Diary: Tuesday 26th March 2002
Conditions at New Brighton
SUNSET: –6.31 pm
TIDE: – Low 8:21 pm. (0.3 m)
MOON: – Set 2:36 am. Rise 5:32 pm. Three days before full Moon.
(First SSL & one CP are still submerged in the sandpit.)
‘At 8 pm headed to beach with a torch to observe the nocturnal activities down there. Brought a caterpillar home to photo; same sort as dig in near the sea. It moves in sand at the base of dunes on the flatter area about three body lengths a minute. Found one SSL about 25 mm long (1 inch) trekking along on the sloping sand at the base of the dunes. Some of it’s journey was quite steep and several times had rolled down a little way, then carried on. The tracks went for 5 metres with about the same speed as the caterpillar. It uses its mouth-parts as an extra ‘pair of legs.’ I think CP moves a little faster as they have the bonus of a bit more ‘push’ by using their tail end. It is this rear push which marks the sand with their distinctive signature. Was not fortunate enough to see either a SSL or CP venturing out to sea. Came home and did sums.
5 metres divided by 25 mm (or 1 minute) = 200 minutes! Three hours and twenty minutes on loose dry sloping sand.
That’s a seriously rough calculation and I bet the going would be far quicker on the firmer sand, but what a mammoth and laborious pilgrimage for such a slow grub to undertake. Guess they need an early start to even contemplate accomplishing this feat.’