Modeling as a complementary tool to acoustic data for understanding the impact of environmental disasters on marine mammals

2017 ◽  
Vol 142 (4) ◽  
pp. 2533-2533
Author(s):  
Azmy S. Ackleh ◽  
Ross Chiquet ◽  
Tingting Tang ◽  
Amy Veprauskas ◽  
Hal Cawell ◽  
...  
Author(s):  
Emma-Jane Goode ◽  
Eirian Thomas ◽  
Owen Landeg ◽  
Raquel Duarte-Davidson ◽  
Lisbeth Hall ◽  
...  

AbstractEvery year, numerous environmental disasters and emergencies occur across the globe with far-reaching impacts on human health and the environment. The ability to rapidly assess an environmental emergency to mitigate potential risks and impacts is paramount. However, collating the necessary evidence in the early stages of an emergency to conduct a robust risk assessment is a major challenge. This article presents a methodology developed to help assess the risks and impacts during the early stages of such incidents, primarily to support the European Union Civil Protection Mechanism but also the wider global community in the response to environmental emergencies. An online rapid risk and impact assessment tool has also been developed to promote enhanced collaboration between experts who are working remotely, considering the impact of a disaster on the environment and public health in the short, medium, and long terms. The methodology developed can support the appropriate selection of experts and assets to be deployed to affected regions to ensure that potential public health and environmental risks and impacts are mitigated whenever possible. This methodology will aid defensible decision making, communication, planning, and risk management, and presents a harmonized understanding of the associated impacts of an environmental emergency.


2020 ◽  
Author(s):  
Konstantina Agiadi ◽  
Niklas Hohmann ◽  
Giorgio Carnevale ◽  
Elsa Gliozzi ◽  
Constanza Faranda ◽  
...  

<p>The Messinian Salinity Crisis (MSC) was the greatest paleoenvironmental perturbation the Mediterranean has ever seen. The literature is abundant in hypotheses on the repercussions of the MSC on organisms. However, all these are based on incomplete and still uncertain scenarios about the MSC evolution, as well as on the assumption that such a paleoenvironmental perturbation must have completely reset marine biota. Having prevailed for many decades now, this assumption has leaked from paleontology and geosciences to biological sciences, with numerous studies taking this scenario for granted instead of using it as a starting hypothesis to be tested. Here, we review and revise the marine fossil record across the Mediterranean from the Tortonian until the Zanclean to follow the current rules of nomenclature, correct misidentifications, and control for stratigraphic misplacements. We examine the composition of marine faunas, both taxonomically and considering the function of each group in the marine ecosystem and the transfer of energy through the marine food web. Specifically, we investigate the following functional groups: 1) primary producers, 2) secondary producers, 3) primary consumers, 4) secondary consumers, and 5) top predators. Our study includes sea grasses, phytoplankton, corals, benthic and planktonic foraminifera, bivalves, gastropods, brachiopods, echinoids, bryozoans, fishes, ostracods, and marine mammals. We calculate biodiversity indexes to provide independent evidence quantifying to what degree the marine fauna underwent:</p><ol><li>A drop of overall regional biodiversity of the Mediterranean due to environmental stress during the Messinian.</li> <li>A taxonomic and functional change between the Tortonian, Messinian, and the Zanclean, that is before and after the MSC, as well as during the precursor events to that actual crisis taking place after the Tortonian/Messinian boundary.</li> <li>The onset of the present-day west-to-east decreasing gradient in species richness, which has been related to the sea temperature and productivity gradients and the distance from the Gibraltar connection to the Atlantic.</li> </ol>


<em>Abstract.</em>—Mexico is an important producer of fish resources, contributing 1.5% to the total world production. However, most of the fisheries are overexploited or fished to the maximum sustainable level as a result of problems such as overexploitation, poor infrastructure, poaching, limited knowledge of fishing laws, high discard rates, weak fisheries institutions, and little ability to research and manage these difficulties. To solve these problems, the National Program of Fisheries and Aquaculture was established in order to achieve sustainability in Mexican fisheries with the participation of the government, the fishing industry and research institutions. The program has been implemented for the 22 main fisheries of the country, notably the tuna, shrimp and shark fisheries, for which technical measures have been implemented for controlling the catch, the effort and the impact on coexisting species. Specifically, these measures have been aimed at reducing the bycatch of marine mammals and turtles, demersal and benthopelagic fishes and benthic invertebrates. Also, measures have been implemented to mitigate impacts of fishing gear on the benthos and coral reefs. However, many issues still need to be resolved both for these and other lower revenue fisheries, which are important in terms of their effect on ecosystems.


2020 ◽  
Vol 12 ◽  
Author(s):  
Ramon da Silva Raposo ◽  
Daniel Vieira Pinto ◽  
Ricardo Moreira ◽  
Ronaldo Pereira Dias ◽  
Carlos Alberto Fontes Ribeiro ◽  
...  

Worldwide environmental tragedies of anthropogenic origin causing massive release of metals and other pollutants have been increasing considerably. These pollution outbreaks affect the ecosystems and impact human health. Among those tragedies, recent large-scale environmental disasters in Brazil strongly affected riverside populations, leading to high-risk exposure to methylmercury (MeHg). MeHg is highly neurotoxic to the developing brain. This toxicant causes neural stem cell dysfunction and neurodevelopmental abnormalities. However, less is known about the effects of MeHg in the postnatal neurogenic niche, which harbors neural stem cells and their progeny, in the adult brain. Therefore, taking in consideration the impact of MeHg in human health it is urgent to clarify possible associations between exposure to mercury, accelerated cognitive decline, and neurodegenerative diseases. In this perspectives paper, we discuss the neurotoxic mechanisms of MeHg on postnatal neurogenesis and the putative implications associated with accelerated brain aging and early-onset cognitive decline in populations highly exposed to this environmental neurotoxicant.


2016 ◽  
Vol 283 (1844) ◽  
pp. 20162037 ◽  
Author(s):  
Zachary A. Schakner ◽  
Michael G. Buhnerkempe ◽  
Mathew J. Tennis ◽  
Robert J. Stansell ◽  
Bjorn K. van der Leeuw ◽  
...  

Socially transmitted wildlife behaviours that create human–wildlife conflict are an emerging problem for conservation efforts, but also provide a unique opportunity to apply principles of infectious disease control to wildlife management. As an example, California sea lions ( Zalophus californianus ) have learned to exploit concentrations of migratory adult salmonids below the fish ladders at Bonneville Dam, impeding endangered salmonid recovery. Proliferation of this foraging behaviour in the sea lion population has resulted in a controversial culling programme of individual sea lions at the dam, but the impact of such culling remains unclear. To evaluate the effectiveness of current and alternative culling strategies, we used network-based diffusion analysis on a long-term dataset to demonstrate that social transmission is implicated in the increase in dam-foraging behaviour and then studied different culling strategies within an epidemiological model of the behavioural transmission data. We show that current levels of lethal control have substantially reduced the rate of social transmission, but failed to effectively reduce overall sea lion recruitment. Earlier implementation of culling could have substantially reduced the extent of behavioural transmission and, ultimately, resulted in fewer animals being culled. Epidemiological analyses offer a promising tool to understand and control socially transmissible behaviours.


2015 ◽  
Vol 72 (5) ◽  
pp. 1637-1652 ◽  
Author(s):  
Cecilia Passadore ◽  
Andrés Domingo ◽  
Eduardo R. Secchi

Abstract Bycatch is one of the main causes of human-caused mortality and population decline of many marine mammals. Monitoring bycatch is the first step to understand the impact of the fisheries on the species affected. Understanding how the interaction between marine mammals and fishing operations varies in space and time, and how it is influenced by environmental variables, is essential for designing mitigation strategies to reduce bycatch mortality. In this paper, we use data gathered by scientific observers and a fishing skipper to analyse marine mammals bycatch by the Uruguayan pelagic longline fishery operating in the Southwestern Atlantic Ocean from 1996 to 2007. The total bycatch per unit effort (Bcpue) was 0.0150 marine mammals/1000 hooks and the highest values (∼0.2) were recorded between 37°–38°S and 49°–51°W. Total cetacean Bcpue during the study period was low (0.0051 cetacean/1000 hooks) and occurred between 32°–37°S and 46°–54°W. Generalized additive models showed that cetaceans' bycatch was mainly affected by the depth, sea surface temperature, and season. Although cetaceans were captured year-round, the highest values were registered in spring months, most bycatch events occurred over the continental slope (median = 619 m) and in waters with a median temperature of 19.7°C. The bycatch of pinnipeds was influenced by depth, location, and season. Pinniped bycatch occurred mainly in winter, in waters ranging from 80 to 5000 m of depth (median = 2366 m) between 34°–37°S (median = 35.9°S) and 54°–49°W (median = 51.8°W). The spatial analysis showed that most bycatch events occurred within the Brazil–Malvinas Confluence zone, an area of high productivity where the pelagic longline fleet concentrates its fishing effort and where marine mammals probably concentrate to feed.


2013 ◽  
Vol 19 (1) ◽  
pp. 19 ◽  
Author(s):  
E Martinez ◽  
K A Stockin

While coastal cetaceans can become habituated to watercraft, that may not prevent their injury or mortality as a consequence of vessel strike. Here we report a case of a likely collision between a Common Dolphin Delphinus sp. and a recreational vessel in the Hauraki Gulf, New Zealand. Injuries sustained by the immature male dolphin were fatal. Recovery and subsequent post-mortem of the carcass revealed a transection of the spinal cord, with the vertebral column sustaining fractures between L17 and Cd7 and between Cd3 and Cd8 of the neural and transverse processes, respectively. Cd4 likely received the brunt of the impact given the vertebral body and epiphyses were also fractured. Paralysis of the lower truck and associated extensive internal injuries resulted in a live stranding and subsequent mortality. Injuries sustained were consistent of those of blunt force trauma, a consequence of an impact caused by a collision with a small watercraft, most likely a jet-ski. This incident reinforces the need for continued public education concerning safe water practices around marine mammals, which are protected under the New Zealand Marine Mammals Protection Act 1978 and Marine Mammals Protection Regulations 1992.


2002 ◽  
Vol 24 (1) ◽  
pp. 85 ◽  
Author(s):  
LJ Boren ◽  
NJ Gemmell ◽  
KJ Barton

Marine mammals are significant tourist attractions around New Zealand, however, the impact of eco-tourism on these species is poorly documented. Effective management to mitigate any negative effects requires an understanding of target species? reactions to tourist activities. We have studied the effects of tourist activities on New Zealand fur seals (Arctocephalus forsteri) using a novel combination of observations and controlled approaches. Three study areas were selected reflecting a range of visitor density, type of tourism, and the anticipated sensitivity of fur seals to disturbance. Behaviour was observed using instantaneous scan sampling and attributes of tourist approaches were tested experimentally by controlled approaches. Approaches were made on land, by kayak, and motorboat. Fur seal responses and the distance at which the seal responded were recorded. Our results indicate that A. forsteri behaviour was being modified by tourist activities. Habituation was occurring at study areas with high levels of tourist activity. Approachers following current minimum approach distances still caused some animals to modify their behaviour and new minimum approach distances are recommended based on controlled approaches to seals at all study areas. Our work demonstrated that controlled approaches can be a useful tool to develop effective management guidelines to lessen impacts from eco-tourism activities.


PLoS ONE ◽  
2015 ◽  
Vol 10 (3) ◽  
pp. e0118113 ◽  
Author(s):  
Marta Söffker ◽  
Phil Trathan ◽  
James Clark ◽  
Martin A. Collins ◽  
Mark Belchier ◽  
...  

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