Literature Library

Currently indexing 7759 titles

Community-level facilitation by macroalgal foundation species peaks at an intermediate level of environmental stress

Scrosati RA. Community-level facilitation by macroalgal foundation species peaks at an intermediate level of environmental stress. ALGAE [Internet]. 2017 ;32(1):41 - 46. Available from: https://www.e-algae.org/journal/view.php?doi=10.4490/algae.2017.32.2.20
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

In rocky intertidal habitats, abiotic stress due to desiccation and thermal extremes increases with elevation because of tides. A study in Atlantic Canada showed that, at low elevations where conditions are benign due to the brief low tides, fucoid algal canopies (Ascophyllum nodosum and Fucus spp.) do not affect the structure of benthic communities. However, at middle and high elevations, where low tides last longer, fucoid canopies limit abiotic extremes and increase the richness (number of invertebrate and algal species, except fucoids) of benthic communities. Using the data from that study, this paper compares the intensity of facilitation and its importance (relative to all other sources of variation in richness) between middle and high elevations, which represent intermediate and high stress, respectively. Facilitation intensity was calculated as the percent increase in benthic richness between quadrats with low and high canopy cover, while the importance of facilitation was calculated as the percentage of variation in richness explained by canopy cover. Data for 689 quadrats spanning 350 km of coastline were used. Both the intensity and importance of facilitation were greater at middle elevations than at high elevations. As canopies do not affect benthic communities at low elevations, this study suggests that the facilitation-stress relationship at the community level is unimodal for this marine system. Such a pattern was found for some terrestrial systems dominated by canopy-forming plants. Thus, it might be ubiquitous in nature and, as further studies refine it, it might help to predict community-level facilitation depending on environmental stress.

Unimodal relationship between small-scale barnacle recruitment and the density of pre-existing barnacle adults

Scrosati RA, Ellrich JA. Unimodal relationship between small-scale barnacle recruitment and the density of pre-existing barnacle adults. PeerJ [Internet]. 2017 ;5:e3444. Available from: https://peerj.com/articles/3444/
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Recruitment is a key demographic process for population persistence. This paper focuses on barnacle (Semibalanus balanoides) recruitment. In rocky intertidal habitats from the Gulf of St. Lawrence coast of Nova Scotia (Canada), ice scour is common during the winter. At the onset of intertidal barnacle recruitment in early May (after sea ice has fully melted), mostly only adult barnacles and bare substrate are visible at high elevations in wave-exposed habitats. We conducted a multiannual study to investigate if small-scale barnacle recruitment could be predicted from the density of pre-existing adult barnacles. In a year that exhibited a wide adult density range (ca. 0–130 individuals dm−2), the relationship between adult density and recruit density (scaled to the available area for recruitment, which excluded adult barnacles) was unimodal. In years that exhibited a lower adult density range (ca. 0–40/50 individuals dm−2), the relationship between adult and recruit density was positive and resembled the lower half of the unimodal relationship. Overall, adult barnacle density was able to explain 26–40% of the observed variation in recruit density. The unimodal adult–recruit relationship is consistent with previously documented intraspecific interactions. Between low and intermediate adult densities, the positive nature of the relationship relates to the previously documented fact that settlement-seeking larvae are chemically and visually attracted to adults, which might be important for local population persistence. Between intermediate and high adult densities, where population persistence may be less compromised and the abundant adults may limit recruit growth and survival, the negative nature of the relationship suggests that adult barnacles at increasingly high densities stimulate larvae to settle elsewhere. The unimodal pattern may be especially common on shores with moderate rates of larval supply to the shore, because high rates of larval supply may swamp the coast with settlers, decoupling recruit density from local adult abundance.

A 12-year record of intertidal barnacle recruitment in Atlantic Canada (2005-2016): relationships with sea surface temperature and phytoplankton abundance

Scrosati RA, Ellrich JA. A 12-year record of intertidal barnacle recruitment in Atlantic Canada (2005-2016): relationships with sea surface temperature and phytoplankton abundance. PeerJ [Internet]. 2016 ;4:e2623. Available from: https://peerj.com/articles/2623/
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

On the Gulf of St. Lawrence coast of Nova Scotia (Canada), recruitment of the barnacle Semibalanus balanoides occurs in May and June. Every year in June between 2005 and 2016, we recorded recruit density for this barnacle at the same wave-exposed rocky intertidal location on this coast. During these 12 years, mean recruit density was lowest in 2015 (198 recruits dm−2) and highest in 2007 (969 recruits dm−2). The highest recruit density observed in a single quadrat was 1,457 recruits dm−2 (in 2011) and the lowest was 34 recruits dm−2 (in 2015). Most barnacle recruits appear during May, which suggests that most pelagic larvae (which develop over 5–6 weeks before benthic settlement) are in the water column in April. An AICc-based model selection approach identified sea surface temperature (SST) in April and the abundance of phytoplankton (food for barnacle larvae, measured as chlorophyll-a concentration –Chl-a–) in April as good explanatory variables. Together, April SST and April Chl-a explained 51% of the observed interannual variation in recruit density, with an overall positive influence. April SST was positively related to March–April air temperature (AT). April Chl-a was negatively related to the April ratio between the number of days with onshore winds (which blow from phytoplankton-limited offshore waters) and the number of days with alongshore winds (phytoplankton is more abundant on coastal waters). Therefore, this study suggests that climatic processes affecting April SST and April Chl-a indirectly influence intertidal barnacle recruitment by influencing larval performance.

Jellyfish on the menu: mtDNA assay reveals scyphozoan predation in the Irish Sea

Lamb PD, Hunter E, Pinnegar JK, Creer S, Davies RG, Taylor MI. Jellyfish on the menu: mtDNA assay reveals scyphozoan predation in the Irish Sea. Royal Society Open Science [Internet]. 2017 ;4(11):171421. Available from: http://rsos.royalsocietypublishing.org/content/4/11/171421
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Localized outbreaks of jellyfish, known as blooms, cause a variety of adverse ecological and economic effects. However, fundamental aspects of their ecology remain unknown. Notably, there is scant information on the role jellyfish occupy in food webs: in many ecosystems, few or no predators are known. To identify jellyfish consumers in the Irish Sea, we conducted a molecular gut content assessment of 50 potential predators using cnidarian-specific mtDNA primers and sequencing. We show that jellyfish predation may be more common than previously acknowledged: uncovering many previously unknown jellyfish predators. A substantial proportion of herring and whiting were found to have consumed jellyfish. Rare ingestion was also detected in a variety of other species. Given the phenology of jellyfish in the region, we suggest that the predation was probably targeting juvenile stages of the jellyfish life cycle.

Lack of evidence that governance structures provide real ecological benefits in marine protected areas

Stafford R. Lack of evidence that governance structures provide real ecological benefits in marine protected areas. Ocean & Coastal Management [Internet]. 2018 ;152:57 - 61. Available from: http://www.sciencedirect.com/science/article/pii/S0964569117307433
Freely available?: 
No
Summary available?: 
No
Approximate cost to purchase or rent this item from the publisher: 
US $35.95
Type: Journal Article

The Convention on Biological Diversity (CBD) has set targets for the total area of marine protected areas (MPAs), as well as targets to encourage a participatory approach to governance with equitable sharing of benefits of these areas to multiple stakeholders. These targets have contributed to a considerable volume of research in MPA governance, and in the ecological effectiveness of MPAs. However, examining the literature demonstrates there is very little joined up research to show that any particular governance approach results in improved ecological indices of fish stocks or biodiversity. Indeed, some of the well-cited examples of participatory governance implying improved ecological metrics are either incorrect (as data do not relate to MPAs under participatory governance systems), or do not provide any ecological data other than opinions of fishers to back up the claims. Evidence suggests that participatory governance approaches with equitable sharing of benefits can help the establishment and management of MPAs, and as such, there should be urgent further work assessing the ecological benefits that arise as a result of the establishment of MPAs with participatory and equitable governance approaches.

Evidence of molting and the function of “rock-nosing” behavior in bowhead whales in the eastern Canadian Arctic

Fortune SME, Koski WR, Higdon JW, Trites AW, Baumgartner MF, Ferguson SH. Evidence of molting and the function of “rock-nosing” behavior in bowhead whales in the eastern Canadian Arctic Li S. PLOS ONE [Internet]. 2017 ;12(11):15p. Available from: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0186156
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Bowhead whales (Balaena mysticetus) have a nearly circumpolar distribution, and occasionally occupy warmer shallow coastal areas during summertime that may facilitate molting. However, relatively little is known about the occurrence of molting and associated behaviors in bowhead whales. We opportunistically observed whales in Cumberland Sound, Nunavut, Canada with skin irregularities consistent with molting during August 2014, and collected a skin sample from a biopsied whale that revealed loose epidermis and sloughing. During August 2016, we flew a small unmanned aerial system (sUAS) over whales to take video and still images to: 1) determine unique individuals; 2) estimate the proportion of the body of unique individuals that exhibited sloughing skin; 3) determine the presence or absence of superficial lines representative of rock-rubbing behavior; and 4) measure body lengths to infer age-class. The still images revealed that all individuals (n = 81 whales) were sloughing skin, and that nearly 40% of them had mottled skin over more than two-thirds of their bodies. The video images captured bowhead whales rubbing on large rocks in shallow, coastal areas—likely to facilitate molting. Molting and rock rubbing appears to be pervasive during late summer for whales in the eastern Canadian Arctic.

Characterizing Coastal Ecosystem Service Trade-offs with Future Urban Development in a Tropical City

Richards DR, Friess DA. Characterizing Coastal Ecosystem Service Trade-offs with Future Urban Development in a Tropical City. Environmental Management [Internet]. 2017 ;60(5):961 - 973. Available from: https://link.springer.com/article/10.1007%2Fs00267-017-0924-2
Freely available?: 
No
Summary available?: 
No
Approximate cost to purchase or rent this item from the publisher: 
US $39.95
Type: Journal Article

With rapid urbanization in the coastal zone and increasing habitat losses, it is imperative to understand how urban development affects coastal biodiversity and ecosystem service provision. Furthermore, it is important to understand how habitat fragments can best be incorporated into broader land use planning and coastal management, in order to maximize the environmental benefits they provide. In this study, we characterized the trade-offs between (a) urban development and individual mangrove environmental indicators (habitat quality and ecosystem services), and (b) between different environmental indicators in the tropical nation of Singapore. A range of biological, biophysical, and cultural indicators, including carbon, charcoal production, support for offshore fisheries, recreation, and habitat quality for a threatened species were quantified using field-based, remote sensing, and expert survey methods. The shape of the trade-off Pareto frontiers was analyzed to assess the sensitivity of environmental indicators for development. When traded off individually with urban development, four out of five environmental indicators were insensitive to development, meaning that relatively minor degradation of the indicator occurred while development was below a certain threshold, although indicator loss accelerated once this threshold was reached. Most of the pairwise relationships between the five environmental indicators were synergistic; only carbon storage and charcoal production, and charcoal production and recreational accessibility showed trade-offs. Trade-off analysis and land use optimization using Pareto frontiers could be a useful decision-support tool for understanding how changes in land use and coastal management will impact the ability of ecosystems to provide environmental benefits.

Linking 1D coastal ocean modelling to environmental management: an ensemble approach

Mussap G, Zavatarelli M, Pinardi N. Linking 1D coastal ocean modelling to environmental management: an ensemble approach. Ocean Dynamics [Internet]. 2017 ;67(12):1627 - 1644. Available from: https://link.springer.com/article/10.1007%2Fs10236-017-1106-8
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

The use of a one-dimensional interdisciplinary numerical model of the coastal ocean as a tool contributing to the formulation of ecosystem-based management (EBM) is explored. The focus is on the definition of an experimental design based on ensemble simulations, integrating variability linked to scenarios (characterised by changes in the system forcing) and to the concurrent variation of selected, and poorly constrained, model parameters. The modelling system used was previously specifically designed for the use in “data-rich” areas, so that horizontal dynamics can be resolved by a diagnostic approach and external inputs can be parameterised by nudging schemes properly calibrated. Ensembles determined by changes in the simulated environmental (physical and biogeochemical) dynamics, under joint forcing and parameterisation variations, highlight the uncertainties associated to the application of specific scenarios that are relevant to EBM, providing an assessment of the reliability of the predicted changes. The work has been carried out by implementing the coupled modelling system BFM-POM1D in an area of Gulf of Trieste (northern Adriatic Sea), considered homogeneous from the point of view of hydrological properties, and forcing it by changing climatic (warming) and anthropogenic (reduction of the land-based nutrient input) pressure. Model parameters affected by considerable uncertainties (due to the lack of relevant observations) were varied jointly with the scenarios of change. The resulting large set of ensemble simulations provided a general estimation of the model uncertainties related to the joint variation of pressures and model parameters. The information of the model result variability aimed at conveying efficiently and comprehensibly the information on the uncertainties/reliability of the model results to non-technical EBM planners and stakeholders, in order to have the model-based information effectively contributing to EBM.

Competing tradeoffs between increasing marine mammal predation and fisheries harvest of Chinook salmon

Chasco BE, Kaplan IC, Thomas AC, Acevedo-Gutiérrez A, Noren DP, Ford MJ, M. Hanson B, Scordino JJ, Jeffries SJ, Marshall KN, et al. Competing tradeoffs between increasing marine mammal predation and fisheries harvest of Chinook salmon. Scientific Reports [Internet]. 2017 ;7(1). Available from: https://www.nature.com/articles/s41598-017-14984-8
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Many marine mammal predators, particularly pinnipeds, have increased in abundance in recent decades, generating new challenges for balancing human uses with recovery goals via ecosystem-based management. We used a spatio-temporal bioenergetics model of the Northeast Pacific Ocean to quantify how predation by three species of pinnipeds and killer whales (Orcinus orca) on Chinook salmon (Oncorhynchus tshawytscha) has changed since the 1970s along the west coast of North America, and compare these estimates to salmon fisheries. We find that from 1975 to 2015, biomass of Chinook salmon consumed by pinnipeds and killer whales increased from 6,100 to 15,200 metric tons (from 5 to 31.5 million individual salmon). Though there is variation across the regions in our model, overall, killer whales consume the largest biomass of Chinook salmon, but harbor seals (Phoca vitulina) consume the largest number of individuals. The decrease in adult Chinook salmon harvest from 1975–2015 was 16,400 to 9,600 metric tons. Thus, Chinook salmon removals (harvest + consumption) increased in the past 40 years despite catch reductions by fisheries, due to consumption by recovering pinnipeds and endangered killer whales. Long-term management strategies for Chinook salmon will need to consider potential conflicts between rebounding predators or endangered predators and prey.

Parallel epigenetic modifications induced by hatchery rearing in a Pacific salmon

Le Luyer J, Laporte M, Beacham TD, Kaukinen KH, Withler RE, Leong JS, Rondeau EB, Koop BF, Bernatchez L. Parallel epigenetic modifications induced by hatchery rearing in a Pacific salmon. Proceedings of the National Academy of Sciences [Internet]. 2017 :201711229. Available from: http://www.pnas.org/content/early/2017/11/20/1711229114.abstract.html?etoc
Freely available?: 
No
Summary available?: 
No
Approximate cost to purchase or rent this item from the publisher: 
US $10.00
Type: Journal Article

Wild stocks of Pacific salmonids have experienced sharp declines in abundance over the past century. Consequently, billions of fish are released each year for enhancing abundance and sustaining fisheries. However, the beneficial role of this widely used management practice is highly debated since fitness decrease of hatchery-origin fish in the wild has been documented. Artificial selection in hatcheries has often been invoked as the most likely explanation for reduced fitness, and most studies to date have focused on finding signatures of hatchery-induced selection at the DNA level. We tested an alternative hypothesis, that captive rearing induces epigenetic reprogramming, by comparing genome-wide patterns of methylation and variation at the DNA level in hatchery-reared coho salmon (Oncorhynchus kisutch) with those of their wild counterparts in two geographically distant rivers. We found a highly significant proportion of epigenetic variation explained by the rearing environment that was as high as the one explained by the river of origin. The differentially methylated regions show enrichment for biological functions that may affect the capacity of hatchery-born smolts to migrate successfully in the ocean. Shared epigenetic variation between hatchery-reared salmon provides evidence for parallel epigenetic modifications induced by hatchery rearing in the absence of genetic differentiation between hatchery and natural-origin fish for each river. This study highlights epigenetic modifications induced by captive rearing as a potential explanatory mechanism for reduced fitness in hatchery-reared salmon.

Lost, but Found with Nile Red: A Novel Method for Detecting and Quantifying Small Microplastics (1 mm to 20 μm) in Environmental Samples

Erni-Cassola G, Gibson MI, Thompson RC, Christie-Oleza JA. Lost, but Found with Nile Red: A Novel Method for Detecting and Quantifying Small Microplastics (1 mm to 20 μm) in Environmental Samples. Environmental Science & Technology [Internet]. 2017 . Available from: http://pubs.acs.org/doi/10.1021/acs.est.7b04512
Freely available?: 
No
Summary available?: 
No
Approximate cost to purchase or rent this item from the publisher: 
US $40.00
Type: Journal Article

Marine plastic debris is a global environmental problem. Surveys have shown that <5 mm plastic particles, known as microplastics, are significantly more abundant in surface seawater and on shorelines than larger plastic particles are. Nevertheless, quantification of microplastics in the environment is hampered by a lack of adequate high-throughput methods for distinguishing and quantifying smaller size fractions (<1 mm), and this has probably resulted in an underestimation of actual microplastic concentrations. Here we present a protocol that allows high-throughput detection and automated quantification of small microplastic particles (20–1000 μm) using the dye Nile red, fluorescence microscopy, and image analysis software. This protocol has proven to be highly effective in the quantification of small polyethylene, polypropylene, polystyrene, and nylon-6 particles, which frequently occur in the water column. Our preliminary results from sea surface tows show a power-law increase in small microplastics (i.e., <1 mm) with a decreasing particle size. Hence, our data help to resolve speculation about the “apparent” loss of this fraction from surface waters. We consider that this method presents a step change in the ability to detect small microplastics by substituting the subjectivity of human visual sorting with a sensitive and semiautomated procedure.

Cascading predator effects in a Fijian coral reef ecosystem

Rasher DB, Hoey AS, Hay ME. Cascading predator effects in a Fijian coral reef ecosystem. Scientific Reports [Internet]. 2017 ;7(1). Available from: https://www.nature.com/articles/s41598-017-15679-w
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Coral reefs are among Earth’s best-studied ecosystems, yet the degree to which large predators influence the ecology of coral reefs remains an open and contentious question. Recent studies indicate the consumptive effects of large reef predators are too diffuse to elicit trophic cascades. Here, we provide evidence that such predators can produce non-consumptive (fear) effects that flow through herbivores to shape the distribution of seaweed on a coral reef. This trophic cascade emerged because reef topography, tidal oscillations, and shark hunting behaviour interact to create predictable “hot spots” of fear on the reef where herbivores withhold feeding and seaweeds gain a spatial refuge. Thus, in risky habitats, sharks can exert strong ecological impacts even though they are trophic generalists that rarely feed. These findings contextualize the debate over whether predators influence coral reef structure and function and move us to ask not if, but under what specific conditions, they generate trophic cascades.

The Support of MPA (Marine Protected Area) in Coral Triangle Area: Evidence from Kei Islands, Indonesia

Hamid SK, Teniwut WA, Teniwut RMK, Rahantoknam MA, Hasyim CL, Hungan M. The Support of MPA (Marine Protected Area) in Coral Triangle Area: Evidence from Kei Islands, Indonesia. IOP Conference Series: Earth and Environmental Science [Internet]. 2017 ;89:012025. Available from: http://iopscience.iop.org/article/10.1088/1755-1315/89/1/012025/meta
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Kei Islands located inside the coral triangle. Therefore, the biodiversity level on the sea in this area is considered high. United nation has proposed for water that included in the coral triangle has to apply marine protected area (MPA) to preserve the area. The main problem is most of the community especially in Kei Islands have depended on the sea as their sources of the economy even fisheries commodity like fish play a large part on the inflation rate and other prosperity indicators likes school and housing. Also, Kei Islands practice on form local wisdom for owning areal of the sea which calls "petuanan laut" by certain of villages or group of villages in one area. This study aimed to map the cluster of catching fisheries area based on the quantity of fish supply on a local market in Kei Islands and measure each cluster on their support and perspective on Marine Protected Area (MPA). We conducted a focus group discussion and collecting additional data by questionnaires with descriptive and quantitative analysis with logistic regression. The implication of this study can provide a clear view of coastal communities view on MPA program also to identify an area that has marine resources, human resources, and equipment to provide government an empirical view on catching fisheries in Kei Islands to issued better policy to develop fishing industry in Kei Islands.

Enhanced larval supply and recruitment can replenish reef corals on degraded reefs

Cruz DW dela, Harrison PL. Enhanced larval supply and recruitment can replenish reef corals on degraded reefs. Scientific Reports [Internet]. 2017 ;7(1). Available from: https://www.nature.com/articles/s41598-017-14546-y
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Reef-building corals have essential roles in reef ecosystems but are highly susceptible to disturbances. Increasing anthropogenic disturbances are eroding coral community resilience, leading to declining reef ecosystem function and status globally. Successful reproduction and recruitment are essential for restoring coral populations but recruitment-limitation can constrain recovery. We supplied ~400,000 Acropora tenuis larvae in fine-mesh enclosures on each of four larval-enhancement plots, comprising natural reef substrata and ten settlement tiles, on degraded reef areas in the northwestern Philippines. Initial mean total settlement on tiles in larval-enhancement plots was high (255.3 ± 68.6), whereas no larvae settled in natural control plots. Recruit survivorship began stabilising after five months, with juveniles becoming visible by eye at nine months. After three years a mean of 2.3 m−2 colonies survived within each larval-enhancement plot. Most colonies grew rapidly (16.1 ± 0.7 cm mean diameter) and spawned successfully at three years, thereby quickly re-establishing a breeding population. In contrast, natural recruitment failed to produce any new visible Atenuis colonies. These results demonstrate that mass larval settlement can rapidly enhance recruitment and coral recovery on degraded reef areas, and provides an important option for active reef restoration where larval supply and recruitment success are limiting.

Rethinking use and trade of pelagic sharks from Brazil

Barreto RR, Bornatowski H, Motta FS, Santander-Neto J, Vianna GMS, Lessa R. Rethinking use and trade of pelagic sharks from Brazil. Marine Policy [Internet]. 2017 ;85:114 - 122. Available from: http://www.sciencedirect.com/science/article/pii/S0308597X17300933
Freely available?: 
No
Summary available?: 
No
Approximate cost to purchase or rent this item from the publisher: 
US $35.95
Type: Journal Article

Brazil currently ranks as the 11th producer and 1st importer of shark meat around the world. Data available from the FAO software FishStatJ along with data from regional sources, such as governmental bulletins, scientific papers, gray literature and internet were revisited to identify the main issues surrounding pelagic shark fisheries, trade and consumption in the largest country in South America. Among the main findings, it was noted that Brazil has not properly collected fishery statistics since 2007, that many species of threatened sharks are freely landed and traded even though it is prohibited by local legislation and/or international recommendations (regional fisheries management organizations). The blue shark (Prionace glauca) is the most frequently recorded shark in the official bulletins and is currently a locally targeted species. Additionally, the significant imports of this species from 23 other countries that also provide fins for Asia has drawn attention in recent decades. Regarding consumption, shark is considered to be low-value seafood compared to more common fish, such as groupers and snappers, and most Brazilians actually do not know that they are eating sharks. At present, the proportion of threatened elasmobranchs (in which sharks are included) in Brazil (33%, of 145 species) exceeds the global rate identified for the group (25%), and, until the present moment, no measure related to the management of species has been implemented. As advice, Brazil urgently needs to restructure its fishery information collection systems, management strategies and to tighten sanitary and labeling regulations for the marketing of fish.

Evaluating anthropogenic threats to endangered killer whales to inform effective recovery plans

Lacy RC, Williams R, Ashe E, III KCBalcomb, Brent LJN, Clark CW, Croft DP, Giles DA, MacDuffee M, Paquet PC. Evaluating anthropogenic threats to endangered killer whales to inform effective recovery plans. Scientific Reports [Internet]. 2017 ;7(1). Available from: https://www.nature.com/articles/s41598-017-14471-0
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Understanding cumulative effects of multiple threats is key to guiding effective management to conserve endangered species. The critically endangered, Southern Resident killer whale population of the northeastern Pacific Ocean provides a data-rich case to explore anthropogenic threats on population viability. Primary threats include: limitation of preferred prey, Chinook salmon; anthropogenic noise and disturbance, which reduce foraging efficiency; and high levels of stored contaminants, including PCBs. We constructed a population viability analysis to explore possible demographic trajectories and the relative importance of anthropogenic stressors. The population is fragile, with no growth projected under current conditions, and decline expected if new or increased threats are imposed. Improvements in fecundity and calf survival are needed to reach a conservation objective of 2.3% annual population growth. Prey limitation is the most important factor affecting population growth. However, to meet recovery targets through prey management alone, Chinook abundance would have to be sustained near the highest levels since the 1970s. The most optimistic mitigation of noise and contaminants would make the difference between a declining and increasing population, but would be insufficient to reach recovery targets. Reducing acoustic disturbance by 50% combined with increasing Chinook by 15% would allow the population to reach 2.3% growth.

Elasmobranch fisheries in the Arabian Seas Region: Characteristics, trade and management

Jabado RW, L Y Spaet J. Elasmobranch fisheries in the Arabian Seas Region: Characteristics, trade and management. Fish and Fisheries [Internet]. 2017 ;18(6):1096 - 1118. Available from: http://onlinelibrary.wiley.com/doi/10.1111/faf.12227/abstract
Freely available?: 
No
Summary available?: 
No
Approximate cost to purchase or rent this item from the publisher: 
US $38.00
Type: Journal Article

The Arabian Seas Region plays an important role in the global landings and trade of sharks and rays. The United Arab Emirates (UAE) and Yemen, two countries with stark socio-economic differences, serve as major regional trade hubs for shark and ray products and four countries (Oman, Pakistan, UAE and Yemen) supply nearly 11% of dried fin exports to Hong Kong. Yet, little information is available on the characteristics of this trade and the fisheries contributing to it. Here, we review the fisheries characteristics, trade, utilization and distribution chain of sharks and rays in 15 countries of the Arabian Seas Region based on published and grey literature, landing surveys, field observations and interviews with fishermen and traders. Although regional shark fisheries remain mostly artisanal, reported shark and ray landings represent 28% of the regional total fish production, reaching 56,074 mt in 2012 (7.3% of total world catches), with Iran, Oman, Pakistan and Yemen ranking as the primary catchers. Utilization and distribution patterns are complex, vary between landing sites and countries, and remain unmonitored. Based on widespread over-exploitation of most teleost fisheries, current exploitation levels for most sharks and rays are potentially unsustainable. The situation is exacerbated by limited research and political will to support policy development, the incomplete nature of fisheries data, as well as insufficient regulations and enforcement. A better understanding of shark and ray fisheries will be key for regulating trade, promoting conservation and developing management initiatives to secure food security, livelihoods and biodiversity conservation in the region.

Investigating the impacts of treated effluent discharge on coastal water health (Visakhapatnam, SW coast of Bay of Bengal, India)

Shaik AUr Rahman, Biswas H, N. Babu S, Reddy NPC, Ansari ZA. Investigating the impacts of treated effluent discharge on coastal water health (Visakhapatnam, SW coast of Bay of Bengal, India). Environmental Monitoring and Assessment [Internet]. 2017 ;189(12). Available from: https://link.springer.com/article/10.1007/s10661-017-6344-1
Freely available?: 
No
Summary available?: 
No
Approximate cost to purchase or rent this item from the publisher: 
US $39.95
Type: Journal Article

The present study investigated the impacts of treated effluent discharge on physicochemical and biological properties of coastal waters from three pharmaceuticals situated along the coast of Visakhapatnam (SW Bay of Bengal). Seawater samples were collected (during the months of December 2013, March 2014 and April 2014) from different sampling locations (Chippada (CHP), Tikkavanipalem (TKP) and Nakkapalli (NKP)) at 0- and 30-m depths within 2-km radius (0.5 km = inner, 1 km = middle and 2 km = outer sampling circles) from the marine outfall points. Physicochemical and biological parameters, which differed significantly within the stations, were likely to be influenced by strong seasonality rather than local discharge. Dissolved oxygen variability was tightly coupled with both physical and biological processes. Phytoplankton cell density and total chlorophyll (TChla) concentrations were significantly correlated with dissolved inorganic nutrient concentrations. CHP (December) represented a diatom bloom condition where the highest concentrations of diatom cells, total chlorophyll (TChla), dissolved oxygen coupled with lower zooplankton abundance and low nutrient levels were noticed. The centric diatom, Chaetoceros sp. (> 50%) dominated the phytoplankton community. TKP (March) represented a post-diatom bloom phase with the dominance of Pseudo-nitzschia seriata; zooplankton abundance and nutrient concentrations were minimum. Conversely, NKP (April) represented a warm well-stratified heterotrophic period with maximum zooplankton and minimum phytoplankton density. Dinoflagellate abundance increased at this station. Relatively higher water temperature, salinity, inorganic nutrients coupled with very low concentrations of dissolved oxygen, TChla and pH were observed at this station. Copepods dominated the zooplankton communities in all stations and showed their highest abundance in the innermost sampling circles. Treated effluent discharge did not seem to have any significant impact at these discharge points.

The incidence of bent dorsal fins in free-ranging cetaceans

Alves F, Towers JR, Baird RW, Bearzi G, Bonizzoni S, Ferreira R, Halicka Z, Alessandrini A, Kopelman AH, Yzoard C, et al. The incidence of bent dorsal fins in free-ranging cetaceans. Journal of Anatomy [Internet]. 2017 . Available from: http://onlinelibrary.wiley.com/doi/10.1111/joa.12729/full
Freely available?: 
No
Summary available?: 
No
Approximate cost to purchase or rent this item from the publisher: 
US $38.00
Type: Journal Article

Laterally bent dorsal fins are rarely observed in free-ranging populations of cetaceans, contrary to captivity, where most killer whale Orcinus orca adult males have laterally collapsed fins. This topic has been poorly explored, and data/information on its occurrence and possible causes are limited. The present study: (i) undertakes a review of the available information on bent dorsal fins in free-ranging cetaceans, and updates it with new records, (ii) reports on the proportion of bent fins in different study populations, and (iii) discusses possible causes. An empirical approach based on bibliographic research and compilation of 52 new records collected worldwide resulted in a total of 17 species of cetaceans displaying bent dorsal fins. The species with the highest number of records (64%) and from most locations was O. orca. On average, individuals with bent dorsal fins represent < 1% of their populations, with the exception of false killer whales Pseudorca crassidens and O. orca. While line injuries associated with fisheries interactions may be the main cause for P. crassidens, and the vulnerability to health issues caused by the evolutionary enlargement of the fin may be the cause for O. orca adult males, factors contributing to this abnormality for other species are still unclear. The occurrence of bent dorsals could be influenced by a set of variables rather than by a single factor but, irrespective of the cause, it is suggested that it does not directly affect the animals' survivorship. While still rare in nature, this incident is more common (at least 101 known cases) and widespread (geographically and in species diversity) than hypothesized, and is not confined only to animals in captive environments. Investigation into the occurrence of bent fins may be an interesting avenue of research.

Assessing the social and economic impact of small scale fisheries management measures in a marine protected area with limited data

Goti-Aralucea L. Assessing the social and economic impact of small scale fisheries management measures in a marine protected area with limited data. Marine Policy [Internet]. In Press . Available from: https://www.sciencedirect.com/science/article/pii/S0308597X16308430
Freely available?: 
No
Summary available?: 
No
Approximate cost to purchase or rent this item from the publisher: 
US $35.95
Type: Journal Article

The European Union requires that major legislative actions undergo an impact assessment (IA), but this methodology is often not adapted to policy measures in complex situations, as the coexistence of marine protected areas and small scale fisheries.

The appropriateness of the IA methodology currently in use is tested on the example of a small scale fishery in a protected area in the German coast in the Baltic Sea (Fehmarn island). The impact of the fisheries management measures is first assessed using the available data and the results are then checked with the local fishermen and a producer organization representative using a focus group. Given the discrepancies identified in the focus group, additional methodologies are explored.

By performing a literature review and a workshop with scientists, fishermen representatives, environmental organizations and managers, inputs from political science (the “wicked problem” approach) and philosophy of science (the NUSAP matrix) are applied to cope with the context of high uncertainty driven by poor ecological, economic and social data.

This case study brings the opportunity to identify challenges as the assessment of biodiversity and potentially conflictive differences in national policy objectives under different EU policies (including the Common Fisheries Policy), in a way that goes beyond the contribution of other commonly used management tools as impact assessment and spatial planning. The usefulness of the approach resides both in a better identification of impacts on small scale fisheries and the unveiling of hidden governance conflicts that prevent the fulfilment of the objectives of policy measures.

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