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Non-compliance with fishing regulations is a widespread phenomenon in fisheries worldwide, jeopardizing the recovery of stocks and ecosystem services. There is an urgent need to fill the gaps in our understanding of the scale and nature of illegal fishing in artisanal fisheries, balancing the advances made in industrial fisheries. We explored patterns of fisher compliance with the existing minimum legal size (MLS) regulation in the small-scale benthic fisheries of central Chile. We focus on two of the most conspicuous species (loco Concholepas concholepas and keyhole limpets Fissurella spp.) and comparing two management regimes: management areas (MAs; local name for territorial use rights for fisheries) and open access areas (OAAs; no spatial entry restrictions). We also evaluated the effect of the spatial distribution of MAs, which determines the availability of OAAs on compliance. For both species, we measured the size of individuals in the catch in two consecutive years. We developed an index that accounts for the availability of open access areas per fisher. We found that a) the number of undersized individuals in the catch in OAAs is enormous, b) management regime influences both the median size and fraction of the undersized catch, and c) as the availability of OAAs per fisher decreases, illegal fishing increases, demonstrating the need to manage the levels of effort displacement in designing area-based instruments for management and conservation. Our findings also highlight the need to a) analyze the benefits of area-based instruments at the seascape scale, and b) develop and adapt instruments to prevent illegal fishing. more...

9 pages, 4 figures, 1 table, supplementary data https://doi.org/10.1016/j.jenvman.2018.09.034, It is crucial that societies are informed on the risks of impoverished ecosystem health for their well-being. For this purpose, Ecological Integrity (EI) is a useful concept that seeks to capture the complex nature of ecosystems and their interaction with social welfare. But the challenge remains to measure EI and translate scientific terminology into operational language to inform society. We propose an approach that simplifies marine ecosystem complexity by applying scientific knowledge to identify which components reflect the state or state change of ecosystems. It follows a bottom-up structure that identifies, based on expert knowledge, biological components related with past and present changing conditions. It is structured in 5 stages that interact in an adaptive way: stage 1, in situ observations suggest changes could be happening; stage 2 explores available data that represent EI; stage 3, experts' workshops target the identification of the minimum set of variables needed to define EI, or the risk of losing EI; an optative stage 4, where deviance from EI, or risk of deviance, is statistically assessed; stage 5, findings are communicated to society. We demonstrate the framework effectiveness in three case studies, including a data poor situation, an area where lack of reference sites hampers the identification of historical changes, and an area where diffuse sources of stress make it difficult to identify simple relationships with of ecological responses. The future challenge is to operationalise the approach and trigger desirable society actions to strengthen a social-nature link, Funding for JH was provided by NIWA Coasts and Oceans Centre (MBIE CORE). SdJ was funded by H2020-Marie Skłodowska-Curie Action MSCA-IF-2016 [Project ID: 743545]. MDS was funded by FONDECYT 1130580 grant and ICM grant CCM – RC130004 from Ministerio de Economía, Fomento y Turismo (Chilean Government) more...

Many artisanal fisheries lack of conventional scientific data for stock assessment and decision making, which might explain the overexploitation and collapse of many small-scale fish stocks. Fishers' perception has a great potential to be an alternative source of information as it is present in every fishery, is inexpensive and allows analysis at large spatial scales. However, fishers' perception is influenced by psychological factors that can generate bias. This study compares fishers' perception and direct assessment of current and historical abundances of two benthic species that are targeted in the artisanal fishery of Central Chile (the loco and the keyhole limpet), in order to assess the value of the method for artisanal fisheries. The analysis also considered different management regimes (open access areas and areas with territorial rights) and two periods of time (approximately 15 years apart) to determine the (a) the consistency of fishers' perception for assessment of current abundance and (b) the potential use for retrospective assessment. We also compared official landing reports with direct assessments in order to assess the reliability of fisheries data. Fishers' perception of loco abundance generally agreed with direct assessment in fishing villages, management regimes and periods of time. In the case of the keyhole limpet, fishers perceived abundances higher than those registered in direct assessments. The different patterns observed between resources can be related to the relative importance of each fishery. Fishers were not accurate in recalling past abundances retrospectively and official reports showed dramatic mismatches with direct assessment in catch abundance and composition. Fishers' perception is a potential source of information to assess the current abundance of targeted species. However, it requires case by case investigation and evaluation before it can be applied and the information properly integrated in fisheries management practices. more...

12 pages, 5 figures, 1 table, We assessed the gaps between current and “model mapping routines”, which represent a benchmark for mapping marine ecosystem services (ESs). Model mapping routines comprised 17 selected variables and their best-rated alternatives depending on the mapping purpose, namely, marine spatial planning, environmental impact assessment, vulnerability and risk analysis, marine protected areas management, payments for ecosystem services, and natural resources management. We conducted a systematic search of articles (n = 64) from which information on the 17 variables and their alternatives was retrieved. We assessed gaps using similarity matrices, according to the co-occurrence index. The largest gaps (as measured by average distances >0.5 between actual and best options) occurred in articles reporting natural resources management as purpose, whereas the smallest were related to marine protected areas management and payments for ecosystem services. The gaps were due to departures in different individual variables. For example, in the case of marine spatial planning the omission of tradeoffs, scenario analysis, multiple scales, and threshold analyses explained the gap, whereas in vulnerability and risk assessment the omission of thresholds, the lack of consistency of the indicators used, and the absence of a definition of ESs explained the gap. We trust that this study will help to recognize that ESs mapping studies should be guided by the purpose of a given intervention rather than by the technical capacities and disciplines of the researchers, if the ESs approach expects to reach a real impact into public policies, LN, G.C, X.V and F.B were funded by CONICYT Chile through FONDAP Grant 15150003; MDS was funded by Fondecyt 1130580. MDS and MF received funding from Fondecyt 1171603 grants and ICM grant CCM – RC130004 from Ministerio de Economía, Fomento y Turismo (Chilean Government). SV acknowledges the financial support of the European COST Action “Ocean Governance for Sustainability - challenges, options and the role of science”, the ICES Science Fund Project “Social Transformations of Marine Social-Ecological Systems”, and the CYTED program for the ECOMAR Network more...

Tegula tridentata, is a common herbivore gastropod inhabiting the subtidal Lessonia trabeculata kelp forest, which tends to show higher densities after kelp harvesting. We investigated if harvested kelp beds may harbor higher densities of herbivore invertebrates, and the underlying mechanisms. Thus, we evaluated if the exudates of L. trabeculata change the seawater levels of soluble phenols, known to have a deterrent effect against the feeding behavior of some herbivore invertebrates. Finally we investigated whether the increase in T. tridentata densities in harvested kelp grounds could be related to a decrease in the seawater levels of soluble phenols. Our results showed that the density of invertebrate herbivores increased up to 32% in harvested kelp grounds. We provide the first estimate of the rate of phenolic exudation by L. trabeculata, and we demonstrate that T. tridentata changes its food dependent movement in the presence of exudates with synthetic phloroglucinol. We suggest that the recovery of harvested kelp ecosystems can be jeopardized by increased herbivory triggered by water-borne changes in the levels of herbivore deterrent compounds. more...

14 páginas, 8 figuras., Estuaries are used as nursery grounds by numerous marine species despite being usually subject to strong anthropogenic disturbances. Abundances of marine recruits (fish and crustacean decapods) and their main prey (mysids) were monitored by monthly sampling, from June 1997 to February 2009, in the lower reaches of the Guadalquivir estuary (SW Spain). During that period, unusually high and persistent turbidity events (HPTEs) were observed twice. Both HPTEs started with strong and sudden freshwater discharges after relatively long periods of very low freshwater inflow. Data from this time-series were used to test the hypothesis that HPTEs may negatively impact the nursery function of estuaries either by decreasing prey availability or by decreasing survival/arrival of marine recruits. During HPTEs, the commonest mysid (Mesopodopsis slabberi), a key species in the estuarine food web, showed a significant decrease in abundance. Likewise, some marine recruits that prey on M. slabberi and whose peaks of abundance within the estuary occur in summer–autumn (Engraulis encrasicolus and Pomadasys incisus) were less abundant during HPTEs. It is also suggested that HPTEs might have triggered a shift in the distribution of the most euryhaline prey (Neomysis integer) and predator (Dicentrarchus punctatus and Crangon crangon) species, towards more saline waters. This could have contributed to an increase in the inter-specific competition (for food/habitat) within the estuarine nursery area. The results discussed in this study call attention to the need to reduce as much as possible the anthropogenic pressures that may stimulate the occurrence of high and persistent turbidity events (HPTEs) in order to preserve the nursery function of temperate estuaries., The study was supported by the Spanish MCYT projectREN2000-0822 MAR, the Environmental and Fishery Agency of Autonomous Andalusia Government (“Consejería de Medio Ambiente” and “Consejería de Agricultura y Pesca: Junta de Andalucía”) and EU Fishery Grant. more...