Bioaccumulation of polybrominated diphenyl ethers in harbor seals from the northwest Atlantic

Polybrominated diphenyl ethers (PBDEs) were analyzed in blubber of harbor seals (Phoca vitulina concolor) collected between 1991 and 2005 along the northwest Atlantic. ∑PBDE concentrations (mono- to hexa-BDEs) detected in blubber samples (n = 42) ranged from 80 to 25 720 ng g⁻¹ lw, (overall mean 2403 ± 5406 ng g⁻¹ lw). By age, mean ∑PBDE concentrations were: 3645 ± 7388, 2945 ± 5995, 1385 ± 1265, and 326 ± 193 ng g⁻¹ lw in pups, yearlings, adult males, and adult females, respectively. Unlike the trend for PCBs, no decreasing gradient from urban to rural/remote areas was observed for PBDEs in these samples, likely reflecting inputs from local sources. No significant temporal trend was observed for PBDEs in harbor seals between 1991 and 2005, although congener profiles shifted over time. Tetra-BDE-47 was the dominant congener, followed by BDEs-99, -100, -153, -154, and -155 in varying order, suggesting exposure to the penta-BDE product. In adult males, the hexa-BDEs contributed more to the total (22%) than BDEs-99 and -100 (14%), and concentrations of BDE-155 were elevated compared with -154. Higher BDEs were detected in a subset of seals (n = 12) including hepta-BDE-183, the marker for the octa-BDE mixture, and octa-BDE-197, along with several unidentified hepta- and octa- congeners. BDE-209 was detected in seal blubber at concentrations ranging from 1.1 to 8 ng g⁻¹ lw, indicating that deca-BDE is bioavailable in this marine food web. This is the first study to document the accumulation of BDE-209 at measurable levels in wild harbor seals. While the PBDE patterns in blubber indicate exposure to all three BDE commercial mixtures, the data also suggest that BDE-209 debromination by seal prey fish may contribute to the loading of lower brominated congeners (hexa- to octa-BDEs) in these seals.     

A model-based assessment of the environmental impact of land-use change across scales in Southern Amazonia

Regional Environmental Change - This article describes the design of a new model-based assessment framework to identify and analyse possible future trajectories of agricultural development and...     

Correction to: Can preferential credit programs speed up the adoption of low-carbon agricultural systems in Mato Grosso,Brazil? Results from bioeconomic microsimulation

Regional Environmental Change - The published online version contains incorrect data in Figure 7.     

Common frogs response to agrochemicals contamination in coffee plantations,Western Ghats,India

This study highlights the health status of frogs in coffee plantations of Western Ghats. Coffee is one of the major commercial crops in the Western Ghats of India. In these plantations, farmers extensively use agrochemicals including pesticides and synthetic fertilisers. The practice of agrochemical usage can negatively affect non-target organisms like amphibians. The area has reported many amphibian species living in and around plantations. A total of 334 frogs from reference sites (10 abnormal frogs) and a total of 258 frogs (19 abnormal frogs) were collected from contaminated sites. We considered major biomarkers like hepato-somatic index, gonado-somatic index, morphological abnormalities and acetylcholinestarse activities for evaluating the health status of frogs. In our study, the hepato-somatic index and gonado-somatic index were found to be higher in a grochemical contaminated sites. Whereas, acetycholine esterase activity in brain and liver tissues of frogs in contaminated sites were low compared to reference sites. High rate of incidence of morphological abnormality (7.36%), increased hepato-somatic index (14.86%) and gonado-somatic index (male; 8.88% and female; 17.51%) and low acetylcholine esterase activities in brain (41.5%) and liver (46.9%) indicates the lower health status of frogs living in coffee plantations that are regularly treated with agrochemicals.     

A systematic survey of the integration of animal behavior into conservation

The role of behavioral ecology in improving wildlife conservation and management has been the subject of much recent debate. We sought to answer 2 foundational questions about the current use of behavioral knowledge in conservation: To what extent is behavioral knowledge used in wildlife conservation and management, and how does the use of animal behavior differ among conservation fields in both frequency and types of use? We searched the literature for intersections between key fields of animal behavior and conservation and created a systematic heat map (i.e., graphical representation of data where values are represented as colors) to visualize relative efforts. Some behaviors, such as dispersal and foraging, were commonly considered (mean [SE] of 1147.38 [353.11] and 439.44 [108.85] papers per cell, respectively). In contrast, other behaviors, such as learning, social, and antipredatory behaviors were rarely considered (mean [SE] of 33.88 [7.62], 44.81 [10.65], and 22.69 [6.37] papers per cell, respectively). In many cases, awareness of the importance of behavior did not translate into applicable management tools. Our results challenge previous suggestions that there is little association between the fields of behavioral ecology and conservation and reveals tremendous variation in the use of different behaviors in conservation. We recommend that researchers focus on examining underutilized intersections of behavior and conservation themes for which preliminary work shows a potential for improving conservation and management, translating behavioral theory into applicable and testable predictions, and creating systematic reviews to summarize the behavioral evidence within the behavior‐conservation intersections for which many studies exist.     

Indirect effects of African megaherbivore conservation on bat diversity in the world's oldest desert

In extreme environments, temperature and precipitation are often the main forces responsible for structuring ecological communities and species distributions. The role of biotic interactions is typically thought to be minimal. By clustering around rare and isolated features, like surface water, however, effects of herbivory by desert-dwelling wildlife can be amplified. Understanding how species interact in these environments is critical to safeguarding vulnerable or data-deficient species. We examined whether African elephants (Loxodonta africana), black rhinoceros (Diceros bicornis), and southern giraffe (Giraffa giraffa) modulate insectivorous bat communities around permanent waterholes in the Namib Desert. We estimated megaherbivore use of sites based on dung transects, summarized vegetation productivity from satellite measurements of the normalized difference vegetation index, and surveyed local bat communities acoustically. We used structural equation models to identify relationships among megaherbivores and bat species richness and dry- (November 2016–January 2017) and wet- (February–May 2017) season bat activity. Site-level megaherbivore use in the dry season was positively associated with bat activity—particularly that of open-air foragers—and species richness through indirect pathways. When resources were more abundant (wet season), however, these relationships were weakened. Our results indicate that biotic interactions contribute to species distributions in desert areas and suggest the conservation of megaherbivores in this ecosystem may indirectly benefit insectivorous bat abundance and diversity. Given that how misunderstood and understudied most bats are relative to other mammals, such findings suggest that managers pursue short-term solutions (e.g., community game guard programs, water-point protection near human settlements, and ecotourism) to indirectly promote bat conservation and that research includes megaherbivores’ effects on biodiversity at other trophic levels.     

Consecutive geoelectric measurements reveal the downward movement of an oxidation zone

An investigation program for monitoring pyrite oxidation on a conveyer bridge dump used geoelectric measurement for monitoring the progress of pyrite oxidation within the dump. The results of the geoelectric measurement show that low soil-pH and high pore water conductivity correlate with low soil resistivity values. The soil resistivity values are dominated by high pore water conductivity. The influence of changes in water saturation on resistivity was comparably low. An increase in pyrite oxidation was observed in areas with high porosity due to low dump density. Consecutive geoelectric measurements revealed locally differentiated downward movement of an oxidation zone caused by dump heterogeneity.