2017-05-03

MRI and MRS on preserved samples as a tool in fish ecology

Bock C, Wermter FC, Mintenbeck K. MRI and MRS on preserved samples as a tool in fish ecology. Magnetic Resonance Imaging [Internet]. 2017 ;38:39 - 46. Available from: http://www.sciencedirect.com/science/article/pii/S0730725X16302648
Freely available?: 
No
Summary available?: 
No
Approximate cost to purchase or rent this item from the publisher: 
US $35.95
Type: Journal Article

Magnetic Resonance Imaging (MRI) and Magnetic Resonance Spectroscopy (MRS) gain increasing attention and importance as a tool in marine ecology. So far, studies were largely limited to morphological studies, e.g. for the creation of digital libraries. Here, the utility of MRI and MRS for ecologists is tested and exemplified using formalin preserved samples of the Antarctic silverfish, Pleuragramma antarctica. As this species lacks a swim bladder, buoyancy is attained by the deposition of large amounts of lipids that are mainly stored in subcutaneous and intermuscular lipid sacs. In this study MRI and MRS are not only used to study internal morphology, but additionally to investigate functional morphology and to measure parameters of high ecological interest. The data are compared with literature data obtained by means of traditional ecological methods.

The results from this study show that MR scans are not only an alternative to histological sections (as shown before), but even allow the visualization of particular features in delicate soft tissues, such as Pleuragramma's lipid sacs. 3D rendering techniques proved to be a useful tool to study organ volumes and lipid content, which usually requires laborious chemical lipid extraction and analysis. Moreover, the application of MRS even allows for an analysis of lipids and fatty acids within lipid sacs, which wouldn't be possible using destructive methods. MRI and MRS, in particular when used in combination, have the capacity to provide useful data on parameters of high ecological relevance and thus have proven to be a highly valuable addition, if not alternative, to the classical methods.

Are anthropogenic factors affecting nesting habitat of sea turtles? The case of Kanzul beach, Riviera Maya-Tulum (Mexico)

de la Esperanza AOliver, Martínez AArenas, Tuz MTzeek, Pérez-Collazos E. Are anthropogenic factors affecting nesting habitat of sea turtles? The case of Kanzul beach, Riviera Maya-Tulum (Mexico). Journal of Coastal Conservation [Internet]. 2017 ;21(1):85 - 93. Available from: https://link.springer.com/article/10.1007/s11852-016-0473-5
Freely available?: 
No
Summary available?: 
No
Approximate cost to purchase or rent this item from the publisher: 
US $39.95
Type: Journal Article

Marine coast modification and human pressure affects many species, including sea turtles. In order to study nine anthropogenic impacts that might affect nesting selection of females, incubation and hatching survival of loggerhead (Caretta caretta) and green turtle (Chelonia mydas), building structures were identified along a 5.2 km beach in Kanzul (Mexico). A high number of hotels and houses (88; 818 rooms), with an average density of 16.6 buildings per kilometer were found. These buildings form a barrier which prevents reaching the beach from inland, resulting in habitat fragmentation. Main pressures were detected during nesting selection (14.19% of turtle nesting attempts interrupted), and low impact were found during incubation (0.77%) and hatching (4.7%). There were three impacts defined as high: beach furniture that blocks out the movement of hatchlings or females, direct pressure by tourists, and artificial beachfront lighting that can potentially mislead hatchlings or females. High impacted areas showed lowest values in nesting selection and hatching success. Based on our results, we suggest management strategies to need to be implemented to reduce human pressure and to avoid nesting habitat loss of loggerhead and green turtle in Kanzul, Mexico.

The incorporation of traditional knowledge into Alaska federal fisheries management

Raymond-Yakoubian J, Raymond-Yakoubian B, Moncrieff C. The incorporation of traditional knowledge into Alaska federal fisheries management. Marine Policy [Internet]. 2017 ;78:132 - 142. Available from: http://www.sciencedirect.com/science/article/pii/S0308597X16307825
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Fisheries policy and management processes for federal waters off western Alaska currently lack consistent and considered integration of traditional knowledge (TK), TK holders, social science of TK, and subsistence information. The incorporation of these into fisheries work can lead to more informed, equitable and effective policy and management practices. This paper includes information and recommendations derived from previous work by the authors as well as from two community workshops with indigenous TK holders and fisheries experts. Discussions of TK and related concepts, TK research in the Bering Strait and Yukon River regions, and Alaska federal fisheries management-related institutions and processes as pertains to TK are presented. Substantive recommendations are provided for improving processes, increasing tribal representation, capacity building, effective communication, outreach and relationship-building, the incorporation of indigenous concerns and values, and regarding the development of a Fisheries Ecosystem Plan for the Bering Sea.

A framework for predicting impacts on ecosystem services from (sub)organismal responses to chemicals

Forbes VE, Salice CJ, Birnir B, Bruins RJF, Calow P, Ducrot V, Galic N, Garber K, Harvey BC, Jager H, et al. A framework for predicting impacts on ecosystem services from (sub)organismal responses to chemicals. Environmental Toxicology and Chemistry [Internet]. 2017 ;36(4):845 - 859. Available from: http://onlinelibrary.wiley.com/doi/10.1002/etc.3720/full
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Protection of ecosystem services is increasingly emphasized as a risk-assessment goal, but there are wide gaps between current ecological risk-assessment endpoints and potential effects on services provided by ecosystems. The authors present a framework that links common ecotoxicological endpoints to chemical impacts on populations and communities and the ecosystem services that they provide. This framework builds on considerable advances in mechanistic effects models designed to span multiple levels of biological organization and account for various types of biological interactions and feedbacks. For illustration, the authors introduce 2 case studies that employ well-developed and validated mechanistic effects models: the inSTREAM individual-based model for fish populations and the AQUATOX ecosystem model. They also show how dynamic energy budget theory can provide a common currency for interpreting organism-level toxicity. They suggest that a framework based on mechanistic models that predict impacts on ecosystem services resulting from chemical exposure, combined with economic valuation, can provide a useful approach for informing environmental management. The authors highlight the potential benefits of using this framework as well as the challenges that will need to be addressed in future work.

Size-structural shifts reveal intensity of exploitation in coral reef fisheries

Zgliczynski BJ, Sandin SA. Size-structural shifts reveal intensity of exploitation in coral reef fisheries. Ecological Indicators [Internet]. 2017 ;73:411 - 421. Available from: http://www.sciencedirect.com/science/article/pii/S1470160X16305763
Freely available?: 
No
Summary available?: 
No
Approximate cost to purchase or rent this item from the publisher: 
US $35.95
Type: Journal Article

Fisheries exploitation represents a considerable threat to coral reef fish resources because even modest levels of extraction can alter ecological dynamics via shifts of stock size, species composition, and size-structure of the fish assemblage. Although species occupying higher trophic groups are known to suffer the majority of exploitative effects, changes in composition among lower trophic groups may be major, though are not frequently explored. Using size-based biomass spectrum analysis, we investigate the effects of fishing on the size-structure of coral reef fish assemblages spanning four geopolitical regions and determine if patterns of exploitation vary across trophic groups. Our analyses reveal striking evidence for the variety of effects fisheries exploitation can have on coral reef fish assemblages. When examining biomass spectra across the entire fish assemblage we found consistent evidence of size-specific exploitation, in which large-bodied individuals experience disproportionate reductions. The pattern was paralleled by and likely driven by, strongly size-specific reductions among top predators. In contrast, evidence of exploitation patterns was variable among lower trophic groups, in many cases including evidence of reductions across all size classes. The breadth of size classes and trophic groups that showed evidence of exploitation related positively to local human population density and diversity of fishing methods employed. Our findings highlight the complexity of coral reef fisheries and that the effects of exploitation on coral reefs can be realized throughout the entire fish assemblage, across multiple trophic groups and not solely restricted to large-bodied top-predators. Size-specific changes among fishes of lower trophic groups likely lead to altered ecological functioning of heavily exploited coral reefs. Together these findings reinforce the value of taking a multi-trophic group approach to monitoring and managing coral reef fisheries.

Evaluating the combined effects of ballast water management and trade dynamics on transfers of marine organisms by ships

Carney KJ, Minton MS, Holzer KK, A. Miller W, McCann LD, Ruiz GM. Evaluating the combined effects of ballast water management and trade dynamics on transfers of marine organisms by ships. PLOS ONE [Internet]. 2017 ;12(3):e0172468. Available from: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0172468
Freely available?: 
Yes
Summary available?: 
No
Type: Journal Article

Global trade by merchant ships is a leading mechanism for the unintentional transfer of marine organisms, including non-indigenous species, to bays and estuaries worldwide. To reduce the likelihood of new invasions, ships are increasingly being required to manage their ballast water (BW) prior to discharge in coastal waters. In the United States, most overseas arrivals have been required to manage BW discharge since 2004, primarily through ballast water exchange (BWE), which flushes out ballast tanks in the open ocean (>200 miles from shore). Studies have found BWE to generally reduce the abundance of organisms, and the amount of water exchanged has been estimated at 96–100%. Despite its widespread use, the overall effect of this management strategy on net propagule supply through time has not been explored. Here, temporal changes in zooplankton concentrations and the volume of BW discharged in Chesapeake Bay, U.S. were evaluated, comparing pre-management era and post-management era time periods. Chesapeake Bay is a large port system that receives extensive BW discharge, especially from bulk cargo vessels (bulkers) that export coal overseas. For bulkers arriving from overseas, mean zooplankton concentrations of total and coastal indicator taxa in BW did not decline between pre- (1993–2000) and post management (2012–2013) eras, when controlling for season and sampling method. Moreover, bulkers discharged 21 million tonnes (82% of total for Chesapeake Bay) of overseas BW in 2013, representing a 374% increase in volume when compared to 2005. The combination of BW discharge volume and zooplankton concentration data indicates that (a) net propagule supply by bulkers has increased since BWE began in Chesapeake Bay; and (b) changes in vessel behaviour and trade have contributed strongly to this outcome. Specifically, the coal-driven increase in BW discharge volume from 2005–2013, concurrent with the onset of BWE regulations, worked to counteract intended results from BW management. A long-term analysis of bulker arrivals (1994–2013) reveals a 20-year minimum in arrival numbers in 2000, just when the implementation of BWE began. This study underscores the need to consider shifts in trade patterns, in order to advance and evaluate effective management strategies for biological invasions.

Assistance networks in seafood trade – A means to assess benefit distribution in small-scale fisheries

O'Neill EDrury, Crona B. Assistance networks in seafood trade – A means to assess benefit distribution in small-scale fisheries. Marine Policy [Internet]. 2017 ;78:196 - 205. Available from: http://www.sciencedirect.com/science/article/pii/S0308597X16306443
Freely available?: 
No
Summary available?: 
No
Approximate cost to purchase or rent this item from the publisher: 
US $35.95
Type: Journal Article

This article addresses the connections between value chain actors in the tropical-marine small-scale fisheries of Zanzibar, Tanzania, to contribute to a better understanding of the fisher-trader link and how connections in general might feed into livelihood security. A sample of 168 fishers and 130 traders was taken across 8 sites through questionnaires and observations. The small-scale fishery system is mapped using a value chain framework both traditionally and from a less economic point of view where the assistance-exchange networks between fishery actors add another layer of complexity. Auxiliary actors previously disregarded emerge from the latter method thus shedding light on the poorly understood distribution of benefits from seafood trade. Female actors participate quite differently, relative to males in the market system, detached from high-value links such as the tourist industry, and access to predetermined or secured sales deals. Data shows that the fisher-trader link is not as one-sided as previously presented. In fact it has a more symbiotic exchange deeply nested in a broader trading and social system. Expanding the analysis from this link by taking a further step downstream highlights traders’ own sales arrangements and the social pressures they are under in realizing them. A complex picture, inclusive of diversified perspectives, on interactions in the market place is presented, as well as a reflection on the remaining critical question: how to integrate this type of data into decisions about future fisheries governance.

Climate-resilient infrastructure: Getting the policies right

Vallejo L, Mullan M. Climate-resilient infrastructure: Getting the policies right. France: OECD; 2017. Available from: http://www.oecd-ilibrary.org/environment/climate-resilient-infrastructure_02f74d61-en
Freely available?: 
Yes
Summary available?: 
No
Type: Report

Climate change will affect all types of infrastructure, including energy, transport and water. Rising temperatures, increased flood risk and other potential hazards will threaten the reliable and efficient operation of these networks, with potentially large economic and social impacts. Decisions made now about the design, location and operation of infrastructure will determine how resilient they will be to a changing climate.

This paper provides a framework for action aimed at national policymakers in OECD countries to help them ensure new and existing infrastructure is resilient to climate change. It examines national governments’ action in OECD countries, and provides recent insights from professional and industry associations, development banks and other financial institutions on how to make infrastructure more resilient to climate change.

Effects of a hook ring on catch and bycatch in a Mediterranean swordfish longline fishery: small addition with potentially large consequences

Piovano S, Swimmer Y. Effects of a hook ring on catch and bycatch in a Mediterranean swordfish longline fishery: small addition with potentially large consequences. Aquatic Conservation: Marine and Freshwater Ecosystems [Internet]. 2017 ;27(2):372 - 380. Available from: http://onlinelibrary.wiley.com/doi/10.1002/aqc.2689/abstract
Freely available?: 
No
Summary available?: 
No
Approximate cost to purchase or rent this item from the publisher: 
US $38.00
Type: Journal Article
  1. The purpose of this study was to investigate the effects of a circle hook ring on catch rates of target fish species and bycatch rates of sea turtles, elasmobranchs, and non-commercial fish in a shallow-set Italian swordfish longline fishery.

  2. Results were compared from 65 sets from six commercial fishing vessels totalling 50 800 hooks in which ringed and non-ringed 16/0 circle hooks with a 10° offset were alternated along the length of the longline. In total, 464 individuals were caught in the 4 years of experiment, with swordfish (Xiphias gladius) comprising 83% of the total number of animals captured. Catch rates of targeted swordfish were significantly higher on ringed hooks (CPUEringed hooks = 8.465, CPUEnon-ringed hooks = 6.654).

  3. Results indicate that ringed circle hooks captured significantly more small-sized swordfish than non-ringed circle hooks (27.7% vs. 19.5%, respectively).

  4. For species with sufficient sample sizes, the odds ratio (OR) of a capture was in favour of ringed hooks; significantly for swordfish (OR = 1.27 95%CI 1.04–1.57), and not significantly for bluefin tuna (Thunnus thynnus) (OR = 1.50, 95%CI 0.68–3.42) nor for pelagic stingray (Pteroplatytrigon violacea) (OR = 1.13, 95%CI 0.54–2.36). All six loggerhead turtles (Caretta caretta) and three of the four blue sharks (Prionace glauca) were captured on ringed hooks, however, the small sample sizes prevented meaningful statistical analysis.

  5. In summary, results from this study suggest that the addition of a ring to 16/0 circle hooks confers higher catchability for small-sized commercial swordfish, and does not significantly reduce catch rate of bycatch species and protected species in a Mediterranean shallow pelagic longline fishery.

  6. These findings should motivate fisheries managers to consider factors in addition to hook shape when aiming to promote sustainable fishing practices. The presence of a ring has the potential to negate some conservation benefits.

Payments for Ecosystem Services in China: Policy, practice, and progress

Pan X, Xu L, Yang Z, Yu B. Payments for Ecosystem Services in China: Policy, practice, and progress. Journal of Cleaner Production [Internet]. 2017 . Available from: http://www.sciencedirect.com/science/article/pii/S0959652617308545
Freely available?: 
No
Summary available?: 
No
Approximate cost to purchase or rent this item from the publisher: 
US $39.95
Type: Journal Article

The rapid emergence of payments for ecosystem services (PES) schemes in China has been reported widely. However, it seems that the relevant policies and PES practices have not been fully documented. In this study, we provide insights into the overall status of PES schemes in China. We start by introducing the concept of eco-compensation, the equivalent of PES in China, and we describe its initiation and development. We then explore the institutional context upon which PES schemes are based on and we develop a classification system to interpret the different schemes. We employ the concept of PES-like scheme to reconcile divergent views on the scope of PES among researchers and decision makers. Subsequently, we describe the objectives, relevant policies from national to local level, implementation characteristics, funding sources, coverage, payment criteria, and primary effects of the major PES schemes. Broad institutional gaps, scheme overlaps, sole funding source, and the lack of effective tools in monitoring ecological outcomes are identified as major challenges for existing PES schemes. We conclude by proposing to reshape China’s PES frameworks and strengthen the market-based PES schemes, as well as scaling piloting PES schemes up to address pressing ecological issues in broader ecosystems and areas.

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