Assessing the effects of industrial activity on cetaceans in Trinity Bay, Newfoundland

The effects of industrial activity on cetaceans, including humpback whales (Megaptera novaeangliae), minke whales (Balaenoptera acutorostrata), and harbour porpoise (Phocoena phocoena), in Bull Arm, Trinity Bay, Newfoundland during 1992 (Todd et al., 1996), 1994, and 1995 were assessed. Within-year measures of population abundance and distribution, and individual respiration could not detect effects with certainty. These measures were often too variable, too few, or confounded by effects of season and prey distribution. -- Tracking individual animals within years provided some evidence of the short-term effects from industrial activity. In 1994, when dredging was the predominant activity, humpback whales were less likely to be resighted near the industrial activity and exhibited movement away from the site; no such changes were observed during blasting in 1992 (Todd et al., 1996) or during vessel activity in 1995. Humpback resightings and residency were comparatively higher in 1995 than in other years. Furthermore, minke whale resightings occurred in an area of heavy vessel activity in 1995. Reactions by individual cetaceans appeared to depend on the type of industrial activity. -- Resightings of individually identified animals between years suggested long-term effects of industrial activity on cetaceans. Humpback whales photo-identified in Trinity Bay in 1992 were observed less frequently in Newfoundland in 1993 than were whales identified in other inshore bays. In addition, a lower proportion of humpback whales identified in Trinity Bay in 1992 were resighted in Newfoundland in 1993 compared with animals identified in an undisturbed area Individual minke whales were resighted in the industrial area in a subsequent year. Individually identified whales, monitored for several years, were a more sensitive indicator of long-term impacts of anthropogenic activity than abundance, distribution, and respiration measures

Vulnerability to climate change of United States marine mammal stocks in the western North Atlantic, Gulf of Mexico, and Caribbean.

Climate change and climate variability are affecting marine mammal species and these impacts are projected to continue in the coming decades. Vulnerability assessments provide a framework for evaluating climate impacts over a broad range of species using currently available information. We conducted a trait-based climate vulnerability assessment using expert elicitation for 108 marine mammal stocks and stock groups in the western North Atlantic, Gulf of Mexico, and Caribbean Sea. Our approach combined the exposure (projected change in environmental conditions) and sensitivity (ability to tolerate and adapt to changing conditions) of marine mammal stocks to estimate vulnerability to climate change, and categorize stocks with a vulnerability index. The climate vulnerability score was very high for 44% (n = 47) of these stocks, high for 29% (n = 31), moderate for 20% (n = 22), and low for 7% (n = 8). The majority of stocks (n = 78; 72%) scored very high exposure, whereas 24% (n = 26) scored high, and 4% (n = 4) scored moderate. The sensitivity score was very high for 33% (n = 36) of these stocks, high for 18% (n = 19), moderate for 34% (n = 37), and low for 15% (n = 16). Vulnerability results were summarized for stocks in five taxonomic groups: pinnipeds (n = 4; 25% high, 75% moderate), mysticetes (n = 7; 29% very high, 57% high, 14% moderate), ziphiids (n = 8; 13% very high, 50% high, 38% moderate), delphinids (n = 84; 52% very high, 23% high, 15% moderate, 10% low), and other odontocetes (n = 5; 60% high, 40% moderate). Factors including temperature, ocean pH, and dissolved oxygen were the primary drivers of high climate exposure, with effects mediated through prey and habitat parameters. We quantified sources of uncertainty by bootstrapping vulnerability scores, conducting leave-one-out analyses of individual attributes and individual scorers, and through scoring data quality for each attribute. These results provide information for researchers, managers, and the public on marine mammal responses to climate change to enhance the development of more effective marine mammal management, restoration, and conservation activities that address current and future environmental variation and biological responses due to climate change

Values used in the NOAA climate change web portal to generate climate exposure maps for 108 marine mammal stocks in the western North Atlantic, Gulf of Mexico, and Caribbean Sea.

Values used in the NOAA climate change web portal to generate climate exposure maps for 108 marine mammal stocks in the western North Atlantic, Gulf of Mexico, and Caribbean Sea.</p

Mean sensitivity attribute data quality scores.

Mean data quality scores of climate sensitivity attributes for 108 marine mammal stocks in the western North Atlantic, Gulf of Mexico, and Caribbean Sea. The vertical bar represents the median; the box is bounded by the first and third quartiles; whiskers represent 1.5 times the inter-quartile range; points represent all outlying values.</p

Exposure factor mean scores for all scored stocks.

Exposure factor mean scores for 108 U.S. marine mammal stocks in the western North Atlantic, Gulf of Mexico, and Caribbean Sea. The vertical bar represents the median; the box is bounded by the first and third quartiles; whiskers represent 1.5 times the inter-quartile range; points represent all outlying values.</p

Stocks scored.

List of all marine mammal stocks and stock groupings in the assessment. (XLSX)</p

Sensitivity attributes and scoring criteria used to assess climate vulnerabilities of 108 marine mammal stocks in the western North Atlantic, Gulf of Mexico, and Caribbean Sea.

Sensitivity attributes and scoring criteria used to assess climate vulnerabilities of 108 marine mammal stocks in the western North Atlantic, Gulf of Mexico, and Caribbean Sea.</p

Response variable ordination used in climate vulnerability assessment of 108 stocks of marine mammals from the western North Atlantic, Gulf of Mexico, and Caribbean Sea.

Response variable ordination used in climate vulnerability assessment of 108 stocks of marine mammals from the western North Atlantic, Gulf of Mexico, and Caribbean Sea.</p