Transmission of Indigenous Knowledge and Bush Skills Among the Western James Bay Cree Women of Subarctic Canada

The transmission of 93 items of women's indigenous knowledge and bush skills was studied in two subarctic Omushkego (West Main) Cree Indian communities, Moose Factory and Peawanuck, Ontario, Canada. About half of all bush skills were still being transmitted at the hands-on learning stage. Some skills such as setting snares and fishnets, beadwork, smoking geese, and tanning moose and caribou hides were transmitted well. Many skills no longer essential for livelihoods, such as some fur preparation skills and food preservation techniques, were not. Loss of certain skills and incomplete transmission of others (a lower level of mastery than in older generations) were attributable to changes in the educational environment, diminished time available in the bush, problems related to learning bush skills at later ages, and changes in value systems. These factors seemed to impair the traditional mode of education based on participant observation and apprenticeship in the bush, which provided the essential self-disciplining educational environment. Policy measures to counteract these trends may include the institution of a hunters' income security program to provide incentives for family units to go on the land, rather than all-male hunting parties.     

Variation in Swidden practices in four central Brazilian Indian societies

It has been suggested that indigenous tropical forest agriculture, in contrast with other agricultural systems, is characterized by a high degree of polyculture, and, being similar in diversity to the forest itself, has little disturbing effect on the generalized ecosystem that surrounds native gardens. Our comparative study of four Central Brazilian Indian groups shows, however, that while each of these groups practices polyculture to some extent, the crop mix found in their swidden plots is highly patterned, and includes single crop stands at certain stages of garden life. Different crops are planted in the same swidden plot from year to year, in accordance with variation in soil fertility within the swidden cycle. None of the swiddens we observed compares in complexity to the surrounding forest. We suggest that polyculture, rather than being regarded as the distinguishing characteristic of swidden cultivation, should be considered as a varying dimension—along with other variables such as use of wild plants, soil fertility and exhaustion, tillage practices, the introduction of novel crops, and production for the market—within the overall subsistence strategy of a group.     

Creating a community resource for protein science

Helen Berman is the recipient of the Protein Society 2012 Carl Branden Award In addition to being one of the early pioneers in protein crystallography, Carl Brändén made significant contributions to science education with his elegant and beautifully illustrated book Introduction to Protein Structure (Brändén and Tooze, New York: Garland, 1991). It is truly an honor to receive this award in their names. This award and the 40th anniversary of the Protein Data Bank (PDB; Berman et al., Structure 2012;20:391–396) have given me an opportunity to reflect on the various components that have contributed to building a resource for protein science and to try to quantify the impact of having PDB data openly available.     

Limited recovery following a massive seagrass decline in subarctic eastern Canada

Over the last few decades, there has been an increasing recognition for seagrasses' contribution to the functioning of nearshore ecosystems and climate change mitigation. Nevertheless, seagrass ecosystems have been deteriorating globally at an accelerating rate during recent decades. In 2017, research into the condition of eelgrass (Zostera marina) along the eastern coast of James Bay, Canada, was initiated in response to reports of eelgrass decline by the Cree First Nations of Eeyou Istchee. As part of this research, we compiled and analyzed two decades of eelgrass cover data and three decades of eelgrass monitoring data (biomass and density) to detect changes and assess possible environmental drivers. We detected a major decline in eelgrass condition between 1995 and 1999, which encompassed the entire east coast of James Bay. Surveys conducted in 2019 and 2020 indicated limited changes post-decline, for example, low eelgrass cover (<25%), low aboveground biomass, smaller shoots than before 1995, and marginally low densities persisted at most sites. Overall, the synthesized datasets show a 40% loss of eelgrass meadows with >50% cover in eastern James Bay since 1995, representing the largest scale eelgrass decline documented in eastern Canada since the massive die-off event that occurred in the 1930s along the North Atlantic coast. Using biomass data collected since 1982, but geographically limited to the sector of the coast near the regulated La Grande River, generalized additive modeling revealed eelgrass meadows are affected by local sea surface temperature, early ice breakup, and higher summer freshwater discharge. Our results caution against assuming subarctic seagrass ecosystems have avoided recent global declines or will benefit from ongoing climate warming.     

Rapid environmental degradation in a subarctic ecosystem influences resource use of a keystone avian herbivore

1. Environmental degradation can change resource use strategies of animals and thereby affect survival and fitness. Arctic herbivores may be especially susceptible to the effects of such environmental change because their rapid growth rates demand high-quality forage, which may be limited as environmental conditions deteriorate. We studied the consequences of a trophic cascade, driven by Lesser Snow Goose (Chen caerulescens caerulescens) overgrazing on the south-west coast of Hudson Bay, Canada, which has caused tidal marsh (TM) degradation and the reduction in high-quality forage plants, on gosling growth and resource use. 2. We compared resource use and body size of goslings that inhabited tidal and freshwater marsh (FM) to determine how current foraging strategies influence growth and to test the hypothesis that during early growth goslings require and so consume high-quality TM plants, but that during later growth they may switch to foraging in lower-quality FM. 3. To investigate gosling resource use throughout growth, we measured once a week for 28 days the body size of goslings as well as stable isotope ratios (δ(34) S, δ(15) N and δ(13) C) in multiple tissues of goslings that were collected from both TM and nearby FM. We also measured the stable isotope ratios in forage plants sampled along transects and from gosling foreguts. We used an isotope-mixing model to determine the contribution of FM plants to gosling tissues. 4. Contrary to the proposed hypothesis, goslings inhabiting FM or TM primarily consumed FM plants during early growth. Furthermore, goslings that foraged extensively in FM had similar growth rates and grew to a similar size and body mass, as goslings that foraged in the degraded TM. However, goslings that currently inhabit freshwater or TM were significantly smaller than goslings that inhabited TM in the 1980s prior to habitat degradation. 5. Consequences of smaller overall body size include decreased survival and fecundity for arctic-nesting geese. The ability of phenotypically plastic responses to sustain persistence is limited by reaction norms and the extent of environmental change. Current research is assessing whether those limits have been reached in this system.     

Diversity and indicator species as measures of water pollution in a subarctic lake

Benthic invertebrates were collected from a subarctic lake during 1976 to assess the effectiveness of diversity indices and indicator species as measures of heavy metal pollution. Collections were made near an operating metal mine, where sediments were contaminated with high levels of arsenic (up to 2,500 mg/kg dry weight), mercury (500 µg/kg), lead (850 mg/kg), copper (750 mg/kg) and zinc (950 mg/kg). A total of 25 species and a diversity index of 2.4—2.9 were recorded in this heavily impacted area. Chironomids (Procladius denticulatus, Heterotrissocladius changi, Chironomus decorus) were most common in the sediments, followed in importance by molluscs (Pisidium casertanum) and oligochaetes (Lumbriculus variegatus). There were 23 and 25 species in the areas of moderate and negligible contamination, respectively. The diversity indices ranged from 2.4–2.6 and 2.4–2.8 and the main species were generally similar to those found in the heavily impacted area. While diversity indices and indicator species were therefore ineffective in monitoring metal contamination, the strong negative correlation between the concentration of metals and the abundance of benthic organisms provided a much more realistic assessment of the level of contamination.     

High fertility in a Peruvian Amazon Indian village

The relation between fertility and cultural change in a Peruvian Amazon Indian village was studied initially in 1964 and in more detail in 1969. The 1969 study included observations concerning social, economic, environmental, cultural, and health changes. Population growth in the village is nearly 5% per year, and fertility appears to exceed that previously recorded for other groups. The factors that may be contributing to the high fertility are explored. They are thought to include early and prolonged parity, nearly universal marriage and fertility, high reproductive efficiency, short birth intervals, Western health intervention lowering both infant and maternal mortality rates, and a decline in the prevalence of polygyny.Presented at the 99th annual meeting of the American Public Health Association, Minneapolis, Minnesota, October 13, 1971. The project upon which this publication is based is supported by Bureau of Health Services Training Grant #8-TO1OHSOO17-04.     

Scaling net ecosystem CO2 exchange from the community to landscape‐level at a subarctic fen

Landscape‐ and community‐level CO₂ measurements were made at a subarctic sedge fen near Churchill Manitoba during the 1997 growing season. Climatic conditions were warmer and drier than the 30‐y normal. Landscape‐scale micrometeorological measurements indicated that the wetland gained 49 g CO₂ m^?2 during the growing season. Chamber‐scale measurements from the main vegetation community types showed that small hummocks (Carex spp. sites) dominated the CO₂ exchange, yielding an effective scaling factor of 70%. Scaled parameters of two algorithms describing photosynthesis and respiration for each community type show strong similarity to those derived at the landscape level. Scaling photosynthesis, respiration, and net ecosystem CO₂ exchange from the community to landscape‐level over the season is within the maximum probable error of each methodological approach and helps substantiate the 1997 CO₂ budget. We explore the equilibrium response of net ecosystem CO₂ exchange of this fen to climatic change by examining the feedback of water table position on vegetation distribution and nitrogen availability. Based on the effective scaling factors computed for each community type, we hypothesize that a small decrease in mean water table position could nearly triple the net uptake of CO₂ at this wetland.     

Increased variance in temperature and lag effects alter phenological responses to rapid warming in a subarctic plant community

Summer temperature on the Cape Churchill Peninsula (Manitoba, Canada) has increased rapidly over the past 75 years, and flowering phenology of the plant community is advanced in years with warmer temperatures (higher cumulative growing degree days). Despite this, there has been no overall shift in flowering phenology over this period. However, climate change has also resulted in increased interannual variation in temperature; if relationships between phenology and temperature are not linear, an increase in temperature variance may interact with an increase in the mean to alter how community phenology changes over time. In our system, the relationship between phenology and temperature was log‐linear, resulting in a steeper slope at the cold end of the temperature spectrum than at the warm end. Because below‐average temperatures had a greater impact on phenology than above‐average temperatures, the long‐term advance in phenology was reduced. In addition, flowering phenology in a given year was delayed if summer temperatures were high the previous year or 2 years earlier (lag effects), further reducing the expected advance over time. Phenology of early‐flowering plants was negatively affected only by temperatures in the previous year, and that of late‐flowering plants primarily by temperatures 2 years earlier. Subarctic plants develop leaf primordia one or more years prior to flowering (preformation); these results suggest that temperature affects the development of flower primordia during this preformation period. Together, increased variance in temperature and lag effects interacted with a changing mean to reduce the expected phenological advance by 94%, a magnitude large enough to account for our inability to detect a significant advance over time. We conclude that changes in temperature variability and lag effects can alter trends in plant responses to a warming climate and that predictions for changes in plant phenology under future warming scenarios should incorporate such effects.     

Niche use and resource partitioning of Arctic charr,European whitefish and grayling in a subarctic lake

Arctic charr and European whitefish are common species in northern Europe, but have a parapatric distribution pattern and rarely coexist in substantial densities within the same lake. Whitefish is considered to be the strongest competitor, usually causing competitive relegation or exclusion of co-occurring charr. Some exceptions do however occur, and the present study addresses niche utilization and resource partitioning of an Arctic charr population coexisting with whitefish and grayling in a subarctic lake. There was a distinct resource partitioning with respect to habitat and diet utilization of the three species. Grayling were exclusively caught in shallow near-shore areas, feeding chiefly on surface insects and Trichoptera larvae. Whitefish dominated in all lake habitats, feeding predominantly on small-sized planktonic and benthic crustaceans. Arctic charr were mainly found along the benthic profile, feeding predominantly on insects and snails and showing a low dietary overlap with whitefish which appeared to have monopolised the zooplankton resources. The highly restricted trophic niche of Arctic charr suggests a severe competitive impact due to the presence of whitefish, but the coexistence of the two species may be facilitated by the presence of grayling.     

Environmental controls on benthic food web functions and carbon resource use in subarctic lakes

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Direct effects of warming increase woody plant abundance in a subarctic wetland

Both the direct effects of warming on a species’ vital rates and indirect effects of warming caused by interactions with neighboring species can influence plant populations. Furthermore, herbivory mediates the effects of warming on plant community composition in many systems. Thus, determining the importance of direct and indirect effects of warming, while considering the role of herbivory, can help predict long‐term plant community dynamics. We conducted a field experiment in the coastal wetlands of western Alaska to investigate how warming and herbivory influence the interactions and abundances of two common plant species, a sedge, Carex ramenskii, and a dwarf shrub, Salix ovalifolia. We used results from the experiment to model the equilibrium abundances of the species under different warming and grazing scenarios and to determine the contribution of direct and indirect effects to predict population changes. Consistent with the current composition of the landscape, model predictions suggest that Carex is more abundant than Salix under ambient temperatures with grazing (53% and 27% cover, respectively). However, with warming and grazing, Salix becomes more abundant than Carex (57% and 41% cover, respectively), reflecting both a negative response of Carex and a positive response of Salix to warming. While grazing reduced the cover of both species, herbivory did not prevent a shift in dominance from sedges to the dwarf shrub. Direct effects of climate change explained about 97% of the total predicted change in species cover, whereas indirect effects explained only 3% of the predicted change. Thus, indirect effects, mediated by interactions between Carex and Salix, were negligible, likely due to use of different niches and weak interspecific interactions. Results suggest that a 2°C increase could cause a shift in dominance from sedges to woody plants on the coast of western Alaska over decadal timescales, and this shift was largely a result of the direct effects of warming. Models predict this shift with or without goose herbivory. Our results are consistent with other studies showing an increase in woody plant abundance in the Arctic and suggest that shifts in plant–plant interactions are not driving this change.     

Porotic hyperostosis in a marine-dependent California Indian population

A maize-based iron- and protein-deficient diet is commonly cited as the most important cause of porotic hyperostosis among American Indian agriculturalists. An alternative to this maize dependence hypothesis is suggested by the analysis of 432 crania from the nonagricultural, fish-dependent population of the Channel Island area of southern California. Cribra orbitalia, a form of porotic hyperostosis associated with iron deficiency anemia, is just as common among these fisherpeople, whose diet was rich in iron and essential amino acids, as it is among maize-dependent agriculturalists. Northern Channel Island crania have much more cribra orbitalia than those from the California mainland. The highest incidence is on San Miguel, a small geographically isolated island with a shortage of fresh water and terrestrial resources. The Indians who lived on Santa Cruz, the largest of the northern Channel Islands with the greatest diversity of terrestrial plants and animals, have less cribra orbitalia than those who lived on Santa Rosa or San Miguel Island. This geographical distribution appears to be explained by island-mainland and interisland differences in water contamination, exposure to fish-borne parasites, and nutritional adequacy of the diet. The prevalence of porotic hyperostosis in a population with a heavy dietary dependence on marine resources shows that among prehistoric American Indians, this condition is not always associated with an iron- and protein-deficient diet of cultigens. It seems likely that high nutrient losses associated with diarrheal disease are often more significant in the etiology of porotic hyperostosis than a low dietary intake of essential nutrients.     

Ontogenetic niche shifts and resource partitioning in a subarctic piscivore fish guild

The feeding ecology of three piscivorous fish species (perch (Perca fluviatilis), pike (Esox lucius) and burbot (Lota lota)), was studied in the subarctic Pasvik watercourse (69 °N), northern Norway and Russia. All three species primarily occupied the benthic habitats in the watercourse. Perch and burbot exhibited distinct ontogenetic niche shifts in food resource use, perch changing from a dominance of zooplankton to zoobenthos to fish, and burbot from zoobenthos to fish. Fish prey dominated the diet of all the investigated size-classes of pike, but small-sized pike (<20 cm) were not represented in the sample. Fish prey size was positively related to predator size in all three species. Whitefish (Coregonus lavaretus) was the dominant prey of pike and large-sized burbot and perch. Nine-spined sticklebacks (Pungitius pungitius) was also an important prey and appeared to be a dietary stepping-stone enhancing the transition from invertebrate feeding to consumption of large-sized whitefish prey for all three predators. A cluster analysis separated the different size groups of the three predator species into five functional feeding groups, most of them containing two or all three species. Within these feeding groups, and especially among the piscivorous size-classes, there was a strong and significant interspecific overlap in prey selection, and the dietary similarities between the species were in general much larger than the intraspecific similarities between ontogenetic stages. All three piscivorous species are important top predators in the aquatic food web of the watercourse, and their ontogenetic diet shifts and resource partitioning patterns generate a substantial food web complexity in this subarctic ecosystem.     

Species removal and experimental warming in a subarctic tundra plant community

Neighbor interactions are likely to play an important role in subarctic plant communities. We conducted experiments in Interior Alaska in which we crossed species removal with greenhouse warming manipulations. We examined changes in community biomass, and in plant survival and growth of individual species in response to experimental warming and to: (1) removal of whole species versus an equivalent amount of biomass across many species, and (2) removal of subdominant (locally common) versus minor (locally uncommon) plants. Community biomass indicated compensation in growth after removal of minor species and after biomass removal without elimination of entire species, but under-compensation after removal of subdominants. Growth and survival of individual species showed facilitation between some species. Warming increased growth of dominant vascular plants, but at the same time reduced survival, and these impacts were greater for larger, more mesic species than for the smaller species associated with drier habitats. Growth of mosses was reduced by the warming. Removal effects did not differ between warming and ambient conditions. The results indicate that common species are able to reduce resources for others (competitive effect) and increase their growth after neighbor removal, whereas locally uncommon species are not able to respond rapidly to increased resources made available by neighbor removal. Therefore, the impact of the presence of common species on locally uncommon species was facilitative overall, but not vice versa. The balance between disturbances such as changes in temperature and species losses from the community will likely be crucial in determining shifts in subsequent community composition.     

Agricultural resource use in an andean coastal ecosystem

Five concurrent systems of agricultural resource management in the Viru Valley in Peru's arid northern coastal plain are discussed as adjustments to microenvironmental variations in soil humidity. Widespread dependence on canal irrigation in an environment characterized by uncertainty in the availability of river water affects the agrarian population in several ways. The upper socioeconomic class has adapted to uncertainty by implementing a deviation-counteracting mechanism (tubular wells) that provides water on demand, giving them flexibility in choice of agricultural activities. Another class of farmers is unable to introduce this mechanism, however, and consequently must depend on a repertoire of inflexible decisions to cope with uncertainty. Each group exploits different opportunity costs to increase economic gain. One pattern provides for expansion, whereas the other at best establishes stability and maintenance. Noncanal techniques permit expansion of cultivation in conditions where canal irrigation is not feasible, thereby improving the overall level of effectiveness of resource use. Alternative techniques do not involve regulatory mechanisms nor do they require complex, interlocking social, economic, and political components. Their presence and persistence in the agricultural system provide variation that may ultimately be amplified as the need to intensify resource exploitation increases in the future.     

海州湾鱼类群落平均营养级和大型鱼类指数的变化特征

为探究近年来海州湾鱼类群落的变化特征,本研究根据2011年及2013-2017年春季(5月)和秋季(9-10月)在海州湾及其邻近海域进行的渔业资源底拖网调查,分析了海州湾鱼类群落平均营养级(MTL)和大型鱼类指数(LFI),对海州湾鱼类群落结构特征进行研究.结果表明:海州湾的优势鱼种主要有大泷六线鱼、方氏云鳚、尖海龙、小黄鱼、长蛇鲻等,且优势鱼种季节性变化明显.海州湾鱼类群落的平均营养级存在明显的年际和季节变化,总体上秋季的MTL高于春季,而且秋季MTL变化具有滞后性.LFI计算结果表明,近年来海州湾及其邻近海域大个体鱼类资源量有所减少,鱼类群落结构呈现出明显的小型化趋势.     

Vegetation, climatic changes and net carbon sequestration in a North-Scandinavian subarctic mire over 30 years

This study deals with changes in the plant cover and its net carbon sequestration over 30 years on a subarctic Sphagnum-mire with permafrost near Abisko, northernmost Sweden, in relation to climatic variations during the same period. Aerial colour infrared images from 1970 and 2000 were compared to reveal changes in surface structure and vegetation over the whole mire, while the plant populations were studied within a smaller, mainly ombrotrophic part. The results demonstrated two processes, namely (1) that wet sites dominated by graminoids expanded while hummock sites dominated by dwarf shrubs receded, and (2) that on the hummocks lichens expanded while evergreen dwarf shrubs and mosses decreased, both processes creating an instability in the surface structure. A successive degradation of the permafrost is the likely reason for the increase in wet areas, while the changes in the hummock vegetation might have resulted from higher spring temperatures giving rise to an intensified snow melt, exposing the vegetation to frost drought. Because of the vegetation changes, the annual litter input of carbon to the mire has increased slightly, by 4 g m⁻² a⁻¹ (7.3%), over these years while an increased erosion has resulted in a loss of 40–80 Mg carbon or 7–17 g m⁻² a⁻¹ for the entire mire over the same period. As the recalcitrant proportion of the litter has decreased, the decay rate in the acrotelm might be expected to increase in the future.     

Inadequate community engagement hamstrings sustainable wildlife resource management in Zambia

We propose improvements for addressing the inadequate sustainable use of wildlife resources in the community-based natural resource management (CBNRM) programme in game management areas (GMAs) using case study data from Mumbwa and Lupande GMAs in Zambia. Firstly, we assess the sustainability of wildlife resources in these GMAs using design principles for enduring common pool institutions. Secondly, we propose the steps required to address the lack of sustainability of wildlife resources in the CBNRM programme in the two GMAs by building on indicators suggested by Ostrom's principles. The resource use patterns in the two GMAs were assessed according to their socio-economic and institutional factors. Comparisons were made between the two GMAs in relation to Ostrom's design principles. Accordingly, the combination of socio-economic and institutional factors restrains the sustainable use of wildlife resources in the two GMAs. Unless the Zambian government provides local communities with meaningful decision-making powers and benefits for the utilisation and management of wildlife, this resource is likely to disappear outside national parks.