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opencc-by-4.0Dec 2003View details →

Fig. 5. Rhinogobius nammaensis, ZRC 46582, 43.0 in Three New Freshwater Gobies Of The Genus Rhinogobius (Teleostei: Gobiidae) From Northeastern Laos

Fig. 5. Rhinogobius nammaensis, ZRC 46582, 43.0 mm SL; head lateral-line system. Scale bar = 1 mm.

opencc-by-4.0Nov 2023View details →

Data from: Trophic position and niche overlap of an Asian weatherfish (Misgurnus bipartitus), western tubenose goby (Proterorhinus semilunaris), and native benthic fish species

The dataset belonging to the paper "Trophic position and niche overlap of an Asian weatherfish (Misgurnus bipartitus), western tubenose goby (Proterorhinus semilunaris), and native benthic fish species" published in Aquatic Invasions (paper in press; doi link will be added later), is provided here. The dataset consists of δ13C and δ15N (‰) stable isotope ratios of taxa of fish, macroinvertebrates, plants, alga, and soil. If applicable, the length of the taxon was included. Below, methodological information is provided on the study site, the sampling process, the sampling preparation, and the stable isotope analysis. For references, see the published paper in Aquatic Invasions. Study siteThe study site concerned a section of the lowland brook Tungelroysebeek (51°14.38'N, 005°52.086'E – 51°14.26'N, 005°47.77'E) near the village Tungelroy in the Province of Limburg, the Netherlands. This brook of 35 km length has several tributaries before discharging into the River Meuse. Over most of its course, the brook was meandering and had a well-developed riparian and hydrophyte vegetation. During sampling the mean water temperature was 16.0 °C, conductivity 664 µS/cm, pH 7.3, water velocity 0.2 m/s, depth 70 cm, and Secchi depth 60 cm. The brook width ranged between 5-8 m and its bed substrate predominantly consisted of sand. SamplingSamples of fish, macroinvertebrates, macrophytes, dead organic material, and bottom soil substrate were collected in October 2019. The samples were collected in the stretch of the brook that is denoted in Fig. 1 of the paper. Fish were caught using handheld electrofishing equipment (Bretschneider EFGI 650). After catching, the fish were euthanized using a neutralized benzocaine solution of 100 mg l-1. Macroinvertebrates were collected using 70x55 cm dip nets with a mesh size of 1 mm. Helophytes, floating-leaved, and submerged aquatic macrophytes were collected by hand. Soil samples were collected by means of a hollow soil sampling tube with a diameter of 5 cm. A Nikon SMZ800 stereo microscope with a 10-63 magnification was used for the identification of small macroinvertebrates. Sample preparation All samples were transported to the laboratory and stored separately at -18° C until preparation. To obtain muscle samples a piece of 0.5-1 cm of the dorsal tissue of each fish was dissected. Muscle tissue samples were dissected from fish, crayfish, and unionid mussels. Other macroinvertebrates were stored alive for two days at 5 °C to empty their intestinal contents. Subsequently, these invertebrates were rinsed with tap water and then with demineralized water before processing. From unionid mussels, muscle tissue of a similar size was dissected. Of small mollusks, all soft body tissues were used. For small mollusks and other macroinvertebrates, individuals of the same species were pooled to obtain enough material (0.22-0.26 mg) for analyses. For crayfish, muscle tissue of the abdomen was used while the intestine was removed. The stems, leaves, and roots of individual plants were pooled. After preparation, all samples were stored at -80 °C until freeze drying. Freeze drying was carried out at -90 °C for 24-48 hours for fish and macroinvertebrate samples. Plant, dead organic material, and soil samples were freeze dried at least 48 hours. After freeze drying, the samples were grounded with aluminum balls, for 2 min at 30 rpm, using a Retsch MM 400. Subsequently, the grounded samples were weighted in tin cups (Elemental Microanalysis 8 x 5 mm) and prepared for isotope analyses. For the fish and invertebrate samples, 0.22-0.26 mg was weighted. For plants and soil, separate samples were weighted for carbon (10 mg) and nitrogen (40 mg) analyzes.  Stable isotope analysesCarbon and nitrogen stable isotopes were measured using a Thermo Scientific FLASH 2000 HT Elemental Analyzer with a Thermo Scientific DELTA V Advantage Next Generation Isotope Ratio mass spectrometer. Reference gasses were calibrated with the IAEA standards (IAEA-N-2 and IAEA-CH-6), with a maximum deviation of 0.15‰. As an internal standard control, caffeine was used and the 13C/12C and 15N/14N of every sample were determined (in ‰). The isotope ratios (R) δ13C and δ15N are relative to Vienna PDB and atmospheric N2 and were calculated by: δ13C or δ15N = (Rsample/Rstandard − 1) * 1000 Abstract Co-occurring and morphologically similar species have adapted to differential niches for minimizing competition. An invasive alien species can occupy an 'empty niche' in introduced ranges. Alternatively, the invader may occupy an overlapping niche and compete with native species to a certain degree. In a Western European lowland brook with high nutrient loads, we studied a benthic community of five fish species, including two alien species: an Asian weatherfish (Misgurnus bipartitus) and the western tubenose goby (Proterorhinus semilunaris). The native species concerned stone loach (Barbatula barbatula), spined loach (Cobitis taenia), and gudgeon (Gobio gobio). Because of the unknown effects of the invaders on native benthic fish species, the trophic position, isotopic niche overlap, and potential food competition among these species were identified using nitrogen and carbon stable isotopes. The trophic levels of the five fish species indicated that they are secondary consumers. Body size of native fish species correlated significantly negative with their δ15N (‰) signature, in contrast with the invaders indicating that the latter are generalists. Significant isotopic niche overlap was observed among all benthic species. The degree of niche overlap of M. bipartitus was the highest (91.8%) with the G. gobio. Proterorhinus semilunaris had the highest degree of niche overlap (91.2%) with the (B. barbatula. It was notable that the observed niche overlap between the native B. barbatula and C. taenia was high (99.2%). Overlap between M. bipartitus and P. semilunaris was low (8.9% overlap), indicating little resource competition between these alien species. Native species showed wider isotopic niches than the invaders. Bayesian mixing models revealed that native and alien species slightly differ in their main diet. The results suggest that the invaders are plastic in their resource use, leading to niche differentiation and promoting co-existence of benthic fish species.

opencc-zeroJan 2022View details →

Supplementary data to "Alternative reproductive tactics are associated with sperm performance in invasive round goby from two different salinity environments"

During male-male competition, evolution can favor alternative reproductive tactics. This often results in a dominant morph that holds a resource, such as a nest for egg laying, competes with a smaller sneaker morph that reproduces by stealing fertilizations. The salinity environment can influence male growth rates, e.g. via osmoregulatory costs, which in turn may influence the use of sneaker tactics for small males competing for mating opportunities. Salinity can also affect sperm directly; however, little is known of how salinity influences sneaker tactics through sperm performance. We sampled males of the invasive round goby (Neogobius melanostomus) from two environments, a freshwater river and a brackish estuary. This fish has two male morphs: nest-holding dark males and non-nest-holding light males. We examined the role of water salinity of 0, 8 and 16 on sperm performance and found that in estuarine males, a salinity of 0 reduced sperm velocity compared to a salinity of 8 and 16. Riverine males had low velocity in all salinities. Sperm viability also decreased by over 30 % in 0 salinity, compared to 8 and 16, for fish from both environments. Gobies produce ejaculate contents in specialized glands that could in theory shield sperm in an adverse environment. However, gland contents did not improve sperm performance in our tests. Body mass and age estimates indicate that riverine males invested more in somatic growth compared to estuarine males. Estuarine light morph males had a high enough gonadosomatic index to indicate sneaker tactics. We propose that when sperm performance is low, such as for the riverine males, sneaker tactics are ineffective, and will be selected against or phenotypically suppressed. Instead, we interpret the increased investment in somatic growth found in riverine males as a life-history decision that is advantageous when defending a nest in the next reproductive season.

opencc-zeroMay 2022View details →

Host-parasite interactions between a copepod (Pharodes tortugensis) and small reef-associated gobies (Coryphopterus) in the British Virgin Islands

The effects of parasitic copepods on free-living hosts are infrequently documented, and the copepod Pharodes tortugensis has remained virtually unstudied since described. For the first time, we document its host range in the British Virgin Islands (BVI), the prevalence and intensity of infections on wild hosts, and its impacts on host morphology and performance. Infections were observed on four benthic gobies in the BVI (Coryphopterus glaucofraenum, C. venezuelae, C. dicrus and C. eidolon) but not on other host species previously reported from other parts of the western Atlantic. Infected gobies were widespread in the BVI (detected at 33 of 52 sites, prevalence from 1–25%) but extremely rare elsewhere in the Caribbean (detected at 2 of 16 sites, prevalence <0.006%). As is typical of macroparasite infections, P. tortugensis was over-dispersed in BVI host populations (mean intensity = 4.7, range = 1–17). Infections were most common in juvenile and female hosts, and rarely found in larger male hosts. The copepods attach in the branchial chamber of the goby; female copepods show high attachment fidelity to the ventral surface of the chamber, while male copepods attached most often to the first two gill arches and in the branchial chamber adjacent to the female. Infections caused substantial damage to the host's branchial chamber and gill filaments. Parasitized gobies also had larger livers and smaller gonads than unparasitized individuals of similar length. The changes in organ mass of infected gobies were not sizeable enough to affect total body mass, and host condition (the body-length vs. body-mass relationship) was similar for gobies with and without infections. Parasitized gobies were, however, significantly smaller in body mass at a given age, reflecting slower overall growth. Effects of P. tortugensis on individual hosts were broadly similar to those of other parasitic copepods that infect fish gills and, for unknown reasons, the BVI appears to be a persistent hotspot of infections on these goby hosts.

opencc-zeroJun 2022View details →

Data supporting: Invader at the edge - genomic origins and physiological differences of round gobies across a steep urban salinity gradient

Species invasions are a global problem of increasing concern, especially in highly connected aquatic environments. Despite this, salinity conditions can pose physiological barriers to their spread and understanding them is important for management. In Scandinavia's largest cargo port, the invasive round goby (Neogobius melanostomus), is established across a steep salinity gradient. We used 12 937 SNPs to identify the genetic origin and diversity of three sites along the salinity gradient and round goby from western, central and northern Baltic Sea, as well as north European rivers. Fish from two sites from the extreme ends of the gradient were also acclimated to freshwater and seawater, and tested for respiratory and osmoregulatory physiology. Fish from the high salinity environment in the outer port showed higher genetic diversity, and closer relatedness to the other regions, compared to fish from lower salinity upstream the river. Fish from the high salinity site also had higher maximum metabolic rate, fewer blood cells and lower blood Ca2+. Despite these genotypic and phenotypic differences, salinity acclimation affected fish from both sites in the same way: seawater increased the blood osmolality and Na+ levels, and freshwater increased the levels of the stress hormone cortisol. Our results show genotypic and phenotypic differences over short spatial scales across this steep salinity gradient. These patterns of the physiologically robust round goby are likely driven by multiple introductions into the high salinity site, and a process of sorting, likely based on behaviour or selection, along the gradient. Since this euryhaline fish risks spreading from this area, seascape genomics and phenotypic characterisation can inform management strategies even within an area as small as a coastal harbour inlet.

opencc-zeroAug 2022View details →

Data for: Differential habitat use of a notorious invasive fish, the round goby, in a translocation-relevant system

Anthropogenic structures can form novel ecosystem niches. Invasive species are often particularly successful in occupying these habitats and utilize them as beachheads for further spread. The invasive round goby (Neogobius melanostomus, Pallas 1814), an inherently bottom-dwelling fish, uses vertical harbour walls as habitat, enabling them to reach boats (i.e. potential translocation vectors). To evaluate the relevance of vertical habitat use for population dynamics and translocation, we exemplary investigated a population of round gobies in a harbour ecosystem. Specifically, we investigated differences in trophic niche characteristics, individual trophic specialization, phenotypic traits, and breeding frequency in wall versus bottom dwelling round gobies. Habitat-characteristic dietary signatures indicated habitat partitioning during the breeding season. Trophic niches overlapped but were clearly distinguishable between the habitats: walls were inhabited by 1.4 times more trophic generalists than specialists, while the bottom was inhabited by 2.1 times more trophic specialists. Breeding frequency was 24 times higher on the walls than on the bottom. After the reproductive season, we found a higher similarity in trophic ecology of gobies inhabiting the two habitats, and differences in abundance, size, and condition. These results are in line with winter migrations to deeper habitats, which are common in round gobies in lentic and marine ecosystems. Our results suggest a high potential for microgeographic adaptation to either horizontal or vertical habitat use in invasive round gobies. We demonstrated that male gobies using the walls during the breeding season are larger and heavier, suggesting that wall-climbing may select for more competitive individuals. Additionally, the overall abundance of round gobies likely increases with the additional use of vertical habitat space, which may lead to higher propagule pressure. The ability to exploit anthropogenic habitats, and a higher translocation probability of competitive individuals, can contribute to the invasion success of round gobies in anthropogenically influenced aquatic systems.

opencc-by-4.0Aug 2022View details →

Observation data of a PV site and a Gobi site

This is a supplementary file for the submitted paper "The characteristics and parameterizations of the surface albedo of utility-scale photovoltaic plant in the Gobi Desert".

opencc-by-4.0Feb 2024View details →

Fig. 5 in The black goby Gobius niger Linnaeus, 1758 in the Marchica Lagoon (Alboran Sea, Morocco): spatio-temporal distribution, its environmental drivers, and the site-related footprint

Fig. 5: Spatial and temporal distribution of Gobius niger in the Marchica Lagoon.

opencc-by-4.0Dec 2021View details →

Figure 1 in DNA barcoding of two amphidromous goby postlarvae ('penja') morphotypes from Mandar River, West Sulawesi, Indonesia

Figure 1. – Map of West Sulawesi showing the Mandar River and the study site.

opencc-by-4.0Feb 2018View details →

Figure 2 in First record of round goby Neogobius melanostomus Pallas, 1814 (Pisces: Gobiidae) in Bosnia and Herzegovina

Figure 2. Neogobius melanostomus from Una river.

Fig. 3 in Comparative Analysis of Complete Mitogenomes of Two Gobies and Their Phylogenetic Implication.

Fig. 3. Relative synonymous codon usage of Protein-coding genes in Oxyurichthys ophthalmonema.

Fig. 2 in Comparative Analysis of Complete Mitogenomes of Two Gobies and Their Phylogenetic Implication.

Fig. 2. Gene map of Oxyurichthys microlepis mitogenome.

Fig. 1 in Comparative Analysis of Complete Mitogenomes of Two Gobies and Their Phylogenetic Implication.

Fig. 1. Gene map of Oxyurichthys ophthalmonema mitogenome.

Fig. 4 in Comparative Analysis of Complete Mitogenomes of Two Gobies and Their Phylogenetic Implication.

Fig. 4. Relative synonymous codon usage of Protein-coding genes in Oxyurichthys microlepis.

opencc-by-4.0Dec 2018View details →

Figure 2 in Selectivity on epilithic diatom consumption for two tropical sympatric gobies: Sicydium punctatum Perugia, 1986 and Sicydium plumieri (Bloch, 1786)

Figure 2. – Sicydium plumieri (A) and Sicydium punctatum (B). Pictures and copyright Erick Vigneux.

opencc-by-4.0Dec 2018View details →

Figure 1 in Selectivity on epilithic diatom consumption for two tropical sympatric gobies: Sicydium punctatum Perugia, 1986 and Sicydium plumieri (Bloch, 1786)

Figure 1. – Locations of the upstream and downstream sampling sites.

opencc-by-4.0Nov 2014View details →

Fig. 9 in Mugilogobius hitam, a new species of freshwater goby (Teleostei: Gobioidei: Gobiidae) from Lake Towuti, central Sulawesi, Indonesia

Fig. 9. Mugilogobius hitam, new species, captive specimen (photograph by H.-G. Evers).