Resumen. Los tambores y roncadores (Sciaenidae) son parte importante de la composición específica de las capturas costeras en el Golfo de California, México. Dentro de este grupo de especies, la curvina rayada (Cynoscion reticulatus) destaca por su alto potencial pesquero, gran demanda y debido a que ha incrementado su valor de mercado. La curvina rayada ha estado bajo constante presión pesquera durante los últimos 20 años. Sin embargo, se necesita contar con información biológica actual o puntos de referencia que permitan establecer medidas de manejo pesquero. Por tanto, el objetivo del presente estudio fue estimar la longitud estándar media de madurez sexual (LE 50 ) utilizando varios modelos para sugerir una talla mínima de captura (TMC) de C. reticulatus en la costa sur de Sinaloa. Para esto, se realizaron muestreos mensuales en las descargas de la flota costera desde diciembre de 2020 hasta diciembre de 2021 en la costa sur de Sinaloa. La LE 50 se evaluó con base en 3 modelos candidatos (Gompertz, Lysack y White) a través de un enfoque binomial. Los intervalos de confianza para la LE 50 se estimaron utilizando perfiles y contornos de verosimilitud, y se utilizó el criterio de información de Akaike (CIA) para seleccionar el mejor modelo. Se examinaron un total de 284 individuos, de los cuales 131 se utilizaron en el análisis. El modelo de White fue el más adecuado; sin embargo, con base en los pesos de CIA, los 3 modelos mostraron un rendimiento similar, por lo que la LE50 (24.48 cm; IC 95% 12.9-36.0 cm) se estimó como el promedio de estos. Por último, como medida de manejo, proponemos una TMC bajo un enfoque precautorio de 36 cm LE para C. reticulatus en la costa sur de Sinaloa.

Abstract. Drums and croakers (Sciaenidae) are important to the species composition of coastal catches in the Gulf of California, Mexico. Among these species, the striped corvina (Cynoscion reticulatus) stands out because of its high fishery potential, high demand, and increased market value. The striped croaker has been under constant fishing pressure over the past 20 years. Still, there needs to be current biological information or reference points to allow the establishment of management measures for fisheries. The objective of the present study was to estimate the mean standard length at sexual maturity (SL 50 ) of females using various models and to suggest a minimum catch size (MCS) for C. reticulatus off the southern coast of Sinaloa. Monthly samplings of coastal fishery landings were done from December 2020 to December 2021 on the south coast of Sinaloa. The SL 50 was evaluated based on 3 candidate models (Gompertz, Lysack, and White) through a binomial approach. Confidence intervals for SL 50 were estimated using likelihood profiles and contours, and Akaike’s information criterion (AIC) was used to select the best model. A total of 284 individuals were examined, of which 131 were used in calculations. White’s model was the most adequate; however, based on AIC weights, all 3 models performed similarly, and SL 50 (24.48 cm; C.I. 95% 12.9-70 36.0 cm) was estimated as their average. As a management measure, we propose a precautionary MCS of 36 cm SL for C. reticulatus off southern Sinaloa.

Abstract Introduction: Semaprochilodus laticeps is a freshwater fish species native to the Orinoco Basin that is exploited in Colombia at two different stages of its life cycle: fry (for the ornamental trade) and adults (for the consumer market). This double exploitation of juveniles and adults raises concerns about the population stability of the species. Objective: To evaluate the sustainability of the exploitation of the species in these two life stages. Methods: 1 277 specimens of S. laticeps were sampled between June and December 2017. Population parameters were estimated from length-frequency data using ELEFAN 1 routine of the FISAT II package. Length at first maturity (Lm) and length at maximum yield (Lopt) were determined using the Froese and Binohlan equations. Virtual population analysis was performed based on Jones length cohort analysis. Results: Population parameters were as follows: K = 0.75, L∞ = 53.1 cm LE, Z = 2.92 yr-1, M = 1.24 yr-1 and F = 1.68. Lm was estimated to be 29.6 cm SL and Lopt at 33.4 cm SL. Of note, 96.3 % of the fish caught in the consumer fishery exceeded Lm and 80 % exceeded Lopt. The results of the virtual population analysis suggested that a very low proportion (0.85 %) of the population was caught as fry, possibly due to natural mortality. Conclusions: Based on the results, as no indicators of overexploitation were identified, it is recommended to continue with the dual use of S. laticeps. It is recommended to maintain the existing conservation measures, such as the closed season during the reproductive period, to ensure sustainable fishery exploitation. The results obtained can serve as a reference to analyze the situation of other species currently fished for both the ornamental (fry) and food (adult) markets.

Resumen Introducción: Semaprochilodus laticeps es una especie de pez de agua dulce originaria de la cuenca del Orinoco, explotada en Colombia en dos etapas distintas de su ciclo de vida: alevín (para el comercio ornamental) y adulto (para el mercado de consumo). Esta doble explotación de alevines y adultos genera preocupación sobre la estabilidad poblacional de la especie. Objetivo: Evaluar la sostenibilidad de la explotación de la especie en estas dos etapas de vida. Método: Entre junio y diciembre de 2017 se muestrearon 1 277 ejemplares de S. laticeps. Los parámetros poblacionales se estimaron utilizando datos de frecuencia de tallas con la rutina ELEFAN 1 del paquete FISAT II. La longitud de primera madurez (Lm) y la de máximo rendimiento (Lopt) se determinaron mediante ecuaciones de Froese y Binohlan. El análisis de la población virtual se realizó basándose en el análisis de cohorte de longitud de Jones. Resultados: Los parámetros poblacionales fueron los siguientes: K = 0.75, L∞ = 53.1 cm LE, Z = 2.92 año-1, M = 1.24 año-1 y F = 1.68. Lm se estimó en 29.6 cm SL y Lopt en 33.4 cm SL. En particular, el 96.3 % del pescado capturado en la pesquería de consumo superó Lm y el 80 % superó Lopt. El análisis de la población virtual sugirió que una fracción muy baja (0.85 %) de la población fue capturada como alevines, posiblemente atribuible a la mortalidad natural. Conclusiones: Con base en los hallazgos, al no identificarse indicadores de sobreexplotación, se recomienda continuar con el doble uso de S. laticeps. Se recomienda mantener las medidas de protección existentes, así como una veda durante el período reproductivo, para garantizar una explotación pesquera sostenible. Los resultados obtenidos pueden servir como referencia para analizar la situación de otras especies actualmente capturadas para el mercado tanto ornamental como de consumo.

Research that directs the way stakeholders act and how they collaborate is essential when addressing complex environmental challenges in the field of sustainability science. For example, researchers attempting to manage Prosopis invasions through biological control in South Africa have historically faced challenges from stakeholders. In this study we illustrate the importance of stakeholder engagement and social learning by outlining the collaborative efforts of various stakeholders to promote effective, integrative and sustainable management of Prosopis invasions in the Northern Cape, South Africa. Through a community of practice approach, stakeholders worked together over the past half-decade in an attempt to develop a National Strategy for Prosopis management and improve its control. This strategy aimed not only to emphasise the need for integration of biomass use (aimed at offsetting the costs of mechanical clearing and necessary herbicide use) but also to underscore the significance of biocontrol alongside other management approaches. Stakeholders also identified that adequate farm-scale planning is necessary to provide a sense of purpose and assist in monitoring of progress. We worked alongside land managers and experts to develop such plans. The engagement of local champions played a crucial role in facilitating collaboration and learning among stakeholders, emphasising the significance of inclusive approaches in addressing complex sustainability challenges. In addition, we gained an understanding of how to develop the community of practice to enhance collaboration that ensures the implementation of plans to better manage Prosopis. Our findings underscore the necessity of meaningful stakeholder engagement and collaboration in effective invasive species management. By promoting understanding and involvement of diverse stakeholders, initiatives can have a greater impact in addressing broader sustainability issues. SIGNIFICANCE: Our findings highlight the fundamental role of stakeholder collaboration in addressing environmental challenges (e.g. biological invasions), promoting sustainability and fostering social learning. Collaboration facilitates exchange of knowledge, promotes social learning and allows stakeholders to make informed decisions when addressing sustainability issues. Collaborative approaches promote the effectiveness of a community of practice in managing Prosopis invasions in South Africa. Local champions played a pivotal role in facilitating collaboration, bridging communication gaps and promoting inclusive approaches. Sustained stakeholder engagement, transdisciplinary collaborations, effective biological control and market development for biomass products will be essential to improve the sustainable management Prosopis.

ABSTRACT. Oreochromis niloticus is the most important aquacultural species worldwide. Several countries are interested in repopulating natural or artificial reservoirs with the fry of tilapia (Oreochromis sp.) to develop new fisheries or to enhance the existing ones. However, as tilapia is considered an invasive species, it is essential to check the existence of the species in the place before releasing any fry. Characterization of tilapia species with meristic is unreliable because of existing morphological similarities among species. In this work, the composition of the tilapia species of Laguna El Mastranzo (LEM), Nayarit, Mexico, was explored for the first time through a molecular method using the mitochondrial DNA control region. Three tilapia species (Oreochromis niloticus, O. aureus, and O. urolepis) were found in LEM, and it was confirmed that the two commercial strains (Aquamol and Spring) intended for repopulation were O. niloticus. Seven haplotypes of mitochondrial DNA control region sequences were obtained: three in LEM, three in Aquamol, and one in Spring strains. Before repopulating any reservoir, a molecular verification strategy is recommended to avoid spreading the species. The results of this work represent a glimpse into the genetic material of LEM, Nayarit, Mexico.

ABSTRACT Chile has a relatively long history of monitoring and managing large-scale commercial fish stocks. However, many other small-scale fisheries, particularly those operating in estuaries, usually lack basic fisheries and biological information. International experience indicates that a monitoring system designed for large-scale stocks cannot simply be resized to address the complexity, relatively low total economic value, and the large number of actors and supply chains in small-scale fisheries. This article proposes a strategy to monitor data-poor fisheries operating in estuaries. The striped mullet (Mugil cephalus), locally known as "lisa", in the Rapel River, central Chile, was selected to establish a pilot monitoring program for small-scale fish resources. From May 2022 to May 2023, fisheries information, including fleet description, catch and effort data, and fish biological attributes such as length and weight, were collected and described for the first time in the region. Drawing insights from this case study, we propose developing a generic monitoring system tailored specifically for monitoring fish stocks in estuaries. This conceptualization is based on: i) change agents, who are individuals trained to work with both the social and biological dimensions of each coastal fish stock; ii) experienced fisheries scientists outside government agencies; and iii) local fishers’ knowledge to provide constant feedback for adapting temporal and spatial scales for monitoring. This monitoring scheme is cost-effective and can be efficiently replicated in other estuarine fisheries in Chile.

ABSTRACT Food availability is defined as the sufficient quantity of food of adequate quality and culturally acceptable for the population of a country in a given period. In the case of the cities of the North Coast of the Uruguay River, there is little availability in terms of local fishing. The objectives of this research were to analyze the causes of this scarce availability through the opinion of the artisanal fishermen of the region, and the referring institutions. Semi-structured interviews were conducted with artisanal fishermen and institutional references in the region, as well as a representative of the private sector. The inability of fishermen to dedicate themselves exclusively to the activity; the export destination that has the majority of the region's catches; the low consumption at national level and the scarce demand of the cities for river fish, were some of the enunciated causes.

RESUMEN La disponibilidad de alimentos se define como la cantidad suficiente de alimentos de calidad adecuada y culturalmente aceptables para la población de un país en un período determinado. En el caso de las ciudades del Litoral Norte del Río Uruguay, se observa una escasa disponibilidad en materia de pesca local. Los objetivos de esta investigación fueron analizar las causas de esta escasa disponibilidad a través de la opinión de los y las pescadores artesanales de la región, y las instituciones referentes. Se realizaron entrevistas semi estructuradas a pescadores artesanales y referentes institucionales de la región, así como a un representante del sector privado. La imposibilidad de los pescadores para dedicarse exclusivamente a la actividad; el destino exportador que tiene la mayoría de las capturas de la región; el bajo consumo a nivel nacional y la escasa demanda de las ciudades por pescado de río, fueron algunas de las causas enunciadas.

Resumen El objetivo fue estimar el impacto que tendrán los precios de garantía y de mercado del maíz blanco sobre el impuesto predial rústico para el 2023. Se utilizaron datos del Sistema de Información Agropecuaria y Pesquera (SIAP, 2022). El método utilizado es el deductivo y la investigación es de tipo explicativa y descriptiva. Los resultados indican que otorgar precios de garantía solo a productores de hasta 15 hectáreas y, excluir a los que sembraron más allá de esa superficie, afectará la recaudación. Entre los hallazgos se tiene la importancia de la siembra de maíz blanco para financiar obras públicas en comunidades rurales. Su originalidad radica relacionar la producción del maíz con el principal impuesto local de los gobiernos municipales: el predial. Por limitaciones no se pudo tener acceso al mecanismo de recaudación descentralizado, a partir de junio del presente año, para administrar dicho tributo.

Abstract The objective was to estimate the impact that the guarantee and market prices of white corn will have on the rustic property tax for 2023. Data from the Agricultural and Fisheries Information System (SIAP, 2022) were used. The method used is deductive and the research is explanatory and descriptive. The results indicate that granting guaranteed prices to producers of up to 15 hectares and excluding those who sowed beyond that area, will affect the collection. Among the findings is the importance of planting white corn to finance public works in rural communities. Its originality lies in the studied relationship production of corn with the main local tax of municipal governments: the predial. Due to limitations, it was impossible to have access to the decentralized collection mechanism, as of June of this year, to administer said tax.

ABSTRACT This study examines the distributional behavior of the anchovy (Engraulis ringens) in the area between latitudes 06° 00´ and 11° 59´ S during four research activities conducted by Imarpe from February to June 2022. This area was initially restricted in the first fishing season due to the high presence of juvenile specimens. The purpose was to observe the redistribution of anchovy to propose management measures for fisheries sustainability. During activities 1 and 2, a high concentration and abundance of anchovy were observed, while in activities 3 and 4, the anchovy dispersed, migrating towards areas away from the coast. This variability in distribution affected energetic and morphometric descriptors, with high values during high concentrations and lower values when it was dispersed. In the coastal strip of the 55.56 km (30 nautical miles), there was an overlap of juveniles and adults, with normal somatic growth between activities 1 and 4. The main modes in each activity were 8.5, 10, 9.5, and 10.5 cm, respectively. Biomass varied from 6.86 million tons in activity 1 to 3.00 million tons in activity 4, influenced by oceanographic conditions and chlorophyll-a productivity.

ABSTRACT Overfishing, industrial fishing and climate change generate impacts that affect the marine fishery resource, the main source of income and food for coastal populations of artisanal fishers. The creation of conditions that increase the adaptive capacity of fishers will decrease their vulnerability to impacts. This research proposes to determine an Exclusive Zone for Artisanal Fishing-ZEPA as a strategy for sustainable management of fishery resources and climate adaptation for artisanal fishers in the study area. Marxan was used to identify three scenarios for the location of the ZEPA and participatory mapping was carried out with fishers to obtain the fourth scenario. High similarity was found between scenarios 2 and 4, which shows that the scientific (Marxan) and participatory (population) approaches coincide in the location of the ZEPA. The final ZEPA was located in the coastal marine zone of the municipalities of Tumaco and Francisco Pizarro, with a total area of 2,008 km2. Included important conservation targets for artisanal fisheries such as artisanal fishing grounds, ecosystems (mangroves, beaches and estuaries), areas of occurrence of species (seerfish, snappers, sea bass, piangua, marmoset shrimp) among others. More than 80 % of the fishers agreed that the strategy would help reduce their vulnerability to threats such as climatic phenomena, overfishing, pollution, among others. The contribution to climate change adaptation of the study area’s population is highlighted.

RESUMEN La sobrepesca, la pesca industrial y el cambio climático generan impactos que afectan al recurso pesquero marino, la principal fuente de ingreso y alimento de las poblaciones costeras de pescadores artesanales. La creación de condiciones que incrementen la capacidad de adaptación de los pescadores disminuirá su vulnerabilidad a los impactos. Esta investigación propone determinar una Zona Exclusiva de Pesca Artesanal-ZEPA como estrategia de manejo sostenible de los recursos pesqueros y de adaptación climática para los pescadores artesanales del área de estudio. Se utilizó el programa Marxan para identificar tres escenarios para la ubicación de la ZEPA y se realizó una cartografía participativa con pescadores para obtener el cuarto escenario. Se encontró similitud alta entre el escenario 2 y 4, lo que muestra que el enfoque científico (Marxan) y participativo (población) coinciden en la ubicación de ZEPA. La ZEPA definitiva se ubicó en la zona marino costera de los municipios de Tumaco y Francisco Pizarro, con un área total de 2 008 km2. Incluyó objetos de conservación importantes para la pesca artesanal como caladeros de pesca artesanal, ecosistemas (manglares, playas y estuarios), áreas de ocurrencia de especies (sierra, pargos, corvina, piangua, camarón tití), entre otros. Se identificó que más de 80 % de los pescadores estuvo de acuerdo en que la estrategia le aportaría a reducir su vulnerabilidad frente a amenazas como fenómenos climáticos, sobrepesca, contaminación, entre otros. Se resalta la contribución a la adaptación al cambio climático de la población del área de estudio.

A key global change challenge is to significantly reduce the risks of alien taxa causing harmful impacts without compromising the rights of citizens. As part of efforts to address this challenge, South Africa promulgated comprehensive regulations and lists of alien taxa in 2014. In this paper, we review how the lists developed, changed overtime, and how they have been implemented. As of March 2021, 560 taxa were listed under four broad regulatory categories, and between 2014 and 2020, almost 3000 permits were issued to regulate the continued use of listed taxa. The full lists of regulated taxa, permits issued, and corresponding regulations are available in the Supplementary material. A proposed standardised, transparent, and science-informed process to revise the regulatory lists is also presented - as of 30 April 2024, risk analyses have been developed for 140 taxa using the Risk Analysis for Alien Taxa (RAAT) framework and reviewed by an independent scientific body [the Alien Species Risk Analysis Review Panel (ASRARP)] with input from taxon-specific experts. These recommendations are being considered by an interdepartmental governmental decision-making body established in March 2023 [the Risk Analysis Review Committee (RARC)]. Finally, key issues with the listing of alien taxa in South Africa that remain to be resolved are presented. As South Africa's regulatory framework continues to develop, the process of listing and regulating alien taxa will, we believe, become more transparent, consistent, and acceptable to stakeholders, and ultimately facilitate efforts to reduce the harmful impacts of alien taxa. SIGNIFICANCE: The regulation of alien species is a major part of how South Africa addresses biological invasions. For this process to be effective, relevant stakeholders need to be engaged and involved. This paper outlines how species have been regulated in the past, provides regulatory lists in accessible formats, and analyses how the lists have changed over time. A transparent, science-informed process to update the regulatory lists is presented and progress to date reviewed. This process aims to engage interested and affected parties in efforts to preserve the benefits of alien species while reducing the harmful impacts of invasions.

Resumen: Los productos acuáticos reestructurados se procesan principalmente a partir de especies de pescado infravaloradas, recortes de filetes o subproductos de especies de pescado no comerciales. Una de las pesquerías subvaloradas en el sur de México, es la del macabil (Albula vulpes). El objetivo de este estudio fue evaluar el efecto de la adición de harinas no convencionales y la reducción del nivel de cloruro de sodio en las propiedades mecánicas y funcionales de productos reestructurados de macabil. Se elaboraron reestructurados de macabil para analizar las muestras con harina de amaranto (HA) o harina de grillo (HG) doméstico (0 %, 5 % y 10 %) y tres niveles de sal (0 %, 1 % y 2 %). Se evaluó la pérdida de agua por cocción, la cantidad de agua extraíble y la textura de los geles. El uso de ambas harinas no convencionales disminuyó la pérdida de agua por cocción entre un 49.09 % y 61.97 %, con 1 % de sal. La adición de sal redujo el agua extraíble del reestructurado. Los valores de dureza variaron (P < 0.05) entre tratamientos. La mayor dureza se obtuvo en los tratamientos con HA al 10 % y sal al 1 % (64.55 N) y con HG al 10 % y sal al 2 % (63.50 N). La cohesividad varió de 0.53 a 0.71 (adimensional) en los tratamientos con 1 % y 2 % de sal, indicando pocos cambios en la estructura interna por efecto de los aditivos. Las harinas no convencionales permitieron la gelificación proteica, formando reestructurados con propiedades texturales adecuadas para un producto cárnico. La adición del 10 % de HG común o de HA y 1 % de uso de sal, en la formulación de reestructurados de pescado, ofrece una alternativa saludable en el desarrollo de alimentos de pescado.

Abstract: Restructured seafood products are primarily processed from undervalued fish species, fillet trimmings, or byproducts of non-commercial fish species. One of the underrated fisheries in southern Mexico is that of the bonefish (Albula vulpes). The objective of this study was to evaluate the effect of adding non-conventional flours and reducing the sodium chloride level on the mechanical and functional properties of restructured bonefish products. Bonefish restructured products were prepared to analyze samples with (0 %, 5 %, and 10 %) amaranth flour (AF) or cricket flour (CF) and three levels of salt (0 %, 1 % and 2 %). The cooking water loss, the amount of extractable water and the texture from gels were evaluated. The use of both non-conventional flours reduced cooking water loss by 49.09 % to 61.97 % with 1 % salt. The addition of salt reduced the extractable water in the restructured product. Hardness values varied (P < 0.05) among treatments. The highest hardness was obtained in treatments with 10 % AF and 1 % salt (64.55 N) and with 10 % CF and 2 % salt (63.50 N). Cohesiveness ranged from 0.53 to 0.71 (dimensionless) in treatments with 1 % and 2 % salt, indicating minimal changes in internal structure due to additives. Non-conventional flours allowed for protein gelation, forming restructured products with suitable textural properties for a meat product. The addition of 10 % CF or AF and 1 % salt in fish restructured product formulation offers a healthy alternative in the development of fish-based foods.

ABSTRACT. A commercial fishery for the smooth hammerhead shark (Sphyrna zygaena) exists in the waters off northern Peru. Although international and domestic norms regulate this species, adult specimens are becoming rare. Monthly visits to four ports in the La Libertad region were made to measure S. zygaena landings and understand the present state of the fishery. We found that 92% of the specimens landed were juveniles or younger and that 10% of the original biomass remains in the fishery. This highlights that stricter regulations such as protecting breeding areas, establishing a legal catch length, and limiting the catch volume and fishing season are urgently needed to maintain a sustainable fishery.

ABSTRACT The Guatemalan Caribbean has a deepwater fishing area close to the shore around the Cayman Trench. This study reports the first record of the bluntnose sixgill shark (Hexanchus griseus) from this fishing area. Fishery-independent surveys using longlines at ~430-465 m depth, ~11 km northeast of El Quetzalito fishing village, were conducted in 2022 and 2023. Two bluntnose sixgill sharks were captured during these surveys. The sharks were females with total lengths of 300 and 310 cm, with morphological characteristics consistent with this species. These are the first confirmed records of bluntnose sixgill sharks in the western Caribbean Sea. Expanding coastal fisheries to deeper waters presents an emerging threat to deep-sea chondrichthyans in the region. Therefore, periodic fisheries monitoring is needed to estimate their vulnerability to fishing pressure.

Abstract The objective was to determine the incidence of fighting cattle farms in the Spanish dehesa, defining those that are in this territory, and quantifying the hectares they occupy and some productive aspects in order to verify the importance of the breeding of the fighting bull in the maintenance and conservation of its biodiversity. To this end, different documentary sources of livestock associations and the Ministry of Agriculture, Fisheries and Food were consulted; and 304 surveys were carried out among fighting bull farmers in the Spanish provinces with dehesa. The area of the dehesa is 3’515,846 ha distributed in the Autonomous Communities of Andalusia, Extremadura, Castile and Leon, Castilla-La Mancha and Madrid, where there are 726 registered fighting cattle farms, although only 631 of them are active in the Stud Book of the Fighting Bovine Breed (2022), with a downward trend in recent years, and with an average census of 144 dams and 9 bulls, a low stocking rate. The estimated number of farms in the dehesa engaged exclusively in fighting bull farming is 581, with an average area of 534 ha and occupying 315,301 ha, representing 8.97 % of the total Spanish dehesa, although it would amount to 347,744 ha (9.89 %) considering the entire farm with the presence of other complementary activities. These farms are located in 358 municipalities, in which 72.61 % of the census is less than 5,000 inhabitants, which could help to fix the rural population.

Resumen El objetivo fue determinar la incidencia de las ganaderías de lidia en la dehesa española, precisando aquellas que se encuentran en este territorio, y cuantificando las hectáreas que ocupan, y algunos aspectos productivos, a fin de constatar la importancia que supone la crianza del toro de lidia en el mantenimiento y conservación de su biodiversidad. Para ello se consultaron diferentes fuentes documentales de asociaciones ganaderas y el Ministerio de Agricultura Pesca y Alimentación; y se realizaron 304 encuestas a los ganaderos de bovino de lidia de las provincias españolas con dehesa. La superficie de la dehesa es de 3’515,846 ha repartidas en las Comunidades Autónomas de Andalucía, Extremadura, Castilla y León, Castilla-La Mancha y Madrid, donde existen registradas 726 ganaderías de lidia, aunque solo 631 de ellas están activas en el Libro Genealógico de la Raza Bovina de Lidia (2022), siendo su tendencia descendente en los últimos años, y con un censo medio de 144 reproductoras y 9 sementales, una baja carga animal. El número estimado de fincas en la dehesa dedicadas exclusivamente a la ganadería de lidia es 581, presentan una superficie media de 534 ha y ocupan 315,301 ha, suponiendo el 8.97 % del total de la dehesa española, aunque ascendería a 347,744 ha (9.89 %) considerando la totalidad de finca con la presencia de otras actividades complementarias. Estas fincas están localizadas en 358 términos municipales, en los que el 72.61 % del censo es menor de 5,000 habitantes, lo que podría ayudar a la fijación de población rural.

Abstract Introduction: The sea cucumber Holothuria (Halodeima) grisea Selenka, 1867 is a common echinoderm in intertidal regions along the Brazilian coast, which recently became the focus of unreported and unregulated fisheries. This study was carried out in sandy-rocky substrates at Armação do Itapocoroy, Penha, Santa Catarina (26o47’ S; 48o36’ W), near its southern limit of geographic distribution. Objective: To determine the densities (individuals*m-2) of Holothuria (H.) grisea within a spatial-temporal perspective as well as to determine biometric and growth characteristics of the population. Methods: Two-meter wide transects perpendicular to the coastline were carried out in winter and spring 2019 and in summer and spring 2020, in periods of spring low-tides. In each sampling occasion the total number of specimens of H. grisea were determined, and a group of 90 organisms was submitted to in situ biometrics (weight, length and width), and immediately returned alive to their habitat. Results: The densities of H. (H.) grisea were significantly higher in the subtidal sector and lower in the upper intertidal sector with no indication of significant differences among sampling campaigns. Depth was the primary factor explaining the observed density patterns and rugosity of the substrate was secondary but also important. The body length ranged from 5.2 to 22.5 cm, whereas the weight varied from 6.0 to 230 g. The mean and modal lengths were 12.54 and 13 cm, respectively. Approximately 75 % of the population sampled was between 10 and 14 cm and the average weight was 60 g. Estimates from von Bertalanffy growth function indicate that the youngest sea cucumber was one year-old, and the oldest had approximately two and a half years. Conclusions: This is the first study to determine biometric parameters for H. (H.) grisea in southern Brazil and the first one to estimate growth and age estimates for a wild population of this species. The densities recorded in the present study were lower than those previously reported for this region, suggesting anthropic influence.

Resumen Introducción: El pepino de mar Holothuria (Halodeima) grisea Selenka, 1867 es un equinodermo común en las regiones intermareales a lo largo de la costa brasileña, que recientemente se convirtió en foco de pesquerías no declaradas y no reguladas. Este estudio se realizó en sustratos arenosos-rocosos en Armação do Itapocoroy, Penha, Santa Catarina (26o47’ S; 48o36’ W), cerca del límite sur de su distribución geográfica. Objetivo: Determinar las densidades (individuos*m-2) de Holothuria (H.) grisea dentro de una perspectiva espacio-temporal así como determinar las características biométricas y de crecimiento de la población. Métodos: Se realizaron transectos de dos metros de ancho perpendiculares a la línea de costa en invierno y primavera de 2019 y en verano y primavera de 2020, en periodos de bajamar sicigia. En cada ocasión de muestreo se determinó el número total de especímenes de H. (H.) grisea, y se sometió un grupo de 90 organismos a biometría in situ (peso, longitud y ancho), e inmediatamente se los devolvieron vivos a su hábitat. Resultados: Las densidades de H. (H.) grisea fueron significativamente más altas en el sector submareal y más bajas en el sector intermareal superior sin indicios de diferencias significativas entre las campañas de muestreo. La profundidad fue el factor principal que explica los patrones de densidad observados y la rugosidad del sustrato fue secundaria pero también importante. La longitud del cuerpo varió de 5.2 a 22.5 cm, mientras que el peso varió de 6.0 a 230 g. Las longitudes media y modal fueron 12.54 y 13 cm, respectivamente. Aproximadamente el 75 % de la población muestreada midió entre 10 y 14 cm y el peso promedio fue de 60 g. Estimados de la función de crecimiento de von Bertalanffy indican que el ejemplar más joven presentaba un año de edad, mientras el más viejo presentaba cerca de dos años y medio. Conclusiones: Este es el primer estudio que determina parámetros biométricos para una población de H. (H.) grisea en el sur de Brasil y el primero en estimar el crecimiento y edades para una población salvaje de esta especie. Las densidades registradas en el presente estudio fueron inferiores a las reportadas previamente para esta región sugiriendo la ocurrencia de influencia antrópica.