For certain, St. Thomas has more one lane roads than it has one-way streets. The scene being played out by these whelks and crab perfectly mimics the car driving experience on “The Rock”.

For non-islanders: “The Rock” is “Rock City”, the nickname we gave St. Thomas. Everywhere you look on St. Thomas there are rocks. And not just any rocks – some of the hardest granite on the planet – Blue-Bitch. If I give you a pick axe and shovel and ask for a ten foot trench, three feet deep and three feet wide, I will check in on you in a week to see how the project is going. Yeah, it’s like that!

Back to our crab and whelks jam. What exactly are they doing? 

I can hazard a guess if you can forgive any blatant anthropomorphizing. Just guessing here:

Both are algae eaters competing for the same nutrient laden rock space to feast on. 

Whelks and Sally Lightfoot Crabs are essential lagoon species that keep rock & coral rubble areas and mangrove roots from being overrun by algae and other marine vegetation.

Apparently this crab shouted “You shall go no further! This is my territory. My food”, as it jumped in to block the forward progress of the mollusks.

The crab wedged it’s carapace against the crevice roof and braced its legs for a standoff.

When the whelk could not pass, it devised a plan. Utilizing its buddy’s back the marine snail found an angle from which it could start levering the crab out of the way. However, before the whelks could make any headway, a small unidentified fast-moving crustacean rushed in and startled the crab. (@ 47 seconds). Problem solved and the whelks marched onward!

The entire shoving match lasted three minutes and 20 seconds in real time. The video speed has been increased to show the encounter in one minute.

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