I subscribe to the 4 F's of bird photography; Find 'em and Focus Fast before they Fly away!
Saturday, August 20, 2011
A Crabby Day at Galapagos
As you land on any island from the sea, the first creature you are likely to see is Sally Lightfoot - a crab. Usually we don't think of crabs as beautiful, but this one certainly looks beautiful to me with all those bright colors! Her Latin name is Grapsus grapsus, which my mind read as Graspus graspus, an appropriate name for a crab that hangs on to the rocks when waves come pounding in, I thought.
The mature Sallys are bright red, and immediately visible against the black lava rocks, as they clamber around looking for bits of algae and other edible tidbits.
Youngsters are black as the lava itself, and hard to see until they move, giving them a better chance of survival.
Immature Sallys have spots - no, not crab acne, but a coloration advising other crabs that these aren't yet ready for mating, according to our guide Hanzel.
Hanzel found an unoccupied shell to show us one day. When the crab is ready to moult, it makes a foamy substance to separate its body from the old shell. Then it splits the old shell open, climbs out, and heads for the nearest rock until the new shell can harden. I always thought they would break the old shell into many pieces during this process, but apparently not.
From the right angle, they look like Samurai warriors!
According to seamen's lore, Sally Lightfoot was a night club dancer in the Caribbean. Although wearing hardly anything to cover her divine body, her dress was bright and colorful, red, orange and yellow. By profession, her movements were light and swift. A quick step sideways to avoid the odd hand snatching is her specialty. Easy to find, but hard to catch applies to both dancer and crab!
John Steinbeck said: "These little crabs, with brilliant cloissoné carapaces, walk on their tiptoes, They have remarkable eyes and an extremely fast reaction time. In spite of the fact that they swarm on the rocks at the Cape [Cabo San Lucas, Baja California], and to a lesser degree inside the Gulf, they are exceedingly hard to catch. They seem to be able to run in any one of four directions; but more than this, perhaps because of their rapid reaction time, they appear to read the mind of their hunter. They escape the long-handled net, anticipating from what direction it is coming. If you walk slowly, they move slowly ahead of you in droves. If you hurry, they hurry. When you plunge at them, they seem to disappear in little puffs of smoke – at any rate, they disappear. It is impossible to creep up on them. They are very beautiful, with clear brilliant colors, reds and blues and warm browns. We tried for a long time to catch them.”
When the ghost crabs cruise the beach, they put bits of sand in their mouths with their pincers, roll it around a bit for taste, then spit the inedible parts back out as little sand balls. The sharp tips of their legs leave a distinct trail of little holes in the sand.
Although Sally Lightfoot is the most common crab, we also found a semi-terrestrial hermit crab on Espanola. Poor thing, every time it moved to the edge of the rock trying to escape us, Hanzel moved it back to the top so we could get good photos. This guy's shell is getting small and he needs to start house hunting!
Watching this Sally move, you can understand by Steinbeck said they could move in all four directions!