Gloucester Pinpoints Source of Pervasive 'Rotten Egg' Odor

An unpleasant odor has engulfed Gloucester, Massachusetts. City authorities have identified the culprit behind this smell reminiscent of sulfurous rotten eggs.

The explanation, unveiled on a Wednesday, points to Heterosiphonia japonica, an invasive species of seaweed from Japan, as the source of the odor in East Gloucester.

As this seaweed reaches the shore and begins to decompose, it emits a smell akin to rotten eggs—a natural phenomenon, according to city officials.

Experiencing a sharp stench in East Gloucester? City officials are fully aware of the potent aroma emanating from the area.

This invasive seaweed, which arrived on the North Shore courtesy of storm activity, led to massive surf and significant waves impacting the eastern seaboard, temporarily closing several beaches in Massachusetts to swimmers due to hazardous rip currents.

The recent hurricane forcefully swept large volumes of the seaweed inland, depositing it within the Good Harbor estuary. With a lack of subsequent tides strong enough to carry it back out to sea, the seaweed remains, decomposing and releasing its offensive odor.

First discovered on the eastern coastline in 2009, Heterosiphonia japonica was initially collected near Rhode Island. The species tends to spread rapidly and has been associated with the decline of fish populations.

Residents commenting on social media likened the offensive scent to that of natural gas, with a few likening it to the smell of sewage.

The alarming and pervasive stench has been noted by many, with one observer declaring it far from the typical low-tide seaweed smell.

Another remarked on the intensity of the smell, joking that it seemed a large animal had expired in the marsh.

Officials have reassured residents that the smell will diminish over time as the seaweed continues to break down.