8 research outputs found
Advantages and insights from a hierarchical Bayesian growth and dynamics model based on salmonid electrofishing removal data
Growth is a fundamental ecological process of stream-dwelling salmonids which is strongly interrelated to critical life history events (emergence, mortality, sexual maturity, smolting, spawning). The ability to accurately model growth becomes critical when making population predictions over large temporal (multi-decadal) and spatial (meso) scales, e.g., investigating the effect of global change. Body length collection by removal sampling is a widely-used practice for monitoring fish populations over such large scales. Such data can be efficiently integrated into a Hierarchical Bayesian Model (HBM) and lead to interesting findings on fish dynamics. We illustrate this approach by presenting an integrated HBM of brown trout (Salmo trutta) growth, population dynamics, and removal sampling data collection processes using large temporal and spatial scales data (20 years; 48 sites placed along a 100 km latitudinal gradient). Growth and population dynamics are modelled by ordinary differential equations with parameters bound together in a hierarchical structure. The observation process is modelled with a combination of a Poisson error, a binomial error, and a mixture of Gaussian distributions. Absolute fit is measured using posterior predictive checks, which results indicate that our model fits the data well. Results indicate that growth rate is positively correlated to catchment area. This result corroborates those of other studies (laboratory, exploratory) that identified factors besides water temperature that are related to daily ration and have a significant effect on stream-dwelling salmonid growth at a large scale. Our study also illustrates the value of integrated HBM and electrofishing removal sampling data to study in situ fish populations over large scales
Upstream migration of anadromous and potamodromous brown trout: patterns and triggers in a 25-year overview
Producción CientíficaRiver fragmentation and alterations in
flow and thermal regimes are the main stressors
affecting migrating fish, which could be aggravated by
climate change and increasing water demand. To
assess these impacts and define mitigation measures, it
is vital to understand fish movement patterns and the
environmental variables affecting them. This study
presents a long-term (1995–2019) analysis of
upstream migration patterns of anadromous and
potamodromous brown trout in the lower River
Bidasoa (Spain). For this, captures in a monitoring
station were analyzed using Survival Analysis and
Random Forest techniques. Results showed that most
upstream movements of potamodromous trout
occurred in October–December, whereas in June–July
for anadromous trout, although with differences
regarding sex and size. Both, fish numbers and dates
varied over time and were related to the environmental
conditions, with different influence on each ecotype.
The information provided from comparative studies
can be used as a basis to develop adaptive management
strategies to ensure freshwater species conservation.
Moreover, studies in the southern distribution range
can be crucial under climate warming scenarios, where
species are expected to shift coldwards.Proyecto de innovación docente de la Universidad de Valladolid (PIF-UVa 2017)Ministerio de Ciencia, Innovación y Universidades (grant PTQ2018-010162)Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL
International Standardization of Common Names for Iberian Endemic Freshwater Fishes
Las especies de peces dulceacuícolas endémicas de la península Ibérica carecen de nombres comunes en inglés, lo cual frecuentemente causa inconvenientes a los autores en el momento de publicar para una audiencia internacional. Con el objetivo de llenar este vacío, se presenta una lista actualizada de las especies de peces dulceacuícolas endémicas de la península Ibérica con una propuesta razonada de designación internacional estandarizada junto con los nombres comunes en español y/o portugués adoptados en los Libros Rojos NacionalesIberian endemic freshwater fishes do not have standardized common names in English, which is usually a cause of inconveniences for authors when publishing for an international audience. With the aim to tackle this problem, an updated list of Iberian endemic freshwater fish species is presented with a reasoned proposition of a standard international designation along with Spanish and/or Portuguese common names adopted in the National Red Data BooksOs peixes dulciaquícolas endémicos da Península Ibérica näo possuem um nome comum devidamente padronizado em Inglês, o que causa problemas aos investigadores quando publicam em revistas com uma audiência internacional. O presente trabalho procurou resolver esta questäo, incluindo uma lista actualizada das espécies piscícolas endémicas da Península Ibérica e uma proposta fundamentada de nomes comuns em Inglês, juntamente com as designaçöes comuns em Espanhol e/ou Português adoptadas nos respectivos Livros Vermelhos Nacionai
Piscardo – Phoxinus bigerri Kottelat, 2007
Peces - Orden Cypriniformes - Familia Cyprinidae en la Enciclopedia Virtual de Vertebrados Españoles, http://www.vertebradosibericos.org/. Versiones anteriores: 26-05-2010A comprehensive review of the natural history
of the Pyrenean minnow Phoxinus bigerri in Spain.Peer reviewe
Pez gato negro – Ameiurus melas (Rafinesque, 1820)
Peces - Orden Siluriformes - Familia Ictaluridae en la Enciclopedia Virtual de Vertebrados Españoles, http://www.vertebradosibericos.org/A comprehensive review of the natural history of the black bullhead Ameirus melas in Spain.Peer reviewe
Data from: Bone-to-body biometric relationships for Owens and Lahontan tui chubs and their hybrids in California
Regression parameters for the length of several bony structures against fish body length, and for body length against body weight, were determined for Owens tui chub (Siphateles bicolor snyderi), Lahontan tui chub (S. b. obesa) and hybrid swarm deriving from the two species. A total of 211 individuals from 16 localities from the Owens River and neighboring basins along the border between California and Nevada were used for regression analyses. The coefficient of determination of linear regressions for scales, pharyngeal arches, dentaries, cleithra, and opercula against body length were consistently high (r2 埲.9). Differences between subspecies were mainly with reference to the intercept parameter in comparisons involving Lahontan tui chub. Coefficients of determination from log-linear length-weight regressions were also high (r2 埲.9) for individual taxa and for the pooled data set combining both Lahontan and hybrid species. The length-weight relation ship did not differ between subspecies. Estimates of the length-weight relationship using data pooling both Lahontan and hybrid tui chub suggest a weak allometric growth effect (P<0.05). The bone-length to body-length and body-length to body-weight relationships presented here will be useful tools for future dietary studies of tui chub predators as well as for archaeological and paleontological studies on tui chub remains
Current status and future perspectives of Italian finfish aquaculture
Currently available data show that shellfish and finfish production in Italy, derived both from fisheries and aquaculture activities, is on the order of 474,000 tons, each activity representing 50% of the total amount. In this context, the finfish aquaculture industry contributes on average 31 % to the national aquaculture production and on average 59 % of its value, giving a total amount of 72,000 tons and a value of around 351 million \u20ac (2010).
According to FEAP statistics, Italy is the fourth largest finfish producer in EU27, after the UK, Greece, and Spain, while it is also one of the six largest finfish producers among the non-EU and EU member countries, together with Norway, UK, Greece, Turkey, and Spain. Presently, fish culture activities are mainly focused on rainbow trout (Oncorhynchus mykiss, 55.5 %), followed by European sea bass (Dicentrarchus labrax, 13.6 %), gilthead sea bream (Sparus aurata, 12.2 %), gray mullet (Mugil cephalus, 5.3 %), sturgeon (Acipenser spp., 2 %), and European eel (Anguilla anguilla, 1.7 %).
Over the last 20 years, freshwater fish production and aquaculture (trout, carp, and eel) have decreased in Italy, with the exception of sturgeon. In contrast, marine fish production has significantly increased during the same period, and the two leading species, European sea bass and gilthead sea bream, presently contribute 25.8 % of the finfish production. From 1,900 tons in 1990, production reached 19,000 tons in 2010, with a 900 % increase, at an average percentage of 4.5 %. In addition, new marine fish species were successfully cultured over the same period.
This review outlines the past and present situation of finfish culture in Italy and discusses future developments and priorities, with particular emphasis on new, emerging aquaculture species