The state Department of Environmental Services and Fish and Game Department has stopped clam, mussel and oyster harvesting after finding unacceptably high levels of paralytic shellfish poisoning -- "red tide" -- in blue mussels at the Isles of Shoals and Hampton/Seabrook Harbor.
DES shellfish program manager Chris Nash told the Union Leader news organisation that this year's red tide alert ahs come earlier than usual.
"The toxin levels at the Isles of Shoals are not unusual for this time of year, but the toxin has shown up a bit earlier than usual at Hampton/Seabrook Harbor," Mr Nash said.
The action will affect recreational shellfish harvesters and several aquaculture operations in the Granite State.
Red Tide Halts Shellfish Harvest
US - The New Hampshire authorities have declared its Atlantic coastal waters and Hampton/Seabrook Harbor off-limits to shellfishing to protect the public from eating contaminated shellfish.