Island Fish Research Articles

Limitations of quartz extracted from Antarctica sediments for luminescence dating

Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL) properties of quartz samples extracted from soil of Fisher Island (76° 13ʹ 23.9ʺ E, 69° 23ʹ 31.9ʺ S) in Antarctica were studied. The nature of signals indicated presence of a dominant slow component in the OSL signal. The widely utilized Single Aliquot Regenerative (SAR) protocol for dose recovery was found unsuitable for this particular sample due to the dominating slow component in the OSL signal. Efforts to minimize the effect of slow component in dose recovery by adopting procedures like, bleaching with blue light, and early background subtraction were carried out. Additionally, thermally transferred OSL (TT-OSL) studies were conducted on the natural sample and dose estimation using the TT-OSL SAR protocol was carried out.

Taxonomic diversity of fishes from two coral-reef waters of the South China Sea

Context Conservation of coral-reef fishes requires an understanding of their spatial and temporal responses to climate change and anthropogenic disturbance, which also requires an understanding of patterns in their taxonomic diversity. Aims To describe the species composition, taxonomic diversity and G-F diversity-measurement index of Qilianyu Island and Meiji Reef, South China Sea, coral-reef fish assemblages. Methods Coral reef-dwelling fish were sampled in 2018 and 2019 at Meiji Reef and Qilianyu Island by using various fishing gears, identified to the lowest taxonomic category, and their taxonomic relatedness was compared at levels of class, order, family, genus and species. Key results The reef-dwelling fish fauna of this region comprises 123 species in 5 orders (dominated by Perciformes, at 78%), 22 families and 46 genera. The average taxonomic distinctness (Δ+) of Qilianyu Island fish assemblages is 55.52, and variation in taxonomic distinctness (Λ+) is 138.18; for Meiji Reef, values for Δ+ and Λ+ are 53.02 and 135.33 respectively. Conclusions High species diversity and low taxonomic diversity are important features of coral-reef fish assemblages in the South China Sea. Implications The high species diversity of reef fish in the South China Sea, along with a well-distributed assemblage of families and genera, is crucial for preserving the region’s fish biodiversity. Consequently, timely prioritisation of reef fish conservation is essential.

Risk assessment for seafood consumers exposed to mercury and other trace elements in fish from Long Island, New York, USA

We determined concentrations of Hg, Pb, Cd, Cr, As, Ni, Ag, Se, Cu, and Zn in muscle tissue of six commonly consumed Long Island fish species (black seabass, bluefish, striped bass, summer flounder, tautog, and weakfish, total sample size = 1211) caught off Long Island, New York in 2018 and 2019. Long-term consumption of these coastal fish could pose health risks largely due to Hg exposure; concentrations of the other trace elements were well below levels considered toxic for humans. By combining the measured Hg concentrations in the fish (means ranging from 0.11 to 0.27 mg/kg among the fish species), the average seafood consumption rate, and the current US EPA Hg reference dose (0.0001 mg/kg/d), it was concluded that seafood consumption should be limited to four fish meals per month for adults for some fish (bluefish, tautog) and half that for young children. Molar ratios of Hg:Se exceeded 1 for some black seabass, bluefish, tautog, and weakfish.

Lessons from a Landscape Irrigation Rebate Program in Miami Dade County

We calculated savings in outdoor water uses from 37 properties in Fisher Island, Florida, that were retrofitted with smart Evapotranspiration-based irrigation controllers through the Miami Dade County’s Landscape Irrigation Rebate Program. We found average water savings of 11.4 million gallons per year from the 37 properties on the island. We discuss the roles of extension personnel in developing and effectively managing an irrigation rebate program and the implications of results from this program for large scale efforts towards efficient use of freshwater resources.

Identification of Arctic Food Fish Species for Anthropogenic Contaminant Testing Using Geography and Genetics.

The identification of food fish bearing anthropogenic contaminants is one of many priorities for Indigenous peoples living in the Arctic. Mercury (Hg), arsenic (As), and persistent organic pollutants including polychlorinated biphenyls (PCBs) are of concern, and these are reported, in some cases for the first time, for fish sampled in and around King William Island, located in Nunavut, Canada. More than 500 salmonids, comprising Arctic char, lake trout, lake whitefish, and ciscoes, were assayed for contaminants. The studied species are anadromous, migrating to the ocean to feed in the summers and returning to freshwater before sea ice formation in the autumn. Assessments of muscle Hg levels in salmonids from fishing sites on King William Island showed generally higher levels than from mainland sites, with mean concentrations generally below guidelines, except for lake trout. In contrast, mainland fish showed higher means for As, including non-toxic arsenobetaine, than island fish. Lake trout were highest in As and PCB levels, with salmonid PCB congener analysis showing signatures consistent with the legacy of cold-war distant early warning stations. After DNA-profiling, only 4–32 Arctic char single nucleotide polymorphisms were needed for successful population assignment. These results support our objective to demonstrate that genomic tools could facilitate efficient and cost-effective cluster assignment for contaminant analysis during ocean residency. We further suggest that routine pollutant testing during the current period of dramatic climate change would be helpful to safeguard the wellbeing of Inuit who depend on these fish as a staple input to their diet. Moreover, this strategy should be applicable elsewhere.

A baseline for POPs contamination in Australian seabirds: little penguins vs. short-tailed shearwaters

While globally distributed throughout the world's ecosystems, there is little baseline information on persistent organic pollutants (POPs) in marine environments in Australia and, more broadly, the Southern Hemisphere. To fill this knowledge gap, we collected baseline information on POPs in migratory short-tailed shearwaters (Ardenna tenuirostris) from Fisher Island, Tasmania, and resident little penguins (Eudyptula minor) from Phillip Island, Victoria. Levels of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and brominated flame retardants (BFRs) were determined from blood samples, with total contamination ranging 7.6-47.7 ng/g ww for short-tailed shearwaters and 0.12-46.9 ng/g ww for little penguins. In both species contamination followed the same pattern where PCBs>OCPs>BFRs. BFR levels included the presence of the novel flame retardant hexabromobenzene (HBB). These novel results of POPs in seabirds in southeast Australia provide important information on the local (penguins) and global (shearwaters) distribution of POPs in the marine environment.

Climate variability and breeding parameters of a transhemispheric migratory seabird over seven decades

Climate variability affects physical oceanographic systems and environmental conditions at multiple spatial and temporal scales. These changes can influence biological and ecological processes, from primary productivity to higher trophic levels. Short-tailed shearwaters Ardenna tenuirostris are transhemispheric migratory procellariiform seabirds that forage on secondary consumers such as fish (myctophids) and zooplankton (euphausiids). In this study, we investigated the breeding parameters of the short-tailed shearwater from a colony of 100 to 200 breeding pairs at Fisher Island, Tasmania, Australia, for the period 1950 to 2012, with the aim to quantify the relationship between breeding parameters with large-scale climate indices in the Northern (i.e. Northern Pacific Index and Pacific Decadal Oscillation) and Southern Hemispheres (i.e. El Niño-Southern Oscillation and Southern Annular Mode). Through the use of generalised linear models, we found that breeding participation among short-tailed shearwaters was affected by climate variability with a 12-mo temporal lag. Furthermore, breeding success decreased in years of increased rainfall at the colony. These findings demonstrate that both large-scale climate indices and local environmental conditions could explain some of the variability among breeding parameters of the short-tailed shearwater.

AGE AND GROWTH OF PACIFIC SAND LANCE (AMMODYTES PERSONATUS) AT THE LATITUDINAL EXTREMES OF THE GULF OF ALASKA LARGE MARINE ECOSYSTEM

The Pacific Sand Lance (Ammodytes personatus) is a major component of the forage base for many species of marine birds, mammals, and fishes. Despite its ecological importance, relatively little is known regarding basic biology or life-history parameters for this species. Information on age and growth is particularly lacking for Pacific Sand Lance in the Salish Sea, an inland sea that encompasses the San Juan Archipelago in Washington State. Here, we present information on age and growth of Pacific Sand Lance from this region and then contrast it with a previous study based in Cook Inlet, Alaska. These 2 regions comprise the latitudinal extremes of the Gulf of Alaska large marine ecosystem. We found evidence for possible differences in growth of Pacific Sand Lance between the 2 regions, with San Juan Island fish generally being smaller at age than fish in Cook Inlet. We interpret these results with respect to regional and temporal differences in environmental conditions and resource availability linked to duration and magnitude of seasonal production, which we hypothesize affects the period of winter dormancy employed by this species as a strategy to cope with resource limitation.

Variable prey consumption leads to distinct regional differences in Chinook salmon growth during the early marine critical period

Growth during the early marine critical period is positively associated with survival and recruitment for Pacific salmonOncorhynchusspp., so it is important to understand how certain foraging strategies may bolster growth in estuarine and marine environments. To elucidate how spatiotemporal and demographic differences in diet contribute to growth rate variability, we analyzed stomach contents in tandem with morphometric and hormonal indices of growth for subyearling Chinook salmonO. tshawytschacaptured in Puget Sound, Washington, USA. Regional dietary patterns indicated that fish caught in northern Puget Sound ate insects in the estuarine and nearshore habitats, followed by decapod larvae, euphausiids, or forage fish in the offshore zone. In southern Puget Sound, fish ate insects in the estuary but were more likely to eat mysids and other crustaceans in the nearshore zone. In the marine habitats adjacent to the San Juan Islands, subyearlings ate forage fish, and their stomachs were as much as 1.4 to 3 times fuller than salmon captured in other regions. Scale-derived growth rates and insulin-like growth factor-1 levels showed distinct growth advantages for San Juan Islands fish which were strongly associated with the early adoption of piscivory. However, consumption of larger crustaceans such as mysids and euphausiids was also associated with greater relative growth regardless of where individuals were captured. These findings highlight how spatiotemporal differences in prey quantity, prey profitability, and individual foraging strategies result in variable growth rates among salmon populations. Specifically, they emphasize the role of piscivory in promoting early marine growth for out-migrating Chinook salmon.

British Museum Ethnographic Photography at the 1936 International Surrealist Exhibition

As part of the 1936 International Surrealist Exhibition held at the New Burlington Galleries in London, ethnographic photographs of non-Western objects were taken at the British Museum and interspersed amongst Surrealist artwork. Ten photographs in total were used, spanning Solomon Island Fish Coffins to Congolese Nail Fetishes. The article analyses these photographs as sculptures and in terms of their significance to the 1936 exhibition display and their wider impact upon the Surrealist movement. It reveals that Paul Nash and Hugh Sykes Davies were responsible for the selection of the non-Western objects to be photographed. At the exhibition opening André Breton gave a transformative lecture, ‘Limites Non-Frontières du Surréalisme [Borderless limits of Surrealism]’ which conjoined notions of cosmopolitanism and the spirit. The inclusion of the British Museum photographs was clearly intended to aesthetically mirror the content of Breton’s speech. This article thus postulates that the Surrealists intended to propagate a cosmopolitan method of curation through a transcendence of taxonomic display mechanisms common to ethnographic museum environments, such as the very one the photographs were taken in. Moreover, the British Museum photographs chosen by the Surrealists all have religious and spiritual connotations. Such embodied manifestations are a particular brand of border crossing that should also be considered an element of a burgeoning discourse surrounding international Surrealism. Consequently, the oft-cited impact of Freud’s Totem and Taboo (1913) upon Surrealist ethnography, which denounces the totem as a precursor to religious belief and madness, is marginalised.

Preface: Celebration of the Career of Robert Nathan Ginsburg

Preface: Celebration of the Career of Robert Nathan Ginsburg

Semiautomated Detection and Mapping of Vegetation Distribution in the Antarctic Environment Using Spatial-Spectral Characteristics of WorldView-2 Imagery

Effective monitoring of changes in the geographic distribution of cryospheric vegetation requires high-resolution and accurate baseline maps. The rationale of the present study is to compare multiple feature extraction approaches to remotely mapping vegetation in Antarctica, assessing which give the greatest accuracy and reproducibility relative to those currently available. This study provides precise, high-resolution, and refined baseline information on vegetation distribution as is required to enable future spatiotemporal change analyses of the vegetation in Antarctica. We designed and implemented a semiautomated customized normalized difference vegetation index (NDVI) approach for extracting cryospheric vegetation by incorporating very high resolution (VHR) 8-band WorldView-2 (WV-2) satellite data. The viability of state-of-the-art target detection, spectral processing/matching, and pixel-wise supervised classification feature extraction techniques are compared with the customized NDVI approach devised in this study. An extensive quantitative and comparative assessment was made by evaluating four semiautomatic feature extraction approaches consisting of 16 feature extraction standalone methods (four customized NDVI plus 12 existing methods) for mapping vegetation on Fisher Island and Stornes Peninsula in the Larsemann Hills, situated on continental east Antarctica. The results indicated that the customized NDVI approach achieved superior performance (average bias error ranged from ~6.44 ± 1.34% to ~11.55 ± 1.34%) and highest statistical stability in terms of performance when compared with existing feature extraction approaches. Overall, the accuracy analysis of the vegetation mapping relative to manually digitized reference data (supplemented by validation with ground truthing) indicated that the 16 semi-automatic mapping methods representing four general feature extraction approaches extracted vegetated area from Fisher Island and Stornes Peninsula totalling between 2.38 and 3.72 km2 (2.85 ± 0.10 km2 on average) with bias values ranging from 3.49 to 31.39% (average 12.81 ± 1.88%) and average root mean square error (RMSE) of 0.41 km2 (14.73 ± 1.88%). Further, the robustness of the analyses and results were endorsed by a cross-validation experiment conducted to map vegetation from the Schirmacher Oasis, East Antarctica. Based on the robust comparative analysis of these 16 methods, vegetation maps of the Larsemann Hills and Schirmacher Oasis were derived by ensemble merging of the five top-performing methods (Mixture Tuned Matched Filtering, Matched Filtering, Matched Filtering/Spectral Angle Mapper Ratio, NDVI-2, and NDVI-4). This study is the first of its kind to detect and map sparse and isolated vegetated patches (with smallest area of 0.25 m2) in East Antarctica using VHR data and to use ensemble merging of feature extraction methods, and provides access to an important indicator for environmental change.

Effective co-management and long-term reef fish recovery from severe coral bleaching: Insights from Misali Island, PECCA, Tanzania

Misali, an uninhabited islet along the east coast of Pemba Island off the mainland Tanzanian coast, is a biodiversity hotspot and Marine Protected Area (MPA), consisting of a core non-extraction zone (NEZ) surrounded by a larger area where some artisanal fishing is allowed. Within a year of receiving official protection under a co-management agreement, the island underwent a catastrophic bleaching event in 1998, and funding and enforcement in the protected area have been inconsistent since a restructuring of management in 2006. In this study, we investigate current health of the island's fish community, and report 186 observed fish species. We estimate that, including unseen species and those outside the study area, the total species richness may be comparable to the historical baseline of 244 species; however, this represents a decline from the 270 species estimated in 2001 and the 350 species observed in 2004, after several years of successful protections. Patterns of species richness over time likely reflect changes in management effectiveness and engagement of Misali's fishing communities. Diversity of indicator (Chaetodontidae) and keystone (Scarinae) taxa were comparable to historical levels and greatest inside the NEZ, suggesting continued reef health and resilience. However, we found no other significant differences between fish communities inside and outside the NEZ, which observations indicate is poorly enforced, and the disproportionate loss of large predatory fish species may indicate overfishing. The case study of Misali suggests that a temporary reduction in fishing pressure while the island was recovering from a severe bleaching event may have had long-lasting benefits for reef health and resilience. For future management, we recommend consideration of species-specific protections, a possible re-designation of NEZ boundaries to include more unique habitat types, and reintegration of local fishing communities into MPA co-management.

Living in an amphidromous world: Perspectives on the management of fish passage from an island nation

Abstract Amphidromy is a form of migratory life history typified by the reproduction of fish in freshwater environments, the early downstream dispersal of post‐hatch larvae to marine environments, and the return of small‐bodied young juveniles to freshwater environments for growth to adulthood. Island freshwater fish communities are frequently dominated by fish species with amphidromous life histories. Amphidromous life cycles leave fish communities highly susceptible to habitat modification and disruptions to connectivity across marine and freshwater environments. This means that managing waterway connectivity is fundamental to their conservation; however, the unique and often geographically restricted amphidromous communities that characterize many small island nations have received little consideration in the development of strategies for the management of fish passage. The ecology and locomotory capabilities of amphidromous species are often poorly studied, partly because their small size at migratory life stages renders current state‐of‐the‐art in situ biotelemetry methods unsuitable. The small size of fish also means that seemingly small obstructions can severely impede migrations. The steps necessary to advance the management of fish passage for island fish communities are: curating and maintaining barrier inventories; evaluating barrier permeability; developing effective barrier mitigation options; and prioritizing restoration and conservation efforts. New methods for understanding the ecology and locomotory capabilities and behaviour of amphidromous fishes are required to advance the management of fish passage for island fish communities. Fish passage solutions that imitate natural streams, such as those promoted in new guidelines in New Zealand, may be the most effective way of improving waterway connectivity; however, integrated approaches to freshwater fish conservation that account for meta‐population dynamics, in combination with the management of fish passage, are necessary to optimize conservation outcomes for amphidromous species.

Drought Facilitates Species Invasions in an Urban Stream: Results From a Long-Term Study of Tropical Island Fish Assemblage Structure

The natural flow regime is a key regulator of the dynamics of stream communities and ecosystem processes. Native fish assemblages are evolutionarily adapted to their local flow regime. In the Caribbean, streams are vulnerable to changes in climate that will alter their flow regimes. We assessed long-term patterns in fish assemblages (2008-2016) in an urban stream in San Juan, Puerto Rico. We hypothesized that drought periods would result in negative effects on native fish species and positive effects on introduced species. Fish assemblages were sampled annually from 2008 to 2016 by backpack electrofishing, with additional sampling during 2015, which was a drought year. Cumulative dry season discharge was consistently over 300 m3/s from 2008 to 2013, except from 2014 to 2016 when it dropped below 170 m3/s. Thirteen species were found, including most native species reported for Puerto Rico and introduced species (e.g., Cichlids, Poeciliids, and Loracariids). Native species were dominant in abundance during most years, except during drought and post-drought sampling events when introduced species became dominant. Introduced species increased in richness with time from less than two species between 2008 and 2013 to seven in 2015. The increase in introduced species was mostly attributed to the appearance of several species of cichlids towards the end of the study. Cluster analysis divided the data set in two groups: drought and non-drought sampling events. Introduced cichlids and the native A. monticola accounted for more than 60% of assemblage dissimilarity. Fish assemblage abundance and richness were negatively related to several components of stream hydrology (e.g., cumulative daily stream discharge, the number of major floods). A significant change in size over time was found for the native A. monticola, which decreased in size during the drought period. Overall, our study documents drought-facilitated invasions by several aggressive and highly ecologically competitive species, highlights the importance of the natural flow regime as a source of environmental resilience to invasions in tropical island streams, and provides an example of how climate change has and will likely continue to alter Caribbean stream fish assemblages.

When new technology joins old documents and east meets west: virtually reconstructing the Fisher Island Pagoda Lighthouse (China)

<p>Located on the route between Xiamen and Taiwan (China), the Penghu (Pescadores Islands) are an archipelago and the site of a military garrison. The second largest island, Xiyu or Fisher Island, was accordingly an obvious point to build a navigational marker to guide sailors. Records indicate that some type of a marker, in the form of a tower or pagoda, was constructed in the 17thcentury. However, in 1778the original was replaced by a different sort of pagoda tower. The new structure has long been known to have been a purpose fully designed lighthouse. Although today’s Yuwengdao lighthouse, built in 1875, has become a famous heritage landmark, the earlier 1778 structure, it can be argued has greater heritage significance in that it was an entirely original creation preceding the introduction of western lighthouse technology in China by nearly a century. Thanks to the fortunate discovery of a hitherto unknown photograph of this earlier lighthouse backed by further research in early navigational documents, gazetteers, charts and inscriptions and The authors have been able to make a 3D virtual reconstruction using state-of-the-art Revit software and thus answer several research questions about this old lighthouse pagoda, including dimensions, location, orientation, function and materials.</p>

Movement patterns and spatial segregation of two populations of lake trout Salvelinus namaycush in Lake Huron

Abstract Movement ecology is an important component of life history and population dynamics, and consequently its understanding can inform successful fishery management decision-making. While lake trout populations in Lake Huron have shown signs of recovery from near extinction in recent years, knowledge of their movement behavior remains incomplete. We used acoustic telemetry to describe and compare movement patterns of two Lake Huron lake trout populations: Drummond Island and Thunder Bay. Both populations showed high spawning site fidelity, with no evidence of co-mingling during non-spawning season. Detections between spawning periods were mainly limited to receivers within 100 km of spawning locations, and suggested that the two populations likely remained segregated throughout the year. Drummond Island fish, which spawn inside the Drummond Island Refuge, primarily dispersed east into Canadian waters of Lake Huron, with 79–92% of fish being detected annually on receivers outside the refuge. In contrast, Thunder Bay fish tended to disperse south towards Saginaw Bay. Large proportions (i.e., > 80%) of both populations were available to fisheries outside the management zone containing their spawning location. Thunder Bay fish moved relatively quickly to overwinter habitat after spawning, and tended to repeat the same post-spawning movement behavior each year. The consistent, predictable movement of both populations across management zones highlights the importance of understanding population dynamics to effective management of Lake Huron lake trout.

The Reality of Buffalo Breeding in Basra Governorate

Buffaloes in Iraq represent the most productive animal since its domestication in Mesopotamia about pre-historic era. Domestic water buffalo (Babalus Babalis) are common in the marshes of southern Iraq. On Sunday the UN cultural agency, UNESCO, added the marshlands and the ancient Sumerian cities that once flourished among them to its list of sites. The marshes today remain one of the poorest areas. Residents living on tiny floating islands fish, tend water buffalo and gather reeds. Little published research could be found into the numbers or environmental impacts of water buffalo in Basra governorate. One of the research objectives was to survey the water buffalo in this region including Al Dear, Al Hartha, Abu Alkhasib, Shat Alarab, Al Qurna, Al Mdainah, Imam Sadiq, Imam Qaim, Al Faw, Al Nshwa, Al Zubair and in Basra center. This study was conducted to evaluate all aspects of the river buffalo for the period from 2012-2016. Comprehensive knowledge of the breed characteristics, its population size and structure, taxonomy, geographical distribution and most important diseases is required to have effective management. As the marsh Arabs or Ma'adan complain of problems with some common buffalo diseases, such as those infecting the hoofs and the tongue, providing of veterinary services would be of critical value for buffalo breeding from an economical prospective.

Applications of vertebral morphometrics in Pacific Island archaeological fishing studies

AbstractSignificant differences between fish bone identification protocols in Pacific Island archaeology and other regions (e.g. Europe and North America) have influenced the use of vertebral morphometrics for the reconstruction of fish length and weight. Fish vertebral morphometrics using vertebrae identified to taxon and type (e.g. caudal, thoracic) are routinely reported in the archaeological literature outside of the Pacific Islands. Conversely, in Pacific Island archaeological fishing studies, vertebrae that are not identified to taxon have been utilised to assess change in average fish vertebrae size, and to reconstruct changes in fish length and weight over time. Using a fish bone assemblage from a prehistoric habitation site on Ebon Atoll, Republic of the Marshall Islands, we report false trends when vertebrae – not identified to taxon and type – are used to assess differences in average vertebrae size among cultural layers. These results are compared to the same assemblage where taxon and vertebra type are used to more accurately determine fish size. It is essential that vertebrae from Pacific Island fish bone assemblages are identified to taxon and type prior to assessing change in fish size over time, especially when investigating human impacts to finfish resources, capture technology or charting environmental change.

Assessment of Pollution in a Freshwater Lake at Fisher Island, Larsemann Hills over East Antarctica

Assessment of Pollution in a Freshwater Lake at Fisher Island, Larsemann Hills over East Antarctica