Juvenile horseshoe crab behaviour – marginal spine marks

This post documents the behaviour of juvenile horseshoe crabs (Tachypleus tridentatus) based on observations made at an inter-tidal mudflat at Ha Pak Nai, Deep Bay, New Territories, Hong Kong.

All observable juvenile horseshoe crab activity on the mudflat appears to be synchronized with the tides. When the tide comes in, the juveniles bury themselves in the substrate. When the tide recedes, they emerge to forage.

In terms of juvenile horseshoe crab locomotion, two principal types of locomotion are observed – foraging in the substrate and walking on the substrate. This post covers both foraging and walking activity, which result in marginal spine impressions being left in the substrate.