Chilean Fisheries Research Articles

Sea Hunters or Sea Farmers? Transitions in Chilean Fisheries

Coastal communities are facing inevitable social-ecological change as aquaculture gains prominence as a major economic industry, and as wild-capture fisheries decline. This paper provides an analysis of this shift through the systematic measurement of indicators of social-ecological resilience in a coastal community on Chiloe Island, Chile, that is undergoing a transformation from small-scale fisheries to wage labor in aquaculture firms. This paper is a presentation of an innovative method to empirically measure indicators of social-ecological resilience, with the intention that the method may be used by other researchers who are attempting to understand a community's capacity for resilience in a variety of settings.

Transcriptome analysis in Concholepas concholepas (Gastropoda, Muricidae): Mining and characterization of new genomic and molecular markers

The marine gastropod Concholepas concholepas, locally known as the “loco”, is the main target species of the benthonic Chilean fisheries. Genetic and genomic tools are necessary to study the genome of this species in order to understand the molecular basis of its development, growth, and other key traits to improve the management strategies and to identify local adaptation to prevent loss of biodiversity. Here, we use pyrosequencing technologies to generate the first transcriptomic database from adult specimens of the loco. After trimming, a total of 140,756 Expressed Sequence Tag sequences were achieved. Clustering and assembly analysis identified 19,219 contigs and 105,435 singleton sequences. BlastN analysis showed a significant identity with Expressed Sequence Tags of different gastropod species available in public databases. Similarly, BlastX results showed that only 895 out of the total 124,654 had significant hits and may represent novel genes for marine gastropods. From this database, simple sequence repeat motifs were also identified and a total of 38 primer pairs were designed and tested to assess their potential as informative markers and to investigate their cross-species amplification in different related gastropod species. This dataset represents the first publicly available 454 data for a marine gastropod endemic to the southeastern Pacific coast, providing a valuable transcriptomic resource for future efforts of gene discovery and development of functional markers in other marine gastropods.

Risk factor analysis for sea lice, Caligus rogercresseyi, levels in farmed salmonids in southern Chile

Sea lice, Caligus rogercresseyi, are ectoparasitic copepods, which severely affect the salmon farming industry in southern Chile, reducing the health status of fish and producing both direct and indirect economic losses. Local farmers have reported increasing infestation levels since 2004, reaching a peak in 2007. In response to this situation, the Chilean Fisheries Service (Sernapesca) developed a surveillance programme; the first step of which consisted of a general survey of salmon farms. This survey included documenting counts of parasite burdens on fish and measurements of several husbandry and environmental factors providing an evaluation of risk factors for the observed infestation levels. The information collected was analysed using a linear mixed model technique, which takes into account the clustered structure of data, decomposing the unexplained variation and assigning it to different aggregation levels of the productive system. Geographical zones, fish species, treatment against sea lice performed 1 month before sampling, stocking density, fish weight and water salinity were the variables significantly associated with sea lice burdens. In contrast, treatments performed 2-3 months before sampling, use of photoperiod in sea cages and water temperature, were not significant. There was significant unexplained variation at all aggregation levels, i.e. sub-zone, fish farm and cage level, with the fish farm level showing the greatest variation.

Viable states for monotone harvest models

This paper deals with the control of discrete-time dynamical, monotone both in the state and in the control, in the presence of state and control monotone constraints. A state x is said to belong to the viability kernel if there exists a trajectory, of states and controls, starting from x and satisfying the constraints. Under monotonicity assumptions, we present upper and lower estimates of the viability kernel. Our motivation comes from harvest models, where some monospecies age class models, as well as specific multi-species models (with so-called technical interactions), exhibit monotonicity properties both in the state and in the control. In this context, constraints represent production and preservation requirements to be satisfied for all time, which also possess monotonicity properties. Our results help delineating domains where a viable management is possible. Numerical applications are given for two Chilean fisheries. We obtain upper bounds for production which are interesting for managers in that they only depend on the model’s parameters, and not on the current stocks.

ITQ’s in Chile: Measuring the Economic Benefits of Reform

In 2001 an individual (operationally transferable) quota system was introduced for all the most important industrial fisheries in Chile. This system was put in place after years of declining stocks and over investment. In this paper we describe this reform and estimate related allocative efficiency benefits for the most important industrial fishery in the country, the southern pelagic fishery. Benefits were estimated using a bioeconomic model estimated using data for the 1985–2004 period. The estimated model was then used to generate simulated scenarios of the evolution of this fishery in a 20 year horizon with and without the ITQ system in place. The benefits of the reform can then be estimated by comparing the fishery’s costs in the scenarios with and without ITQs. This approach allows benefits to be estimated using more realistic counterfactual scenarios than just comparing the fishery before and after the reform. Estimated discounted net benefits reach US $166 million in the period 2001–2020. Fleet size fell from 149 active boats in 2000 to 57 in 2004 as a direct consequence of the reform. Among the interesting features of the Chilean experience is the way the political economy of the reform was facilitated by the prior introduction of de facto individual quotas within the framework of fishery experimental activities. When the authorities closed the southern pelagic fishery because of biological problems between 1997 and 2000, they organized ‘experimental’ fishing expeditions in which participant boats were given the right to fish a certain amount of resources per expedition. This pseudo quota system allowed fishermen to experience directly the benefits of individual quotas and that was instrumental to the political agreement leading to the reform. It is important to note that the Chilean southern industrial pelagic fishery has average catches of over 1.4 million tons a year, making it one of the largest fisheries in the world to be regulated by individual quotas.

Isolation and characterization of microsatellite markers in the southern hake, Merluccius australis

Twenty-six nuclear-encoded microsatellites were isolated from an enriched genomic library of southern hake, Merluccius australis, and characterized in 30 individuals. The microsatellites include 18 dinucleotide repeats, seven trinucleotide repeats (two imperfect), and one pentanucleotide repeat. Southern hake support important industrial and artisanal fisheries in Chile, Argentina, and New Zealand.

What factors affect the decision making process when setting TACs?: The case of Chilean fisheries

Abstract Although failures and successes in fisheries management are related to decision making processes, these are rarely analyzed in detail and even less often following quantitative or semi-quantitative approaches. Herein, we study the decision making process for Chile's most important fisheries using a binary decision model. This model evaluates the probability that an annual total allowable catch (TAC) will or will not be modified by the National Fisheries Council (NFC) based on biological, economic, and social factors. We also analyze some aspects of individual voting, particularly whether the members vote against or abstain from voting on the proposed TAC and if they prioritize resource conservation objectives. Our results indicate that the risk of over exploitation for many important stocks in Chile is aggravated by failures at the decision making level: the scientifically recommended TACs for those fisheries that generate higher levels of employment and have greater economic value are normally increased. This analysis shows that the NFC has clearly prioritized short-term economic and social objectives over resource conservation goals. We discuss the need to adjust the composition and functioning of the NFC in order to ensure long-term sustainability of the fisheries.

Direct observation of Chilean hake ( Merluccius gayi gayi) behaviour in response to trawling in a South Central Chilean fishery

The behaviour of Chilean hake ( Merluccius gayi gayi) in a bottom trawl was observed with an underwater camera positioned in the trawl mouth and in the front of the codend extension. Significant differences were observed in the fish behaviour in the two sections, demonstrating that this species is more active in the mouth of the net. The fish activity was lower in the trawl extension, where the fish were merely carried by the flow into the net.

Morphological characteristics of five bycatch sharks caught by southern Chilean demersal longline fisheries

The by-catch of sharks in artisanal demersal pink cusk-eel (Genypterus blacodes) and yellownose skate (Dipturus chilensis) fisheries is frequent within their fishing effort. Nevertheless, there is no registry of landings, which could help to control this problem. This is particularly evident for endemic species, which includes most coastal and deep water Chilean sharks. The main systematic characteristic of these Chondrichthyan species is the external morphology of the neurocraneum. The form and arrangement of the teeth and dermal denticles allow specific differences to be identified. The objective of this paper is to contribute to the biology and systematic knowledge of demersal shark species, teeth and dermal denticle morphology and neurocraneum morphometrics of two species of Scyliorhinids, the redspotted catshark (Schroederichthys chilensis) and the dusky catshark (Halaelurus canescens), as well as three Squaliforms, the granular dogfish (Centroscyllium granulatum), the birdbeak dogfish (Deania calcea) and the spiny dogfish (Squalus acanthias).

ITQs under illegal fishing: An application to the red shrimp fishery in Chile

Abstract We study an individual transferable quota system with imperfect enforcement. We apply a model of individual fisherman behavior to the red shrimp (Pleuroncodes monodon) fishery in central-southern Chile. Simulation results suggest that illegal fishing could generate a 21% increase in fishing effort, resulting in a 13% increase in catch and a 2% lower quota price in comparison with the results of a system that operates under perfect compliance. The results are sensitive to changes in the level of fish abundance, total allowable catch, and the design of enforcement to induce compliance.

Reproductive cycle, size at first maturation and fecundity in the golden ling, Genypterus blacodes, in Chile

Reproductive aspects of the golden ling, Genypterus blacodes, from the southern Chilean fishery are presented. Gonad samples were obtained from commercially caught fish between September 1999 and October 2000. Stage of sexual maturity, gonadosomatic index (GSI), and size of females at 50% maturation determined by logistic methods and by plotting the mean GSI by total length, are presented for both years. Batch fecundity was calculated from subsampling mature ovaries containing oocytes in advanced stages of maturity. Changes in GSI and monthly diameters of oocytes showed that ling had a spawning season which extended between August and November. The sizes at first maturity in 1999 and 2000 were 86.6 and 84.8 cm total length (TL), respectively, using the logistic model, and 84 cm for both years using the mean GSI‐size plotting method. The mean batch fecundity was 333 330 oocytes per individual for fish sized 85–120 cm TL. Fecundity increased with increasing weight and total length.

Long-term changes in the mean trophic level of Central Chile fishery landings

We explore long-term changes in the mean trophic level ( TLm ) of Central Chile fishery landings, using a 21 years data series (1979-1999) of official landings (Chilean Fisheries Service) of 16 species that comprise about 95% of total landing, and their corresponding trophic level estimated using gut content analysis and a trophic model of the Central Chile marine ecosystem. Because total landings off Central Chile have been strongly influenced by landings of horse mackerel ( Trachurus symmetricus ), which is a trans-zonal fishery resource (sensu FAO), and the periodic occurrence of El Nino Southern Oscillation (ENSO) events in the study area, we explore changes in TLm both excluding landings of horse mackerel and excluding landings in ENSO years. When landings of horse mackerel are excluded, a significant decline in TLm is found, at a rate of 0.175 per decade, which is higher than the global rate of 0.10 estimated by Pauly et al. (1998). Fisheries in Central Chile seem to have been fishing down the food web as the result of fishery-induced changes, since ENSO events do not seem to have induced a significant effect in this trend. Therefore, we suggest that landings of horse mackerel have masked the fishing down the food web process in local fisheries.

Total allowable catch for managing squat lobster fishery using stochastic nonlinear programming

The authors’ work on lobster fishery in Chile is summarized in this paper. The paper presents the formulation and algorithmic resolution of a two-stage stochastic nonlinear programming model with recourse. The proposed model considers a long-term planning horizon and specifically allows an optimal total allowable catch quota to be obtained for the first planning period. This model takes into account biomass dynamics, the conditions guaranteeing sustained species management and uncertain parameters such as growth rate and species carrying capacity. These parameters are explicitly incorporated via a discrete random variable (scenarios). The proposed model is solved by Lagrangian decomposition using the algebraic modeling software AMPL, in combination with the solver MINOS to solve the nonlinear models resulting from the scenario decomposition. The article also presents the results obtained with this methodology and the conclusions drawn from the work.

Facilitation of Collaborative Management: Reflections From Practice

Collaborative management of natural resources requires that multiple stakeholders come together to negotiate agreements. Who is a stakeholder, what is the boundary and the definition of an issue, and who has legitimacy to convene are interrelated, systemic questions. To address this challenge, this paper provides a conceptual framework with nine Contextual Dimensions. A workshop on collaborative and conflict management of the fishery in Chile, designed and facilitated by the authors, serves as a case study where multiple stakeholders came together to vision desirable futures and explored organizational linkages that could accommodate the different agendas. The workshop is analyzed through a conceptual framework and some conclusions are drawn on the value of experiential learning and on the importance of the iterative consultations that must precede such collaborative management events.

643 The influence of type 1 pyrethroids: Cypermethrin and deltamethrin on algae, crustaceans and rotifer

The pesticides used by the salmon industry to treat sea lice, are applied in situ via a bath solution and are subsequently discharged into the surrounding medium. The effects of cypermethrin, deltamethrin, azamethiphos and hydrogen peroxide were assessed on the performance of Metacarcinus edwardsii larvae, an important crab for Chilean fishery. All larvae were dead or dying after 30 min of exposure to cypermethrin and after 40 min to deltamethrin at concentrations 100 and 20 times lower (0.15 and 0.1 μg L−1, respectively) than the concentrations and exposure times recommended by the manufacturers (CRM) to treat sea lice. Azamethiphos affected all larvae at a concentration 10 times lower than CRM. Hydrogen peroxide had the lowest detrimental effects, but at the CRM, 100% of the larvae were affected. Sub-lethal effects, i.e prolonged developmental time, were observed at concentrations lower than CRM. Repeated exposure to azamethiphos (0.0625–0.5 μg L−1) and hydrogen peroxide (188–1500 mg L−1) had effects on survival. In conclusion, the pesticides used against parasitic copepod tested here, negatively affect non-target crustacean larvae. Due to the product’s characteristics, the lethal effects of the pyrethroids probably are restricted to the time and area of application, while the action of azamethiphos may extend to a wider area. Current data are insufficient to accurately dimension the effects of these compounds in the field. More research is required to evaluate the consequences of prolonged developmental times and/or reduction in appendage mobility, so as the effects of these compounds on the pelagic and benthic communities.

Overview of cephalopod fisheries in Chilean waters

This paper describes the history of cephalopod fisheries in Chile over the past 40 years. Continuous monitoring of three species was undertaken between 1978 and 1999: Loligo gahi, Dosidicus gigas and Octopus mimus. Total cephalopod catches increased from 69 tonnes in 1978 (0.13% total mollusc catch) to 3503 tonnes in 1996 (3.64%). A maximum haul of 15,169 tonnes was taken in 1992 (11.27% total mollusc catch). Small-scale fisheries accounted for the majority of cephalopod captures and industrial catches were rare. L. gahi is caught year-round mainly in the south of Chile, with maximum catches in summer and autumn. Catches of D. gigas are also year-round, mainly concentrated in central Chile. O. mimus has been fished since 1978, although recorded as Octopus vulgaris until the 1990s. The O. mimus fishery is located on the north coast of Chile, and catches are made for the most of the year. Octopus has been landed in the south of Chile since 1991, and is considered as O. mimus in capture statistics despite the fact that several species are represented, including Enteroctopus megalocyathus.

Hydrographic conditions off northern Chile during the 1996–1998 La Niña and El Niño events

The evolution of oceanographic conditions in the upwelling region off northern Chile (18°–24°S) between 1996 and 1998 (including the 1997–1998 El Niño) is presented using hydrographic measurements acquired on quarterly cruises of the Chilean Fisheries Institute, with sea surface temperature (SST), sea level, and wind speeds from Arica (18.5°S), Iquique (20.5°S), and Antofagasta (23.5°S) and a time series of vertical temperature profiles off Iquique. Spatial patterns of sea surface temperature and salinity from May 1996 to March 1997 followed a normal seasonal progression, though conditions were anomalously cool and fresh. Starting in March 1997, positive anomalies in sea level and sea surface temperature propagated along the South American coast to 37°S. Maximum sea level anomalies occurred in two peaks in May–July 1997 and October 1997 to February 1998, separated by a relaxation period. Maximum anomalies (2°C and 0.1 practical salinity units (psu)) extended to 400 m in December 1997 within 50 km of the coast. March 1998 presented the largest surface anomalies (>4°C and 0.6 psu). Strong poleward flow (20–35 cm s−1) occurred to 400 m or deeper during both sea level maxima and weaker (10 cm s−1) equatorward flow followed each peak. By May 1998, SST had returned to the climatological mean, and flow was equatorward next to the coast. However, offshore salinity remained anomalously high owing to a tongue of subtropical water extending southeast along the Peruvian coast. Conditions off northern Chile returned to normal between August and December 1998. The timing of the anomalies suggests a connection to equatorial waves. The progression of the 1997–1998 El Niño was very similar to that of 1982–1983, though with different timing with respect to seasons.

Genetic variation and population structure in the marine snail Chorus giganteus (Gastropod: Muricidae), an overexploited endemic resource from Chile

The endemic marine gastropod Chorus giganteus represents a significant part of the benthic biomass subject to heavy exploitation by artisanal fisheries in Chile. Overexploitation has restricted its formerly wide distribution to few sites, and this study deals with the electrophoretic characterisation of three populations from the two main fishing grounds in the south coast of Chile (37–39°S). While frequency of polymorphic loci is high (41–50%), the observed heterozygosity is low (between 0.028 and 0.040) though within the range for molluscs. Heterogeneity in allelic frequencies at six polymorphic loci suggests potential for population substructuring. All these loci showed significant heterozygote deficits. The calculated number of migrants per generation ( N e m=4.75), based on a Wright’s F ST mean value of 0.05, accounts for low gene flow among populations in line with breeding behaviour (locally restricted). These preliminary results set a baseline for further evaluation of the intraspecific genetic diversity of an overexploited mollusc with low larval dispersal ability, and hence limited ability for colonisation. Since basic culture techniques are not yet available, genetic monitoring of this species throughout its entire distribution should be promoted for proper management and/or conservation of the species gene pool, in addition to current regulations aimed at restricting further exploitation.

A review of the world marine gastropod fishery: evolution of catches, management and the Chilean experience

Marine mollusks are among the most importantinvertebrate fisheries in the world. The mainclasses of mollusk fished are Cephalopoda,Bivalvia and Gastropoda. Marine gastropodsrepresent approximately 2% of the mollusksfished in the world. Several species ofgastropods, such as Haliotis spp., Strombus spp., Busycon spp. and Concholepas concholepas, have high economicvalue in international markets and playimportant social roles in small-scale artisanalfisheries. In the past 25 years wild-stockcatches of marine gastropods have increasedfrom 75,000 mt in 1979 to 103,000 mt in 1996.During the same period the countries involvedin gastropod landings rose from 23 to 47.Gastropods are fished mainly in: (1) theAmerican continent, dominated by the extractionof the muricid ``loco'', C. concholepas, inChile and Peru; strombid conchs, Strombusspp., in the Caribbean, and abalone, Haliotis spp., in California and the west coastof the Baja California peninsula; (2) Asia andOceania, with the dominate abalone fishery,mainly in Australia and New Zealand, and thehorned turban snail, Turbo truncatus, inJapan and Korea; (3) in Africa and Europe, thedominate species extracted are Haliotismidae, heavily fished in South Africa, and thecommon periwinkle, Littorina littorea,and the whelk Buccinum undatum, which areextracted in Europe. This review summarizes the fishery of abalonespecies in California and the west coast of theBaja California peninsula. We highlightoverfishing situations and the utilization ofadaptive management tools, such as those inoperation in Baja California, where small-scalefisher associations (cooperatives) havereceived exclusive access rights to abaloneextraction within specific fishing zones, since1936. We also review the abalone fishery inAustralia, and the use of IndividualTransferable Quotas (ITQs) and Total AllowableCommercial Catches (TACC), which have been inuse since the mid-1980's. We describe thegastropod fisheries in Chile, mainly C. concholepas, highlighting their economic andsocial importance. We provide information onthe evolution of catches and exports anddiscuss the development of novel managementadaptive tools, such as the implementation ofthe Benthic Regime for Extraction andProcessing (BREP), the introduction ofNon-Transferable Individual Quotas (NTIQs) andterritorial users rights for benthic fisheries,such as the Management and Exploitation Areas(MEAS). Finally, we present and discuss thenecessary steps for the sustainable managementof marine gastropods and other benthic resources.

New regulations in Chilean Fisheries and Aquaculture: ITQ’s and Territorial Users Rights

The large industrial fishery development that turn Chile into the third fishing nation in the world is described, and recent regulatory innovations introduced by new Fishery and Aquaculture legislation are reviewed. In addition to classical Fishery management tools, different types of limited entry systems are now defined in the law and applicable to Chilean fisherie. These for the first time include allocation of resources in the form of Individual Fishing Quotas and Individual Transferable Quotas (IFQs and ITQs). Territorial User’s Rights in Fisheries (TURF’s) were incorporated in the law to enhance self-regulatory practices among artisanal fishermen. Among them, the Areas for Management and Exploitation for Benthic Resources (AME) represent an associative assignment of TURFs. Large-scale zoning is used to re-define Aquaculture Grants and to ritualise the conflicts between Artisanal and Industrial fishermen by establishing the Artisanal Reserve in which small-scale coastal fishermen have Priority Access. Performance of the new management instruments are documented with case studies, for the following fisheries: the loco ( Concholepas concholepas) a carnivorous snail, keyhole limpets (Fissurella spp.), langostino or squat lobster ( Cervimunida johni), Black hake ( Dissostichus eleginoides) and the Yellow prawn ( Pleuroncodes monodon).