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Fish live in a complex world and must actively adapt their swimming behavior to a range of environments. Most studies of swimming kinematics focus on two-dimensional properties related to the bending wave that passes from head to tail. However, fish also twist their bodies three dimensionally around their longitudinal axis as the bending wave passes down the body. We measured and characterized this movement, which we call 'wobble', in six species of elongate fishes (Anoplarchus insignis, Xiphister mucosus, Lumpenus sagitta, Pholis laeta, Apodichthys flavidus and Ronquilus jordani) from three different habitats (intertidal, nearshore and subtidal) using custom video analysis software. Wobble and bending are synchronized, with a phase shift between the wobble wave and bending wave. We found that species from the same habitats swim in similar ways, even if they are more closely related to species from different habitats. In nearshore species, the tail wobbles the most but, in subtidal and intertidal species, the head wobbles more than or the same as the tail. We also wanted to understand the relationship between wobble and the passive mechanics of the fish bodies. Therefore, we measured torsional stiffness and modulus along the body and found that modulus increases from head to tail in all six species. As wobble does not correlate with the passive properties of the body, it may play a different role in swimming behavior of fishes from different habitats. [ABSTRACT FROM AUTHOR]

Age, growth, sex and gonadal maturation of the shanny, Liphorys pholis, were determined in specimens caught in a rocky intertidal area in northern Portugal in order to provide essential ecological data on the species. This study represents the first available reference in the literature for L. pholis in a southern European location. Totals of 251 individuals (115 females, 99 males, 37 undetermined; total length: 30-172 mm) were collected seasonally (November 2013, March, June, and September 2014) in a northern Portuguese rocky beach (Póvoa do Varzim: 41°23′47.79″N; 08°46′45.48″W) using fine-mesh aquarium fishnets during low tides. Marginal increment analysis showed that one translucent and one opaque zone was formed each year in the sagittal otoliths. Ages of L. pholis ranged from 0 to 6 years. Males were larger and older than females. The von Bertalanffy growth equation parameters considering all individuals were L∞ = 184 mm, K = 0.26 mm/year, t0 = −1.34. The annual variation of the fish condition and hepatosomatic indexes appeared to be related to the mobilization of the somatic reserves prior to reproduction. Maximum gonadosomatic index for males and females coincided with the breeding seasons (November and March). The sex ratio was close to 1:1, all maturity stages included. Furthermore, some stages of sexual development in males and females were observed during the same season, and several germinal cells were also observed at the same time within a single ovary or testis, indicating that L. pholis is an asynchronous and multiple spawner. Maturation for both sexes appears to be around 70 mm TL and prior to reaching 1 year of age. [ABSTRACT FROM AUTHOR]

Information on the genital morphology of male and female Lipophrys pholis is provided, as well as for two other sympatric blenniid species, Coryphoblennius galerita and Lipophrys trigloides. The use of non-invasive sex determination procedures described may be extremely useful not only for ecological studies but also as a proxy for the detection of environmental exposure to endocrine disruptive chemicals, given that blennies have been proposed as potential sentinel species for chemical contamination. [ABSTRACT FROM AUTHOR]

Abstract: Oil spills are an importance source of polycyclic aromatic hydrocarbons (PAHs) in the aquatic environment. Intertidal communities are particularly sensitive since most organisms from these ecosystems are sessile or present reduced mobility. Hence, it is important to validate the use of resident species as sentinels to characterize the impact of oil spills on the rocky shores and the improvement during the restoration process. Recently the advantages of using the shanny Lipophrys pholis in pollution monitoring within the northwestern Atlantic coast has been pointed out. Therefore, with the aim of further validating the use of L. pholis in pollution monitoring associated with petrogenic hydrocarbon contamination, a multi-biomarker approach study was carried out 1 week after a moderate oil spill from the waste treatment plant (WTP) of the major Portuguese refinery in the north of Portugal (Petrogal). Fish collected at 2km from the accident displayed a significant induction of ethoxyresorufin-O-deethylase activity (EROD) and fluorescent aromatic compounds (FACs) in bile (up to a 5-fold induction) in comparison with the pre-spill scenario, and a 15% induction in erythrocytic nuclear abnormalities (ENA), a biomarker of genotoxicity. In contrast, no significant differences were recorded in the reference site. In order to better characterize the time-course accumulation of FACs in bile after a PAH insult, laboratory exposure of L. pholis to benzo[a]pyrene (B[a]P) was performed. A clear dose–response accumulation of B[a]P metabolites was observed that closely reflected nominal exposure concentrations already after 3d. Overall, the findings of the present study highlight the potential of L. pholis in pollution monitoring dealing not only with chronic contamination, but also with oil spill accidents of a moderate scale. Taking into consideration that EROD and FACs determinations in L. pholis are cost effective, rapid and easy to use, they offer a great potential to be incorporated into risk assessment of PAHs in the scope of national monitoring programs and the European Water Policy legislation. [Copyright &y& Elsevier]

This study is part of a project aiming to validate the use of the intertidal shanny Lipophorys pholis as a sentinel species in pollution monitoring in NW European marine ecosystems. To this end, a characterisation of acethylcholin (AChE), butyrylcholin (BChE) and propionylcholin (PrChE) esterases in L. pholis muscle was performed and the results indicated that AChE was predominant. Furthermore, the use of eserine sulphate and BW284c51 (0.64–800μM), and iso-OMPA (0.08–16mM), confirmed the measurement of true cholinesterases (ChEs) as well as the presence of pseudocholinesterases. The field application of these markers to L. pholis, sampled in seven locations along the Portuguese coast, revealed that fish were likely to be affected by neurotoxic compounds. This was indicated by the significant depletion of AChE (p <0.05) in animals collected at urban and industrialised sites, compared with those from reference locations. The inclusion of a marker of effect, measured as lipid peroxidation levels in muscle tissue, also revealed the existence of site differences. Overall, the study further validates the utility of L. pholis in pollution monitoring studies. [Copyright &y& Elsevier]

The homing ability of an intertidal fish, the shanny Lipophrys pholis, was investigated using two experiments that were based on the shanny’s natural propensity to home to a refuge. A displacement experiment demonstrated that the fish were able to accurately locate the previous position of a refuge once the shelter itself had been removed so that it could not be used as a cue to directly signal the goal location. This shows that the shanny can encode information about its familiar surroundings into a spatial map and use this information to home. A second experiment in which the cues internal and external to the experimental tank were put in conflict with one another suggested that the shanny can encode cues that are both intra- and external-tank cues in its representation of space, but that there is individual variation in the type of cues that are used, or memorized. [ABSTRACT FROM AUTHOR]

Evaluating the impacts of point source discharges on fish species in estuarine environments can be challenging because of a paucity of resident species. We evaluated the biology of rock gunnel ( Pholis gunnellus) at three relatively uncontaminated sites in the Bay of Fundy, along the Atlantic coast of Canada. Rock gunnel are seasonally resident (April to November) in tide pools, but little was known about their life history in Atlantic Canada or their potential for use for monitoring environmental quality. Fish were collected between April and November, and ranged from 2.46 g--15.2~g in weight and 97 mm-170 mm in length, with a maximum age of 7 years. Both males and females were similar in size, and both reached sexual maturity at a size of 5.5 g. Organ weights and condition indices of fish were stable from spring when they returned from offshore (April to May) until late summer (August to September), but fall fish (October to November) had slightly larger gonads, livers and condition indices. Rock gunnel may be a useful indicator to provide insight into local impacts of point sources over a short time period. However, they do not provide adequate information on reproductive development and performance since they are not exposed to onshore contaminants during the periods of gonadal development that have most commonly found to be sensitive to anthropogenic stressors. [ABSTRACT FROM AUTHOR]

The intertidal biota of the North Atlantic is characterized by two disjunct communities (North American and European) exposed to different climatic regimes during the Pleistocene and in the Holocene. We collect multilocus DNA sequence data from the nearshore fish Pholis gunnellus to help uncover processes determining biogeographical persistence during periodic coastal glaciations. Coalescent-based estimates from the multilocus DNA sequence data suggest that P. gunnellus persisted on both sides of the North Atlantic throughout the last two glacial maxima (> 202 000 years) with little trans-Atlantic gene flow since divergence, very little structure among populations within Europe (ΦST<0.05) and some structure within the North American coastline (ΦST = 0.0–0.21). Although the ecological flexibility and high local migration of P. gunnellus could have enhanced this species’ survival across the Atlantic, logistic regression did not find a significant determinant of trans-Atlantic persistence when considering 12 other North Atlantic phylogeographical studies from the literature. [ABSTRACT FROM AUTHOR]

The behaviour of Serpula vermicularis reef worms and associated mobile fauna in Loch Creran, on the west coast of Scotland, was recorded for six weeks using underwater television. The reef worms were extended almost continually, generally only retracting when stimulated by the close proximity of a predator. The length of hiding time varied according to the species triggering the reaction. The mean length of time retracted was 21s. Fauna associated with the reefs included the corkwing wrasse Crenilabrus melops, ballan wrasse Labrus bergylta, black squat lobster Galathea squamifera and velvet swimming crabs Necora puber. There were few significant associations between tidal cycle and the presence/activity of associated fauna but a number of fish and crustacean species appeared to be influenced by the diurnal cycle. Gobies were recorded during daylight only with peak observations around midday while wrasse, butterfish Pholis gunnellus and cod Gadus morhua were crepuscular. The dawn and dusk appearance of juvenile cod in large shoals is suggestive of a nightly migration. [Copyright &y& Elsevier]

Discusses a light- and electron-microscopic study on infection of the digestive tract of the fish Lipophrys pholis by Loma dimorpha. Relationship between infection and host size and sex; Information on the study specimens; Findings of the study.

Abstract: The temporal patterns of feeding activity of Lipophrys pholis and Coryphoblennius galerita were studied by snorkelling dives during high-waters. The feeding activity was especially intense during the rising-tide when compared to the ebbing-tide. The relative abundances of C. galerita and small L. pholis observed on rock-walls were higher during the rising- and high-tide. However, L. pholis larger than 7–8cm showed higher relative abundance on rock-walls during the ebbing phase, apparently because they move up and down with the tide, and many individuals were in their downward movements as the tide ebbs. It is hypothesized that the asymmetry in feeding pattern observed in both species reflects a trade off between two conflicting needs, maximizing feeding time and reaching their low-tide shelters in time, avoiding the risk of getting stranded in unsuitable locations. [Copyright &y& Elsevier]

Length-weight relationships ( LWRs) were determined for three zoarcoid fish species: Zoarces elongatus Kner, 1868, Pholis fangi (Wang & Wang, 1935) and Chirolophis japonicus Herzenstein, 1890. Samples were collected from the coastal waters of the northern Yellow Sea (near Dalian City) using bottom trawl nets (20 mm stretched mesh size in the cod-end) for Zoarces elongatus and Pholis fangi and set gill nets (mesh size 15.6 mm) for Chirolophis japonicus. Samples were taken from mid-March to early April 2017. Parameter b values in the fitted LWRs were 3.119, 3.440 and 3.423 for Z. elongatus, P. fangi and C. japonicus, respectively. [ABSTRACT FROM AUTHOR]

In this study, the complete mitochondrial genome (mitogenome) sequence ofPholis nebulosushas been determined by long polymerase chain reaction and primer-walking methods. The mitogenome is a circular molecule of 16 524 bp in length, including the typical structure of 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 2 non-coding regions (L-strand replication origin and control region), the gene contents of which are identical to those observed in most bony fishes. Within the control region, we identified the termination-associated sequence domain (TAS), and the conserved sequence block domain (CSB-F, CSB-E, CSB-D, CSB-C, CSB-B, CSB-A, CSB-1, CSB-2, CSB-3). [ABSTRACT FROM AUTHOR]

Patellid limpets are key species on rocky shores, structuring intertidal assemblages through their grazing. Their role as prey for fish is, however, often overlooked in studies of intertidal ecosystem functioning. The shanny Lipophrys pholis is a common predator of limpets on rocky shores in Northern Europe and, in this study, we examined the characteristics of its predation on limpets based on prey size. The limpet size range that adult L. pholis (10-12.5 cm) can eat was examined in the laboratory using Patella depressa in 0.2 cm classes, varying between 0.5 cm and 3.0 cm in maximum shell length. There was a limpet size refuge above 1.8 cm, while all smaller sizes were readily consumed by the shanny. The predator attacking behaviour was also examined and found to vary with prey size. Limpets up to 0.8 cm were crushed by the jaw-constricting force and eaten whole, whereas larger prey were prised from the substratum and the body subsequently separated from the shell. To examine whether there was a L. pholis preference for P. depressa size, a two-stage laboratory experiment was done using two size classes defined as small (0.7-0.8 cm maximum shell length) and large (1.5-1.6 cm maximum shell length). In the first stage, the predator was given each limpet size class separately. In the second stage, the fish was given a choice between the two classes. Lipophrys pholis was shown to have a preference for the large size class (1.5-1.6 cm). The average number of limpets consumed by the shanny was examined for the duration of one high-tide typical of the central region of Portugal (≈ 4 h). On average, approximately five limpets (up to an eight limpet maximum) were consumed. The present study shows that L. pholis has a feeding preference based on limpet size, which suggests that the limpet population structure and intra- and inter-specific interactions may be influenced by the shanny predation. [ABSTRACT FROM AUTHOR]