Sport Fisheries Research Articles

Ortholinea concentrica n. sp. (Cnidaria: Myxozoa) from the Patagonian seabass Acanthistius patachonicus (Jenyns, 1840) (Perciformes: Serranidae) off Patagonia, Argentina.

The Patagonian seabass Acanthistius patachonicus (Jenyns, 1840) (Serranidae) is a marine fish valued for commercial and sport fisheries from Argentina. We report a new myxosporean (Cnidaria: Myxozoa) infecting the urinary system of the Patagonian seabass from San Antonio Bay, San Matías Gulf, on the Atlantic Ocean. The mature myxospores were subspherical, 8.2-11.0μm × 7.9-11.0μm and 7.7-9.0μm in thickness; two subspherical polar capsules, 2.4-3.8μm × 2.3-3.6μm, with 3 to 4 turns of the polar tubule; openings on different valves in almost opposite directions. Ornamented shell valves exhibited 17-20 concentrically organized surface ridges. SSU rDNA phylogenetics analyses placed the new species in the freshwater urinary tract clade, clustering in a clade formed by Myxobilatus gasterostei (Parisi, 1912), Acauda hoffmani Whipps, 2011, and other Ortholinea spp. Based on spore morphology, site of infection, and molecular data, we described this myxozoan as Ortholinea concentrica n. sp.

A baseline analysis of coastal water quality of the port Honduras marine reserve, Belize: a critical habitat for sport fisheries

This analysis examines temporal changes in water quality of the Port Honduras Marine Reserve (PHMR), Belize from 1998 to 2015. Trends in dissolved oxygen (DO), salinity, temperature and pH were analyzed from ten sites throughout PHMR for statistically significant relationships. Maintaining satisfactory water quality is critical for sustaining healthy fisheries. PHMR represents a unique link between upland watersheds and coastal wetlands, mangroves, coral reefs, and seagrass beds. These ecosystems comprise important habitat for many fisheries including the economically valuable sport fish species of Megalops atlanticus (Atlantic tarpon), Albula vulpes (bonefish) and Trachinotus falcatus (permit). Sport fishing in the PHMR area has become increasingly popular in recent decades and is responsible for generating direct and indirect income opportunities for local communities, including Punta Gorda, the largest town in southern Belize. As a result, degradation of water quality of PHMR through land-based human activities could have ecological and economic consequences for southern Belize. The results of the analyses revealed significant seasonal variations and slight increasing trends in DO and salinity at several sampling sites. These relatively stable results are likely related to several factors including limited coastal development and low population density of southern Belize. This study provides baseline information for future research and outlines recommendations for management strategies of PHMR to mitigate impacts from current and future threats to water quality.

Characterizing activity and assessing bycatch survival of Pacific halibut with accelerometer Pop-up Satellite Archival Tags

BackgroundPacific halibut support high-value commercial and sport fisheries in the north Pacific Ocean, making survival of Pacific halibut bycatch in trawl fisheries an important management concern. We present a method for characterizing activity and inferring survival of Pacific halibut based on accelerometer data from Pop-up Satellite Archival Tags (PSATs). A PSAT attached to a fish with a dart and tether floats freely above the fish in a vertical orientation when the fish is stationary, but switches to a more horizontal orientation when towed behind an active fish. We hypothesized that characteristic changes in PSAT orientation associated with activity could be detected by accelerometers and summarized for transmission by PSATs to provide valuable information on fish activity.ResultsWe developed procedures for inferring survival of Pacific halibut with accelerometer PSATs based on a progression of analysis steps that linked PSAT orientation, PSAT acceleration data, and Pacific halibut activity patterns. Relationships between PSAT orientation and Pacific halibut activity were confirmed by observations of PSAT orientation on Pacific halibut swimming in the laboratory and comparisons with depth data from tags on free-ranging Pacific halibut. We developed two metrics summarizing 1 Hz acceleration data for transmission to the Argos satellite network. The “knockdown” metric records abrupt changes in vertical acceleration, indicating both initiation of swimming bouts and sustained swimming behavior, and is robust to the effects of tidal currents. The “%tilt” metric records the amount of time the tag tilts past a vertical orientation threshold and captures the proportion of each time bin that the fish is active. These PSAT metrics revealed diel behavior and three activity modes present in free-ranging Pacific halibut that allowed inference of survival when compared to PSAT data from fish carcasses and weighted tags.ConclusionsAccelerometer PSAT metrics developed in this study revealed Pacific halibut activity patterns, and thus survival, and may be extended to other fish species. Economical accelerometer PSATs can allow larger sample sizes that enhance bycatch survival studies while detecting fish activity in flat study areas. PSAT advantages over other survival estimation methods include providing outcomes for all specimens during exposure to natural conditions.

Non-lethal aging of tropical catch-and-release sport fishery species

Non-lethal methods for deriving age estimates from species of conservation significance or those supporting catch-and-release sport fisheries can assist in their sustainable management. In this study we tested if dorsal spines provide equivalent age estimates to otoliths for two species of large tropical snappers (Lutjanus goldiei and L. fuscescens, Lutjanidae) that support a catch-and-release sport fishery in remote parts of Papua New Guinea. Comparison of putative age estimates from sections taken at the base, mid and tip of the dorsal spine revealed that the base sections provided the most similar ages to otoliths, while mid and tip sections underestimated otolith age, especially for older individuals. Dorsal spine base-sections provided equivalent age estimates to otoliths for both species across the full range of ages examined (up to 17 for L. goldiei, and 14 for L. fuscescens). Like other lutjanids, these species show a wide range in length-at-age. This means that small fish are not necessarily young fish, and recruitment could potentially fail for more than a decade before anglers or guides notice a lack of smaller fish in their captures, by which time the opportunity to identify and reverse the cause of recruitment failure may have passed. Dorsal spines provide an effective and minimally-harmful means of monitoring population age structure to ensure ongoing recruitment to the fishery, and offer the opportunity for engagement of anglers, guides, and community members in the sustainable management of this fishery.

Inland fish stock assessment: Applying data‐poor methods from marine systems

AbstractInland fisheries can be diverse, local and highly seasonal. This complexity creates challenges for monitoring, and consequently, many inland fish stocks have few data and cannot be assessed using methods typically applied to industrial marine fisheries. In such situations, there may be a role for methods recently developed for assessment of data‐poor fish stocks. Herein, three established data‐poor assessment tools from marine systems are demonstrated to highlight their value to inland fisheries management. A case study application uses archived length, catch and catch‐per‐unit‐effort data to characterise the ecological status of an important recreational brown trout stock in an Irish lake. This case study is of specific use to management of freshwater sport fisheries, but the broader purpose of the paper was to provide a crossover between marine and inland fisheries science, and to highlight accessible data‐poor assessment approaches that may be applicable in diverse inland systems.

Future scope of sport fisheries development in India: A review

Future scope of sport fisheries development in India: A review

Protecting Offshore Areas from Oil and Gas Leasing: Presidential Authority under the Outer Continental Shelf Lands Act and the Antiquities Act

For over one hundred years, Presidents of both parties have used executive power to protect America’s lands and waters. Until the second half of the twentieth century, however, little attention was given to protecting the marine ecosystem. Federal authority reaches out to two hundred miles or more in the oceans off the United States, covering an area known as the Outer Continental Shelf. Federal interest in the area historically focused on developing oil and gas reserves and ensuring that the area was open to trade and commerce. The area is also very important for indigenous subsistence uses and commercial and sport fisheries. Yet it has received scant attention from Congress in terms of environmental protection. Climate change and ocean acidification have increased recognition of the marine ecosystem’s importance to the overall health of the planet. This Article reviews President Obama’s recent withdrawal of swaths of the outer continental shelf from oil and gas leasing under the Outer Continental Shelf Lands Act. It argues that while Congress has paramount authority over the outer continental shelf and retains the authority to undo conservation actions, it has delegated limited conservation authority to the President under section 12(a) of the act. Thus, President Obama’s recent protective measures taken under the act may only be altered by Congress—not by a subsequent President. This Article compares the President’s withdrawal authority under the Outer Continental Shelf Lands Act to the President’s authority to establish national monuments under the Antiquities Act. It argues that Congress did not delegate power to revoke national monument designations under the Antiquities Act, nor permanent withdrawals under Section 12(a) of the Outer Continental Shelf Lands Act.

Modeling the Responses of Alligator Gar Populations to Harvest under Various Length‐Based Regulations: Implications for Conservation and Management

AbstractInterest in managing Alligator Gar Atractosteus spatula populations as a unique sport fishery has increased over the past decade, but despite this interest population responses to harvest are poorly understood. Fishing regulations for Alligator Gars vary throughout their distribution; however, to date most regulations have focused on a daily creel limit. We developed an age‐structured dynamic‐pool model in R to (1) quantify the population‐level effects of exploitation and (2) evaluate how these effects would be altered under a suite of length‐based fishing regulations. The model was parameterized based primarily on empirically estimated dynamic rates for Texas Alligator Gar populations. For each model scenario, we calculated the mean and variance of the number of trophy fish in the population, the population size, the spawning potential ratio, and the fishery yield over a 100‐year period. Alligator Gar populations were highly sensitive to exploitation in our model simulations. An exploitation rate of 7% caused the average population size to decline by 50%, and a rate of only 3% halved the number of trophy fish available in the population. Under no length restrictions, recruitment overfishing occurred above an exploitation rate of 6.5%, while yield was maximized at only 9% exploitation. Based on our model results, the use of length limits may provide some options for sustaining existing trophy Alligator Gar fisheries under increased effort and could allow anglers to catch and even harvest more trophy‐size fish. Given the sensitivity of long‐lived periodic life history strategists to exploitation and the benefits that length‐based regulations can provide, we encourage managers to consider such regulations to increase resilience to exploitation and improve fishery quality.

Quantitative Evaluation of Paddlefish Sport Fisheries in Missouri's Large Reservoirs: Implications for the Management of Trophy Sport Fisheries

AbstractLake of the Ozarks, Harry S. Truman Reservoir, and Table Rock Lake in Missouri contain important recreational fisheries for trophy Paddlefish Polyodon spathula. These three reservoirs were created by damming major rivers. Because of river modifications, Paddlefish natural reproduction is thought to be limited; subsequently, populations have been maintained through supplementation and harvest regulations. However, these fisheries have not been thoroughly assessed, and the applicability of management actions (e.g., supplementation and minimum length limits) has not been fully evaluated. Population simulations indicated that changes in the amount of trophy‐sized Paddlefish and broodstock remaining were similar among the three reservoirs, with larger minimum length limits resulting in a greater proportion of mature and trophy‐sized individuals. However, the number of Paddlefish that could be harvested at Harry S. Truman Reservoir and Lake of the Ozarks was much greater than at Table Rock Lake. These disparities are likely attributable to the amount of supplementation occurring at each reservoir. Based on unmarked fish from each reservoir, the percentage of sampled fish that were considered wild suggested that natural reproduction is occurring in Lake of the Ozarks (51.5%), Harry S. Truman Reservoir (83.9%), and Table Rock Lake (13.7%). Considering the Missouri Department of Conservation's desired management goals for maintaining trophy fisheries, a minimum length limit of at least 864 mm is suggested. If supplementation, natural reproduction, and harvest regulations are inadequate, reductions in Paddlefish abundance, size structure, harvest, and popularity could occur. One motivator for anglers to participate in trophy fisheries is the opportunity to catch a rare, unique, and large fish. Declines in a trophy fishery could cause economic losses to local areas and state agencies; thus, having an adaptive management plan in place to manage trophy fisheries is imperative.

Under‐Ice Population Density Estimation of Alaska Blackfish

AbstractThe Alaska Blackfish Dallia pectoralis is an understudied but ecologically important mudminnow occurring in lentic ecosystems of subarctic and Arctic Alaska. We sampled a population of Alaska Blackfish during the winter months in an upland pond near Fairbanks, Alaska, and we used a simple mark–recapture estimator to provide the first population estimate for this species. We found that Alaska Blackfish density in the pond was approximately 0.27 individuals/m2, equating to an estimated biomass of 15 g/m2 of pond surface area, which is similar to density estimates reported for other mudminnow species. We tested capture methods and found that under‐ice minnow trapping was a poor method during early winter (September–December) but was highly effective near methane sumps and areas of high muskrat Ondatra zibethicus activity in late winter (March–April). Qualitatively, nearshore minnow trapping, seining, and kicknetting during the ice‐free season were less effective than under‐ice trapping. Cursorily, pelvic fin clips were more effective for batch marking of Alaska Blackfish than two types of subcutaneous tags, given the high numbers of individuals we captured and the species’ relatively small body size and dark skin, which hindered tag visualization. We demonstrated that Alaska Blackfish can occur at high densities in their typical habitat, underscoring their importance as forage fish in Alaskan freshwater ecosystems that support subsistence and sport fisheries for piscivorous fishes. Extending this approach across the geographic range of Alaska Blackfish will improve understanding of the ecological role of this species in the varying aquatic ecosystems where it occurs.

Freshwater fishes of Orissa, India

Varied freshwater resources of Orissa blessed with diverse fish fauna. In total, 186 species of fishes belonging to 11 orders, 33 families and 96 genera were recorded from various freshwater bodies of Orissa. Cypriniformes was the most dominant order and Cyprinidae was diverse family. The trophic level of fishes of Orissa ranged from 2.0 to 4.5 containing 62.41% of carnivorous species. Fishery status revealed existence of 120 species worth for capture fishery, 101 species worth for ornamental fishery, 37 species worth for culture fishery and 25 species worth for sport fishery. Threat status comprises of one Critically Endangered species, five Endangered species, three Vulnerable species and remaining 177 species were Not Threatened. The findings of present communication may serve as baseline information for planning, conservation and management of fish and fisheries resources of Orissa.

Freshwater fishes of Orissa, India

Varied freshwater resources of Orissa blessed with diverse fish fauna. In total, 186 species of fishes belonging to 11 orders, 33 families and 96 genera were recorded from various freshwater bodies of Orissa. Cypriniformes was the most dominant order and Cyprinidae was diverse family. The trophic level of fishes of Orissa ranged from 2.0 to 4.5 containing 62.41% of carnivorous species. Fishery status revealed existence of 120 species worth for capture fishery, 101 species worth for ornamental fishery, 37 species worth for culture fishery and 25 species worth for sport fishery. Threat status comprises of one Critically Endangered species, five Endangered species, three Vulnerable species and remaining 177 species were Not Threatened. The findings of present communication may serve as baseline information for planning, conservation and management of fish and fisheries resources of Orissa.

First molecular data for Lernaea cyprinacea (Copepoda: Cyclopoida) infesting Odontesthes bonariensis, a commercially important freshwater fish in Argentina.

Parasitic copepods of the family Lernaeidae are often found infesting freshwater fishes worldwide. They cause lernaeosis, a disease that can lead to serious pathogenic effects on their fish hosts. The most common lernaeid is the Lernaea cyprinacea, which has been widely introduced through importation of tropical fishes, e.g. cyprinids. In South America, it is one of the most common parasites both in wild and in farmed fish in the central region of Argentina. The silverside Odontesthes bonariensis is the most important fish of the sport fisheries of Argentina and one of the fish most affected by lernaeosis. Six specimens of copepods were collected from 30 specimens of O. bonariensis collected in a Pampean shallow lake (33°25'28"S 62°53'56"W) of Córdoba (Argentina). The 28S rRNA gene of L. cyprinacea was amplified by means of PCR to obtain the 28S rDNA sequence. The sequence obtained of this parasite from Argentina showed high genetic similarity with those from various geographical origins. The present study provided molecular characterization of L. cyprinacea in South America for the first time.

Identifying cost-effective invasive species control to enhance endangered species populations in the Grand Canyon, USA

Recovering endangered species populations when confronted with the threat of invasive species is an ongoing natural resource management challenge. While eradication of the invasive species is often the optimal economic solution, it may not be a feasible nor desirable management action in other cases. For example, when invasive species are desired in one area, but disperse into areas managed for endangered species, managers may be interested in persistent, but cost-effective means of managing dispersers rather than eradicating the source. In the Colorado River, a nonnative rainbow trout (Oncorhynchus mykiss) sport fishery is desired within Glen Canyon National Recreation Area, however, dispersal downriver into the Grand Canyon National Park is not desired as rainbow trout negatively affect endangered humpback chub (Gila cypha). Here, we developed a bioeconomic model incorporating population abundance goals and cost-effectiveness analyses to approximate the optimal control strategies for invasive rainbow trout conditional on achieving endangered humpback chub adult population abundance goals. Model results indicated that the most cost-effective approach to achieve target adult humpback chub abundance was a high level of rainbow trout control over moderately high rainbow trout population abundance. Adult humpback chub abundance goals were achieved at relatively low rainbow trout abundance and control measures were not cost-effective at relatively high rainbow trout abundance. Our model considered population level dynamics, species interaction and economic costs in a multi-objective decision framework to provide a preferred solution to long-run management of invasive and native species.

Pattern of reproductive biology of the endangered golden mahseer Tor putitora (Hamilton 1822) with special reference to regional climate change implications on breeding phenology from lesser Himalayan region, India

ABSTRACTMahseer is an important group of endemic game fish found in the Indian subcontinent inhabiting in streams, riverine pools and lakes. Besides commercial fishery, it also forms lucrative sport fishery in the Himalayan rivers. Samples of golden mahseer (Tor putitora) were collected from the river Kosi at Ramnagar area (lesser Himalayan region) of Uttarakhand, India during 2014–2016 to study reproductive biology and trace any changes in breeding phenology from earlier records. The observed breeding season was from July till September. In males (310–565 mm, 355–1750 g) and females (315–580 mm, 260–2500 g), GSI values surged from late June to early July and peaked in August. Absolute and relative fecundity ranged from 4217 to 8365 and from 3667 to 7348 per kg, respectively. The maximum water temperature was usually recorded in May (30.5°C) and minimum (18.4°C) in January. Sex ratio was estimated at 1:1.25 with χ2 value of 3.20 and the difference was non-significant. The breeding phenology of golden mahseer may likely have gone through two distinct steps of transformation viz. shifting-prolongation (1911–1981) and reduction-stabilization (1981–present). Even after a probable reduction in duration of breeding season and shift (delay) in onset of breeding in Golden mahseer population of lesser Himalayan region during 1911–1981, some stabilization in breeding phenology appears to have been attained since 2000s. It is predicted that the species appears to be continuously adapting to changing climate in lesser Himalayas.

Quantitative Evaluation of Paddlefish Sport Fisheries in Missouri’s Large Reservoirs: Implications for the Management of Trophy Sport Fisheries

AbstractLake of the Ozarks, Harry S. Truman Reservoir, and Table Rock Lake in Missouri contain important recreational trophy Paddlefish fisheries. These three reservoirs have been created by damming major rivers. Because of river modifications, Paddlefish natural reproduction is thought to be limited, and subsequently, populations have been maintained through supplementation and harvest regulations. However, these fisheries have not been thoroughly assessed and the applicability of management actions (e.g., supplementation and minimum length limits) has not been fully evaluated. Population simulations indicated changes in the amount of trophy sized fish and broodstock remaining of each population were similar, with larger minimum length limits resulting in a greater proportion of mature and trophy sized individuals. However, the number of Paddlefish that could be harvested at Harry S. Truman Reservoir and Lake of the Ozarks was much greater than at Table Rock Lake. These disparities are likely attributed ...

Double‐Crested Cormorants: Too Much of a Good Thing?

For centuries, people have viewed double‐crested cormorantsPhalacrocorax auritusnegatively, and human persecution coupled with environmental contamination severely reduced numbers of cormorants throughout North America. Shifts in paradigms for management of our natural resources resulted in reductions in environmental contaminants and regulatory protection of cormorants, allowing for an amazing population resurgence of this adaptable fish‐eating bird. However, for cormorants, as with some other native wildlife species the populations of which have rebounded due to conservation efforts, there have been cormorant‐societal conflicts with respect to commercial and natural resources such as aquaculture and sport fisheries. Increasing resource conflicts caused cormorants to be a priority with agencies responsible for their management, resulting in development of policy to facilitate addressing stakeholder concerns. Subsequent research and management in regard to cormorant issues have been subject to considerable challenges and debate. In this feature, we discuss the primary resource damage issues associated with cormorants, management efforts and outcomes, what we have learned, and the future with regard to cormorant management.

Homing of Pacific Salmon to a Marine Release Site: A Case Study of the Homer Spit Fishing Hole, Alaska

Fishery enhancement projects can provide unanticipated research opportunities to reveal fundamental aspects of the biology of species being produced. Although Pacific salmon are well known for their abilities to migrate home to freshwaters for spawning, homing to marine release sites is not widely known or understood. For more than three decades, juvenile Chinook salmon (Oncorhynchus tshawytscha) and coho salmon (O. kisutch) have been released into and subsequently homed back as adults to a nondescript semi-natural saltwater lagoon in Homer, Alaska, supporting a popular sport fishery. Through a case study of the fishery enhancement project at the “Homer Spit Fishing Hole”, also known as the Nick Dudiak Fishing Lagoon (NDFL), we illustrate a rare example of homing to marine release sites by Pacific salmon. Our goals are to briefly review the history of the NDFL sport fishery and provide evidence of homing through patterns of release, angler harvest, and coded-wire tag recoveries. We discuss the potential for olfactory imprinting to marine-derived environmental cues in conjunction with geomagnetic imprinting and navigation that may be underpinning the ability for adult salmon to home to this marine release site. Although the proximate factors that allow homing to the NDFL remain unclear, we suggest that this peculiar fishery represents a serendipitous opportunity to explore patterns of migration, imprinting, and homing by Pacific salmon.

Angling‐Induced Impacts on Recruitment and Contributions to Reproduction in Florida Bass

AbstractBlack basses Micropterus spp. are the focus of extensive management efforts throughout North America, where they support a multibillion‐dollar recreational sport fishery. Harvest rates in many bass fisheries have declined in recent decades, yet a growing number of studies have proposed that catch‐and‐release angling practices, such as bed‐fishing in which anglers intentionally target bass while the fish are defending their nests, can decrease individual reproductive success. In response, management agencies have restricted fishing during the spawning period in some regions. We evaluated the impacts of catch‐and‐release bed‐fishing on Florida Bass M. salmoides floridanus nest success, reproductive success, production of fall recruits, and the number of parents that contributed to reproduction. Eighteen replicate populations simulating natural Florida lakes were established, and ponds were assigned either a bed‐fishing (n = 10) or a control treatment (n = 8). Snorkel surveys were conducted throughout the spawning period to track nest formation and nesting success rates, and 10 months after establishment all ponds were drained, recruits counted, and fin clips collected for genetic parentage analysis. A series of candidate generalized linear mixed models were compared using Akaike's information criterion and likelihood ratio tests to assess the relative importance of fishing treatment and year, along with other relevant variables in predicting nest success, recruitment, and reproductive success. We observed significant reductions in nest success rates (z = −2.13, P = 0.03) but not recruitment levels (z = −1.31, P = 0.19), in populations that were bed fished relative to control ponds. Capture history poorly predicted individual reproductive success and the number of adults that contributed to fall recruitment did not differ by treatment (χ2 = 0.06, P = 0.81). Results from this study indicated that bed‐fishing practices may have some impacts on individual nest success but did not influence recruitment or overall reproductive success of Florida Bass at the population level.Received October 5, 2016; accepted February 28, 2017 Published online July 5, 2017

ОЦЕНКА СОВРЕМЕННОГО СОСТОЯНИЯ РЫБНОЙ ПРОМЫШЛЕННОСТИ: СТАТИСТИЧЕСКИЙ ОБЗОР И АНАЛИЗ СИТУАЦИИ

Fisheries in the Russian Federation is an economical sector that includes a complex of different activities ranging from forecasting the resource base of the industry to trading in fish products in the country and abroad. Fish industry in Russia has been rapidly developing, yet there can be outlined a number of factors impeding development of the industry. According to official statistic figures, the main source of fish products is live fish, fresh or chilled, which today is steadily decreasing (within 2010-2015 to 221. 000 t). Releasing juveniles of aquatic biological resources is also being gradually reduced (by 1082 mln species for the last 5 years). Against this background, there takes place the rise of fish exports to the CIS countries and far abroad, as well as sharp decline in fish import, which, in turn, leads to a decrease of fish products on the shop shelves in Russia. It has been stated that the main problems in the fish industry are the result of fishery ineffectiveness (great wear rate of fixed assets, operation of obsolete vessels, reducing the release of juveniles of aquatic biological resources), as well as of technological imperfection of fish processing industry. The article considers different ways of governmental support to businesses of aquaculture and fish processing, as well as promoting development of multiformat infrastructure and fisheries trade using the Murmansk region as an example. Improvement of the situation in fishing industry is expected due to fleet modernization, developing innovation technologies, reducing power intension, business subsidizing, organizing recreational and sport fisheries.