Catch Record Research Articles

Characterizing Antarctic fish assemblages using eDNA obtained from marine sponge bycatch specimens

International conservation goals have been set to mitigate Southern Ocean ecosystem deterioration, with multiple monitoring programs evaluating progress towards those goals. The scale of continuous monitoring through visual observations, however, is challenged by the remoteness of the area and logistical constraints. Given the ecological and economic importance of the Southern Ocean, it is imperative that additional biological monitoring approaches are explored. Recently, marine sponges, which are frequently caught and discarded in Southern Ocean fisheries, have been shown to naturally accumulate environmental DNA (eDNA). Here, we compare fish eDNA signals from marine sponge bycatch specimens to fish catch records for nine locations on the continental shelf (523.5–709 m) and 17 from the continental slope (887.5–1611.5 m) within the Ross Sea, Antarctica. We recorded a total of 20 fishes, with 12 fishes reported as catch, 18 observed by eDNA, and ten detected by both methods. While sampling location was the largest contributor to the variation observed in the dataset, eDNA obtained significantly higher species richness and displayed a significantly different species composition compared to fish catch records. Overall, eDNA read count correlated more strongly with fish abundance over biomass. Species composition correlated on a regional scale between methods, however eDNA signal strength was a low predictor of catch numbers at the species level. Our results highlight the potential of sponge eDNA monitoring in the Southern Ocean by detecting a larger fraction of the fish community compared to catch recordings, thereby increasing our knowledge of this understudied ecosystem and, ultimately, aiding conservation efforts.

Assessment of the Bering-Chukchi-Beaufort Seas stock of bowhead whales using Bayesian model averaging

Bayesian estimation methods are used to fit an age- and sex-structured population model to available data on abundance and stageproportions (i.e. calves/mature animals in the population) for the Bering-Chukchi-Beaufort Seas stock of bowhead whales (Balaena mysticetus). The analyses consider three alternative population modelling approaches: (1) modelling the entire population trajectory from 1848, using the ‘backwards’ method where the trajectory is back-calculated based on assigning a prior distribution to recent abundance; (2) modelling only the recent population trajectory, using the ‘forwards from recent abundance’ method, where the population is projected forwards from a recent year and the abundance in that year is not assumed to be at carrying capacity; and (3) a version of (2) that ignores density-dependence. The ‘backwards’ method leads to more precise estimates of depletion level. In contrast, the ‘forwards from recent abundance’ method provides an alternative way of calculating catch-related quantities without having to assume that the catch record is known exactly from 1848 to the present, or having to assume that carrying capacity has not changed since 1848. Not only are all three models able to fit the abundance data well, but each is also able to remain consistent with available estimates of adult survival and age of sexual maturity. Sensitivity to the stage-proportion data and the prior distributions for the life history parameters indicates that use of the 1985 stage-proportion data has the greatest effect on the results, and that those data are less consistent with data on trends in abundance and age of sexual maturity. The analyses indicate that the population has approximately doubled in size since 1978, and the ‘backwards’ analyses suggest that the population may be approaching carrying capacity, although there is no obvious sign in the data that the population growth rate has slowed. Bayes factors are calculated to compare model fits to the data. However, there is no evidence for selecting one model over another, and furthermore, the models considered in this study result in different posterior distributions for quantities of interest to management. Posterior model probabilities are therefore calculated and used as weights to construct Bayesian model-averaged posterior distributions for outputs shared among models to take this ambiguity into account. This study represents the first attempt to explicitly quantify model uncertainty when conducting a stock assessment of bowhead whales.

Law Enforcement Against Unreported Fishing: What Does Beyond the Catch Record?

Transparency is significant in highly migratory fisheries. The reliability of the catch data is essential for decisions of internationally agreed targets. Nevertheless, the data accuracy will much depend on each state's performance. Focusing on unreported catches of migratory fish, this study highlights the Thunnus Macoyyi (Southern Bluefin Tuna) fishing in Indonesia, as this fish species had experienced for being the limelight of unreported fishing allegations. The main objective is to reveal what are the difficulties that Indonesia is facing on its responsibility to maintain the accuracy of the catch record. Accordingly, the study examines two points by applying the pure legal method and doctrinal approach. Firstly, the international legal framework towards unreported fishing by analysing three main instruments such as the UNCLOS 1982, the UNFSA 1995, and the CCSBT policies. Secondly, it examines Indonesia law enforcement as a State party of regional fisheries organisation. It argues that the international authority could not be completely extended to a State's domestic fishing area. Thus, it gives more discretion to the national law to enforce compliance. Lesson learned from the case study of Indonesia's southern bluefin tuna contributes to unreported fishing literature and allows us to expose the legal gap remained in managing highly migratory fish stocks.

An additional record of the non-indigenous species (NIS) Seriola fasciata from the southern coast of Sicily (Central Mediterranean Sea)

An additional record of the non-indigenous species (NIS) Seriola fasciata from the southern coast of Sicily (Central Mediterranean Sea) is here described in this note. The catch record is the first in the area and confirms the key role of the area for NIS spreading. In addition, an updated map of its spatial distribution is provided as well as a discussion on the possible misidentification and competition with the native greater amberjack Seriola dumerili.

Captura incidental de um leão-marinho-sul-americano na pesca de arrasto de parelha no sul do Brasil

The population of the South American sea lion, Otaria flavescens (Shaw, 1800), in Uruguay is declining at an annual rate of 1.6 to 2.0%. Although the reasons are still unknown, interactions with fishing activities have been identified as a major cause. The individuals that arrive along the coast of Brazil come from the breeding colonies off Uruguay after their breeding period. We report here the first record of incidental catch of South American sea lions in Brazilian waters by a pair trawl. On July 17th, 2008 a young male of South American sea lion was incidentally caught during a commercial pair trawl fishing trip along the southern Brazilian coast (32o57’S, 52o31’W), in a depth ranging from 15 to 20 m. Despite being punctual, this record is an evidence of a potential major threat to South American sea lions in southern Brazil and Uruguay, since trawl industrial fishing is a very important economic activity in South Brazil. Keywords: Pinnipeds, Otaria flavescens , human impact, human-carnivore conflicts, fishery interactions.

Trends in insect catch at historic properties

Abstract Warmer climate has the potential to increase the number of insect pests in historic properties. This possibility has been explored using the catch from some thirty thousand insect traps laid out in English Heritage properties over more than a decade. The trapping programme resulted from an increasing focus on integrated pest management (IPM). Trapping has been more frequent in London and the Southeast. Quarterly inspection and replacement has led to a detailed record of catch. Although these data were collected for management purposes, they offer the potential to assess the impact of environmental change. Variation in the number of traps placed out requires data to be expressed as catch rate (insects caught per trap). The record suggests an increase in the average catch of booklice ( Liposcelis bostrychophila ) summed across all the properties examined over the period 2000–2012. There was a striking increase in the prevalence of the webbing clothes moth ( Tinea pellionella ) even when accounting for the increasing use of attractant pheromones in traps. In addition, infestations (i.e. > 10 insects per trap) also seemed to increase. However, these increases over time are not likely to be attributable to increasing temperatures. Nevertheless, the catch rate for woolly bear larvae ( Anthrenus spp.) at the London properties showed a weak correlation with temperature in the warmer seasons. If temperature were to increase across the 21st century, a dramatic increase in catch rate would be expected. However, it is hardly likely as the abundance of insects is not driven by temperature alone. Other factors such as: food, habitat, access points, housekeeping and indoor climate can all have an impact on insect numbers and on infestations within a property.

Species identification and likely catch time period of whale bones from South Georgia

AbstractSkeletal remains of baleen whales killed during the onset of 20th century commercial whaling lie scattered across the shores and abandoned whaling stations of the subantarctic island of South Georgia. Here we report on genetic species identification of whale bones collected from South Georgia using standard historical DNA protocols. We amplified and sequenced short fragments of the mitochondrial DNA (mtDNA) control region from 281 available bone samples. Of these, 231 provided mtDNA sequences of sufficient quality and length (174–194 bp) for species identification: 158 bones were identified as humpback whale (Megaptera novaeangliae), 51 bones were identified as fin whale (Balaenoptera physalus), 18 bones were identified as blue whale (B. musculus), two bones were identified as sei whale (B. borealis), one bone was identified as a southern right whale (Eubalaena australis), and one bone was identified as a southern elephant seal (Mirounga leonina). The prominence of humpback, fin, and blue whale bones in the sample collection corresponds to the catch record of the early years of whaling on the island of South Georgia (pre‐1915), prior to the depletion of these populations.

Correction: Two intense decades of 19th century whaling precipitated rapid decline of right whales around New Zealand and east Australia.

Right whales (Eubalaena spp.) were the focus of worldwide whaling activities from the 16th to the 20th century. During the first part of the 19th century, the southern right whale (E. australis) was heavily exploited on whaling grounds around New Zealand (NZ) and east Australia (EA). Here we build upon previous estimates of the total catch of NZ and EA right whales by improving and combining estimates from four different fisheries. Two fisheries have previously been considered: shore-based whaling in bays and ship-based whaling offshore. These were both improved by comparison with primary sources and the American offshore whaling catch record was improved by using a sample of logbooks to produce a more accurate catch record in terms of location and species composition. Two fisheries had not been previously integrated into the NZ and EA catch series: ship-based whaling in bays and whaling in the 20th century. To investigate the previously unaddressed problem of offshore whalers operating in bays, we identified a subset of vessels likely to be operating in bays and read available extant logbooks. This allowed us to estimate the total likely catch from bay-whaling by offshore whalers from the number of vessels seasons and whales killed per season: it ranged from 2,989 to 4,652 whales. The revised total estimate of 53,000 to 58,000 southern right whales killed is a considerable increase on the previous estimate of 26,000, partly because it applies fishery-specific estimates of struck and loss rates. Over 80% of kills were taken between 1830 and 1849, indicating a brief and intensive fishery that resulted in the commercial extinction of southern right whales in NZ and EA in just two decades. This conforms to the global trend of increasingly intense and destructive southern right whale fisheries over time.

Two Intense Decades of 19th Century Whaling Precipitated Rapid Decline of Right Whales around New Zealand and East Australia

Right whales (Eubalaena spp.) were the focus of worldwide whaling activities from the 16th to the 20th century. During the first part of the 19th century, the southern right whale (E. australis) was heavily exploited on whaling grounds around New Zealand (NZ) and east Australia (EA). Here we build upon previous estimates of the total catch of NZ and EA right whales by improving and combining estimates from four different fisheries. Two fisheries have previously been considered: shore-based whaling in bays and ship-based whaling offshore. These were both improved by comparison with primary sources and the American offshore whaling catch record was improved by using a sample of logbooks to produce a more accurate catch record in terms of location and species composition. Two fisheries had not been previously integrated into the NZ and EA catch series: ship-based whaling in bays and whaling in the 20th century. To investigate the previously unaddressed problem of offshore whalers operating in bays, we identified a subset of vessels likely to be operating in bays and read available extant logbooks. This allowed us to estimate the total likely catch from bay-whaling by offshore whalers from the number of vessels seasons and whales killed per season: it ranged from 2,989 to 4,652 whales. The revised total estimate of 53,000 to 58,000 southern right whales killed is a considerable increase on the previous estimate of 26,000, partly because it applies fishery-specific estimates of struck and loss rates. Over 80% of kills were taken between 1830 and 1849, indicating a brief and intensive fishery that resulted in the commercial extinction of southern right whales in NZ and EA in just two decades. This conforms to the global trend of increasingly intense and destructive southern right whale fisheries over time.

Meeting the Needs of the People: Fish Consumption Rates in the Pacific Northwest

Meeting the Needs of the People: Fish Consumption Rates in the Pacific Northwest

Decrease of Abalone Resources with Disappearance of Macroalgal Beds Around the Ojika Islands, Nagasaki, Southwestern Japan

Because abalone feed mainly on macroalgae, the disappearance of macroalgal beds would have negative effects on abalone. We investigated the relationship between abalone resources and quantitative or qualitative changes of algal beds in coastal waters around the Ojika Islands, Nagasaki Prefecture, southwestern Japan, from 1988 to 2011. During this period, the catch record of 2 abalone species—Haliotis discus discus and Haliotis gigantea—was examined, and the composition and abundance of macroalgae around the Ojika Islands was observed. The annual landing of abalone has decreased steadily from 91 mt in 1987 to 0.4 mt in 2011. The proportion of H. discus discus to the annual abalone landing has also changed; it was stable (30%–60%) between 1988 and 2000, less than 20% from 2004 to 2005, and increased from 2006, reaching more than 90% in 2010. The macroalgal beds have also changed during this period. The perennial Laminariales beds, consisting of Eisenia bicyclis and Ecklonia spp., had disappeared by 2003, shifting mostly to Sargassaceae (Sargassum macrocarpum) beds. After the Sargassaceae beds had disappeared by 2009, there have been no Laminariales or Sargassaceae beds except for spring algal beds (unusual perennial Sargassaceae beds that form dense stands from March to July and lose most thalli after maturing in August) in some fishing ports. The results suggest a differential detrimental effect of the disappearance of macroalgal beds on abalone, with different species having different effects. After 2009, when no perennial Laminariales or Sargassaceae beds were present, there were no mature individuals of H. gigantea, with no recruitment at the juvenile stage of the latter at major fishing grounds. Reformation of the macroalgal beds is indispensable to sustain or restore the H. gigantea population. On the other hand, because most H. discus discus are able to mature, they can sustain a viable population under this condition.

Incidental Catch and New Distributional Records of Asteroids by Bottom Trawling Activities from Southeast Coast of India

A study was undertaken for a period of one year between January 2011 and December 2011 from Parangipettai coastal waters (Mudasalodai and Annankoil) southeast coast of India. Present study discusses the distribution and systematic position of asteroids from these study areas. There are 8 species viz., Luidia maculate (15.6%), Astropecten indicus (54.9%), A. hemprichi (6.9%), Stellaster equestris (21.7%) and Anthenea pentagonula (0.1%), Protoreaster linki (0.2%), Pentacerasterr regulus (0.1%) and P. affinis (0.2%) was observed. 4 species viz., Luidia maculata, Astropecten indicus, A. hemprichi, Stellaster equestris are commonly available in both stations, where as P. lincki and P. regulus observed only from station II and Anthenea pentagonula is newly recorded from station I. diversity indices of Shannon (H’), Simpson (1-D), Evenness, Mergalef’s species richness and cluster analysis, MDS also derived based on the number of observed species. Species diversity, abundance, richness and evenness are higher in station I than the station II. The present study concluded that station I has higher resources of asteroids (89.1%) than station II (10.9%) and this study also provides additional information about diversity ofasteroids.

Long-term population size of the North Atlantic humpback whale within the context of worldwide population structure

Once hunted to the brink of extinction, humpback whales (Megaptera novaeangliae) in the North Atlantic have recently been increasing in numbers. However, uncertain information on past abundance makes it difficult to assess the extent of the recovery in this species. While estimates of pre-exploitation abundance based upon catch data suggest the population might be approaching pre-whaling numbers, estimates based on mtDNA genetic diversity suggest they are still only a fraction of their past abundance levels. The difference between the two estimates could be accounted for by inaccuracies in the catch record, by uncertainties surrounding the genetic estimate, or by differences in the timescale to which the two estimates apply. Here we report an estimate of long-term population size based on nuclear gene diversity. We increase the reliability of our genetic estimate by increasing the number of loci, incorporating uncertainty in each parameter and increasing sampling across the geographic range. We report an estimate of long-term population size in the North Atlantic humpback of ~112,000 individuals (95 % CI 45,000–235,000). This value is 2–3 fold higher than estimates based upon catch data. This persistent difference between estimates parallels difficulties encountered by population models in explaining the historical crash of North Atlantic humpback whales. The remaining discrepancy between genetic and catch-record values, and the failure of population models, highlights a need for continued evaluation of whale population growth and shifts over time, and continued caution about changing the conservation status of this population.

목시조사(2000-2010)에 의한 한국 연안 고래류의 종류 및 분포

In the late 1970s, the National Fisheries Research & Development Institute (NFRDI) started cetacean research to submit the Korean whale catch record to the International Whaling Commission. This continued until the moratorium on commercial whaling in 1986. The NFRDI resumed cetacean research with a pilot whale sighting survey in 1999. Subsequently, the NFRDI has conducted 53 cetacean sighting surveys within the Korean exclusive economic zone between 2000 and 2010. The surveys took a total of 760 days and cruising for 23,866 nautical miles. The finless porpoise Neophocaena asiaeorientalis was sighted most frequently (735 times), followed by the minke whale Balaenoptera acutorostrata (396 times), the long-beaked common dolphin Delphinus capensis (102 times), and the Pacific white-sided dolphin Lagenorhynchus obliquidens (27 times). Minke whales were distributed in the Yellow Sea and coastal area of the East Sea from spring to fall. Pacific white-sided dolphin sightings were restricted to the middle and upper coastal areas of the East Sea in summer. Common dolphins were sighted from east of the southern coast to the eastern coast of the Korean Peninsula from spring to fall. Finless porpoise occurred in all Korean coastal areas, except the middle and upper eastern coast.

Historical abundance of Puget Sound steelhead, Oncorhynchus mykiss, estimated from catch record data

We used reported commercial catch data and historical information regarding unreported catches to estimate the abundance of winter steelhead, Oncorhynchus mykiss , in Puget Sound rivers in 1895, the year in which the peak commercial catch of steelhead occurred. We employed a Bayesian analysis to address the uncertainties associated with the estimation process and report abundance estimates for four large northern Puget Sound rivers and for the remaining aggregate of rivers and streams in Puget Sound. The central 90% of the posterior distribution of total abundance ranged from 485 000 to 930 000, with a mode of 622 000. Compared with the 25-year average abundance for all of Puget Sound of 22 000 for the 1980–2004 period, our results show that current abundance is likely only 1%–4% of what it was prior to the turn of the 20th century. Loss of freshwater habitat alone can account for this reduction in abundance only if there was an extraordinary decline in productivity. Our estimates of historical abundance should better inform the development of recovery goals for Puget Sound steelhead.

Applying Fishers' ecological knowledge to construct past and future lobster stocks in the Juan Fernández Archipelago, Chile.

Over-exploited fisheries are a common feature of the modern world and a range of solutions including area closures (marine reserves; MRs), effort reduction, gear changes, ecosystem-based management, incentives and co-management have been suggested as techniques to rebuild over-fished populations. Historic accounts of lobster (Jasus frontalis) on the Chilean Juan Fernández Archipelago indicate a high abundance at all depths (intertidal to approximately 165 m), but presently lobsters are found almost exclusively in deeper regions of their natural distribution. Fishers' ecological knowledge (FEK) tells a story of serial depletion in lobster abundance at fishing grounds located closest to the fishing port with an associated decline in catch per unit effort (CPUE) throughout recent history. We have re-constructed baselines of lobster biomass throughout human history on the archipelago using historic data, the fishery catch record and FEK to permit examination of the potential effects of MRs, effort reduction and co-management (stewardship of catch) to restore stocks. We employed a bioeconomic model using FEK, fishery catch and effort data, underwater survey information, predicted population growth and response to MR protection (no-take) to explore different management strategies and their trade-offs to restore stocks and improve catches. Our findings indicate that increased stewardship of catch coupled with 30% area closure (MR) provides the best option to reconstruct historic baselines. Based on model predictions, continued exploitation under the current management scheme is highly influenced by annual fluctuations and unsustainable. We propose a community-based co-management program to implement a MR in order to rebuild the lobster population while also providing conservation protection for marine species endemic to the Archipelago.

Estimación del crecimiento de Lutjanus peru (Pisces: Lutjanidae) basado en capturas artesanales experimentales realizadas en el Parque Nacional Natural Gorgona y su área de infiuencia, océano Pacífico colombiano

Gorgona Natural National Park covers 1600 ha of insular territory and 60087 ha of protected marine area in the Eastern Pacific Ocean (02°49'00N-03°06'00N and 78°06'00W-78°18'00W), and is located 27 km off the continent (Narino, Colombia). A prohibition on fishing activities in Gorgona Park has resulted in sustained conflicts with small-scale and industrial fishermen. Therefore, Gorgona Park began a project to evaluate the bottom fish resources and other communities in the park's area of influence. This study was designed to evaluate the state of the resources and to determine conservation strategies for them. Lutjanus peru, a seasonal resource recorded in Gorgona Park, is a key species for small-scale fisheries in the southern zone of the Colombian Pacific Ocean. Scientific fishing (small-scale methods) established that L. peru growth in Gorgona Park was isometric, being described by the function Pt = 0.0102·Lt 3.0349 . Furthermore, the historical catch record of scientific fisheries in Gorgona Park revealed that the L. peru catch size (mini- mum and average) in the study area has decreased since 1990. The results of this work suggest that it is both necessary to maintain the protected status of L. peru in the marine area of Gorgona Park and to advance the management of the resource in the area of influence.

Arctic charr in Lake Myvatn: The centennial catch record in the light of recent stock estimates

In Lake Myvatn, Arctic charr (Salvelinus alpinus) is economically the most important fish species. It is fast growing fish and its size at maturity is 35–50 cm at the age of 4 to 5 years. Catch statistics that are available for the whole 20th century show considerable long-term variation with the highest catch in the 1920s. The catches after 1970 are about 40% lower than the average from 1930–1969 and the annual catches for the last decade are the lowest. Stock size during the winter fishing season fluctuated considerably between years, with average annual fishing mortality of 83.9%. The Arctic charr population has been monitored annually since 1986, using standard series of gill nets of different mesh sizes. In 1988 one to three-year-old fish were heavily reduced in numbers during the summer months. There are indications of a similar event in 1997. In both years the charr changed its main diet from Cladocera and chironomid midges to three-spined sticklebacks Gasterosteus aculeatus and snails. At the same time its condition deteriorated. The catch in the monitoring fishery in Lake Myvatn correlates with the stock size in the beginning of the following winter fishing season deduced from Leslie's method and can give prospects for the fishery in the successive fishing season. An index of abundance of young charr also correlates with the number of chironomids and cladocerans and also with ducklings that feed on the same food as the charr. Large fluctuations in the Arctic charr population in Lake Myvatn seem to be related to changes in the main food species. The catch records available from Lake Myvatn can to a large extent be used as a measure of changes of the Arctic charr population in the lake for the past century.

Growth rate variability of Pacific saury, Cololabis saira, larvae in the Kuroshio waters

AbstractGrowth rate time series of Pacific saury, Cololabis saira, larvae in the Kuroshio waters were constructed using a previously reported relationship between early life stage growth rates and environmental factors in winter (January to March) 1971–2000, including sea surface temperature, chlorophyll a concentration and copepod density. Pacific saury has been commercially exploited and its stock size shows large fluctuations. It spawns from autumn to spring. Growth and survival in the early life stage have been considered the major factors controlling recruitment fluctuations. The winter spawning cohort showed a fast and stable growth rate during their early stage. Ages of 40 mm juveniles (t40) calculated from growth rate estimations were stable during the 30‐yr period and showed a significant positive correlation to the Pacific Decadal Oscillation index in winter. A negative correlation between the t40 and the catch record of medium size saury (24.0–28.9 cm) was detected but was not significant. Recruitment of the winter spawning cohort is thought to be regulated not only by the duration of the vulnerable larval period but also by other biological factors, i.e. mortality after the larval stage and the abundance of predators.

Testing for a Temperature Effect on an Early Catch Record

In conjunction with early climate records, catch records from pre-industrialfisheries are a potentially valuable sourceof information about the effect of climate on fisheries. This paper describesa test for a temperature effect on an18th century catch record of Icelandic cod. The results of the test, which isbased on a model that incorporatesboth internal population dynamics and a potential temperature effect, supportthe existence of a temperature effect.