Figure 31

Loggerhead sea turtles that inhabit the U.S. NES LME in the spring and summer predominantly derive from nesting beaches in Florida. Climate conditions, as indicated by the North Atlantic Oscillation (NAO), 1-year prior to each nesting season were associated with the interannual nest count variability in Florida nesting beaches (Figure 31). This suggests that loggerhead prey availability was associated with the NAO such that positive phases were associated with increased prey availability, enhanced body conditioning for mature females (fat reserves), and thus a higher number of nests in Florida beaches.

Figure 32

Fishing activity has caused a decline in the Northwest Atlantic cusk population, which has led a review of this species for listing under the U.S. Endangered Species Act. Therefore, it is critical that the potential impacts of climate change are assessed for this species. By coupling a species niche model with climate model projections, it is suggested that cusk habitat in this region will shrink and fragment resulting from a spatial mismatch between critical seafloor habitat and preferred temperature (Figure 32).

Figure 33

Figure 34

Figure 35

Figure 36

The term river herring collectively refers to alewife (Alosa pseudoharengus) and blueback herring (A. aestivalis), two anadromous fishes distributed along the east coast of North America. Historically, river herring spawning migrations supported important fisheries, and their spawning runs continue to be of cultural significance to many coastal communities. Substantial declines in spawning run size prompted a petition to consider river herring for listing under the Endangered Species Act (ESA). The ESA status review process requires an evaluation of a species’ response to multiple stressors, including climate change. Climate projections of ocean warming along the US Atlantic coast indicate that climate change will likely result in reductions in total suitable habitat across the study region, which will alter the marine distribution of river herring (Figures 33, 34, 35, 36; Lynch et al., 2015). Spring conditions (Figures 33 and 35) may become more favorable, except in the Mid-Atlantic, whereas fall conditions (Figures 34 and 36) may become less favorable throughout the Northeast U.S. Shelf.

Figure 36.1

Figure 36.2

Because of their diadromous life history, variability in rates of survival in fresh water can affect overall recruitment. A study published in 2015 (Tommasi et al. 2015) assessed how river temperature and flow influence young of the year (YOY) river herring recruitment in the Northeast U.S. Observations of adult and juvenile fish in five rivers were used to construct spawner-YOY recruits models; these rivers were chosen because of the length of the time series (>15 years) and the paired observations of spawners and juveniles. An environmentally explicit stock-recruitment model explained a substantial fraction (41% to 80%) of the variance in YOY abundance, depending on river system (Figures 36.1 and 36.2). This approach allowed for a preliminary discussion of potential mechanisms, which need to be further substantiated by focused field and laboratory studies. Early summer river flow and river temperature had the greatest influence, indicating the importance of conditions in nursery habitats. In certain systems, spring or fall conditions were also important determinants of survival, suggesting additional effects of the environment on spawning of adults and juvenile egress from freshwater nursery habitats.

The North Atlantic Right Whale (Eubalaena glacialis) is endangered throughout its range, with approximately 450 extant individuals. Two areas of critical habitat have been designated in the U.S. waters of the Northeast U.S. Shelf: Cape Cod Bay and Great South Channel (Figure 37). North Atlantic Right Whale use of the Gulf of Maine has been linked to the abundance and distribution of a major prey species: Calanus finmarchicus (Pershing et al. 2009; Pendleton et al. 2012; Movie 20). Recent work also suggests that Right Whale calving is related to climate forced changes in Calanus finmarchicus abundance (Meyer-Gutbrod and Greene, 2014). Scientists at the NEFSC have started a study to project the effects of climate change on Calanus finmarchicus to further understand the effect of climate change on the North Atlantic Right Whale.