Demographic and Life History Characteristics of Black Bullheads Ameiurus melas in a North Temperate USA Lake

Black bullheads Ameiurus melas are an environmentally tolerant omnivorous fish species that are found throughout much of North America and parts of Europe. Despite their prevalence, black bullheads are an infrequently studied species making their biology, ecology, and life history poorly understood. Although limited information has been published on black bullheads, evidence suggests that bullheads can dominate the fish biomass and have profound influences on the fish community in some north temperate USA lakes. The goal of our study was to provide additional information on black bullhead population demographics, growth rates, life history characteristics, and seasonal diet preferences in a northern Wisconsin lake. Using common fish collection gears (fyke netting, electrofishing), fish aging protocols, fecundity assessments, and diet indices, our results suggested that black bullheads exhibited relatively fast growth rates, early ages at maturity, moderate fecundity, and a diverse omnivorous diet. Due to these demographic and life history characteristics, black bullheads have the potential to dominate fish community biomass in their native and introduced range. Results from our study may inform the management of black bullhead as native and invasive species.

Preferensi Habitat Ikan Gabus [Channa striata (Bloch 1793)] di Perairan Rawa Aopa, Sulawesi Tenggara

The use of habitat by fish is closely related to efforts to find the best conditions for the survival of these fish. This study aims to analyze the habitat preferences of Striped snakehead in Rawa Aopa waters, Southeast Sulawesi. This research was conducted from November 2018 to February 2019 in the waters of Swamp Aopa Southeast Sulawesi. Fish collection using traps. The constancy and fidelity index determined the preference of striped snakehead for habitat type. A total of 1024 striped snakehead fish were caught during the study with a length range of 200,0-420,0 mm and 69,0-596,0 g weight. Striped snakehead measuring 200-367 mm were consistent in occupying habitats with a slightly dense to dense water plant density, while sizes 368-388 and 389-430 mm were consistent in habitats with sparse water plant density. The preference level of striped snakehead fish size 389-430 mm to habitats with rare aquatic plants is very high (Fij = 6). Therefore, the size can be used as an indicator of habitats with the rare aquatic plant category. The preference for 200-367 mm striped snakehead fish in dense aquatic plant habitats indicates that these habitats are foraging, growing, and protective zones. Keywords: Channa striata, fish habitat, Rawa Aopa, Southeast Sulawesi, stripe snakehead

Taxonomy of the genus Dactylanthias Bleeker (Teleostei: Serranidae: Anthiadinae)

The anthiadine genus Dactylanthias is reviewed. Two species, Dactylanthias aplodactylus (Bleeker, 1858) and Dactylanthias baccheti Randall, 2007 are currently recognised, each known only from their holotypes. A specimen of Dactylanthias matching D. baccheti in coloration was recently collected from Nauru in the West Pacific Ocean. It was retained by a recreational fisher and deposited into the CSIRO Australian National Fish Collection, Hobart. Data collected from this specimen and comparison to images of and data from the holotypes of both nominal species indicate that Dactylanthias baccheti Randall, 2007 is a junior synonym of Dactylanthias aplodactylus (Bleeker, 1858). Additional records of specimens from Ambon, Indonesia (type locality of D. apolodactylus) and the Maldives Islands, Indian Ocean are reported. The genus is briefly compared with other anthiadine genera.

Ichthyofauna of Fakfak, Papua – Indonesia

Fakfak and Kumawa Mountains are located in Bomberay Peninsula, Papua, a poorly known ichthyological record and was recommended by Conservation International for field inventory. This research was conducted from 6-15 February 2021 to document freshwater fish diversity in northern and eastern Fakfak toward Bomberay District. The fish was collected from creeks, streams, and rivers. The fish collection was done once in each location, mainly using a seine net, while a gill net was used in a few sites along Ubadari River. It was done for four hours, netting in one to three locations each day. Fish abundance was described based on common (C), occasionally (O), dan rare (R) scales. Freshwater fish data were descriptively identified. Twenty-two native New Guinean species belonging to 19 genera and 14 families were collected during the survey. There was no specific family dominant in the fish community. All fish recorded have widespread distribution, yet only one species has restricted distribution in the Vogelkop and Bomberay Peninsulas. One rainbowfish species was observed but not properly identified. This results as initial data of the fish community of Bomberay Peninsula, especially of Fakfak. Further research is needed to reveal the fish community from another part of the peninsula.

Macrophytes banks as potential fish nursery areas in small hydropower reservoirs

Aim This study verified if the macrophyte banks found in two reservoirs of small hydroelectric plants (SHPs) have a functional ecological role for the initial development of ichthyofauna. Additionally, we compared the differences in the structure of the fish assemblages along each reservoir compartment and between reservoirs. Methods Sampling was performed in March 2018, in lotic, intermediate, and lentic compartments of Palmeiras and Retiro reservoirs, Sapucaí-Mirim River (SP). Three distinct macrophyte banks in each stretch (triplicates), considering the most representative in terms of composition (recurrency/dominance), were sampled, resulting in 18 samples (nine per reservoir). For fish collection we used a sieve of 1 m2 of area, mesh size of 1 mm, which was manually hauled, from the boat, in the marginal aquatic vegetation (three hauls per sample). Simultaneously, we measured basic limnological parameters with a Horiba U-52 water probe, adjacent to the banks. Results The presence of juveniles of all fish orders found in the river, Characiformes, Siluriformes, Synbranchiformes, Gymnotiformes and Cichliformes, demonstrates that, at least in certain moment of their development cycle, the macrophyte banks are used by species with different ecological requirements. It was observed significant statistical differences in the structure of the ichthyofauna along the longitudinal axes of the reservoirs, but not between reservoirs. The same was seen for the limnological data (PCA). Conclusions The macrophyte banks found in the SHPs reservoirs have a potential role as nurseries for the local ichthyofauna, mainly, but not exclusively, for sedentary species and with parental care. This association is ecologically relevant, given the absence of typical lateral habitats for the initial development of the fish fauna. Additionally, despite the reservoirs small size, spatial organization was also important for the assemblage’s structure, with differences in terms of composition, size and development stages along the distinct sampling stretches.

TRAFFICKING OF ORNAMENTAL FISH IN THE BRAZILIAN AMAZON

The trafficking of ornamental fish is growing on a yearly basis in the Brazilian Amazon. This represents a serious threat to the biodiversity of the region. The objective of this research was to evaluate the trafficking of ornamental fish in the Brazilian Amazon using data from the seizures by the Federal Police and Brazilian Institute of Environment and Renewable Natural Resources - IBAMA. To assess and quantify this illegal trade, we gathered data relating to the period between January 2003 and January 2020. Information was obtained from IBAMA - Amazon - regional superintendence; National Amazon Research Institute - INPA regarding smuggled species that have been recovered and placed in its fish collection. The results show that in 98 seizures made by IBAMA, a total of 170,849 specimens of at least 73 species of 10 families, and 5 orders were recovered. Most of the illegally trafficked species are from the Loricariidae family (31 species, 8.47%). Hypancistrus zebra (Loricariidae), Potamotrygon jabuti, Potamotrygon leopoldi (Potamotrygonidae), Osteoglossum bicirrhosum and Osteoglossum ferreirai (Osteoglossidae) are the most targeted by the traffickers, due to their high value. At least 12 species are undescribed new species and were registered and placed in INPA’s fish collection. The fish followed different routes to reach the border that Brazil, Colombia, and Peru share. We conclude that in order to fight this illegal trade, tougher laws against smugglers, agreements with neighboring countries to combat trafficking, formal environmental education programs for riverine populations, and further scientific studies of smuggled species are necessary.

The length-weight relationship and condition factor of Toothpony (Gazza minuta Bloch, 1795) from Pabean Bay, Indramayu, West Java

The purpose of this study is to specify the length-weight relationship and to evaluate the relative condition factor of toothpony (Gazza minuta Bloch 1795) in Pabean Bay, Indramayu, West Java. The fish collection was carried out monthly from January 2016 to December 2016, and a total of 190 individual fishes were caught using gillnet with mesh sizes varying from 1 to 2 inches. The fish samples ranged from 30 – 138mm in length and 0.41 – 35.83 g in weight. The length-weight relationship was W= 1.51 10-4 L2.388, and the condition factors of fish varied from 1.1 ± 0.22 to 2.03 ± 2.29. These results indicate that the growth pattern of toothpony (Gazza minuta Bloch 1795) in Pabean Bay was allometric negative.