Feature - Locomotion

Snakelock Anemone (Anemonia viridis)

Whilst observing something entirely different, it was noticed that this Snakelock Anemone had possibly moved. It then took several minutes of continuous observation to confirm that it had and indeed was actually still on the move. Once this was realised, a still camera was set up and images taken at certain moments to track its movement and capture a sequence that also illustrates a little of its' method of movement as it passes a Plumose Anemone Metridium senile on the apex of the rock.
The still photographs here shown as an animated sequence, cover a period of around 10 minutes.
In the subsequent 10 minutes it moves around the top of the rock and then falls off the end!
This, along with possible explainations as to why it moved, such as to obtain more light for the algae that it has living within its surface layer of tissue, is shown and explained on the SeaShoreAntics CD.

Locomotion

Movement is indeed something that always occurs when a distance is covered in a period of time. The distance divided by the time gives the speed and speed is one of the wide ranging factors that govern what can easily be observed or not.
Sea Shore Antics seeks out events that occur at a range of speeds and presents them in a format that is easily observed using either real-time or timelapse imaging.
When the speed has been accounted for in the observation, to follow up this with the thinking as to why the effort and expenditure of energy to bother moving in the first place, is worthy of a consideration.

Sea Scorpion (Taurulus bubalis)

This is a real-time animated sequence of the Sea Scorpion accelerating away to strike, in this case, at an unsuspecting prawn. The remarkable thing noticed from this clip was that no preparitory stance or movement before the forward thrust is delivered, is apparent..... it just goes!
The fast speed of this action is to give the target less chance to react and therefore to escape, so is, along with accuracy of direction, a benefit for this ambush preditor.
So rapid acceleration is useful for this activity of striking out at prey, but similar acceleration abilities are used by many, to aid escape from preditors... well worth the investment of energy to create the movement.

Sea Slater (Ligia oceanica)

At and above the high tide mark, hidden within the cracks of rocks, is where the Sea Slater will usually be found during the daytime. It is more active at night, when it will emerge from the crevices and cracks, to forage.... along with all its fellow inhabitants in the area.

To find one out and about during daylight is infrequent. On this occasion several were dislodged by climbers and the journey of one, back to a safe, darkened, haven, was filmed as it occurred. The speed varied from being stationary at times, to a full on pace, sustained for several seconds.
The ability to locomote, both covers the need to forage at night and the need (as in this case), if required, to move to find shelter and protection from such things as preditors, such as Seagulls and also conditions, such as direct sunlight.