Annotated checklist and fisheries interactions of cetaceans in Togo,with evidence of Antarctic minke whale in the Gulf of Guinea

Based on strandings and captures, 9 cetacean species, including 6 odontocetes and 3 mysticetes, are documented (photos and specimens) in Togo's coastal waters (newly‐recorded species marked with an asterisk): Antarctic minke whale (Balaenoptera bonaerensis*), Bryde's whale (Balaenoptera brydei or B. edeni), humpback whale (Megaptera novaeangliae), sperm whale (Physeter macrocephalus), pygmy sperm whale (Kogia breviceps*), short‐finned pilot whale (Globicephala macrorhynchus*), pantropical spotted dolphin (Stenella attenuata*), common bottlenose dolphin (Tursiops truncatus) and common dolphin Delphinus sp. An anecdotal sighting record for killer whale (Orcinus orca) is considered reliable. The lack of Sousa teuszii records in Togo is consistent with its apparent contemporaneous absence in Ghana. The B. bonaerensis specimen, entangled in a purse seine set on small pelagics, is a first record for the Gulf of Guinea. The occurrence of this Southern Ocean species north of the equator underscores the severe gaps in our understanding of cetacean distribution off western Africa. The majority of artisanal fishermen operating in Togolese coastal waters are of Ghanaian origin and are thought to promote trade and consumption of cetacean bushmeat. Because captures are illegal, enforced with some success in the main fishing centers, covert landings of cetaceans are exceedingly difficult to monitor, quantify or sample. Concern is expressed about pollution of Togo's coastal waters with heavy metals due to phosphorite mining and export from the coastal basin near Hahotoé and Kpogamé.     

Assessment of the antihistomonal effect of paromomycin and tiamulin

Histomonosis, a parasitic disease of galliformes and sporadically of other birds caused by Histomonas meleagridis, can result in very high mortality, especially in turkeys. The ban on the last antihistomonal drug prompted an urgent search for alternative prevention and treatment strategies. As both paromomycin and tiamulin have been reported to have antihistomonal activity, these antibiotics were investigated in vitro by adding two-fold serial dilutions ranging from 12.5 to 400 microg/mL to cultures of H. meleagridis. Controls (no antibiotics, or 12.5 microg or 400 microg/mL dimetridazole) were included. Parasites were counted after 3, 20, 28, 44, 51, and 71 hours of incubation. Tiamulin did not have a clear antihistomonal effect, but paromomycin had an inhibitory effect at all concentrations tested. The latter antibiotic was subsequently examined in an in vivo study. Five groups of 20 1-day-old poults, matched by weight and sex, were either not treated (infected and uninfected control groups) or treated with paromomycin (100, 200, or 400 ppm) added to their feed. After 2 weeks all groups, except for the uninfected control group, were intracloacally inoculated with 200,000 histomonads per bird. A clear dose-response effect was found for paromomycin. In the 100-ppm paromomycin group, mortality was similar to that in the untreated control group, whereas about half of the birds died in the 200-ppm paromomycin group; almost complete protection against histomonosis was seen in the 400-ppm paromomycin group. This study shows that paromomycin supplied in feed at 400 ppm is a potentially preventive strategy against H. meleagridis.     

The representativeness of protected areas for Amazonian fish diversity under climate change

1. The Amazon basin has been subjected to extreme climatic events and according to climate change projections this hydrosystem could face changes in the natural dynamic of flood cycles that support the feeding and reproduction of many fish species, threatening aquatic biodiversity.
2. Protected areas (PAs) are the main tools used to safeguard the biodiversity in the long term; however, they are fixed areas that could be subject to climate change, questioning their future efficiency in protecting biodiversity.
3. The Amazon basin currently benefits from a relatively high level of protection as 52% of its catchment area is under the form of true PAs or indigenous lands. However, the capacity of these PAs to protect freshwater biodiversity remains unclear as they have generally been assessed with little regard to freshwater ecosystems and their hydrological connectivity. Here, the aim was to evaluate the effectiveness of PAs in representing the Amazon fish fauna under current and future climatic conditions.
4. A macroecological approach was used to estimate the minimum size of the geographical range needed by each species to achieve long-term persistence, by a combined function of range size and body size, two ecological traits known to influence species extinction risk.
5. In future the Amazon basin could risk losing 2% of its freshwater fish fauna owing to unsuitable climatic conditions, with a further 34% adversely affected. The present Amazon network of PAs will cover the minimum required range for species persistence for more than 60% of the freshwater fish species analysed under the future climate scenario. However, more than 25% of the future susceptible species are currently concentrated in large tributaries and in the central-lower Amazon floodplain where few PAs occur, highlighting the lack of appropriate conservation actions for these specific water bodies.

     

Scaling issues in forest ecosystem management and how to address them with models

Scaling is widely recognized as a central issue in ecology. The associated cross-scale interactions and process transmutations make scaling (i.e. a change in spatial or temporal grain and extent) an important issue in understanding ecosystem structure and functioning. Moreover, current concepts of ecosystem stewardship, such as sustainability and resilience, are inherently scale-dependent. The importance of scale and scaling in the context of forest management is likely to further increase in the future because of the growing relevance of ecosystem services beyond timber production. As a result, a consideration of processes both below (e.g. leaf-level carbon uptake in the context of climate change mitigation) and above (e.g. managing for biodiversity conservation at the landscape scale) the traditional focus on the stand level is required in forest ecosystem management. Furthermore, climate change will affect a variety of ecosystem processes across scales, ranging from photosynthesis (tree organs) to disturbance regimes (landscape scale). Assessing potential climate change impacts on ecosystem services thus requires a multi-scale perspective. However, scaling issues have received comparatively little attention in the forest management community to date. Our objectives here are thus first, to synthesize scaling issues relevant to forest management and second, to elucidate ways of dealing with complex scaling problems by highlighting examples of how they can be addressed with ecosystem models. We have focused on three current management issues of particular importance in European forestry: (1) climate change mitigation through carbon sequestration, (2) multi-functional stand management for biodiversity and non-timber goods and services and (3) improving the resilience to natural disturbances. We conclude that taking into account the full spatiotemporal heterogeneity and dynamics of forest ecosystems in management decision-making is likely to make management more robust to increasing environmental and societal pressures. Models can aid this process through explicitly accounting for system dynamics and changing conditions, operationally addressing the complexity of cross-scale interactions and emerging properties. Our synthesis indicates that increased attention to scaling issues can help forest managers to integrate traditional management objectives with emerging concerns for ecosystem services and therefore deserves more attention in forestry.     

定向释放理念在家禽饲料中的应用

了解鸡胃肠道解剖学、生理学和功能对实现最佳的营养功效极为重要。本文我们将讨论有关使用一种含被包型丁酸、短链及长链脂肪酸和植物制剂的产品来解决家禽肠道问题的新思路。