Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
23
result(s) for
"Willette, Demian A"
Sort by:
Towards global traceability for sustainable cephalopod seafood
by
Elegbede, Isa
,
Veiga, Pedro
,
Markaida, Unai
in
Amphioctopus
,
Applications programs
,
Barcoding
2024
Cephalopods are harvested in increasingly large quantities but understanding how to control and manage their stocks, and tracking the routes of the consumption that exploits them, lag behind what has been developed for exploiting finfish. This review attempts to redress the imbalance by considering the status of the major cephalopod stock species and the traceability of cephalopod seafood along the trade value chain. It begins with a general overview of the most important exploited cephalopods, their stock status and their market. Four major cephalopod resources are identified: the three squid species
Todarodes pacificus
,
Dosidicus gigas
and
Illex argentinus
; and one species of octopus,
Octopus vulgaris
. The techniques and problems of stock assessment (to assess sustainability) are reviewed briefly and the problems and possible solutions for assessing benthic stock such as those of octopuses are considered. An example of a stock well managed in the long term is presented to illustrate the value of careful monitoring and management: the squid
Doryteuthis gahi
available in Falkland Islands waters. Issues surrounding identification, mislabelling and illegal, unreported and unregulated (IUU) fishing are then reviewed, followed by a discussion of approaches and techniques of traceability as applied to cephalopods. Finally, some of the mobile apps currently available and in development for tracking seafood are compared. This review concludes with observations on the necessity for the strengthening and international coordination of legislation, and more rigorous standards for seafood labelling and for taxonomic curation of DNA sequences available in public databases for use in seafood identification.
Journal Article
The Tropical Seagrass Halophila stipulacea: Reviewing What We Know From Its Native and Invasive Habitats, Alongside Identifying Knowledge Gaps
by
Engelen, Aschwin H
,
Azcárate-García, Tomás
,
Beca-Carretero, Pedro
in
alien species
,
Biology
,
Caribbean Sea
2020
Halophila stipulacea is a small tropical seagrass, native to the Red Sea, Persian Gulf, and the Indian Ocean. It invaded the Mediterranean Sea 150 years ago as a Lessepsian migrant, but so far has remained in insulated, small populations across this basin. Surprisingly, in 2002 it was reported in the Caribbean Sea, where within less than two decades it spread to most of the Caribbean Island nations and reaching the South American continent. Unlike its invasion of Mediterranean, in the Caribbean H. stipulacea creates large, continuous populations in many areas. Reports from the Caribbean demonstrated the invasiveness of H. stipulacea by showing that it displaces local Caribbean seagrass species. The motivation for this review comes from the necessity to unify the existing knowledge on several aspects of this species in its native and invasive habitats, identify knowledge gaps and develop a critical strategy to understand its invasive capacity and implement an effective monitoring and conservation plan to mitigate its potential spread outside its native ranges. We systematically reviewed 164 studies related to H. stipulacea to create the \"Halophila stipulacea database.\" This allowed us to evaluate the current biological, ecological, physiological, biochemical, and molecular knowledge of H. stipulacea in its native and invasive ranges. Here we (i) discuss the possible environmental conditions and plant mechanisms involved in its invasiveness, (ii) assess the impact of H. stipulacea on native seagrasses and ecosystem functions in the invaded regions, (iii) predict the ability of this species to invade European and transoceanic coastal waters, (iv) identify knowledge gaps that should be addressed to better understand the biology and ecology of this species both in its native and non-native habitats, which would improve our ability to predict H. stipulacea's potential to expand into new areas in the future. Considering the predicted climate change scenarios and exponential human pressures on coastal areas, we stress the need for coordinated global monitoring and mapping efforts that will record changes in H. stipulacea and its associated communities over time, across its native, invasive and prospective distributional ranges. This will require the involvement of biologists, ecologists, economists, modelers, managers, and local stakeholders
Journal Article
Hidden Diversity in Sardines: Genetic and Morphological Evidence for Cryptic Species in the Goldstripe Sardinella, Sardinella gibbosa (Bleeker, 1849)
by
Santos, Mudjekeewis D.
,
Willette, Demian A.
,
Carpenter, Kent E.
in
Analysis
,
Animals
,
Archipelagoes
2014
Cryptic species continue to be uncovered in many fish taxa, posing challenges for fisheries conservation and management. In Sardinella gibbosa, previous investigations revealed subtle intra-species variations, resulting in numerous synonyms and a controversial taxonomy for this sardine. Here, we tested for cryptic diversity within S. gibbosa using genetic data from two mitochondrial and one nuclear gene regions of 248 individuals of S. gibbosa, collected from eight locations across the Philippine archipelago. Deep genetic divergence and subsequent clustering was consistent across both mitochondrial and nuclear markers. Clade distribution is geographically limited: Clade 1 is widely distributed in the central Philippines, while Clade 2 is limited to the northernmost sampling site. In addition, morphometric analyses revealed a unique head shape that characterized each genetic clade. Hence, both genetic and morphological evidence strongly suggests a hidden diversity within this common and commercially-important sardine.
Journal Article
Editorial: Seagrasses Under Times of Change
by
Reuter, Hauke
,
Willette, Demian A.
,
Teichberg, Mirta
in
Beaches
,
Carbon sequestration
,
climate change
2022
Degradation of seagrass ecosystems entails the loss of the associated biota, primary productivity, and local fisheries, and increased sediment re-suspension and beach erosion, processes that result in severe ecological and socio-economic consequences not only for seagrass meadows but also for neighboring ecosystems and human inhabitants (Erftemeijer and Lewis,2006; Joseph et al.,2019; Moksnes et al.,2021). Studies in this Research Topic have highlighted that coexisting species (even in the same meadow) assert different responses to stress or resilience capacity due to their different life-history traits. [...]it was shown that the same species growing in different environments or coming from different geographic areas can have contrasting responses to the same stress. [...]the conservation and management of seagrass meadows will depend on local studies that focus on the responses and resilience of the specific species and populations in the area. Modeling species distribution under future temperature and salinity conditions project an increase in invasive species and a dramatic change of species composition in an exemplary study for the Mediterranean.
Journal Article
Molecular identification of critically endangered European eels ( Anguilla anguilla ) in US retail outlets
by
Willette, Demian A.
,
Ely, Taylor
,
Spencer, Erin T.
in
18S rDNA
,
Anguilla - genetics
,
Anguilla anguilla
2023
The European eel ( Anguilla anguilla ) has declined by over 90% since the early 1980s and has been listed as critically endangered. Yet, despite strict export bans from the European Union, the European eel is still sold illegally in many countries. Efforts to monitor the trade of European eels have been primarily concentrated in Asian markets where concerningly high rates of European eel have been reported. Comparably fewer studies have assessed the identities of eel samples from the United States (US), despite the obvious implications for eel conservation. To address this knowledge gap, we purchased 137 eel products (134 freshwater eels and three saltwater eels) from grocers, sushi bars, and restaurants in nine states across the US from 2019 to 2021. Seven samples (5.2%) labeled as freshwater eels (or “unagi”) were identified as European eels using a combination of mitochondrial (cytochrome b) and nuclear (18S rRNA) restriction digestion assays, a fast and inexpensive molecular tool for seafood identification that can identify hybrids between European eels ( A. anguilla ) and American eels ( A. rostrata ). No hybrids between European and American eels were found and all seven samples identified with restriction digestion as European eels were confirmed by sequencing of cytochrome b and 18S rRNA. Frequency of European eels in US markets did not significantly correlate with state or retail type. Although illegal eel exports are likely reaching US consumers, the frequency of European eel samples in this study of the US market is much lower than found in other non-European countries.
Journal Article
Investigating Los Angeles’ urban roadway network from a biologically-formed perspective
by
Willette, Demian A.
,
Deen, Sophia
,
Kuzmenko, Tatiana
in
3D printing
,
Biogeography
,
Biological network
2020
The evolution of networks is constrained by spatial properties of the environment; a characterization that is true in both biological and built networks. Hence built networks such as urban streets can be compared to biological networks to reveal differences in efficiency and complexity. This study assessed foraging networks created by the slime-mold Physarium polycephalum on proportional 3D-printed topographic maps of metropolitan city of Los Angeles, California. Rapidly-generated isomorphic solutions were found to be consistently and statistically shorter than existing roadways in system length. Slime mold also allocated resources to supporting key nodes, analogous to how heavy traffic flows through major intersections. Further, chemical deterrents inhibited exploration of slime mold in selected areas and allows for testing of network redundancy and system resilience, such as after an earthquake or wildfire.
Journal Article
Characterizing Industrial and Artisanal Fishing Vessel Catch Composition Using Environmental DNA and Satellite-Based Tracking Data
by
Sotil, Giovanna
,
Willette, Demian A
,
Gold, Zachary
in
Accuracy
,
artisanal fishing
,
Bioinformatics
2021
The decline in wild-caught fisheries paired with increasing global seafood demand is pushing the need for seafood sustainability to the forefront of national and regional priorities. Validation of species identity is a crucial early step, yet conventional monitoring and surveillance tools are limited in their effectiveness because they are extremely time-consuming and require expertise in fish identification. DNA barcoding methods are a versatile tool for the genetic monitoring of wildlife products; however, they are also limited by requiring individual tissue samples from target specimens which may not always be possible given the speed and scale of seafood operations. To circumvent the need to individually sample organisms, we pilot an approach that uses forensic environmental DNA (eDNA) metabarcoding to profile fish species composition from the meltwater in fish holds on industrial and artisanal fishing vessels in Ecuador. Fish identified genetically as present were compared to target species reported by each vessel’s crew. Additionally, we contrasted the geographic range of identified species against the satellite-based fishing route data of industrial vessels to determine if identified species could be reasonably expected in the catch.
Journal Article
Using DNA barcoding to track seafood mislabeling in Los Angeles restaurants
2017
Seafood mislabeling is common in both domestic and international markets. Studies on seafood fraud often report high rates of mislabeling (e.g., > 70%), but these studies have been limited to a single sampling year, which means it is difficult to assess the impact of stricter governmental truth-in-labeling regulations. We used DNA barcoding to assess seafood labeling in 26 sushi restaurants in Los Angeles over 4 years. Seafood from 3 high-end grocery stores were also sampled (n — 16) in 2014. We ordered 9 common sushi fish from menus, preserved tissue samples in 95% ethanol, extracted the genomic DNA, amplified and sequenced a portion of the mtDNA COI gene, and identified the resulting sequence to known fish sequences from the National Center for Biotechnology Information nucleotide database. We compared DNA results with the U.S. Food and Drug Administration (FDA) list of acceptable market names and retail names. We considered sushi-sample labels that were inconsistent with FDA names mislabeled. Sushi restaurants had a consistently high percentage of mislabeling (47%; 151 of 323) from 2012 to 2015, yet mislabeling was not homogenous across species. Halibut, red snapper, yellowfin tuna, and yellowtail had consistently high (< 77%) occurrences of mislabeling on menus, whereas mislabeling of salmon and mackerel were typically low (> 15%). All sampled sushi restaurants had at least one case of mislabeling. Mislabeling of sushi-grade fish from high-end grocery stores was also identified in red snapper, yellowfin tuna, and yellowtail, but at a slightly lower frequency (42%) than sushi restaurants. Despite increased regulatory measures and media attention, we found seafood mislabeling continues to be prevalent. La mala etiquetación de pescados es común tanto en los mercados domésticos como en los internacionales. Los estudios sobre el fraude de pescados generalmente reportan tasas altas de mala etiquetación (p. ej.: >70 %), pero estos estudios han sido limitados a un sólo muestreo al año, lo que significa que es complicado evaluar el impacto de regulaciones gubernamentales más estrictas sobre las etiquetas verídicas. Utilizamos el código de barras de ADN para evaluar el etiquetado de pescados en 26 restaurantes de sushi en Los Ángeles durante cuatro años. Los pescados de tres supermercados lujosos también fueron muestreados (n = 16) en el 2014. Ordenamos nueve pescados comunes en el sushi de los menús, preservamos las muestras de tejido en etanol al 95 %, extrajimos el ADN genómico, amplificamos y secuenciamos la porción del gen COIdelADNmt, e identificamos la secuencia resultante a partir de secuencias de peces de la base de datos de nucleótidos del Centro Nacional para la Información Biotecnológica. Comparamos los resultados de ADN con la lista de nombres aceptables para el mercado y de venta al menudeo de la Administración Estadunidense de Alimentos y Medicamentos (FDA, en inglés). Consideramos como mal etiquetadas a las muestras de sushi que no fueron consistentes con los nombres de la FDA. Los restaurantes de sushi tuvieron constantemente un porcentaje alto de mala etiquetación (47 %; 151 de 323) de 2012 a 2015, sin embargo, la mala etiquetación no fue homogénea entre las especies. El hipogloso, el huachinango, el atún de aleta amarilla y el jurel tuvieron ocurrencias altas (<77 %) de mala etiquetación en los menús, mientras que la mala etiquetación del salmón y la caballa fue típicamente baja (>15 %). Todos los restaurantes de sushi muestreados tuvieron por lo menos un caso de mala etiquetación. La mala etiquetación de pescado con calidad para sushi de los supermercados lujosos también fue identificada para el huachinango, el atún de aleta amarilla y el jurel, pero a una frecuencia un poco menor (42 %) que en los restaurantes de sushi. A pesar del incremento en las medidas regulatorias y en la atención de los medios, encontramos que la mala etiquetación de los pescados todavía es prevalente.
Journal Article
Delivering on seafood traceability under the new U.S. import monitoring program
by
Willette, Demian A.
,
Cheng, Samantha H.
in
Animals
,
Appropriate technologies
,
Appropriate technology
2018
The United States is the world’s largest fish importer. Recent reports, however, indicate that 25–30% of wild-caught seafood imported into the US is illegally caught, heightening concerns over the country’s significant role in driving Illegal, Unreported, and Unregulated (IUU) fishing. In January 2017, NOAA enacted the Seafood Import Monitoring Program in an effort to combat IUU fishing through mandating improved seafood traceability requirements. This program requires reporting of fisheries data from harvest to arrival at the US border. Given the role of the US as a major global importer of seafood, this regulation could be a transformative action on fisheries worldwide if implementation includes two key components—(1) applying best available and most appropriate technologies and (2) building monitoring and enforcement capacity among trading nations. This paper provides insightful commentary on the potential for this US policy to lead by example and improve an essential natural resource that over a billion people worldwide depend on for nutrition and livelihoods.
Journal Article
DNA barcoding cannot discriminate between Sardinella tawilis and S. hualiensis (Clupeiformes: Clupeidae)
by
Santos, Mudjekeewis D.
,
Fontanilla, Ian Kendrich C.
,
Luczon, Adrian U.
in
Cytochrome
,
Cytochrome b
,
Cytochrome-c oxidase
2019
Sardinella tawilis, the only known freshwater sardinella in the world, is endemic to Taal Lake, Philippines. Previous studies found the Taiwan sardinella, S. hualiensis, to be morphologically very similar to S. tawilis and identified it as the marine sister species of S. tawilis. In this study, DNA barcoding using the mitochondrial cytochrome c oxidase I (COI) gene was carried out to analyze species demarcation in the Sardinella genus, focusing primarily on the relationship between S. tawilis and S. hualiensis. The neighbour-joining (NJ) tree that was constructed using Kimura 2-parameter (K2P) model showed a single clade for the two species with 100% bootstrap support. K2P interspecific genetic divergence ranged from 0% to 0.522%, which is clearly below the suggested 3-3.5% cutoff for species discrimination. Recombination activating gene 1 (RAG1), mitochondrial control region (CR), cytochrome b, 16S rRNA, and S7 markers were used to further validate the results. Sardinella tawilis and S. hualiensis clustered together with a bootstrap support of 99-100% in each of the NJ trees. Low interspecific genetic distances between S. tawilis and S. hualiensis for all the markers except CR could be attributed to incipient allopatric speciation.
Journal Article