In this study, we investigate association patterns of 249 bottlenose dolphin feeding groups off Sardinia Island (Italy) from
January 2000–May 2007 and describe how their association behaviour is related to their response to food patches created by
a marine fin fish farm. We also tested the hypothesis that dolphins have different social structures with different feeding
activities: Associations should decrease during opportunistic feeding behaviours as it is easier to capture prey, and cooperation
is not as necessary. Sixteen individually identified bottlenose dolphins were observed participating in both opportunistic
and not opportunistic feeding activities, with a mean of 30 ± 8 times and 9.6 ± 1 times, respectively. Bottlenose dolphins
show non-random social behaviour during feeding and this behaviour differs depending on their specific foraging activity.
Dolphin associations during feeding can be divided into three categories: acquaintances, affiliates, and feeding associates.
Association behaviour during fish farm feeding is consistent with our hypothesis that during opportunistic behaviours, benefits
from cooperation decrease, as it is easier to capture prey. Group size homogeneity in both feeding activities demonstrates
that the number of dolphins engaging in foraging is not necessarily related with cooperation levels. Moreover, an adult dolphin
may prefer to associate with a specific individual, independent of the sex, who shares the same foraging priorities. This
study is the first to show how aquaculture is not only directly affecting marine predators but could also indirectly affect
their social structure and behaviour. 相似文献
Environmental Science and Pollution Research - Phthalates are micro-pollutants of great concern due to their negative effects on ecosystem functioning and human health. Thanks to its capability in... 相似文献
Environmental Science and Pollution Research - The study of the soil microbial community represents an important step in better understanding the environmental context. Therefore, biological... 相似文献
Modern agriculture is dependent on phosphate rock (PR), which is a nonrenewable resource. Improvement of phosphorus (P) availability for crops in agricultural soils represents a key strategy to slow down the depletion of PR. The aim of this study was to identify potential P biofertilisers among saprotrophic fungal species. We tested 30 fungal strains belonging to 28 taxa (4 Zygomycota and 24 Ascomycota) and with different life strategies. The study showed that many saprotrophic fungi have the ability to mobilise P from insoluble forms according to a variety of mechanisms. Our results expand the pool of P solubilising fungal species, also suggesting a new solubilisation index and shedding light on parameters that could be basic in the selection of efficient soil P-biofertilisers fungi. Rhizopus stolonifer var. stolonifer, Aspergillus niger and Alternaria alternata were found to be the best performing strains in terms of amounts of TCP solubilisation. 相似文献
The impact of Hurricane Sandy on the Hudson-Raritan estuary (HRE) provided a valuable case study for exploring interactions between long-term environmental degradation, new climatic disturbance stressors, and human behavioral responses. We extend previous research on the ecological effects of major storms to compare water quality and biological parameters three years before and three years after Hurricane Sandy and consider how ecosystem shifts relate to anglers’ perceptions. Results indicate that water clarity and nutrients returned to pre-storm conditions in about one year, while shifts in the biological community, including a significant increase in harmful algal species and declines in zooplankton and Atlantic menhaden, persisted for multiple years, and anglers continued to fish amidst ecosystem decline. Biotic recovery time in the HRE was longer than reports for other shallow estuaries frequently disturbed by hurricanes. Ecological and social responses suggest that the post-storm regime shifts and continued fishing pressure could further environmental degradation. 相似文献
Increasing discussion over the safety of natural resource extraction and transportation to facilitate international energy needs has given rise to controversy over the prospect of large quantities of bitumen and crude oil flowing through trans-national pipelines. This debate, incorporating the voices of industry, government and advocacy groups, has gained traction in the news media, alternately framed as an environmental, economic, trade, human rights or public safety concern. It is possible, however, that such coverage may vary substantially with regional interests and perceptions of costs and benefits, locally or nationally. To uncover how the framing of energy transportation varies with proximity considerations, regional and national media coverage in Canada and the United States of the Keystone XL pipeline from 2010 to 2014 is analyzed. National and local papers frame the pipeline according to different considerations, as do cities near to and distant from the pipeline route. 相似文献
Objective: Understanding pedestrian injury trends at the local level is essential for program planning and allocation of funds for urban planning and improvement. Because we hypothesize that local injury trends differ from national trends in significant and meaningful ways, we investigated citywide pedestrian injury trends to assess injury risk among nationally identified risk groups, as well as identify risk groups and locations specific to Baltimore City.
Methods: Pedestrian injury data, obtained from the Baltimore City Fire Department, were gathered through emergency medical services (EMS) records collected from January 1 to December 31, 2014. Locations of pedestrian injuries were geocoded and mapped. Pearson's chi-square test of independence was used to investigate differences in injury severity level across risk groups. Pedestrian injury rates by age group, gender, and race were compared to national rates.
Results: A total of 699 pedestrians were involved in motor vehicle crashes in 2014—an average of 2 EMS transports each day. The distribution of injuries throughout the city did not coincide with population or income distributions, indicating that there was not a consistent correlation between areas of concentrated population or concentrated poverty and areas of concentrated pedestrian injury. Twenty percent (n = 138) of all injuries occurred among children age ≤14, and 22% (n = 73) of severe injuries occurred among young children. The rate of injury in this age group was 5 times the national rate (Incident Rate Ratio [IRR] = 4.81, 95% confidence interval [CI], [4.05, 5.71]). Injury rates for adults ≥65 were less than the national average.
Conclusions: As the urban landscape and associated pedestrian behavior transform, continued investigation of local pedestrian injury trends and evolving public health prevention strategies is necessary to ensure pedestrian safety. 相似文献
Hydraulic fracturing, or fracking, is a controversial but popular method of extracting oil and gas in North America. There are a myriad of completing claims about the economic benefits and the environmental costs of the technology. This paper examines news media coverage of fracking in four Canadian and four American newspapers over a five-year period. A comparison is made at the national level as well as at a paired subnational level between jurisdictions where fracking is embraced and where fracking is banned. The paper demonstrates that in both countries the main storyline is about water quality, but beyond that differences emerge as Americans focus more on wildlife and public health and Canadians focus more on moratoriums and energy independence. Moreover, while there were similarities in media coverage of fracking in pro-fracking and anti-fracking jurisdictions, there were notable differences in attention to the topics of public health and economic benefits. 相似文献
Although the literature is increasingly concerned with cooperation among humanitarian non-governmental organisations (NGOs), we still lack studies that explain cooperation under conditions of competition. Drawing on 22 semi-structured interviews, this article argues that trust is the driving force behind security-related cooperation within networks of humanitarian NGOs. Which type of trust comes into play and how trust is built depends on the structure of a network. In small, stable networks, trust is typically based on experience, whereas shared identity is at the heart of trust in large, unstable networks. In the latter case, cooperation among humanitarian NGOs is exclusive and comparable to a form of club governance, because NGOs are kept out based on their identity—that is, if they adopt a different operational interpretation of the humanitarian principles. 相似文献