A critical sites network for freshwater biodiversity in the Lake Victoria Basin

The Lake Victoria Basin (LVB) is known for its high levels of species richness and endemism. Freshwater ecosystems within this region are highly threatened, putting both biodiversity and human livelihoods at risk. Protected areas (PAs) should provide the foundation for conservation actions to tackle threats but currently poorly represent freshwater species. To address this issue, systematic conservation planning (Marxan) was used to identify networks of sites within the LVB for the conservation of freshwater biodiversity, based on existing Key Biodiversity Areas (KBAs) and PAs, and with minimal cost in terms of area and human impact. Networks were identified separately for threatened species and/or those endemic to the LVB, and those susceptible to the impacts of climate change. Here, these were combined to present an overall sites network for the conservation of freshwater biodiversity. Site‐level recommendations are provided as a scientific basis for the development and expansion of the existing network.     

An unexpected host for the endangered giant freshwater pearl mussel Margaritifera auricularia (Spengler, 1793) as a conservation tool

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Response of Scotian Shelf silver hake (Merluccius bilinearis) to environmental variability

Commercially‐exploited fish populations are not only shaped by fishing pressure, but also by the dynamics of their environment. By quantifying the influence of environmental variability, fisheries management advice can be improved and uncertainties reduced. To this end, we developed statistical models of the response of Scotian Shelf silver hake stock metrics to variability in zooplankton community composition and phenology over the past 18 years and in the physical environment since 1985. Dominant modes of variability in these pelagic habitat indicators were characterized using principal component analysis, and the relationships of silver hake condition, abundance, and recruitment to pelagic habitat variability were assessed using generalized additive models. Condition was largely modulated by the onset and duration of the spring bloom, which controls food availability. In contrast, adult abundance was governed by composition of the zooplankton community and bottom‐water temperature, which dictates the distribution of silver hake. Finally, recruitment was affected by both thermal conditions and food availability. Our results presented here form the basis for qualitative assessment of ecosystem attributes and the influence on silver hake stock productivity.     

Differing trophic niches of three French stygobionts and their implications for conservation of endemic stygofauna

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Ecosystems say good management pays off

Understanding the strengths and weaknesses of alternative assessment methods, harvest strategies and management approaches are an important part of operationalizing single‐species and ecosystem‐based fisheries management. Simulations run using two variants of a whole‐of‐ecosystem model for the Southern and Eastern Scalefish and Shark Fishery (SESSF) area shows that (a) data‐rich assessments outperform data‐poor assessments for target species and that this performance is reflected in the values of many system‐level ecosystem indicators; (b) ecosystem and multispecies management outperforms single‐species management applied over the same domain; (c) investment in robust science‐based fisheries management pays dividends even when there are multiple jurisdictions, some of which are not implementing effective management; and (d) that multispecies yield‐oriented strategies can deliver higher total catches without a notable decline in overall system performance, although the resulting system structure is different to that obtained with other forms of ecosystem‐based management.     

Relationships between agroforestry and community development according to practitioners

Post-adoption studies are relatively uncommon in the agroforestry literature. Thus little is known about progress and permanence following adoption. To better understand the relationship between agroforestry implementation and community development, seventy-seven practitioners in Cameroon with three or more years of experience were surveyed about the relationships between agroforestry and community development. Hypotheses were that they have observed differences in the association between agroforestry and community capitals. They were also surveyed about their satisfaction with agroforestry. Hypotheses were that satisfaction is high and negatively skewed when compared to community capitals measurements. Game play was used to collect responses. Friedman’s two-way non-parametric statistic was used to test for inter-item differences within the community capitals and satisfaction response sets. Shapiro–Wilk statistic was used to test for normality in both response sets and a bootstrap procedure and t-tests were used to test for differences in data skewness and kurtosis. Natural capital scored highest but did not differ significantly from built, human, and social capitals. Financial capital was significantly lower than natural capital, but not built, human, or social capitals. Political and cultural capitals were significantly lower compared to all others. Satisfaction was significantly higher when compared to community capitals, but the data were also negatively skewed suggesting capitals are a more representative and useful metric for researchers and technical assistance professionals focused on long-term practitioner support.     

Partial replacement of soybean meal with Methylobacterium extorquens single‐cell protein in feeds for rainbow trout (Oncorhynchus mykiss Walbaum)

A feeding trial was conducted with juvenile rainbow trout (15–16 g initial weight) to assess the effects of including single‐cell protein (SCP) produced from Methylobacterium extorquens in trout feeds. Three isonitrogenous and isoenergetic diets were produced: a control diet and two experimental diets containing 5% or 10% bacterial protein meal replacing soybean meal. Triplicate tanks, each containing 35 fish, were fed each diet to apparent satiation in a constant‐temperature (15°C), flow‐through tank system for 12 weeks. No statistically significant differences in final fish weight or other fish growth parameters were observed. Similarly, feed efficiency parameters showed no significant differences among groups. Nutrient retention indices (protein, fat, energy) were relatively high and similar among fish in each dietary treatment group, as were whole body proximate compositions. Fish survival was high, with a small but statistically significant increase for the 10% SCP diet. Overall, results demonstrate that SCP from M. extorquens is a safe and effective alternative protein for rainbow trout diets at the low inclusion levels tested. Slightly lower weight gain in fish fed the 10% SCP diet was largely due to lower feed intake, suggesting that adding palatability‐enhancing ingredients to feeds may allow higher levels of M. extorquens SCP to be used without compromising fish growth.     

Vegetative propagation of twelve fodder tree species indigenous to the Sahel,West Africa

In the Sahel region, many woody species are used as fodder because of their high nitrogen content, especially during the dry season, in contrast to grasses and crop residues. Unfortunately, this resource is being threatened by regular pruning, increasing livestock browsing and impeding their natural regeneration. Therefore, there is a need to find appropriate regeneration options to sustain fodder production. Thus, a series of vegetative propagation experiments were conducted to identify the most appropriate multiplication methods of some of the species used as fodder. This series included testing the effects of naphthalene acetic acid (NAA) and indole butyric acid (IBA) on rooting ability of stem cuttings of 12 species: Afzelia africana, Balanites aegyptiaca, Bauhinia rufescens, Commiphora africana, Faidherbia albida, Ficus gnaphalocarpa, Guiera senegalensis, Kigelia africana, Pterocarpus erinaceus, Pterocarpus lucens, Pterocarpus santalinoides and Terminalia avicennioides. The series also evaluated the impacts of the size (C. africana) and the age (P. erinaceus) of the cuttings on their rooting success. Pterocarpus santalinoides was revealed to be an easy-to-root species, showing a high percentage of rooted cuttings (up to 88±3%), followed by P. erinaceus, P. lucens and B. aegyptiaca (up to 37±4%, 31±5% and 26±6%, respectively), in contrast to A. africana, cuttings of which did not root at all. The application of NAA and IBA enhanced the number of roots and secondary roots per rooted cutting. Large-diameter cuttings (15–20?mm) of deeply planted C. africana gave the highest percentage of rooted cuttings (78.3±4.4%). Tree pruning improved the rooting capacity of cuttings collected from P. erinaceus with one-month resprouts giving the highest percentage of rooted cuttings (50.0±6.7%). These results indicate that P. santalinoides, C. africana, P. erinaceus, P. lucens and B. aegyptiaca are amenable to vegetative propagation as an alternative to sexual propagation.     

Biocultural Diversity of Sarangani Province,Philippines: An Ethno-Ecological Analysis

This paper discussed effects of lowland-associated influences on upland ecology, food security and biocultural diversity in the Sarangani farming communities of the Philippines. In the uplands of Sarangani Province, the conservation of traditional rice varieties, the centrality of rice in tribal life, and the continued observance of planting rituals attest to its cultural significance and convey a common desire for cultural preservation and community solidarity. Economic and socio-political pressures had transformed tribal communities, although vestiges of traditional farming systems are still being practiced in remote sitios(villages). Changing land use patterns had also resulted in shrinking farm sizes and consequently in food insecurity in the Sarangani uplands. Extractive industries(i.e. logging, mining and charcoal making) and swidden farming were observed to cause widespread environmental degradation, while modern agriculture had undermined the capacity of indigenous peoples to survive because of their complete dependence on lands and resources. With the reality that cultural and biological diversities are inextricably linked, trans-disciplinary strategies coupling indigenous knowledge systems with scientific knowledge should, therefore, be instituted to save the Sarangani upland ecosystem, the indigenous peoples and their tribal resources.