Chalk rivers: nature conservation and management

This is a handbook about Chalk Rivers Nature Conservation and Management from March 1999 by the Water Research Centre and commissioned by English Nature and the Environment Agency, primarly provides an objective basis for formulating conservation strategies for relevant Site of Special Scientific Interest (SSSIs) and Special Areas of Conservation (SACs). It was also seen as being applicable to chalk rivers more generally and has increasingly been regarded as important to the work of the Biodiversity Action Plan Steering Group on chalk rivers, which is led by the Environment Agency. This report contains information on characteristic wildlife communities, their habitat requirements and the ecological impact of activities that are relevant to the chalk river environment. It provides guidance on setting management objectives, options for mitigating impacts, and measures for the maintaining and enhancing the river channel, riparian and floodplain areas associated. The term `chalk river’ is used to describe watercourses dominated by groundwater discharge from chalk geology, including those that flow over a range of non-chalk surface geologies at various points along their length. England contains numerous examples of this river type, located in and downstream of areas of outcropping chalk in the south, East Anglia and up into Lincolnshire and Yorkshire. Indeed, England has the major part of the chalk river resource of Europe. A number of chalk rivers have been designated as Sites of Special Scientific Interest (SSSIs) and English Nature and Environment Agency work drawing up joint conservation strategies.

Avaliação vestibular em indivíduos com cinetose

A cinetose tem elevada prevalência mundial, sendo mais frequente na infância e no sexo feminino, mas também pode acometer adultos. Resulta de um conflito vestíbulo-visual que incide durante a locomoção em diversos meios de transporte, como carro, ônibus, avião e barco. A forma mais dramática ocorre no transporte marítimo. Ocasiona náusea, vômito, sudorese, aumento da salivação, redução do apetite, hipotensão e mal-estar. Geralmente é produzida por estímulo vestibular, mas também pode ser induzida por estímulo visual. Tanto as acelerações lineares quanto angulares geram cinetose se persistirem por longo período em indivíduos susceptíveis. Recentemente ocorre maior interesse nessa afecção devido ao crescente uso de tecnologia de simulação de vôo e direção automobilística. O objetivo do estudo foi analisar as alterações vestibulares nos indivíduos adultos com cinetose. Trata-se de um estudo prospectivo, tipo série de casos. Os pacientes do ambulatório do Hospital Universitário Pedro Ernesto-UERJ foram avaliados através de anamnese geral e dirigida e exame fisico geral e otorrinolaringológico. Aqueles com histórico de doença otológica foram excluídos. Posteriormente realizaram audiometria e testes vestibulares com o registro gráfico dos nistagmos através da vectoeletronistagmografia. Nos resultados das provas calóricas encontramos 3,33% de pacientes com alteração de predomínio direcional, 6,67% com alteração de predomínio labiríntico, 3,33% com hiperreflexia esquerda, 3,33% com hiporreflexia direita e 3,33% com hiporreflexia esquerda. Encontrados algumas variações na análise dos movimentos sacádicos, nistagmo optocinético e rastreio pendular. Os resultados foram de encontro aos achados da literatura. Diante dos achados, foi observado que o exame otoneurológico com registro gráfico da cinetose mostrou-se muito importante para a avaliação dos pacientes com essa afecção. O estudo traz benefícios por contribuir para o melhor entendimento da cinetose e estimular novas pesquisas na área.

Análise tribológica na interface aço carbono SAE 1020 e poliamida 11 em sistemas de deslizamento automotivos

Sistemas deslizantes com interface formada com aços baixa liga e polímeros variados são vastamente utilizados na indústria automotiva em sistemas de transmissão de torque submetidas à carregamento axial. Geralmente esses sistemas são acoplados aos sistemas de direção e interagem quase diretamente com o usuário final do veículo. Para conhecer as condições de desgaste mais severas as quais esses sistemas são submetidos e tentar minimiza-las, foi proposta a análise tribológica, em tribômetro do tipo pino-no-disco, da interface aço SAE 1020 com poliamida 11 em água destilada, solução aquosa com 5% em massa de cloreto de sódio e solução aquosa com 184,21 g/l. de areia natural, de acordo com as normas técnicas automotivas VW PV1210:2010-02 e VW PV2982:2013-07. Os ensaios foram realizados em frequências de 3,0 Hz e 1,5 Hz com quantidade fixada em 10.000 ciclos de rotação. O potencial de corrosão em circuito aberto foi monitorado ao longo dos ensaios e a taxa de desgaste foi calculada. Foram evidenciados maiores coeficientes de atrito, maiores taxas de desgaste e maiores amplitudes de potencial de corrosão nas amostras ensaiadas em solução de areia; com valores mais brandos para as amostras ensaiadas em água destilada e valores intermediários para as amostras ensaiadas em solução de cloreto de sódio.

Maryland commercial fisheries statistics, 1946-1950

This bulletin is the second of a series begun in 1948, designed to present detailed records of the commercial fish catch of the state. The statistics set forth were derived from records obtained only from licensed commercial fishermen and contain no data pertaining to small unlicensed units of fishing gear, or to the sports fishery.

Maryland commercial fisheries statistics, 1951-1952

This bulletin is the third of a series begun in 1948, presenting detailed data on the commercial fin-fishery of Maryland. A full description of the techniques of collection and tabulation were included in the first bulletin [Publication 69], and inasmuch as identical procedures have been employed throughout the program, further mention of methods is not made. As in past years, records were received on a voluntary basis from approximately 94% of all licensed fishermen. Most of the records were submitted in the form of weekly or monthly summaries. The statistics set forth were derived from records obtained only from licensed commercial fishermen and contain no data pertaining to small unlicensed units of fishing gear, or to the sport fishery.

Maryland commercial fisheries statistics, 1944-1945

This report presents a statistical analyses of the "fin" fisheries, as distinguished from the crab and oyster fisheries of Maryland, for 1944 and 1945. Comparative data on the catch by species, by area, and by gear, based principally on daily reports from the fishermen, are available for the first time as a result of a comprehensive statistical survey made by the Department of Research and Eduction to determine the results of the new management plan for the fisheries, referred to as the Maryland Management Plan. With the initiation in 1941 of a new system of fishery management in the State, a conservation plan based on the principle of stabilized fishing effort, it became obvious that a more accurate catch record system was needed for the proper administration of the program. The Management Plan stabilized the number of licensed fishermen at the 1939-1940 level, and provided for controlled expansion of the fishery to take place only when and where the industry warranted it as a result of increased fish populations. The text of the Plan may be found in Article 39, Section 60, Annotated Code of Maryland, 1943 Supplement. Publications 1, 2, 5, and 6 of the Educational Series of the Department of Research and Education explain the operating principles and the application of same to two important Maryland species, the shad and the rock or striped bass. Ocean fishery records only cover monthly gross landings.

The Maryland crab industry, 1950

This report contains the latest and most complete figures available on Maryland's crab industry for 1950. In it the amount and the value of crabs have been recorded on monthly, gear, and area bases.

Evaluation of the In Situ Ichthyoplankton Imaging System (ISIIS): comparison with the traditional (bongo net) sampler

Plankton and larval fish sampling programs often are limited by a balance between sampling frequency (for precision) and costs. Advancements in sampling techniques hold the potential to add considerable efficiency and, therefore, add sampling frequency to improve precision. We compare a newly developed plankton imaging system, In Situ Ichthyoplankton Imaging System (ISIIS), with a bongo sampler, which is a traditional plankton sampling gear developed in the 1960s. Comparative sampling was conducted along 2 transects ~30–40 km long. Over 2 days, we completed 36 ISIIS tow-yo undulations and 11 bongo oblique tows, each from the surface to within 10 m of the seafloor. Overall, the 2 gears detected comparable numbers of larval fishes, representing similar taxonomic compositions, although larvae captured with the bongo were capable of being identified to lower taxonomic levels, especially larvae in the small (<5 mm), preflexion stages. Size distributions of the sampled larval fishes differed considerably between these 2 sampling methods, with the size range and mean size of larval fishes larger with ISIIS than with the bongo sampler. The high frequency and fine spatial scale of ISIIS allow it to add considerable sampling precision (i.e., more vertical sections) to plankton surveys. Improvements in the ISIIS technology (including greater depth of field and image resolution) should also increase taxonomic resolution and decrease processing time. When coupled with appropriate net sampling (for the purpose of collecting and verifying the identification of biological samples), the use of ISIIS could improve overall survey design and simultaneously provide detailed, process-oriented information for fisheries scientists and oceanographers.

Quantification and reduction of unobserved mortality rates for snow, southern Tanner, and red king crabs (Chionoecetes opilio, C. bairdi, and Paralithodes camtschaticus) after encounters with trawls on the seafloor

Unobserved mortalities of nontarget species are among the most troubling and difficult issues associated with fishing, especially when those species are targeted by other fisheries. Of such concern are mortalities of crab species of the Bering Sea, which are exposed to bottom trawling from groundfish fisheries. Uncertainty in the management of these fisheries has been exacerbated by unknown mortality rates for crabs struck by trawls. In this study, the mortality rates for 3 species of commercially important crabs—red king crab, (Paralithodes camtschaticus), snow crab (Chionoecetes opilio) and southern Tanner crab (C. bairdi)—that encounter different components of bottom trawls were estimated through capture of crabs behind the bottom trawl and by evaluation of immediate and delayed mortalities. We used a reflex action mortality predictor to predict delayed mortalities. Estimated mortality rates varied by species and by the part of the trawl gear encountered. Red king crab were more vulnerable than snow or southern Tanner crabs. Crabs were more likely to die after encountering the footrope than the sweeps of the trawl, and higher death rates were noted for the side sections of the footrope than for the center footrope section. Mortality rates were ≤16%, except for red king crab that passed under the trawl wings (32%). Herding devices (sweeps) can expand greatly the area of seafloor from which flatfishes are captured, and they subject crabs in that additional area to lower (4–9%) mortality rates. Raising sweep cables off of the seafloor reduced red king crab mortality rates from 10% to 4%.

Influence of soak time and fish accumulation on catches of reef fishes in a multispecies trap survey

Catch rates from fishery-independent surveys often are assumed to vary in proportion to the actual abundance of a population, but this approach assumes that the catchability coefficient (q) is constant. When fish accumulate in a gear, the rate at which the gear catches fish can decline, and, as a result, catch asymptotes and q declines with longer fishing times. We used data from long-term trap surveys (1990–2011) in the southeastern U.S. Atlantic to determine whether traps saturated for 8 reef fish species because of the amount of time traps soaked or the level of fish accumulation (the total number of individuals of all fish species caught in a trap). We used a delta-generalized-additive model to relate the catch of each species to a variety of predictor variables to determine how catch was influenced by soak time and fish accumulation after accounting for variability in catch due to the other predictor variables in the model. We found evidence of trap saturation for all 8 reef fish species examined. Traps became saturated for most species across the range of soak times examined, but trap saturation occurred for 3 fish species because of fish accumulation levels in the trap. Our results indicate that, to infer relative abundance levels from catch data, future studies should standardize catch or catch rates with nonlinear regression models that incorporate soak time, fish accumulation, and any other predictor variable that may ultimately influence catch. Determination of the exact mechanisms that cause trap saturation is a critical need for accurate stock assessment, and our results indicate that these mechanisms may vary considerably among species.

Strandings as indicators of marine mammal biodiversity and human interactions off the coast of North Carolina

The adjacency of 2 marine biogeographic regions off Cape Hatteras, North Carolina (NC), and the proximity of the Gulf Stream result in a high biodiversity of species from northern and southern provinces and from coastal and pelagic habitats. We examined spatiotemporal patterns of marine mammal strandings and evidence of human interaction for these strandings along NC shorelines and evaluated whether the spatiotemporal patterns and species diversity of the stranded animals reflected published records of populations in NC waters. During the period of 1997–2008, 1847 stranded animals were documented from 1777 reported events. These animals represented 9 families and 34 species that ranged from tropical delphinids to pagophilic seals. This biodiversity is higher than levels observed in other regions. Most strandings were of coastal bottlenose dolphins (Tursiops truncatus) (56%), harbor porpoises (Phocoena phocoena) (14%), and harbor seals (Phoca vitulina) (4%). Overall, strandings of northern species peaked in spring. Bottlenose dolphin strandings peaked in spring and fall. Almost half of the strandings, including southern delphinids, occurred north of Cape Hatteras, on only 30% of NC’s coastline. Most stranded animals that were positive for human interaction showed evidence of having been entangled in fishing gear, particularly bottlenose dolphins, harbor porpoises, short-finned pilot whales (Globicephala macrorhynchus), harbor seals, and humpback whales (Megaptera novaeangliae). Spatiotemporal patterns of bottlenose dolphin strandings were similar to ocean gillnet fishing effort. Biodiversity of the animals stranded on the beaches reflected biodiversity in the waters off NC, albeit not always proportional to the relative abundance of species (e.g., Kogia species). Changes in the spatiotemporal patterns of strandings can serve as indicators of underlying changes due to anthropogenic or naturally occurring events in the source populations.

Estimating overall fish bycatch in U.S. commercial fisheries

Bycatch, or the unintended capture of fish, marine mammals, sea turtles, and seabirds by fishing gear, occurs to some degree in most fisheries. The recently released National Marine Fisheries Service’s (NMFS) U.S. National Bycatch Report provides information on bycatch in U.S. commercial fisheries by fishery and species. The report also provides national statistics in the form of national bycatch ratio and a national bycatch estimate. We describe the methods used to develop these statistics and compare them to similar studies. We conclude that the national bycatch ratio and national bycatch estimates developed by NMFS represent the best available information on bycatch in U.S. fisheries. However, given changes in bycatch management over time, as well as inter-annual variability in bycatch levels and a high percentage of fisheries for which data on bycatch are not currently available, we recommend that NMFS continue to support bycatch data collection and reporting efforts to improve the quality and quantity of bycatch data and estimates available to fisheries managers and scientists over time. This will enable NMFS to meet its requirements for bycatch reporting under the Magnuson-Stevens Act (MSA), as well as requirements for bycatch minimization under the MSA, Marine Mammal Protection Act, and Endangered Species Act.

Characterization of the U.S. Gulf of Mexico and South Atlantic penaeid and rock shrimp fisheries based on observer data

In July 2007, a mandatory Federal observer program was implemented to characterize the U.S. Gulf of Mexico penaeid shrimp (Farfantepenaeus aztecus, F. duorarum, and Litopenaeus setiferus) fishery. In June 2008, the program expanded to include the South Atlantic penaeid and rock shrimp, Sicyonia spp., fisheries. Data collected from 10,206 tows during 5,197 sea days of observations were analyzed by geographical area and target species. The majority of tows (~70%) sampled were off the coasts of Texas and Louisiana. Based on total hours towed, the highest concentrated effort occurred off South Texas and southwestern Florida. Gear information, such as net characteristics, bycatch reduction devices, and turtle excluder devices were fairly consistent among areas and target species. By species categories, finfish comprised the majority (≥57%) of the catch composition in the Gulf of Mexico and South Atlantic penaeid shrimp fisheries, while in the South Atlantic rock shrimp fishery the largest component (41%) was rock shrimp. Bycatch to shrimp ratios were lower than reported in previous studies for the Gulf of Mexico penaeid shrimp fishery. These decreased ratios may be attributed to several factors, notably decreased shrimp effort and higher shrimp catch per unit of effort (CPUE) in recent years. CPUE density surface plots for several species of interest illustrated spatial differences in distribution. Hot Spot Analyses for shrimp (penaeid and rock) and bycatch species identified areas with significant clustering of high or low CPUE values. Spatial and temporal distribution of protected species interactions were documented.

A guide to the deep-water sponges of the Aleutian Island Archipelago

The first dedicated collections of deep-water (>80 m) sponges from the central Aleutian Islands revealed a rich fauna including 28 novel species and geographical range extensions for 53 others. Based on these collections and the published literature, we now confirm the presence of 125 species (or subspecies)of deep-water sponges in the Aleutian Islands. Clearly the deep-water sponge fauna of the Aleutian Islands is extraordinarily rich and largely understudied. Submersible observations revealed that sponges, rather than deep-water corals, are the dominant feature shaping benthic habitats in the region and that they provide important refuge habitat for many species of fish and invertebrates including juvenile rockfish (Sebastes spp.) and king crabs (Lithodes sp). Examination of video footage collected along 127 km of the seafloor further indicate that there are likely hundreds of species still uncollected from the region, and many unknown to science. Furthermore, sponges are extremely fragile and easily damaged by contact with fishing gear. High rates of fishery bycatch clearly indicate a strong interaction between existing fisheries and sponge habitat. Bycatch in fisheries and fisheries-independent surveys can be a major source of information on the location of the sponge fauna, but current monitoring programs are greatly hampered by the inability of deck personnel to identify bycatch. This guide contains detailed species descriptions for 112 sponges collected in Alaska, principally in the central Aleutian Islands. It addresses bycatch identification challenges by providing fisheries observers and scientists with the information necessary to adequately identify sponge fauna. Using that identification data, areas of high abundance can be mapped and the locations of indicator species of vulnerable marine ecosystems can be determined. The guide is also designed for use by scientists making observations of the fauna in situ with submersibles, including remotely operated vehicles and autonomous underwater vehicles.

A pilot survey of deepwater coral/sponge assemblages and their susceptibility to fishing/harvest impacts at the Olympic Coast National Marine Sanctuary (OCNMS). Cruise report for NOAA Ship McARTHUR II Cruise AR-04-04: Leg 2 (June 1-12, 2004)

The offshore shelf and canyon habitats of the OCNMS are areas of high primary productivity and biodiversity that support extensive groundfish fisheries. Recent acoustic surveys conducted in these waters have indicated the presence of hard-bottom substrates believed to harbor unique deep-sea coral and sponge assemblages. Such fauna are often associated with shallow tropical waters, however an increasing number of studies around the world have recorded them in deeper, cold-water habitats in both northern and southern latitudes. These habitats are of tremendous value as sites of recruitment for commercially important fishes. Yet, ironically, studies have shown how the gear used in offshore demersal fishing, as well as other commercial operations on the seafloor, can cause severe physical disturbances to resident benthic fauna. Due to their exposed structure, slow growth and recruitment rates, and long life spans, deep-sea corals and sponges may be especially vulnerable to such disturbances, requiring very long periods to recover. Potential effects of fishing and other commercial operations in such critical habitats, and the need to define appropriate strategies for the protection of these resources, have been identified as a high-priority management issue for the sanctuary.