Juvenile horseshoe crab behaviour - burrowing

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.

The following photographs show two instances of juvenile T. tridentatus burrowing on the exposed mudflat:

Burrowing 1

Juvenile T. tridentatus sprints across the mudflat, then burrows into the sandy substrate.

Burrowing 2

Juvenile T. tridentatus burrowing into sandy substrate

Comment

Understanding the way that tidal cycles dictate the foraging and burrowing activities of juvenile horseshoe crabs may help in the interpretation of the palaeo-environment of other localities with horseshoe crab fossils, such as Mazon Creek.