NEW YORK (July 20, 2023) – A small, shy porpoise species has been detected year-round in the New York-New Jersey Harbor Estuary, the largest and busiest port on the U.S. East Coast, according to a research team with the Wildlife Conservation Society (WCS) publishing in the Journal Frontiers in Marine Science.

This research confirms for the first time that harbor porpoises, which are vulnerable to ocean noise and human disturbance, are surprisingly living in the busy, heavily trafficked NY waters throughout the year.

Now that we know these harbor porpoises, highly sensitive to noise, are in the NY harbor year-round, we must continue to advocate for policies at the state and federal level and insist all marine industries take informed actions to reduce ocean noise in the very noisy and increasingly busy NY harbor to protect these marine mammals and all wildlife sharing these waters.

The team used acoustic recorders to detect harbor porpoises (Phocoena phocoena), one of the world’s smallest porpoise species that averages just five feet and 130 pounds. They found the species at low levels year-round, with seasonal peaks from February to June. Sea surface temperature and chlorophyll-a concentration were significant predictors of harbor porpoise presence.

Prior to this study, little was known about harbor porpoise presence in the NY-NJ Harbor Estuary. The most recent verified sightings were on two separate occasions in 2019 (although these were further offshore than the NY/NJ Harbor Estuary) as part of the NYSDEC funded New York Bight Whale Monitoring Aerial Surveys that ran from 2017-2020. The results of the study are timely for informing mitigation and management actions related to a range of current and forthcoming anthropogenic impacts such as increasing vessel traffic and the development of offshore wind cable landing corridors.

The authors say the presence of this acoustically sensitive species in the NY-NJ Harbor Estuary, despite the high level of human activity already taking place, suggests that some individuals may be habituating to a high level of disturbance, or that the foraging opportunities in this area may outweigh the potential impacts. However, they caution there is little information related to potential impacts to this species from disturbances in such a heavily human dominated area.

As one of the busiest waterways along the U.S. East Coast, cetacean species inhabiting waters of the New York Bight and the NY-NJ Harbor Estuary are facing numerous threats including increasing shipping traffic, increased ocean noise levels, expanding offshore wind development, and climate change. Across the broader Northwest Atlantic, and in other areas across their range, harbor porpoises are known to be particularly vulnerable to fisheries bycatch, contaminants, ship traffic, habitat modifications, and offshore wind energy development.

Said the study’s lead author, Dr. Melinda Rekdahl of WCS’s Ocean Giants Program: “This study provides important baseline information about harbor porpoise distribution and interaction with environmental variables in the human-dominated NY-NJ Harbour Estuary. Harbor porpoises are known to be vulnerable to human disturbances and therefore continued and expanded monitoring of their presence and habitat use will be critical for effective conservation efforts moving forward in light of the increasing pressures this region is facing from offshore wind energy development and increasing shipping. This not only applies to our study area, but also the greater New York Bight and Mid-Atlantic region, as more information about this cryptic species is needed in light of the expected shifts in distribution with a changing climate.”

Said co-author and WCS Ocean Giants Director, Dr. Howard C. Rosenbaum: “There is increasingly great interest about whales and dolphins that people may see (from shore, from whale-watch excursions) in the NY-NJ Harbor Estuary. These new acoustic results demonstrate that harbor porpoises are here and for considerable amounts of time throughout the year, even though people don’t typically see them—and that the technology is capable of determining their presence in light of current and forthcoming anthropogenic impacts.”