Indigenous culture and adaptation to climate change: sockeye salmon and the St’át’imc people

This paper provides a culturally-informed understanding of the impacts of climate change on a highly important subsistence activity that has been practiced by First Nations of central British Columbia for thousands of years. The paper begins with a review of the science regarding sockeye salmon and climate change. It discusses harvest patterns, and how the timing of runs has changed. A survey was conducted by the first author regarding St’át’imc traditional fishing at a historic site on the Fraser River, in 2005. The results show that the impacts of climate change are apparent to those conducting traditional fishing practices, in terms of changed timing and abundance of salmon runs. These perceptions fit closely with the information available from scientists and management agencies. These changes are highly problematic for the St’át’imc, in that the preservation method (drying) is tied to seasonal weather patterns. The whole cultural setting, and the relevance of salmon for subsistence would be highly altered by climate change that leads to changes in the timing and abundance of sockeye salmon. The paper discusses mitigation and adaptation alternatives, but also indicates the scope of these seem limited, given the resource systems and the context of these activities.     

Characterization of fatal occupational versus nonoccupational motor vehicle collisions in Kentucky (1998-2000)

Motor vehicle collisions (MVCs) are the leading cause of occupational fatalities in Kentucky as well as in the nation. The characteristics of and contributing factors for occupational versus nonoccupational MVC fatalities in the Commonwealth of Kentucky were examined from 1998 to 2000. Semi trucks were most frequently involved in fatal occupational MVCs, and passenger cars were most frequently involved in nonoccupational MVCs. More than half of the decedent drivers resided outside of Kentucky. The percentage of occupational fatalities occurring on a four-lane highway was double the percentage observed for nonoccupational MVC fatalities. In addition, an increased proportion of occupational MVC deaths occurred on limited access highways compared to nonoccupational fatalities. When human factors contributing to these fatal incidents were examined, the two primary human factors involved in occupational motor vehicle fatalities were driver distraction/inattention and falling asleep, whereas unsafe speed and alcohol were the primary human factors contributing to a nonoccupational fatality. These results suggest that semi drivers traveling on four-lane highways are more at risk for a fatal occupational injury in Kentucky. Therefore, additional epidemiological studies are needed to further examine human factors, the nature of the Kentucky highway system, and trucking controls (e.g., weigh station hours of operation) within the Kentucky transportation industry.     

Seasonal variation in ejaculate traits of male red-winged blackbirds (Agelaius phoeniceus)

Many reproductive traits, including ejaculate characteristics, usually show remarkable seasonal variation, but the potential for such dynamics in sperm morphology has been overlooked. Several studies have revealed high within-male repeatability in sperm morphology, but samples have typically been collected within a few hours or days, and the consistency of sperm morphology over longer periods remains unexplored. Here, we tested whether ejaculate traits, including sperm morphology, sperm number, and sperm velocity, exhibit seasonal phenotypic plasticity in a long-lived seasonal breeder, the red-winged blackbird (Agelaius phoeniceus). We found absolute and/or relative flagellum length and sperm velocity to increase across the season, whereas sperm numbers within ejaculates declined. Sperm morphological traits were further positively associated with harem size or the total number of offspring that fledged in each male’s territory, suggesting that sperm morphology is likely to be linked to male reproductive quality. The underlying mechanisms of these patterns of seasonal variation remain unresolved, but we discuss our results in the context of dynamics of reproductive hormones, testicular structures and function, and reproductive behavior.     

Movements and depth/temperature distribution of the ectothermic Scombrid, Acanthocybium solandri (wahoo), in the western North Atlantic

Pop-up satellite archival tags were deployed onto four wahoo during 2006 in the western North Atlantic (~26.5°N, 79.3°W), providing movement, depth, and temperature data collected over a total of 198?days. Straight-line distances between tag deployment and pop-off positions ranged from 162.5 to 1,960.0?km. Wahoo spent >90?% of their time in water <200?m, and >90?% of their time in water between 17.5 and 27.5?°C. Three fish made regular trips to depths >200?m. All four fish had significantly different depth distributions between the dark and light periods (Kruskal–Wallace test, p?相似文献   

Ontogenetic changes in alarm-call production and usage in meerkats (<Emphasis Type="Italic">Suricata suricatta</Emphasis>): adaptations or constraints?

In many species, individuals suffer major mortality in their first year because of predation. Behaviours that facilitate successful escape are therefore under strong selection, but anti-predator skills often emerge gradually during an individual’s early development. Using long-term data and acoustic recordings of alarm calls collected during natural predator encounters, we aimed to elucidate two largely unsolved issues in anti-predator ontogeny: (1) whether incorrect predator assignment is adaptively age-appropriate, given that vulnerability often changes during development, or whether age-related differences reflect true mistakes made by immature individuals; and (2) the extent to which the development of adult-like competence in alarm-call production and usage is simply a function of maturational processes or dependent upon experience. We found that young meerkats (Suricata suricatta) were less likely to give alarm calls than adults, but alarmed more in response to non-threatening species compared to adults. However, stimuli that pose a greater threat to young than adults did not elicit more calling from young; this argues against age-related changes in vulnerability as the sole explanation for developmental changes in calling. Young in small groups, who were more likely to watch out for predators, alarmed more than less vigilant young in larger groups. Moreover, despite similarities in acoustic structure between alarm call types, calls appeared in the repertoire at different rates, and those that were associated with frequently encountered predators were produced relatively early on. These results indicate that experience is a more plausible explanation for such developmental trajectories than maturation.     

用于CO2捕集的Mg(OH)2粉末溶解速率

氢氧化镁是一种正在研究的用于脱除烟气中低浓度CO2的化学吸收剂。为了掌握工业用氢氧化镁粉末的溶解速率,利用缓冲溶液,在不改变溶液体积的情况下对不同悬浊液浓度、溶液温度、溶液pH值和搅拌速率情况下的氢氧化镁粉末溶解速率进行了研究。提高悬浊液浓度、提高溶液温度、降低溶液pH值和提高搅拌速率均能增大氢氧化镁的溶解速率。悬浊液浓度从0.1 mol/L增加到1 mol/L时,溶解速率增大了2.2倍;温度从23℃增加到52℃时,溶解速率增大了4.3～9.5倍;pH值从9.8降低到6.6时,溶解速率增大了78～225倍;搅拌速率从350 r/min增加到700 r/min时,溶解速率增大了1～2倍。     

Behavioural switching in a central place forager: patterns of diving behaviour in the macaroni penguin (Eudyptes chrysolophus)

Recording the activity of animals as they migrate or forage has proven hugely advantageous to understanding how animals use their environment. Where animals cannot be directly observed, the problem remains of how to identify distinct behaviours that represent an animal’s decision-making process. An excellent example of this problem is that of foraging penguins, which travel to sea to find prey to provision their young. Without direct sampling of the prey field, we cannot calibrate patterns of movement with prey capture, and therefore we cannot determine how different activities link to decision-making. To overcome this, we use a hidden markov model (HMM), which is a machine-learning technique that seeks to identify the underlying states of a system from observable outputs. We apply HMM to determine classes of behaviour from repetitive dives. We take dive data from 103 breeding macaroni penguins at Bird Island, South Georgia, for which we have measures of weight gain over a trip. We identify two classes of behaviour; those of short-shallow and long-deep dives. Using these two behaviours, we calculate the transition probabilities between these states and analyse these data to determine what predicts variation in the transition probabilities. We found that the stage of reproduction during a season, the sex and year of an individual influenced the probability of transition between long-deep and short-shallow sequential dives. We also found differences in the hourly transition rates between the four reproductive stages (incubation, broodguard, crèche and premoult) over a daily cycle. We conclude that this application of HMMs for behavioural switching is potentially useful for other species and other types of recorded behaviour.     

Localising the global food system

Agricultural systems have become increasingly industrialized and mechanized, relying on machinery and chemical inputs, rather than people and natural processes, to increase yields of food. The trend towards an increasingly globalised food system encourages unsustainable transportation of food around the world. Agricultural intensification and the globalisation of the agrofood chain has resulted in adverse environmental, social and economic consequences impeding moves towards sustainability. Organic farming can overcome many of the environmental problems associated with agricultural intensification. However, it does not have the potential to fully address the social and economic problems caused by the globalisation of the food system. Organic farming must be combined with local and regional sourcing of food products, for instance through forms of direct marketing of organic produce. Direct marketing schemes such as farmers' markets, food box delivery schemes and community-supported agriculture are all projects which, if managed with sustainability as the prime objective, have the potential to move towards a more socially, environmentally and economically sustainable agrofood system.