Sunday, May 4, 2014

The Mangrove Tree Crab

Photographing from a canoe in south Florida allows me to capture various animals including the recently posted horseshoe crab. I've on occasion captured other types of crabs, such as this blue crab (see below) I found in Biscayne Bay. As I photographed it, it appeared to blow bubbles into the water. Quite interesting. Off the canoe I have also captured some land crabs, specifically inside the Fairchild Tropical Garden. The second image below is one of them.

The crabs that interest me the most are those that live among the mangrove trees. Where I see them mostly is when I paddle through the creeks of the Everglades or Biscayne Bay. There are two species of mangrove tree crabs that I am familiar with; the Goniopsis cruentata and the Aratus pisonii. The first of the two is the largest and most easily seen among the dark roots of the trees. Here's one that I happened to find one late summer day in a creek in Biscayne Bay. On that particular day, I spotted several of these red crabs and some appeared in twos. I have read that mating season for these crabs are during the rainy season, so there you have it in August.

As with any animal I photograph, I like to pay my respect by learning as much as I can about it. Recently, I was visiting friends in Sanibel and in the mangrove trees along the canal behind my friends' house were several Aratus pisonii types. Standing on land, I attempted to photograph them as the trees offered interesting surroundings and the lighting was nice. Once home, I did alittle research on these weird looking crabs.

First of all, I have to say they are not the most attractive subjects. But even more, they are very, very shy and they camouflage well. As my canoe moves through a creek, if I watch closely enough I can see several of them scuttling around a tree limb to get out of sight. In other words, they are not a frequently photographed subject. But since that day on Sanibel, I decided to learn about them and from this, they have become a more interesting and sought after subject.

This particular species of mangrove tree crabs are unique in that it is the only crab specie that does not breath air. Instead, it relies on water to cover its gills. Other interesting facts about this little crab is that it eats the surface of the mangrove leaves which causes scars or marks on the leaf. It also eats tiny animals and in turn, serves as food for the larger mangrove tree crab, like the red one shown above, and birds such as the white ibis. If the little crab falls into the water, mangrove snapper will snap them up. I also learned that mangrove tree crabs that survive without access to mangroves (such as on pilings) rely on algae for food and would not be able to survive if placed on a mangrove tree away from the pilings.

This summer as I explore the creeks, I will see many of these little creatures. I will look for them more keenly and attempt to photograph these interesting little creatures the best way possible. I will not pick one up and place it in a location where I might photograph it at my will. Instead, I will come to their habitat and patiently wait for the right opportunity. And yet another animal joins my list of favorite challenges.


  1. Third Photograph down . Land Crab. Hello my name is Deborah Rankin Matz. I am an Artist. I am requesting permission to paint the Land crab photo from your beautiful collection. Whenever I post or display my artwork ... I will always post you name and giving you the photography credit. Please go on my Facebook page. 1. Deborah Rankin Matz. 2. Then look for "Artwork By Deborah Rankin Matz". Then 3. go under "Photos" to view my Artwork. Please let me know. I appreciate your amazing photography and I am very respectful of your copyrighted materials.

  2. We were in St. Lucie County today and I was photographing some crabs which were not a species I was familiar with. A google search of Florida crabs did not help. Thanks to your post here I was able to determine that they were Mangrove Root Crabs.