Newspapers describe long-term trends in whale occurrence in the nearshore New York Bight

Abstract

To understand trends in species occurrence, it is important to incorporate historical data. The digitization of printed newspapers dating back to colonial times allows for a cost-effective way of acquiring long-term ecological information. We used digital newspaper archives to gather data and characterize trends in whale sightings and strandings in the nearshore (0–25 km) New York Bight (NYB), including the New York-New Jersey harbor estuary and the Delaware estuary. Most records were found from 1831 to 2020. Sighting records per year (RPY) exhibited a bimodal pattern, with a drop in RPY between 1931 and 1970. Stranding RPY showed an increasing trend over time, with separate spikes from 1941-1950 and 2011–2020. The species most often mentioned in newspaper records were right (Eubalaena glacialis), fin (Balaenoptera physalus), humpback (Megaptera novaeangliae), and sperm whales (Physeter macrocephalus). The predominant species in early records were right, fin, and sperm whales, while after 1980 the most commonly reported species were humpback and fin whales. There were species-specific differences in seasonal peaks, but sightings and strandings overall were most often reported in July. Newspapers provided valuable information on the historic occurrence of whales, filling in gaps from time frames prior to formal data collection. These results suggest that the whale species composition of the nearshore NYB has changed over the last two centuries, with a decline in right whales and an increase in humpback whales. The regular occurrence of humpback whales in the region appears to have begun more recently, which conflicts with theories that suggest they may be reoccupying former habitat. The increasing trend found for humpback whales and the evidence that endangered whale species such as right, fin, and sperm whales occur in the nearshore region is important for management and should be considered in future impact assessments.