Kevin D. Friedland

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Menhaden occupy an important position in estuarine food webs, thus the rate processes associated with their feeding are critical to the ecosystem management of fishery and ecological resources. Atlantic menhaden feed on a wide range of plankton, the size and food quality of which change ontogenetically. We analyzed the functional morphology of the menhaden(More)
The shift in marine resource management from a compartmentalized approach of dealing with resources on a species basis to an approach based on management of spatially defined ecosystems requires an accurate accounting of energy flow. The flow of energy from primary production through the food web will ultimately limit upper trophic-level fishery yields. In(More)
Both fisheries exploitation and increased nutrient loadings strongly affect fish and shellfish abundance and production in estuaries. These stressors do not act independently; instead, they jointly influence food webs, and each affects the sensitivity of species and ecosystems to the other. Nutrient enrichment and the habitat degradation it sometimes causes(More)
Information on the effects of global climate change on trends in global fisheries biomass yields has been limited in spatial and temporal scale. Results are presented of a global study of the impact of sea surface temperature (SST) changes over the last 25 years on the fisheries yields of 63 large marine ecosystems (LMEs) that annually produce 80% of the(More)
We examined the contents of the alimentary tract of juvenile Atlantic menhaden, an obligate filter-feeding fish, with epifluoresence microscopy. All plankton taxa and detrital material observed in plankton samples from the sampling area could also be found in the esophagus of the fish. The corresponding plankton taxa were absent from the pre-feces sampled(More)
If climate limits the geographical distribution of a species, local variation in microclimate may affect the species' local distribution at the edge of its range. We hypothesized that warm urban microclimates may explain the distribution of the Virginia opossum (Didelphis virginiana) in central Massachusetts. We recorded winter temperatures with(More)
The ability to understand and ultimately predict ecosystem response to multiple pressures is paramount to successfully implement ecosystem-based management. Thresholds shifts and nonlinear patterns in ecosystem responses can be used to determine reference points that identify levels of a pressure that may drastically alter ecosystem status, which can inform(More)
Scale archives of Atlantic salmon Salmo salar from Maine, U.S.A., were examined to determine whether ocean conditions affected the long-term trends in S. salar populations in the southern tier of the species' range in North America. To date, scale analyses of southern tier populations have been limited to hatchery fish; previous studies suggest that(More)
Photosynthesis fuels marine food webs, yet differences in fish catch across globally distributed marine ecosystems far exceed differences in net primary production (NPP). We consider the hypothesis that ecosystem-level variations in pelagic and benthic energy flows from phytoplankton to fish, trophic transfer efficiencies, and fishing effort can(More)
There has been a systematic change in the weight at age of Atlantic salmon (Salmo salar L.) in the Northwest Atlantic that is related to climate variability. This relationship emerged from analyses of broad-scale measures of ocean surface thermal habitat, which show that expansion of the area bounding 4–8°C is associated with greater growth. To further(More)