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The uncertainty of future ocean conditions caused by climate change challenges the conventional fisheries management model that assumes resource extraction occurs in a steady-state environment. As managers respond to climate impacts and focus on long-term preparedness, an overarching goal is to minimize the vulnerability of fishing businesses and communities. However, during the adaptation process, challenges can arise when perceptions of climate change vulnerability differ among scientists, managers, and harvesters. A harvester’s perception of their risk to climate change influences their willingness to plan for and respond to change, yet these views are often overlooked in adaptation planning. To better understand this dynamic, we conducted a regional survey to evaluate the perceptions harvesters hold regarding the impacts of climate change on commercially fished species in the Northeastern United States and the resulting risks from those changes. The waters in this region of the Northwest Atlantic shelf are warming faster than the global average resulting in shifting distributions of species, altered seasonal migrations, and changes in productivity. Respondents’ perceptions aligned with an analysis conducted by scientists on the directionality of climate impacts for 12 out of 27 (44%) of the most commercially important species in the region. Additionally, an understanding of the variability in perceptions of climate change vulnerability emerged: 72% of respondents believe climate change is occurring, 53% believe climate change will harm them personally, and 28% have already seen a negative impact on their ability to catch fish. Respondents who believe that climate change is occurring had higher perceptions of vulnerability on average than those who do not believe it is occurring. Despite a sense of vulnerability to climate change, respondents did not rank it among the top three concerns (fisheries regulations, market access, and access to working waterfronts) for their fishing businesses. Investigating harvester’s perceptions is an opportunity to share their experiences and understand the diversity of perspectives regarding the impacts of climate change. Increasing the inclusion of social science indicators and diverse perspectives will increase climate resilience of fisheries management.

The mid-Holocene decline of eastern hemlock is widely viewed as the sole prehistorical example of an insect- or pathogen-mediated collapse of a North American tree species and has been extensively studied for insights into pest-host dynamics and the consequences to terrestrial and aquatic ecosystems of dominant-species removal. We report paleoecological evidence implicating climate as a major driver of this episode. Data drawn from sites across a gradient in hemlock abundance from dominant to absent demonstrate: a synchronous, dramatic decline in a contrasting taxon (oak); changes in lake sediments and aquatic taxa indicating low water levels; and one or more intervals of intense drought at regional to continental scales. These results, which accord well with emerging climate reconstructions, challenge the interpretation of a biotically driven hemlock: decline and highlight the potential for climate change to generate major, abrupt dynamics in forest ecosystems. [ABSTRACT FROM AUTHOR]

Hurricanes are a major factor controlling ecosystem structure, function, and dynamics in many coastal forests, but their ecological role can be understood only by assessing impacts in space and time over a period of centuries. We present a new method for reconstructing hurricane disturbance regimes using a combination of historical research and computer modeling. Historical evidence of wind damage for each hurricane in the selected region is quantified using the Fujita scale to produce regional maps of actual damage. A simple meteorological model (HURRECON), parameterized and tested for selected recent hurricanes, provides regional estimates of wind speed, direction, and damage for each storm. Individual reconstructions are compiled to analyze spatial and temporal patterns of hurricane impacts. Long-term effects of topography on a landscape scale are then simulated with a simple topographic exposure model (EXPOS). We applied this method to the region of New England, USA, examining hurricanes since European settlement in 1620. Results showed strong regional gradients in hurricane frequency and intensity from southeast to northwest: mean return intervals for F0 damage on the Fujita scale (loss of leaves and branches) ranged from 5 to 85 yr, mean return intervals for F1 damage (scattered blowdowns, small gaps) ranged from 10 to .200 yr, and mean return intervals for F2 damage (extensive blowdowns, large gaps) ranged from 85 to .380 yr. On a landscape scale, mean return intervals for F2 damage in the town of Petersham, Massachusetts, ranged from 125 yr across most sites to .380 yr on scattered lee slopes. Actual forest damage was strongly dependent on land use and natural disturbance history. Annual and decadal timing of hurricanes varied widely. There was no clear centuryscale trend in the number of major hurricanes. The historical-modeling approach is applicable to any region with good historical records and will enable ecologists and land managers to incorporate insights on hurricane disturbance regimes into the interpretation and conservation of forests at landscape to regional scales., Organismic and Evolutionary Biology

Hurricanes represent an important natural disturbance process to tropical and temperate forests in many coastal areas of the world. The complex patterns of damage created in forests by hurricane winds result from the interaction of meteorological, physiographic, and biotic factors on a range of spatial scales. To improve our understanding of these factors and of the role of catastrophic hurricane wind as a disturbance process, we take an integrative approach. A simple meteorological model (HURRECON) utilizes meteorological data to reconstruct wind conditions at specific sites and regional gradients in wind speed and direction during a hurricane. A simple topographic exposure model (EXPOS) utilizes wind direction predicted by HURRECON and a digital elevation map to estimate landscape—level exposure to the strongest winds. Actual damage to forest stands is assessed through analysis of remotely sensed, historical, and field data. These techniques were used to evaluate the characteristics and impacts of two important hurricanes: Hurricane Hugo (1989) in Puerto Rico and the 1938 New England Hurricane, storms of comparable magnitude in regions that differ greatly in climate, vegetation, physiography, and disturbance regimes. In both cases patterns of damage on a regional scale were found to agree with the predicted distribution of peak wind gust velocities. On a landscape there was also good agreement between patterns of forest damage and predicted exposure in the Luquillo Experimental Forest in Puerto Rico and the town of Petersham, Massachusetts. At the Harvard and Pisgah Forests in central New England the average orientation of wind—thrown trees was very close to the predicted peak wind direction, while at Luquillo there was also good agreement, with some apparent modification of wind direction by the mountainous terrain. At Harvard Forest there was evidence that trees more susceptible to windthrow were felled earlier in the storm. This approach may be used to study the effects of topography on wind direction and the relation of forest damage to wind speed and duration; to establish broad—scale gradients of hurricane frequency, intensity, and wind direction for particular regions; and to determine landscape—level exposure to long—term hurricane disturbance at particular sites., Organismic and Evolutionary Biology