts if no shells were available.
It’s becoming more common to find crabs with beach trash homes. I have friends combing local beaches in search of more crabs for my series. While these are cute images, our trash is becoming a serious problem to the ocean and the animals that call the shoreline home. I often find hermit crabs using a variety of plastic caps from twist top pet bottles, laundry detergent containers, small propane tanks, sports water bottles and beauty supplies.
- Limited number of available shells causing them to make due with the best homes they can find. This is a good example of adaptive behavior.
Hermit crabs are very social animals and often fight over shells. Having a protective lightweight shell that covers the abdomen (soft parts of the animal) is crucial for survival.
A close-up of the sensitive abdomen (photographed using the MYN technique)
Hermit crabs are scavengers and take advantage of any food washed ashore. They mainly feed on dead fish, barnacles, other crabs, algae, insects, plants, fruit and various seeds. The screw pine (Pandanus odifer) is one of their favorite foods. I imagine long ago these vital plants lined our shorelines in abundance. Numbers are decreasing due to deforestation.
Eventually the fruit drops to the ground and the sweet smell attracts the hermit crabs
The hermit crabs feed on the the fresh keys and help with seed dispersal. They both benefit in this relationship. The Pandanus tree provides shelter, shade, food for the hermit crabs.
Eventually the keys dry, turn brown and litter the local beaches. The dispersed keys provide a perfect environment for hermit crabs to blend in with.
Hermit crabs prefer to be in a shell that protects the entire body from predators. Sometimes they have to temporarily adapt with a much smaller shell. The retracted hermit crab tightens up to protect itself. Ball up, play dead and blend into the environment, minimizing the risk of being preyed upon.
Could this be a form of masquerading or just coincidence ? It resembles (mimics) the shape of the screw pine seed to possibly avoid detection from potential predators.
Hermit crabs have the ability to ball up tight to protect their eyes. (Transformers)
Below are some of my favorite images photographed on a portable field studio board (MYN Technique). The crabs are safely placed on a white studio board, photographed and released back into the natural environment (MYN Technique).
It’s important to photograph the hermit crabs in their natural habitat. I prefer to photograph them using a wide angle lens to achieve a unique perspective.
I also photograph the hermit crabs using a dedicated macro lens. I mainly use the Canon 60 mm or 100 mm macro lens to concentrate on the subject. These crabs are fairly small and it’s important to have a lens that will focus close and deliver high quality sharpness.
School project ” Crabs with beach trash homes ” My family and I collected trash on a local beach in Onna village. This is just a small portion of our beach trash findings. The kids did a great job creating a project with impact.
Behind the scenes photograph ” Crabs with beach trash homes ” I have documented over sixty crabs with beach trash homes. If you would like to see more images check out my Flickr account.
June 10th 2010 was my first experience seeing a hermit crab with a trash home.
My series ” Crabs with beach trash homes ” has been featured on World Wildlife Fund, Petapixel, Business Insider, National Geographic (Belgium), Atlas Obscura, Global citizen, Plethorist, Daily telegraph, Littlethings, 15minutenews, Roaring earth, Hyperdojo, News.com.au, Follownews, Neotorama, Boingboing, Insider, Additivist, Now100fm and varies Scientific websites.
Our trash is becoming a serous problem on our shorelines! Let’s keep our shorelines clean!
Have a great day!