The widespread depletion of commercially exploited marine living resources is often seen as a general failure of management and results in criticism of contemporary management procedures. When populations show dramatic and positive changes in population size, this invariably leads to questions about whether favorable climatic conditions or good management (or both) were responsible. The Barents Sea cod (Gadus morhua) stock has recently increased markedly and the spawning stock biomass is now at an unprecedented high. We identify the crucial social and environmental factors that made this unique growth possible. The relationship between vital rates of Barents Sea cod stock productivity (recruitment, growth, and mortality) and environment is investigated, followed by simulations of population size under different management scenarios. We show that the recent sustained reduction in fishing mortality, facilitated by the implementation of a "harvest control rule," was essential to the increase in population size. Simulations show that a drastic reduction in fishing mortality has resulted in a doubling of the total population biomass compared with that expected under the former management regime. However, management alone was not solely responsible. We document that prevailing climate, operating through several mechanistic links, positively reinforced management actions. Heightened temperature resulted in an increase in the extent of the suitable feeding area for Barents Sea cod, likely offering a release from density-dependent effects (for example, food competition and cannibalism) through prolonged overlap with prey and improved adult stock productivity. Management and climate may thus interact to give a positive outlook for exploited high-latitude marine resources.gadoids | population dynamics | quota | ocean warming | polar displacement

Objective-As we previously reported, ADAMTS-7 and ADAMTS-12, two members of ADAMTS (adisintegrin and metalloprotease with thrombospondin motifs) family, degrade COMP in vitro and are significantly induced in the cartilage and synovium of arthritic patients. The purpose of this study was to determine 1) whether cleavage activity of ADAMTS-7 and-12 of COMP are associated with COMP degradation in osteoarthritis; 2) whether a2M is a novel substrate for ADAMTS-7 and-12; and 3) whether a2M inhibits ADAMTS-7 or-12 cleavage of COMP. Methods-An in vitro digestion assay was used to examine the degradation of COMP by ADAMTS-7 and ADAMTS-12 in the cartilage of OA patients; in cartilage explants incubated with TNF-α or IL-1β with or without blocking antibodies; and in human chondrocytes treated with specific siRNA to knock down ADAMTS-7 or/and-12. Digestion of alpha-2-macroglobulin (a2M) by ADAMTS-7 and-12 in vitro and the inhibition of ADAMTS-7 or-12-mediated digestion of COMP by α2M were also analyzed. Results-The molecular mass of the COMP fragments produced by either ADAMTS-7 or ADAMTS-12 were similar to those observed in OA patients. Specific blocking antibodies against ADAMTS-7 and ADAMTS-12 dramatically inhibited TNF-α-or IL-1β-induced COMP degradation in the cultured cartilage explants. The suppression of ADAMTS-7 or ADAMTS-12 expression by siRNA silencing in the human chondrocytes also prevented TNF-α-or IL-1β-induced COMP degradation. Both ADAMTS-7 and ADAMTS-12 were able to cleave α 2 M, giving rise to 180 and 105 kDa cleavage products, respectively. Furthermore, α 2 M inhibited both ADAMTS-7-and ADAMTS-12-mediated COMP degradation in a concentration (or dose)-dependent manner. Conclusion-Our observations demonstrate the importance of COMP degradation by ADAMTS-7 and ADAMTS-12 in vivo. Furthermore, α 2 M is a novel substrate for ADAMTS-7 and ADAMTS-12. More significantly, α 2 M represents the first endogenous inhibitor of ADAMTS-7 and ADAMTS-12.

Climate-related shifts in marine mammal range and distribution have been observed in some populations; however, the nature and magnitude of future responses are uncertain in novel environments projected under climate change. This poses a challenge for agencies charged with management and conservation of these species. Specialized diets, restricted ranges, or reliance on specific substrates or sites (e.g., for pupping) make many marine mammal populations particularly vulnerable to climate change. High-latitude, predominantly ice-obligate, species have experienced some of the largest changes in habitat and distribution and these are expected to continue. Efforts to predict and project marine mammal distributions to date have emphasized data-driven statistical habitat models. These have proven successful for short time-scale (e.g., seasonal) management activities, but confidence that such relationships will hold for multi-decade projections and novel environments is limited. Recent advances in mechanistic modeling of marine mammals (i.e., models that rely on robust physiological and ecological principles expected to hold under climate change) may address this limitation. The success of such approaches rests on continued advances in marine mammal ecology, behavior, and physiology together with improved regional climate projections. The broad scope of this challenge suggests initial priorities be placed on vulnerable species or populations (those already experiencing declines or projected to undergo ecological shifts resulting from climate Silber et al.Projecting Marine Mammal Distributions changes that are consistent across climate projections) and species or populations for which ample data already exist (with the hope that these may inform climate change sensitivities in less well observed species or populations elsewhere). The sustained monitoring networks, novel observations, and modeling advances required to more confidently project marine mammal distributions in a changing climate will ultimately benefit management decisions across time-scales, further promoting the resilience of marine mammal populations.

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