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Showing 1 to 17 of 17 for “"fisheries ecology"”.
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Fish scales as ecological indicators: empirical approaches to improve their practical application to fish ecology
… research and monitoring programmes in freshwater fisheries. Although used primarily to age individual fish, there is increasing evidence of their potential for application to other ecological methods, yet there is also considerable uncertainty in how this can be achieved. Thus, the purpose of this …
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An Approach For Use of Dual Frequency Identification Sonar (DIDSON) to Quantify Behavioral Aspects of Piscivory at Ecologically Relevant Time and Space Scales
<p>Predator-prey interactions of large vagile fishes are difficult to study in the ocean due to limitations in the space and time requirements for observations. Small-scale direct underwater observations by divers (<10m >radius) and large-scale hydroacoustic surveys (10s - 100s km2) are traditional …
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Growth and Yield-Per-Recruit Modeling of Spot (<i>Leiostomus xanthurus</i>) in the Chesapeake Bay, and a Comparison of Biological Reference Points
<p>Spot were sampled from the Chesapeake Bay commercial fishery from 1993–1995 to determine if spot are overfished. Transversely sectioned otoliths were determined to be the most appropriate structure for ageing spot. It was determined that spot have a high natural mortality rate (M = 0.9) and fast …
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TROPHIC ECOLOGY OF JUVENILE LEAN AND SISCOWET LAKE TROUT (SALVELINUS NAMAYCHUSH) FROM U.S. WATERS OF LAKE SUPERIOR
<p>In this study, I investigated the spatial overlap, diet similarity, and isotopic niches of juvenile Lean and Siscowet Lake Trout ecotypes across six ecoregions of Lake Superior. Spatially, Lean and Siscowet were observed in overlapping depth distributions. Leans were most abundant in shallow …
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Environment-induced Phenotypic Plasticity in the Teeth of Hatchery and Wild Largemouth Bass, <i>Micropterus floridanus</i>
Successful stock enhancement of hatchery-reared fish depends heavily on the release of individuals able to demonstrate strong survival skills. Overall survival of fishes is a reflection of a successful blend of physiology, anatomy, and behavior. With fishes being highly phenotypically plastic, the …
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Recruitment of Blue Crab, <i>Callinectes sapidus,</i> Postlarvae to the Back-Barrier Lagoons of Virginia's Eastern Shore
<p>Most research on the early life history of the blue crab, Callinectes sapidus, has been conducted in large partially stratified estuaries such as the Chesapeake Bay. In contrast, little is known about the recruitment dynamics or habitat requirements of blue crab postlarvae (megalopae) in shallow …
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In Support of a Rationally Managed Fishery: Age and Growth in Patagonian Toothfish (<i>Dissostichus eleginoides</i>)
… Ocean. Stock structure, critical to good fisheries management, can be inferred from growth differences between areas, but available growth data are compromised by inconsistencies in age estimation methods, sampling and sample sizes, and techniques used to derive estimates. I asked the …
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Assessing Freshwater Mussels (Bivalvia: Unionidae) in South Dakota and Identifying Drivers of Assemblage Variation
<p>Native freshwater mussels (Family: Unionidae) are among the most threatened groups of freshwater fauna on Earth. Approximately 35 species have gone extinct since the 1900s and 72% of remaining species are considered endangered, threatened, or species of special concern. Unionid research can …
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Molecular Phylogenetics of Perciform Fishes Using the Nuclear Recombination Activating Gene 1
<p>The order Perciformes contains one-third of all extant fishes in twenty different suborders and over 10,000 species. Few systematic investigations have been performed on this large group of fishes at the suborder level and their evolutionary history is widely recognized as problematic. This …
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Evaluation of Fish Scale Chemistry for Determining Habitat Associations
<p>This is the first work examining the utility of scale chemistry for determining natal origins and habitat associations. I quantified a relationship of scale chemistry to water chemistry, quantified geographic variation in scale chemistry, and evaluated stability of scale chemistry through …
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The Impact of Multiple Nursery Areas on the Population Structure of Atlantic Menhaden, <i>Brevooria tyrannus</i>
… marine food web and supports one of the largest fisheries on the US East Coast. In addition to a decrease in overall numbers and spawning stock biomass, recruitment levels have remained low since the 1990s. Menhaden use numerous estuaries along the Atlantic coast for juvenile development before …
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The Effect of "Casitas" on Lobster Biology and Fishery Sustainability in the Bahamas
<p>“Casitas” (artificial table-like structures) are a commercial fishing gear used to harvest Caribbean spiny lobster (<em>Panulirus argus</em>) in the Caribbean and in The Bahamas, where lobster is the most valuable fishery. Yet, casitas are largely unregulated in The Bahamas and they may threaten …
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The Importance of Keeping the Big Ones: Harvest Slot Limits and Marine Protected Areas for the Management of the Caribbean Spiny Lobster
… stability and reproductive success. Traditional fisheries management tools fail to protect these oldest and/or largest individuals, but two less conventional tools: marine protected areas (MPAs), and harvest slot limits have the potential to do so. Here I tested the possible use of these tools …
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Fishery Interaction Modeling of Cetacean Bycatch in the California Drift Gillnet Fishery to Inform a Dynamic Ocean Management Tool
… approach is determining the factors that lead to fisheries interactions. Using 25 years (1990-2014) of National Oceanic and Atmospheric Administration fisheries’ observer data from the California drift gillnet fishery, we model the relative probability of bycatch (presence–absence) of four …
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The impact of cormorants (Phalacrocorax carbo carbo and Phalacrocorax carbo sinensis) on inland fisheries in the UK
… presence of cormorants, feeding daily on their fisheries, has a damaging impact on fish stocks with inevitable financial losses. Due to a lack of effective non-lethal control methods, the angling bodies wish to see the cormorants removed from the protected species list so their inland numbers …
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The fish and fishery of Stocks Reservoir, Lancashire
… of English and Welsh stillwater trout fisheries, Stocks Reservoir was judged to rate poorly, returning the lowest performance data in the upland stocked category.An examination of the stomach and hind gut contents of 127 rainbow trout, 7 brook trout and 8 brown trout caught by anglers, …