Estimation of fish consumption rates based on a creel angler survey of an urban river in New Jersey,USA

Abstract

A one-year angler intercept survey was conducted on the lower 17 miles of the Passaic River, an urban industrialized river that flows through Newark, New Jersey. The purpose of the survey was to collect data about anglers’ behaviors and fish consumption habits in order to calculate exposure factors for a human health risk assessment of the Study Area. This paper focuses on estimating site-specific fish consumption rates for LPRSA anglers that consume their catch. The study design included on-site interviews and counts (angler enumeration). Forty survey locations were included in the stratified random sampling plan; interviews were conducted on 136 days and counts on 164 days. After matching intercepts with the same angler, a total of 294 anglers were interviewed, of which 25 reported consuming their catch. LPRSA fishing trips ranged from 2 to nearly 50 annual trips for anglers who reported consuming their catch. Species caught and reported to be consumed included carp, catfish, white perch, smallmouth bass, and eel. The estimated mean and 90th percentile consumption rates for the population of consuming anglers are 5.0 and 8.8?g/day, respectively. Based on sensitivity analyses, the 90th percentile fish consumption rates range from approximately 4 to 18?g/day.     

An examination of the fish population in the River Trent, Nottinghamshire using angler catches

During this study, anglers caught over 580 kg of fish, comprising over 29 500 individuals of 14 species. Nine times as many gudgeon, Gobio gobio , as roach, Rutilus rutilus , were caught. Gudgeon represented 35.94% of the total catch weight compared with 44.64% for roach. The mean total catch per man-hour was 8.9 fish and the mean catch rate was 176 g per man-hour. Population estimates for fish longer than 12 cm for all species other than gudgeon and bleak, Alburnus alburnus , gave fish densities of 0.21 fish m⁻², the roach population was 0.15 m⁻², and that for dace Leuciscus leuciscus , 0.02 m⁻². The population density for all sizes of all species caught was estimated to be 2.25 fish m⁻².
The fish biomass available to the angler was 447 kg ha⁻². The rate of exploitation of the fishery over the period of sampling was high at 17%, representing an annual exploitation rate of 94%.     

Gear type,species composition and economic value of fisheries in the mangroves of Pak Phanang,Thailand

Fishing gear and methods, catch composition, annual catch numbers and the monetary value of fisheries based in the mangroves of Pak Phanang, Nakhon Si Thamarat province, Thailand, were studied from September 2004 to February 2005. The fishing gear and methods were surveyed by visual observation and interviews. Sample catches were taken for each type of fishing gear and method. Semi-closed questionnaire surveys were conducted among fishers, local traders, local administrative officers and related organizations to derive information on utilized species, gear and methods, fisher and fishery status, and trading and catch price. The Pak Phanang mangrove fishery has three types of multi-species capture gear: channel traps, gill nets and lift nets. It also has three kinds of single-species (group) gear/methods: crab traps, catfish hooks and hand capture using a long tail fishing boat. A total of 57 fish species in 27 families, and 23 shell fish species in 8 families were recorded from the catch samples. Penaeid shrimp (25%), and ambassid (31%) and mugilid (24%) fishes were the abundant groups in the channel traps, while ariid (36%) and mugilid (19%) fishes were abundant in the lift net catches. Ambassid (42%) fish dominated the gill net catches. Species richness (number of species) varied depending on sampling month and type of fishing gear. The total annual catch and its monetary value were estimated to be 442–551 tons and US $368,038–733,973, respectively. The estimated annual catch per unit area of mangrove was 63–79 kg ha⁻¹, which generated a market value of US $368,038–733,973, respectively. The estimated annual catch per unit area of mangrove was 63–79 kg ha⁻¹, which generated a market value of US 52–105.     

Performance of circle hooks in a mixed-species recreational fishery

The effects of the circle-hook on hooking injury, fish size and catch rates were evaluated for mixed-species recreational boat fisheries in the Balearic Islands (NW Mediterranean). The relationships between deep-hooking incidence (the main cause of fish mortality) and hook type (circle hooks vs conventional J-hooks), fish size, and angler were tested. Results demonstrated that the size of the fish was the most important predictor of deep-hooking incidence, as a larger fish size resulted in an increase in deeper wounds. Hook type also had a significant effect on the deep-hooking rate. Specifically, the deep-hooking rate of the most frequently-caught species, Diplodus annularis (L.) and Coris julis (L.), was reduced by greater than half with the circle hooks. The mean size of the fish caught and the unhooking time were not affected by the use of circle hooks. Finally, their use resulted in no change in the catch per unit effort (CPUE) compared to conventional hooks for both univariate and multivariate procedures. Hence, circle hooks are a promising conservation tool for marine resources when linked with catch-and-release strategies.     

Hook performance and selectivity of Eurasian perch,Perca fluviatilis (Linnaeus, 1758) in the Åland Archipelago,Finland

The effects of two hook‐types (circle or J hook) fished with two different baits (red worms Eisenia spp., or cyprinid fishes) were examined for deep‐hooking, catch rate, mean total length, and selectivity of Eurasian perch, Perca fluviatilis, in the Åland Archipelago, Finland. The perch population available to hook‐and‐line gear was sampled with multipanel gillnets, with panels ranging from 10 to 60 mm in stretched mesh diameter. The effect of each hook then was examined for each bait by conditioning the size distributions of hook‐and‐line catches on the size distribution of perch collected with gillnets to estimate selectivity. The proportion of deeply‐hooked perch was 4.8 times greater for J hooks (0.21) than circle hooks (0.04) baited with worms and 3.7 times greater for J hooks (0.33) than circle hooks (0.09) baited with fish. Catch rates were significantly different between the two baits but not between the two hooks, with the greatest catch rate observed for the circle hook baited with worms. There was no significant difference in perch total length between the two hooks, but there was a significant difference between the two baits, with the fish bait catching significantly larger perch. Perch selection peaks between the two hooks differed by only 13.8 mm, but the selection peak with fish bait (236.4 mm TL) was 119.9 mm greater than the selection peak with the worm bait (116.5 mm TL). A substantially lesser incidence of deep hooking support the conservation benefits of circle hook use for perch, especially when catch‐and‐release is practiced. Using fish baits similar in size to those used in this experiment can avoid potentially harmful interactions between relatively small perch and anglers who place little importance on catch motives but whose satisfaction is still catch‐dependent.     

Stock enhancement to address multiple recreational fisheries objectives: an integrated model applied to red drum Sciaenops ocellatus in Florida

An integrated socioecological model was developed to evaluate the potential for stock enhancement with hatchery fishes to achieve socioeconomic and conservation objectives in recreational fisheries. As a case study, this model was applied to the red drum Sciaenops ocellatus recreational fishery in the Tampa Bay estuary, Florida, U.S.A. The results suggest that stocking of juvenile fish larger than the size at which the strongest density dependence in mortality occurs can help increase angler satisfaction and total fishing effort (socioeconomic objectives) but are likely to result in decreases to the abundance of wild fishes (a conservation objective). Stocking of small juveniles that are susceptible to density‐dependent mortality after release does not achieve socioeconomic objectives (or only at excessive cost) but still leads to a reduction of wild fish abundance. The intensity and type of socioeconomic gains depended on assumptions of dynamic angler‐effort responses and importance of catch‐related satisfaction, with greatest gains possible if aggregate effort is responsive to increases in abundance and satisfaction that are greatly related to catch rates. These results emphasize the view of stock enhancement, not as a panacea but rather as a management tool with inherent costs that is best applied to recreational fisheries under certain conditions.     

Species‐specific preferences of German recreational anglers for freshwater fishing experiences,with emphasis on the intrinsic utilities of fish stocking and wild fishes

To answer the question, whether anglers have an intrinsic preference for stocking or a preference for catch outcomes (e.g. catch rates) believed to be maintained by stocking, a discrete choice experiment was conducted among a sample of anglers (n = 1335) in Lower Saxony, Germany. After controlling for catch aspects of the fishing experience, no significant influence of two stocking attributes (stocking frequency and composition of the catch in terms of wild v. hatchery fishes) on the utility gained from fishing was found for any of the freshwater species that were studied. It was concluded that the previously documented large appreciation of fish stocking by anglers may be indicative of an underlying preference for sufficiently high catches rather than reflect an intrinsic preference for stocking or the catching of wild fishes per se.     

Selective exploitation of early running fish may induce genetic and phenotypic changes in Atlantic salmon

Genetic evidence for the selective exploitation by anglers of early running fish was examined in four Iberian Atlantic salmon populations using protein and mtDNA markers. The populations studied had been exploited exclusively by anglers since 1949 during a fixed fishing season that ran approximately from March to July. Genetic variation at six protein loci was small and was accounted for by the MEP‐2 * and MDH‐3,4 * polymorphisms, which generally remained stable over time and were in Castle–Hardy–Weinberg equilibrium during the fishing season. Early running fish that had spent multiple winters at sea (MSW) generally had higher frequencies of the common MEP‐2 *(100) allele than did late running, one sea winter (1SW) grilse that were significantly smaller and tended to escape the fishery. Spawners differed from angler caught fish in their mtDNA frequencies and consistently had a lower sea‐age and a smaller body size. Spawners also smolted at an older age and displayed lower frequencies of the MEP‐2 *(100) allele in three of the four populations studied. These results suggest that in these rivers anglers selectively exploit a distinct component of the population and inadvertently cause a differential mortality of genetic types that is likely to be detrimental to population viability.     

Assessing the potential biological implications of recreational inshore fisheries on sub‐tidal fish communities of Azores (north‐east Atlantic Ocean) using catch and effort data

Recreational inshore fishing activities practiced on Faial and Pico Islands (Azorean archipelago) were surveyed between October 2004 and September 2005. Recreational inshore fishers employ three main methods of fishing (shore angling, spear fishing and intertidal collecting). The method that demanded the highest fishing effort (number of fishing operations) was shore angling, followed by intertidal collecting and spear fishing. Shore angling produced the highest diversity of catch composition (38), which is in part explained by the seven fishing techniques used by shore anglers. The estimates of annual catch were higher for shore angling than spear fishing (51·2 and 6·3 t) even though they were lower than commercial artisanal fishing (442 t). The weighted mean trophic level and vulnerability index values in the fish catch were higher for spear fishing (3·4 and 50·9) than for shore angling (3·1 and 44·5). Cumulative pressure by different recreational fishing activities was detected on species already subject to a heavy pressure from Azorean commercial fishing, and on vulnerable and top‐predator species. There are important biological and ecological implications whereby fishery managers should implement additional regulations such as prohibiting catches of the most vulnerable species.     

Using Tournament Angler Data to Rapidly Assess the Invasion Status of Alien Sport Fishes (Micropterus spp.) in Southern Africa

Fishes are one of the most commonly introduced aquatic taxa worldwide, and invasive fish species pose threats to biodiversity and ecosystem function in recipient waters. Considerable research efforts have focused on predicting the invasibility of different fish taxa; however, accurate records detailing the establishment and spread of invasive fishes are lacking for large numbers of fish around the globe. In response to these data limitations, a low-cost method of cataloging and quantifying the temporal and spatial status of fish invasions was explored. Specifically, angler catch data derived from competitive bass angling tournaments was used to document the distribution of 66 non-native populations of black bass (Micropterus spp.) in southern Africa. Additionally, catch data from standardized tournament events were used to assess the abundance and growth of non-native bass populations in southern Africa relative to their native distribution (southern and eastern United States). Differences in metrics of catch per unit effort (average number of fish retained per angler per day), daily bag weights (the average weight of fish retained per angler), and average fish weight were assessed using catch data from 14,890 angler days of tournament fishing (11,045 days from South Africa and Zimbabwe; 3,845 days from the United States). No significant differences were found between catch rates, average daily bag weight, or the average fish weight between countries, suggesting that bass populations in southern Africa reach comparable sizes and numbers relative to waters in their native distribution. Given the minimal cost associated with data collection (i.e. records are collected by tournament organizers), the standardized nature of the events, and consistent bias (i.e. selection for the biggest fish in a population), the use of angler catch data represents a novel approach to infer the status and distribution of invasive sport fish.     

Characteristics of Ontario muskellunge (Esox masquinongy) fisheries based on volunteer angler diary information

This paper consolidates and summarizes information on Ontario muskellunge, Esox masquinongy, sport fisheries derived from angler diary programs sponsored by the Ontario Ministry of Natural Resources (OMNR) and Muskies Canada Incorporated (MCI) from 1979 to 2004. Interest in muskellunge as a sport fish has increased substantially over the past 10–15 years. Muskellunge catches were found to be highly correlated with angling effort. Catch rates, expressed in terms of catch-per-unit-of-effort (CUE), have improved over the past decade to the point where, in 2001, the provincial CUE was 0.119. The long term catch rate is 0.069. This improvement in angling quality is attributed to new minimum size limit regulations and increased catch-and-release angling practices. Over the period from 1979–2004, release rates by muskellunge anglers have averaged 94%. Based on a sample size of 9,499 fish, the mean size of angled muskellunge over the past 26 years was 37.0 inches (94 cm). Numerous fish exceeding 50 inches (127 cm) are angled from Ontario waters each year. The incidence of lymphosarcoma, a highly contagious, malignant blood cancer, has averaged only 2% since 1979. Based on an analysis of this information, Ontario’s muskellunge fisheries appear to be stable and sustainable. Volunteer angler diary programs provide an accurate and cost-effective means to monitor the status of muskellunge fisheries in Ontario.     

The use of angler diary surveys to evaluate long-term changes in muskellunge populations on Lake of the Woods, Ontario

Reported improvements in the muskellunge angling fishery on Lake of the Woods, Ontario over the last two decades have paralleled an increase in the practice of catch and release angling, and an increase in minimum size regulations for this species. The overall status of muskellunge populations in this large, complex lake has proven difficult to monitor using standard assessment methods. A volunteer muskellunge angler diary program, established in 1988, has provided a cost effective method of gathering a large amount of information with which to track this fishery and associated populations. Results from angling diaries indicated increased angling effort, catch and success rates for muskellunge on Lake of the Woods since the early 1990s. Although the month of July accounted for the majority of angling effort and catch, angling success rates and sizes of fish reported in diaries improved monthly into the late fall. Angling success rates were consistently higher in angling diaries than from creel surveys, but both survey types showed similar long-term trends in the fishery. Angler diary data, incorporating both the numbers of fish caught and/or seen by anglers, were used to calculate catch equality indices which proved to be sensitive to changes in population abundance. Increased minimum length regulations for muskellunge during 1987–2001 have been largely responsible for a decline in harvest rates from an estimated 36% in 1986 to 0% since 1999. Although higher size limits have yet to produce more quality-sized fish in angler catches, diary survey data, supported by recent improvements in catch rates from assessment gill nets, would indicate that muskellunge recruitment has increased. This article concludes with a brief review of how muskellunge angler diary data has been used in the past, including recommendations to minimize biases associated with this survey method.     

Fishery-Induced Changes in the Subtropical Pacific Pelagic Ecosystem Size Structure: Observations and Theory

We analyzed a 16-year (1996–2011) time series of catch and effort data for 23 species with mean weights ranging from 0.8 kg to 224 kg, recorded by observers in the Hawaii-based deep-set longline fishery. Over this time period, domestic fishing effort, as numbers of hooks set in the core Hawaii-based fishing ground, has increased fourfold. The standardized aggregated annual catch rate for 9 small (<15 kg) species increased about 25% while for 14 large species (>15 kg) it decreased about 50% over the 16-year period. A size-based ecosystem model for the subtropical Pacific captures this pattern well as a response to increased fishing effort. Further, the model projects a decline in the abundance of fishes larger than 15 kg results in an increase in abundance of animals from 0.1 to 15 kg but with minimal subsequent cascade to sizes smaller than 0.1 kg. These results suggest that size-based predation plays a key role in structuring the subtropical ecosystem. These changes in ecosystem size structure show up in the fishery in various ways. The non-commercial species lancetfish (mean weight 7 kg) has now surpassed the target species, bigeye tuna, as the species with the highest annual catch rate. Based on the increase in snake mackerel (mean weight 0.8 kg) and lancetfish catches, the discards in the fishery are estimated to have increased from 30 to 40% of the total catch.     

Assessing Fishers' Support of Striped Bass Management Strategies

Incorporating the perspectives and insights of stakeholders is an essential component of ecosystem-based fisheries management, such that policy strategies should account for the diverse interests of various groups of anglers to enhance their efficacy. Here we assessed fishing stakeholders’ perceptions on the management of Atlantic striped bass (Morone saxatilis) and receptiveness to potential future regulations using an online survey of recreational and commercial fishers in Massachusetts and Connecticut (USA). Our results indicate that most fishers harbored adequate to positive perceptions of current striped bass management policies when asked to grade their state’s management regime. Yet, subtle differences in perceptions existed between recreational and commercial fishers, as well as across individuals with differing levels of fishing experience, resource dependency, and tournament participation. Recreational fishers in both states were generally supportive or neutral towards potential management actions including slot limits (71%) and mandated circle hooks to reduce mortality of released fish (74%), but less supportive of reduced recreational bag limits (51%). Although commercial anglers were typically less supportive of management changes than their recreational counterparts, the majority were still supportive of slot limits (54%) and mandated use of circle hooks (56%). Our study suggests that both recreational and commercial fishers are generally supportive of additional management strategies aimed at sustaining healthy striped bass populations and agree on a variety of strategies. However, both stakeholder groups were less supportive of harvest reductions, which is the most direct measure of reducing mortality available to fisheries managers. By revealing factors that influence stakeholders’ support or willingness to comply with management strategies, studies such as ours can help managers identify potential stakeholder support for or conflicts that may result from regulation changes.     

Muskellunge in Missouri: a 10 year strategic plan

In 1995, a 10-year strategic plan for muskellunge program management in Missouri was developed by the Missouri Department of Conservation. Our mission was to efficiently produce and manage muskellunge in order to provide high-quality angling opportunities in suitable, well-distributed lakes throughout the state. The first goal was to increase the number and improve the distribution of muskellunge fisheries in small lakes. In 1995, our three existing muskellunge fisheries were in west central, northwest, and north Missouri. Six additional lakes were stocked with muskellunge from 1995 to 2001 in southeast, northeast, southwest, and central Missouri, plus the St. Louis area. The second goal was to maintain density and size structure of muskellunge populations commensurate with muskellunge angler expectations. Our objective was for muskellunge anglers to catch a muskellunge at least 91 cm (36 in.) in 20–40 h of angling. The Show-Me Muskie Project, a volunteer angler diary program, was initiated in 1996 to help evaluate this objective. The third goal was to inform Missouri anglers about increased opportunities for high-quality muskellunge fishing. We developed a muskellunge web page, created a release poster, updated our muskellunge brochure, published magazine articles, and mailed biannual letters to our Show-Me Muskie Project cooperators.     

Recreational fishing impacts on threatened river sharks: A potential conservation issue

The Adelaide River in Australia's Northern Territory is a popular recreational fishing area, as well as habitat for threatened and protected river sharks (Glyphis species). Both the Critically Endangered Speartooth Shark (Glyphis glyphis) and Endangered Northern River Shark (Glyphis garricki) are identified here in illegal catches from recreational angling. The identification of a decayed shark specimen using a DNA barcoding‐like approach is the first such application to the identification of protected sharks in a recreational fishery. While the extent of catches by recreational anglers is unknown, the threatened status of these sharks, their suspected low population sizes, restricted distributions and importance of the Adelaide River as a nursery area call for the consideration of this as a potential conservation issue. As such, appropriate measures should be taken to reduce interactions with recreational anglers. The primary target species in the river is the iconic sportfish, Barramundi, which is predominantly caught by unbaited lure. Sharks are rarely caught on lure, allowing an opportunity for mitigation to focus on a fishing activity (baited hooks) which would limit any regulatory impact on popular lure fishing. Potential mitigation measures range from increased angler education and compliance checks, to the implementation of a spatial closure to baited hook fishing (a lure‐only zone). Such measures may assist in meeting a stated objective of the Australian Government's river shark Recovery Plan to ‘reduce and, where possible, eliminate adverse impacts of recreational fishing'.     

Changes in the species composition of anglers' catches in the River Trent (England) between 1969 and 1984

Data on anglers' catches on the River Trent were collected for the seasons 1969/70 to 1983/84 using postal questionnaires. During this period 60.4t of fish were caught during a total fishing effort of 526 871 man-h or 60.15 man-years, and more than 20 species of fish were recorded. The percentage of anglers making a catch (70–80%) and the catch per unit effort, mean 114.7g man-h ⁻¹, were comparable with those reported for other waters.
Roach and gudgeon were the most commonly captured species with chub, bleak, bream, eels and dace also forming major components of anglers' catches. Since 1969 chub, bream, eels and perch have made an increasingly greater contribution to catches, coupled with a decline in numbers of roach and dace. It is suggested that improvement in water quality and its implication on interspecific competition was the most likely cause of the changes.     

Shark bycatch in the experimental tuna longline fishery in Lakshadweep Sea,India

Bycatch from the experimental longline operations in the Lakshadweep Sea were studied. The experiments were conducted on converted Pablo boats, originally used for pole and line fishing operations, to capture skipjack tuna in the Lakshadweep Islands. The overall bycatch rate was very high, with a mean hooking rate of 8.05/1000 hooks compared to the targeted tuna catch (1.75/1000 hooks). Bycatch contributed 82.4% of the catch in comparison to the tuna (17.6%) Thunnus albacares, in the longline operations. Silky shark (Carcharhinus falciformes) with 89.9% was the dominant shark species followed by C. amblyrhynchos, Galeocerdo cuvier, Alopias pelagicus, Negapriion acutedens and Sphyrna lewinii with 4.7, 2.7, 1.4, 0.7 and 0.7%, respectively. Sharks contributed to 74.1% of the catch, followed by 15.7% sailfishes and 10.2% miscellaneous fishes. Higher bycatch rates were evident during evening hours compared to mornings, but the results were not significant statistically. Studies on the effects of depth on the overall fishing performance and species selectivity failed to establish any significant relationship at a depth range of 35–100 m. Soaking time had a significant effect on bycatch rates. The hooking rate of sharks declined with an increase in soaking time. Considering the high shark bycatch in the fishery, an accurate monitoring of the longline fish catches in the Lakshadweep waters is an important step towards ensuring the sustainability of other populations, especially sharks.     

Assessing the impact of toothed whale depredation on socio-ecosystems and fishery management in wide-ranging subantarctic fisheries

Marine predators feeding on fisheries catches directly on the fishing gear, a behaviour termed “depredation”, has emerged as a major human-wildlife conflict globally, often resulting in substantial socio-economic and ecological impacts. This study investigated the extent of this conflict in commercial Patagonian toothfish (Dissostichus eleginoides) fisheries across subantarctic waters where both killer whales (Orcinus orca) and sperm whales (Physeter macrocephalus) feed on toothfish caught on longline hooks. Using long-term datasets from six major fishing areas, from southern Chile to the Indian Ocean sector of the Southern Ocean, statistical models were developed to quantify the catch removals due to whale depredation interactions. The results indicated that these removals were large, totalling more than 6600 t of toothfish between 2009 and 2016 with an annual mean of 837 t [95% CI 480–1195 t], comprised of 317 t [232–403 t] and 518 t [247–790 t] removed by killer whales and sperm whales, respectively. Catch removals greatly varied between areas, with the largest estimates found at Crozet, where on average 279 t [179–379 t] of toothfish per year, equivalent to 30% [21–37%] of the total catches. Together, these findings provide metrics to assess the impacts of depredation interactions on the fishing industry, whale populations, fish stocks and associated ecosystems. With an estimated $15 M USD worth of fish depredated every year, this study highlights the large geographic scale and economic significance of the depredation issue and its potential to compromise the viability of some toothfish fisheries which are the primary socio-economic activity in subantarctic regions.