June 24, 2016 — DURHAM, N.H. — It appears that horseshoe crab spawning is based more on water temperature than lunar cycles, according to new research from the University of New Hampshire.
Researchers found that Atlantic horseshoe crabs in New Hampshire’s Great Bay Estuary time their annual spawning based on water temperature.
It was thought that the lunar cycle triggered spawning.
The study provides a first-of-its-kind look at the environmental factors that influence horseshoe crab spawning activity in the state and could pave the way for changes in how monitoring surveys are conducted on the East Coast.
“We wanted to establish a baseline for horseshoe crab populations in New Hampshire because it had never been done before,” said Helen Cheng, who led the research. “Knowing how a species behaves is important in managing their populations, so we needed to know more about horseshoe crab spawning behaviors for effective management.”
A decline in the horseshoe crab population could affect several fields.
In medicine, horseshoe crabs play an important role in eye research and surgical sutures and a component of their bright-blue blood is used in the pharmaceutical industry.
American eel and conch fisheries use them for bait, and several other species in the ecological food chain depend on them for survival.