Living Marine Resources Research Articles

Effects of click rate on bottlenose dolphin auditory brainstem response signal-to-noise ratio

Maximum Length Sequence (MLS) and Iterative Randomized Stimulation and Averaging (I-RSA) methods allow auditory brainstem response (ABR) measurements at high stimulus rates; however, it is not clear if high rates allow ABRs of a given signal-to-noise ratio (SNR) to be measured in less time than conventional averaging at lower rates. In the present study, ABR SNR was examined in six bottlenose dolphins using conventional averaging at rates of 25 and 100 Hz and the MLS/I-RSA approaches from 100 to 1250 Hz. Residual noise in the averaged ABR was estimated using root-mean-square values of the: waveform amplitude following the ABR, waveform amplitude after subtracting two subaverage ABRs, and amplitude variance at a single time point. For all approaches, residual noise decreased with the increasing measurement time. For a fixed recording time, SNR was highest at rates near 500 Hz, but optimal SNRs were only a few dB higher than that for conventional averaging at 100 Hz. Nonetheless, small improvements in SNR could result in significant time savings in reaching criterion SNR. The time savings allowed by the MLS and I-RSA methods will be discussed for both mean and individual data. [Work supported by U.S. Navy Living Marine Resources Program.]

Ocean currents predict fine-scale genetic structure and source-sink dynamics in a marine invertebrate coastal fishery

AbstractEstimates of connectivity are vital for understanding population dynamics and for the design of spatial management areas. However, this is still a major challenge in the marine environment because the relative contributions of factors influencing connectivity amongst subpopulations are difficult to assess. This study combined population genetics with hydrodynamic modelling (Regional Ocean Modeling System, ROMS) to assess spatial and temporal exchange of individuals among subpopulations of the New Zealand scallop, Pecten novaezelandiae, within the Coromandel fishery area open to commercial fishing. Significant genetic differentiation was revealed among subpopulations with variable levels of recruitment. Connectivity, as assessed by ROMS, was a significant explanatory variable of genetic differentiation when accounting for the spatial dependency between locations. Although additional research is needed before source-sink population dynamics can be confidently used in management, these results imply that higher yields could be available from this fishery at lower risk of over-exploitation if the fishing of each subpopulation could be tailored to its contribution to recruitment, perhaps using subpopulation catch limits. This study highlights inter-annual patterns of connectivity, the importance of combining different methods for a better prediction of population dynamics, and how such an approach may contribute to management of living marine resources.

The European Union and the establishment of marine protected areas in Antarctica

This paper examines how the EU can best use its powers to establish marine protected areas (MPAs) in Antarctica. It first discusses the EU’s role in Antarctic governance and legal basis for the EU’s actions, with particular focus on the pending Joined Cases C-625/15 and C-659/16 at the Court of Justice of the European Union. Secondly, the paper analyses the negotiation process of the EU’s MPA proposals in the Southern Ocean within the Commission for the Conservation of Antarctic Marine Living Resources. Thirdly, it provides suggestions regarding the EU’s potential actions that might help achieve proposed Antarctic MPAs.

The CCAMLR Compliance Evaluation Procedure

ABSTRACTThe Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) has developed an institutional Compliance Evaluation Procedure (CCEP). The CCEP aims to enhance CCAMLR’s compliance enforcement capabilities by evaluating fisheries monitoring information, compliance control actions and CCAMLR Contracting Party (CP) cooperation. It appears to improve implementation of CCAMLR Conservation Measures (CMs) in meeting Convention on the Conservation of Antarctic Marine Living Resources (CAMLR Convention) objectives. The legal responsibilities of CPs are considered in relations to the CCEP’s perceived performance in promoting responsible fishing within the CCAMLR Area. Various ideas on the CCEP’s future are offered.

Seasonal to interannual predictability of oceanic net primary production inferred from satellite observations

Seasonal to interannual predictions of ecosystem dynamics have the potential to improve the management of living marine resources. Prediction of oceanic net primary production (NPP), the foundation of marine food webs and the biological carbon pump, is particularly promising, with recent analysis suggesting that ecosystem feedback processes may lead to higher predictability of NPP at interannual scales than for physical variables like sea surface temperature (SST). Here, we assessed the potential predictability of oceanic NPP and SST across seasonal to interannual lead times using reduced dimension, linear dynamical spatio-temporal models (rDSTM). This approach combines empirical orthogonal function (EOF) analysis with vector autoregressive (VAR) modeling to simplify the analysis of spatio-temporal data. The rDSTMs were fitted to monthly NPP and SST anomalies derived from 20 years of remote sensing data (1997–2017), considering two alternative algorithms commonly used to estimate NPP (VGPM and Eppley-VGPM) and optimally analyzed SST fields (AVHRR OISST). The local decay of anomalies provided high predictability up to three months, and subsequent interactions with remote forcing significantly extended predictability beyond the initial anomaly decay. Indeed, interactions among spatial modes associated with the propagation of major climate modes, particularly the El Niño-Southern Oscillation (ENSO), extended the predictability horizon above one year in some regions. Patterns of enhanced NPP predictability matched the location of oligotrophic gyres and transition regions between ocean biomes, where fluctuations in biome boundaries generate large biogeochemical perturbations that leave lasting imprints on NPP. In these areas, the predictability horizon for NPP was longer than for SST, although SST was more predictable over large areas of the equatorial and northeast Pacific. Our results support the potential for extending seasonal to interannual physical climate predictions to predict ocean productivity.

Simulating the ocean’s chlorophyll dynamic range from coastal upwelling to oligotrophy

The measured concentration of chlorophyll a in the surface ocean spans four orders of magnitude, from ∼0.01 mg m−3 in the oligotrophic gyres to >10 mg m−3 in coastal zones. Productive regions encompass only a small fraction of the global ocean area yet they contribute disproportionately to marine resources and biogeochemical processes, such as fish catch and coastal hypoxia. These regions and/or the full observed range of chlorophyll concentration, however, are often poorlyrepresented in global earth system models (ESMs) used to project climate change impacts on marine ecosystems.Furthermore, recent high resolution (∼10 km) global earth system simulations suggest that this shortfall is not solely due to coarse resolution (∼100 km) of most global ESMs. By integrating a global biogeochemical model that includes two phytoplankton size classes (typical of many ESMs) into a regional simulation of the California Current System (CCS) we test the hypothesis that a combination of higher spatial resolution and enhanced resolution of phytoplankton size classes and grazer linkages may enable global ESMs to better capture the full range of observed chlorophyll. The CCS is notable for encompassing both oligotrophic (<0.1 mg m−3) and productive (>10 mg m−3) endpoints of the global chlorophyll distribution.As was the case for global high-resolution simulations, the regional high-resolution implementation with two size classes fails to capture the productive endpoint. The addition of a third phytoplankton size class representing a chain-forming coastal diatom enables such models to capture the full range of chlorophyll concentration along a nutrient supply gradient, from highly productive coastal upwelling systems to oligotrophic gyres. Weaker ‘top-down’ control on coastal diatoms results in stronger trophic decoupling and increased phytoplankton biomass, following the introduction of new nutrients to the photic zone. The enhanced representation of near-shore chlorophyll maxima allows the model to better capture coastal hypoxia along the continental shelf of the North American west coast and may improve the representation of living marine resources.

Estimating recruitment variability and productivity in Antarctic krill

Three alternative forms of the spawner-recruit relationship – the Beverton-Holt and two expressions of the Ricker function - and a fourth form representing annual recruitment deviations without an explicit relationship to spawning biomass, were applied in an integrated assessment model for Antarctic krill. Model data were from the international krill fishery and U.S. AMLR surveys in the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) Subarea 48.1, the area around the Antarctic peninsula where the majority of recent fishing for krill has taken place. Sensitivity tests using pre-specified values for the standard deviation of the logarithm of annual recruitment residuals (σR) and productivity (steepness, h) for the relationship between spawning biomass and subsequent recruitment indicated that neither the Beverton-Holt nor Ricker functions were superior to configurations of the model that did not assume a spawner-recruit relationship. As the predictive power of the spawner-recruit functions was reduced by increasing the value of σR the fit to the data improved. All the functions fitted the data best when σR was large enough so that random recruitment with respect to spawning biomass was produced. The alternative functions produced the same time series of recruitment and spawning biomass estimates when they were determined by the data rather than forced towards an assumed relationship. Although the Beverton-Holt and Ricker models were poor predictors of the data, cross-correlations of the recruitment predictions with the spawning biomass predictions from the best models indicated that recruitment was statistically correlated with spawning biomasses in the previous two to four years. The highest correlation (0.58) was with spawning biomass three years previously. Correlations in the reverse direction, with spawning biomass following recruitment were insignificant. These results suggest that recruitment variability does not influence subsequent spawning biomass in krill. They leave open the possibility that krill spawning biomass could influence subsequent recruitment, but not as modeled in the Beverton-Holt or Ricker functions with a one-year lag and the pre-specified von Bertalanffy growth.

U.S. State Practice

Abstract This article summarizes U.S. State practice in the area of maritime enforcement. Focusing on the activities of the U.S. Coast Guard and the U.S. Navy, the article covers law enforcement for piracy and human trafficking, law enforcement for maritime terrorism and weapon trafficking, enforcement against illegal extraction of living marine resources, enforcement to protect the marine environment from pollution, enforcement to prevent accidents at sea, customs and illegal immigration enforcement, and drug trafficking enforcement. The article notes that the U.S. approach to maritime enforcement has been a “long-arm” approach ensuring enforcement of U.S. interests spanning oceanic regions.

Implementation challenges of area-based management tools (ABMTs) for biodiversity beyond national jurisdiction (BBNJ)

Area-based management tools (ABMTs), including marine protected areas (MPAs) are widely recognized as a key mechanism for conserving and restoring biodiversity. The developing international legally-binding instrument (ILBI) on biodiversity beyond national jurisdiction (BBNJ) is considering a range of approaches to ABMTs. While the process is still in early stages, this paper looks ahead to anticipate implementation challenges for ABMTs, given previous experiences with regional fisheries management organizations (RFMOs) and high seas MPAs. Drawing on the implementation of MPAs under the OSPAR Convention and the Convention on the Conservation of Antarctic Living Marine Resources (CCAMLR), key suggestions revolve around: (1) improving the evidence basis for protecting BBNJ, (2) designing effective compliance and enforcement mechanisms, and (3) engaging adequately with relevant stakeholders. In addition to the case studies, which are primarily marine pollution and fishing-oriented, considerations related to mitigating the effects of deep sea mining and the harvesting of marine genetic resources are also touched upon.

Dependence of bottlenose dolphin (Tursiops truncatus) auditory brainstem responses on noise burst rise time, amplitude, and envelope shape

A series of experiments examined the dependence of dolphin auditory brainstem response (ABR) peak amplitudes and latencies by stimulus level, rise times, and envelope shape. Stimuli were spectrally “pink” noise bursts with frequency content from 10 to 160 kHz, rise times that varied from 32 μs to 4 ms, and plateau sound pressure levels from 102 to 138 dB re 1 μPa. Cosine and cosine-cubed rise (and fall) envelopes were tested, and results were compared to those obtained for dolphins using noise bursts with linear rise envelopes [Finneran et al., J. Acoust. Soc. Am. 143, 2914–2921 (2018)]. Results for the cosine and cosine-cubed envelopes showed that ABR peak amplitudes were a function of envelope sound pressure at the end of a fixed integration window of approximately 260 μs. This is congruent with the previous findings for linear envelopes. The ABR peak latencies for the cosine and cosine-cubed envelopes were dependent on the second derivative of the envelope pressure function, as opposed to the first derivative of the pressure function for linear envelopes. These data are consistent with single-unit and nearfield response data for terrestrial mammals. [Work supported by Navy Living Marine Resources and SSC Pacific Naval Innovative Science and Engineering Programs.]

The production and reception of underwater sound in Hawaiian monk seals (Neomonachus schauinslandi)

The endangered Hawaiian monk seal is a primitive phocid (true) seal endemic to the tropical Hawaiian Islands. At present, there is a lack of substantive bioacoustic information available for this species, with no formal descriptions of underwater vocalizations and limited data concerning underwater hearing. To address these knowledge gaps, we are working to better understand species-typical auditory capabilities and sound production by thoroughly evaluating a single individual living in human care. A mature male monk seal was trained to perform an auditory go/no-go signal detection task in water. Detection thresholds were measured for narrowband tones across the frequency range of hearing to generate a full underwater audiogram. Additionally, an acoustic recorder was placed in this monk seal’s living enclosure for a full year, enabling characterization of his underwater repertoire and seasonal trends in vocal behavior. This study presents the first examination of underwater vocalizations in Hawaiian monk seals, provides insight into the perceptual abilities of this species and the evolution of underwater hearing within the phocid lineage, and enables improved assessments of noise effects on these vulnerable seals. [Work supported by Navy’s Living Marine Resources Program.]

The Other Australia/Japan Living Marine Resources Dispute: Inferences on the Merits of the Southern Bluefin Tuna Arbitration in Light of the Whaling Case, written by Andrew Serdy

The Other Australia/Japan Living Marine Resources Dispute: Inferences on the Merits of the Southern Bluefin Tuna Arbitration in Light of the Whaling Case, written by Andrew Serdy

Parameter estimation using randomized phases in an integrated assessment model for Antarctic krill.

An integrated model assessing the status and productivity of Antarctic krill (Euphausia superba, hereafter krill) was configured to estimate different subsets of 118 potentially estimable parameters in alternative configurations. We fixed the parameters that were not estimated in any given configuration at pre-specified values. The model was fitted to over forty years of fisheries and survey data for krill in Subarea 48.1, a statistical reporting area around the Antarctic Peninsula used by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR). The number of estimated parameters was gradually increased across model configurations. Configurations that estimated more parameters fitted the data better, but the order in which the parameters were estimated became more important in finding the best fit. Twenty-two configurations estimating from 48 to 107 parameters were able to obtain an invertible Hessian matrix that was subsequently used to estimate parameter uncertainty. Parameter uncertainties calculated using asymptotic approximation around the maximum likelihood estimates were often larger than uncertainties based on Markov chain Monte Carlo sampling for the same parameters. Diagnostics applied to MCMC samples in the best model of each configuration that obtained an invertible Hessian indicated that the most highly parameterized configurations did not reach stationary distributions. A 96-parameter configuration was the best fitting model of those that passed the MCMC diagnostics. The ΔAIC and ΔBIC scores indicated essentially no support relative to the best model for the alternative models that also passed MCMC diagnostics. Simulated data using the configurations as operating models showed that while all configurations passed "self-tests" for spawning biomass and recruitment, there was a small negative bias due to model penalties in the fishing mortality estimates for years with the highest fishing mortalities. "Cross-tests" of configurations that estimated different parameters often differed from the operating model values.

The “Commons” Discourse on Marine Fisheries Resources: Another Antecedent to Hardin’s “Tragedy”

Abstract Throughout the fifty years since its publication, Hardin’s “The Tragedy of the Commons” has been regarded as a seminal paper in the environmental movement, although his emphasis on population control (which actually formed the core concern of the article) has been largely forgotten. Hardin argued that free access by a growing population to common resources would inevitably lead to the depletion of those resources, citing as one example how maritime nations’ belief in the freedom of the seas, combined with their belief in the inexhaustibility of marine resources, had brought whales and many species of fish close to extinction. Hardin failed, however, to take account of the extensive debates throughout much of the twentieth century by scientists and policymakers on the general problem of the ocean commons — what they generally termed the “dilemma of the commons” — as it applied not only to living marine resources but also to mineral resources. By mid-century, as improved fishing technology gave rise to ever greater catches, the notion of the inexhaustibility of fisheries was largely discredited; hence scientists as well as experts in both national and international law became focused on addressing the dilemma of the commons through fisheries management, and specifically by determining the Maximum Sustainable Yield. Some economists, arguing instead for maximum efficiency, urged that open access be abandoned in favor of limited entry. Such measures to resolve the dilemma of the commons were the subject of numerous conferences (including the second UN Conference on the Law of the Sea in 1958) and were widely debated in scholarly publications and, indeed, by the late 1960s had been practically implemented by a number of laws and treaties. By 1966, national control over a twelve-mile fishing zone offshore of coastal nations had been well established. These developments regarding the oceans commons, predating Hardin’s article, were apparently either of no interest to him or (if he knew of them) purposefully subordinated to his main polemical objective, which was his Malthusian analysis of the commons issue and his call for limits on “human breeding.”

Two Recent Massive Breeding Failures in an Adélie Penguin Colony Call for the Creation of a Marine Protected Area in D'Urville Sea/Mertz

In the d’Urville Sea in East Antarctica, a population of roughly 20,000 pairs of Adelie penguins of Iles des Petrels (Terre Adelie) has experienced two massive breeding failures, with no chick surviving the 2013–14 and 2016–17 breeding seasons. In both seasons the extent of sea ice in front of the colony persisted throughout the breeding cycle of the birds. The timing of sea-ice recession differed greatly between seasons and the absence of polynya in a crucial phase of the cycle were paramount in driving these failures. The change in the icescape in front of Ile des Petrels following the calving of the Mertz glacier in 2010, together with increase in precipitations and changes in sea-ice firmness explain this situation and are discussed in the present manuscript. To prevent additional future impacts on this colony, like competition with fisheries for instance, we strongly support a scientific research zone in the d’Urville Sea—Mertz area, one of the three zones of proposed Marine Protected Area in East Antarctica to the Commission for the Conservation of Antarctic Marine Living Resources.

Poaching in Andaman and Nicobar coasts: insights

Tropical marine Islands are home to rich and highly endemic biodiversity because of their geographical seclusion. The geographical isolation supports the biodiversity against anthropogenic activities despite being vulnerable to natural disasters. Marine Islands hosts invaluable marine resources such as coral reefs, seagrass beds, mangroves and its associated fisheries which play an important role in livelihood of the coastal communities through tourism and fishing. It is important to judiciously protect and manage these islands to conserve the rich terrestrial and marine biodiversity it hosts. Andaman and Nicobar Islands (ANI), India is a strategically located linear chain of 572 tropical Islands located in Bay of Bengal in close proximity to South East Asian (SEA) countries such as Myanmar, Thailand and Indonesia. This proximity attracts poachers from SEA countries for harvesting living marine resources in the Exclusive Economic Zone (EEZ) of ANI posing significant threat to marine biodiversity and coastal security. Prudent approaches are required to address the issue of poaching by involving various stakeholders and a science-policy interface at regional level. Implementation of efficient and reliable monitoring-reporting systems could be worthy to address the issue of poaching. Mobile apps help lines, fishermen groups, aerial vehicles, Monitoring, Control and Surveillance (MCS) system and other satellite based tools can effectively deter poaching and illegal fishing. The importance of community participation and the ways through which the modern tools and community participation could compliment in curbing the incidences of poaching were discussed. Necessary precautionary approaches are essential at this point in ANI as it was understood through the review that poachers have gone down in recent years and this period could be effectively utilized towards planning and efficient management of such incidences in future. The status of poaching and its associated activities over these years and the possibilities on implementation of suitable monitoring and reporting systems in collaboration with stakeholders were discussed.

The shore is the limit: marine spatial protection in Antarctica under Annex V of the Environmental Protocol to the Antarctic Treaty

ABSTRACT This paper examines the role of the Protocol on Environmental Protection to the Antarctic Treaty in relation to marine spatial protection, with a focus on the designation of marine or partially marine areas as Antarctic Specially Protected or Managed Areas (ASPAs and ASMAs). For an improved understanding of this ASPA and ASMA practice, the competence arrangements between the Antarctic Treaty Consultative Meeting (ATCM) and the Commission on the Conservation of Antarctic Marine Living Resources (CCAMLR) are also examined. Five categories of ASPAs and ASMAs are identified according to their location and values relative to marine environments and ecosystems. A series of maps illustrate the outcomes of this inventory. The analysis and maps show that the use of ASPAs and ASMAs in marine or partially marine areas has been limited, although such protection is clearly within the mandate and competence of the Antarctic Treaty Consultative Parties. In part to explain these outcomes, the paper examines some recent ATCM discussions on marine protection issues. It is concluded that stronger spatial marine protection through ASPAs and ASMAs, as well as a strengthened integrated protection of the marine environment, requires stronger collaboration between the ATCM and CCAMLR, as well as mutual respect between these bodies.

Spatial variability and abundance pattern of Indian squid off Maharashtra coast, India

An analysis was carried out on monthly spatial distribution and unusual congregation of Indian squid (Uroteuthis (Photololigo) duvaucelii) off Maharashtra coast. Decadal, annual and monthly squid landing data were taken from National Marine Living Resources Data Centre (NMLRDC) of ICAR-CMFRI. Onboard fisheries information were collected from multi-day trawlers operating from Mumbai and Ratnagiri. Ocean environment parameters coming from Copernicus Marine Service Information with 1/12 degree horizontal resolution and 50 vertical depth level and OSCAR (Ocean Surface Current Analysis Real-time) near-surface ocean current estimates was derived using quasi-linear and steady flow momentum equations on a 1/3 degree grid with a 5 day resolution. In last decade, contribution of squid to total marine fish landing of Maharashtra rose from 2% to 7.3%. The decadal landing shows two peaks in 2012 and 2017. Indian squid landing in 2017 shows two peak, one during August to October confined to 150 N to 170 N latitude in 15 to 60 m depth off south Maharashtra and second in summer, during March-April months widely scattered in north and south Maharashtra. The unusual abundance of Indian squid during mid-October to mid- November 2017 were attributed to rise in coastal surface and subsurface temperature. Catch per hour of trawl and SST shows strong positive correlation (0.79) during the same period.

BÀN VỀ ĐIỀU TRA NGHỀ CÁ THƯƠNG PHẨM Ở BIỂN VIỆT NAM

In fish stock assessment, two approaches have been used to collect data: Fisheries independent survey and fisheries survey. Fisheries independent survey provides scientific information on species composition, catch rate, density, distribution, standing stock biomass and biological information of certain species while fisheries survey supplies primary data for a wide variety of statistical analysis of fisheries performance. In Vietnam, fisheries survey was first developed by project “Assessment of the Living Marine Resources in Vietnam” with the support of DANIA since 1998 as the pilot study in 11 coastal provinces with the purpose of establishing the fisheries statistical system in Vietnam. After the pilot stage, it has been extended to all of 28 coastal provinces and worked effectively since 2000. In 2006, when the project ended, the fisheries statistical system collapsed due to no finance support to continue. Since July 2014, the fisheries data collection network has been recovered with the collaboration of Directorate of Fisheries, Research Institute for Marine Fisheries and Provincial Departments of Capture Fisheries and Marine Resources Protection. The survey design was the logbook base with applying the sampling in space and in time method. This is an overview of the capture fisheries survey in Vietnam with its limitations and challenges.

Economic and Legal Mechanisms for Harnessing Natural Resource Potential of the Arctic in the Context of Food and Environmental Security

The article presents the methodology for the assessment of the resource potential of the Arctic. The authors analyze the main elements of its economy that are involved in the food supply of both the Arctic regions and the whole country, as well as in export-import transactions. We state facts and figures for the implementation of the Arctic States policies with the field of both potentials in the Northern latitudes and the projects for utilizing living marine resources in previously unexplored waters. We reveal the dependence of the use of Arctic resources from geopolitical, economic and technological changes in the world. Previously, the economic activities in the Artic were conditioned by certain legal regimes. Now it may revised because of the differences in conceptual approaches when determining the external borders and delimitating continental shelf. We characterize the domestic model of Arctic exploration and the food supply system of territories. We identify the current problem of extraction of marine resources, their processing and delivery to the consumer. The intersectoral resource economy of the Arctic territories, the difficulties of fishery and fish processing, aquaculture production, the lack of support for local farms cultivating crops and producing of animal genetic resources are inherited from previous economic models. The basic features of the modern economy of the Arctic have significant country-specific differences depending on the policies that are implemented on one or another Arctic territory. This is manifested in the conditions created by the state as well as in the level of investment attractiveness and the quality of life. The factors affecting food security in Arctic areas are the following: the access to fishing stocks; support of the agricultural sector and rural households; the formation of state market mechanisms when creating interregional agrofood complexes; respect for animal genetic resources. We recommend enhancing the regulatory, institutional and economic opportunities of coastal regions, creating the conditions for competition development in the extraction and processing of natural resources in the Arctic.