The closure of the anchovy (Engraulis encrasicolus) fishery in the Bay of Biscay between 2005 and 2010 because of low biomass levels provided an opportunity to estimate natural mortality using data ...from egg (daily egg production method, DEPM) and acoustic surveys implemented for the assessment of this population since 1987. Assuming that natural mortality (M) is constant over time and that catchability in both surveys is equal for all ages, M could be estimated using log-linear models on the series of surveys of population numbers at age and seasonal integrated stock assessments. The analysis suggests M values of around 0.9 for a common natural mortality at all ages. However, we found firm evidence that natural mortality at ages 2 and older (M2+) is markedly higher than at age 1 (M1), which indicates senescent mortality, a possibility suggested a long time ago for this type of short-lived species.
To anticipate the response of fish populations to climate change, we developed a framework that integrates requirements in all life stages to assess impacts across the entire life cycle. The ...framework was applied on plaice (Pleuronectes platessa) and Atlantic herring (Clupea harengus) in the North Sea, Atlantic cod (Gadus morhua) in the Norwegian/Barents Seas and European anchovy (Engraulis encrasicolus) in the Bay of Biscay. In each case study, we reviewed habitats required by each life stage, habitat availability, and connectivity between habitats. We then explored how these could be altered by climate change. We documented environmental processes impacting habitat availability and connectivity, providing an integrated view at the population level and in a spatial context of potential climate impacts. A key result was that climate‐driven changes in larval dispersion seem to be the major unknown. Our summary suggested that species with specific habitat requirements for spawning (herring) or nursery grounds (plaice) display bottlenecks in their life cycle. Among the species examined, anchovy could cope best with environmental variability. Plaice was considered to be least resilient to climate‐driven changes due to its strict connectivity between spawning and nursery grounds. For plaice in the North Sea, habitat availability was expected to reduce with climate change. For North Sea herring, Norwegian cod and Biscay anchovy, climate‐driven changes were expected to have contrasting impacts depending on the life stage. Our review highlights the need to integrate physiological and behavioural processes across the life cycle to project the response of specific populations to climate change.
Microplastics (MPs) are thought to be ingested by a wide range of marine organisms before being excreted. However, several studies in marine organisms from different taxa have shown that MPs and ...nanoplastics could be translocated in other organs. In this study, we investigated the presence of MPs in the livers of commercial zooplanktivorous fishes collected in the field. The study focuses mainly on the European anchovy Engraulis encrasicolus but concerns also the European pilchard Sardina pilchardus and the Atlantic herring Clupea harengus. Two complementary methodologies were used to attest the occurrence of MPs in the hepatic tissue and to exclude contamination. 1) MPs were isolated by degradation of the hepatic tissue. 2) Cryosections were made on the livers and observed in polarized light microscopy. Both methods separately revealed that MPs, mainly polyethylene (PE), were translocated into the livers of the three clupeid species. In anchovy, 80 per cent of livers contained relatively large MPs that ranged from 124 μm to 438 μm, showing a high level of contamination. Two translocation pathways are hypothesized: (i) large particles found in the liver resulted from the agglomeration of smaller pieces, and/or (ii) they simply pass through the intestinal barrier. Further studies are however required to understand the exact process.
Display omitted
•Microplastics were found for the first time in liver of wild Clupeiforme fishes.•Eighty per cent of anchovies had one or more microplastic(s) in their liver.•Microplastics measured 323 μm on average.
Microplastics are translocated in the liver of wild fishes meaning that microplastic pollution has a more important impact than previously supposed.
Every day large amounts of fish waste are produced and grossly discarded in markets around the world causing environmental and hygiene issue. The use of these scraps for the production of materials ...with higher added value can definitely contributed to solve this problem. In this work, 10% and 20% of anchovy fishbone powder (EE), obtained by market waste, were microbiological and mechanical tested and subsequently added to polylactic acid (PLA) and to a commercial blend of biodegradable co-polyesters (Mater-Bi®). Rheological characterization suggests the potential printability of all prepared composites filaments. 10% EE filled composites showed outstanding printability. Morphological analysis confirmed the obtainment of good dispersion of the filler and the excellent adhesion of EE particles with the matrices in the composites filament and in 10% printed samples. The filler effectively acted as reinforcement in flexural and impact test: for MB and PLA, the addition of EE leads to an increase of flexural modulus of about 23% and 32% respectively. In tensile test both composites turn out to be influenced by the oil contained in the filler that act as plasticizer: the elongation at break of MB increased by 364% when 10% of EE was added. The experimental data obtained by tensile tests showed an opposites behavior than those predicted by Halpin–Tsai model, presumably due to the presence of residual fish oil acting as internal slipping agent.
Display omitted
•Anchovy fishbone powder was produced and added to biopolymeric matrices.•An innovative green composite suitable for 3D printing applications was produced.•Anchovy fishbone powder displayed good adhesion with two different biopolymeric matrices.•Biocomposites with 10% of fishy filler showed outstanding printability for FDM.•The filler acts as reinforcement in flexural and impact performances of composites.
A comparative analysis of body shape was performed on 841 specimens of anchovy collected from 21 catches from the Sea of Azov, the Kerch Strait, and the Black Sea off Crimea and the northeastern ...coast of the Caucasus in 2006–2007 and 2016–2017. Twenty-three measurements between 12 homologous landmarks of the body of each specimen according to the Truss Network System served as characters for analysis. Fifteen characters showed significant differences between the Azov anchovy
Engraulis encrasicolus maeoticus
Pusanov, 1926 and the Black Sea anchovy
E. encrasicolus ponticus
Alexandrov, 1927. Specimens of the Azov subspecies had larger relative values for all characters of the head region, the height of the trunk region, the relative length of the bases of the dorsal and anal fins, and the height of the base of the caudal fin. Specimens of the Black Sea subspecies had a greater postdorsal length and a larger distance from the end of the dorsal fin base to the end of the anal fin base. A multivariate principal component analysis revealed the highest variability of characters of the body height, which depends on the body condition of the fish and demonstrates seasonal dynamics. The second group combines characters that do not have a seasonal component (dimensions of the head region, lengths of the bases of the dorsal and anal fins, and postdorsal distance) and can be used for distinguishing the shape of the Azov and Black Sea anchovies. The success rate of classification of Azov and Black Sea anchovies according to the body shape measurement characters using discriminant analysis was 83.4%.
Fish waste utilization to obtain protein hydrolysates has been demonstrated to be a useful strategy to face both environmental and economic impacts while obtaining high-value products with remarkable ...biological and nutritional properties. In the present study, protein hydrolysates obtained from anchovy
(APH) by-products were assessed for their potential biological activities in both in vitro and in vivo models. The treatment with APH exerted a significant protection against LPS-induced inflammation in RAW 264.7 cells, decreasing the protein expression of pro-inflammatory mediators (i.e., COX-2) and inhibiting the nuclear translocation of NF-κB through IκB-α. Moreover, APH modulated the expression of iNOS, MnSOD and HO-1, thus decreasing the severity of oxidative stress. The supplementation of APH in the diet of ApoE knockout mice down-regulated the proinflammatory cytokines (i.e.,
, IL-1α, IL-1β, IL-6) in both aorta and heart tissues, and modulated the expression of oxidative stress-related genes (Cu/ZnSod, MnSod, Cat, Gpx and Ho), indicating that APH can exert a beneficial role, having anti-inflammatory and antioxidant activities. The nutritional properties of APH, together with their biological activities herein reported, highlight the possibility of obtaining bioactive molecules from fish waste and encourage their use as potential nutraceuticals in food and pharmaceutical industries in the next future.
The population of the Endangered African penguin Spheniscus demersus has decreased by > 65% in the last 20 years. A major driver of this decrease has been the reduced availability of their principal ...prey, sardine Sardinops sagax and anchovy Engraulis encrasicolus. To date, conservation efforts to improve prey availability have focused on spatial management strategies to reduce resource competition with purse-seine fisheries during the breeding season. However, penguins also undergo an annual catastrophic moult when they are unable to feed for several weeks. Before moulting they must accumulate sufficient energy stores to survive this critical life-history stage. Using GPS tracking data collected between 2012 and 2019, we identify important foraging areas for pre- and post-moult African penguins at three of their major colonies in South Africa: Dassen Island and Stony Point (Western Cape) and Bird Island (Eastern Cape). The foraging ranges of pre- and post-moult adult African penguins (c. 600 km from colony) was far greater than that previously observed for breeding penguins (c. 50 km from colony) and varied considerably between sites, years and pre- and post-moult stages. Despite their more extensive range during the non-breeding season, waters within 20 and 50 km of their breeding colonies were used intensively and represent important foraging areas to pre- and post-moult penguins. Furthermore, penguins in the Western Cape travelled significantly further than those in the Eastern Cape which is likely a reflection of the poor prey availability along the west coast of South Africa. Our findings identify important marine areas for pre- and post-moult African penguins and support for the expansion of fisheries-related spatio-temporal management strategies to help conserve African penguins outside the breeding season.
The ingestion of microplastics and natural fibres (<5 mm) was assessed for two commercial fish species in the western Mediterranean Sea: Sardina pilchardus and Engraulis encrasicolus. ...Gastrointestinal tracts from 210 individuals from 14 stations were examined with 14.28–15.24% of the small pelagic fish S. pilchardus and E. encrasicolus having ingested microplastics and natural fibres. A latitudinal increase in condition index (Fulton's K) of S. pilchardus gave an indication that larger individuals with better physical condition are less likely to ingest microplastics and natural fibres. Fibres were the most frequent particle type (83%) and Fourier Transform Infrared spectroscopy (FT-IR) analysis indicated polyethylene terephthalate was the most common microplastics material (30%). Results from this study show that both microplastics and natural fibres of anthropogenic origin are common throughout the pelagic environment along the Spanish Mediterranean coast.
•Fifteen percent of sampled European pilchards and European anchovies ingested microplastics and natural fibres.•Condition index (Fulton's K) influences the ingestion of microplastics and natural fibres in the sampled European pilchard.•The ingestion of microplastics and natural fibres in these fish species is widespread along the Spanish Mediterranean coast.•Eighty-three percent of ingested anthropogenic particles were fibres.
The European anchovy, Engraulis encrasicolus, is currently one of the principal target species for commercial fisheries in Europe. In this study, the mitochondrial Control Region (CR) and the ...Cytochrome Oxidase I (COI) mitochondrial gene were analyzed in 74 specimens of E. encrasicolus from four localities in the central Mediterranean. In both populations, the two markers revealed the presence of two main haplogroups, A and B, already detected in previous investigations of different classes of molecular markers. Both CR and COI markers consistently identified two haplogroups. The COI sequence analysis identified a non-synonymous transversion (T to G) at position 116 of the translated sequence, resulting in an amino acid change. All COI sequences of haplogroup A had an amino acid sequence with alanine in this position, while serine was present in the same position in haplogroup B. The two haplogroups A and B were also discriminated by the variable number of TACA elements at the 5'-end of the mitochondrial CR. The selection tests applied to the COI dataset revealed that codon 116 was not under positive selection, that seven amino acid changes were under purifying selection, and that two amino acids were under episodic positive selection.
Anchovy population expansion in the North Sea Petitgas, Pierre; Alheit, Jürgen; Peck, Myron A. ...
Marine ecology. Progress series (Halstenbek),
01/2012, Volume:
444
Journal Article
Peer reviewed
Open access
The abundance and spatial occupation of European anchovyEngraulis encrasicolushave increased in the North Sea since the mid-1990s. We use a cross-disciplinary approach combining genetics, transport ...modelling, survey time series analyses and physical oceanographic modelling to investigate 3 hypotheses on the reasons for this change. Evidence from connectivity studies suggests that the population of North Sea anchovy is separate from that in the Bay of Biscay. The recruitment pulses observed in survey data fit a life cycle which includes spawning in early summer and larval development in late summer. This also supports the concept of population expansion originating from local remnant population(s). In terms of growth physiology, suitable thermal windows have expanded, making conditions more favourable for life cycle closure and population persistence/productivity. In addition to the increased frequency of warm summers, which favour larvae and juvenile growth, the decrease in the number of severe winters is also likely to improve overwinter survival. Overall, the evidence supports the hypothesis that the increase in anchovy abundance originated from the improved productivity of existing populations. This increase was associated with an expansion in thermal habitats and is probably not due to a northward shift in the distribution of southern conspecifics.
PDF
