scholarly journals Ecomorphology and resource use by dominant species of tropical estuarine juvenile fishes

2015 ◽  
Vol 13 (2) ◽  
pp. 401-412 ◽  
Author(s):  
André Luiz Machado Pessanha ◽  
Francisco Gerson Araújo ◽  
Ronnie Enderson M. C. C. Oliveira ◽  
Adna Ferreira da Silva ◽  
Natalice Santos Sales

Eleven ecomorphological attributes and diet of seventeen juvenile fish species were examined to test the hypothesis that morphological patterns determine resource uses in estuarine habitats. Species were separated according to the apparatus to food capture and habitat use (benthic or pelagic) in three different groups: (1) a group with depressed fish body, strong caudal peduncle and enlarged pectoral fins; (2) a second group laterally flattened with a wide protruding mouth, and (3) a third group strongly flattened with small pectorals fins. The following six trophic groups were organized based on prey categories: Zooplanktivores, Benthivores, Omnivores, Detritivores, Macrocarnivores and Insectivores. Significant results (PERMANOVA) between ecomorphological indices and habitat and between ecomorphological indices and trophic groups were found. These data indicate that similarity of ecomorphological forms, which minimize the influence of environment and partitioning of food, would help facilitate the co-existence of these fish when they are abundant in this tropical estuary.

2020 ◽  
Vol 23 (1) ◽  
Author(s):  
Se Hun Myoung ◽  
Seok Nam Kwak ◽  
Jin-Koo Kim ◽  
Won-Chan Lee ◽  
Jeong Bae Kim ◽  
...  

AbstractAssemblages of juvenile fish and associated abiotic parameters were investigated inside and outside Jinju Bay in southern Korea, on a monthly basis from December 2014 to November 2015. Fluctuations in water temperature and salinity were larger inside than outside the bay. In total, 534,657 individuals per square kilometre from 81 fish species and 47 families were collected during the study period. The most dominant species was Nuchequula nuchalis both inside (25.6%) and outside (26.9%) the bay. The next dominant species were Thryssa kammalensis (17.9%) and Zoarces gillii (16.0%) inside the bay and Liparis tanakae (16.9%) and T. kammalensis (9.0%) outside the bay. Forty species (33% of total number of individuals) of young fish were recorded inside the bay and 47 species (52%) outside the bay. Therefore, it appears that a diversity of fish use nursery grounds inside and outside Jinju Bay. In particular, the following six species appeared: Z. gillii, Pleuronichthys cornutus, L. tanakae, Hemitripterus villosus, Pennahia argentata, and Xenocephalus elongates. Due to assemblage differences for fishes within Jinju Bay and outside the bay, management of both areas is required to maintain current diversity of species in the region.


Author(s):  
K. Hushtan

The peculiarities of biotope differentiation of amphibiotic insects ecomorphs spectra (Insecta: Ephemeroptera, Plecoptera, Odonata) in hydroecosystems of Ukrainian Carpathians are established. Among Ephemeroptera ecomorphs, the dominant species (in the number of species) were: subclass ploskotili velykoziabrovi zbyrachi-ziskobliuvachi ta khyzhaky; subclass siflonuroidni dribno ziabrovi zbyrachi-ziskobliuvachi. For epirytral, the dominant ecomorphs among the freckles are kryptobionty shchilyn briofily (35%); for metarytral – fitofilni kryptobionty podribniuvachi (61%); litofilni kryptobionty, yaki poliuiut iz zasidky (71%) – predominate in hiporytral. The spatial distribution of ecomorph groups of mayflies and stoneflies in Ukrainian Carpathians is subject to the general tendencies of vertical zonal distribution of trophic groups of zoobenthos, and is consistent with the basic provisions of the theory of river continuum of R. Vannot.


Author(s):  
José Amorim Reis-Filho ◽  
Francisco Barros ◽  
José De Anchieta Cintra Da Costa Nunes ◽  
Cláudio Luis Santos Sampaio ◽  
Gabriel Barros Gonçalves De Souza

The influence of the lunar phases and tidal range on the fish capture was analysed in a tidal flat in Barra do Paraguaçu (Baía de Todos os Santos). The sampling was realized in the flood tide and ebb tide of the spring (full moon) and neap (waning moon) tides, between June 2007 and May 2008. At all sampling occasions, two parallel drags were accomplished to the tidal flat, in the same direction of the current, in a 100 m long area marked on the beach beforehand, using a seine net of 15 m × 2.0 m with a mesh of 12 mm between adjacent knots. A total of 2312 fish specimens were captured (26.5 kg), belonging to 75 species from 45 families. The mean number of captured fish was significantly larger in full moon at ebb tides, while the mean weight in the captures was larger in ebb tides. There was significant difference in number of species, number of fish, richness and diversity between full and waning moons. The number of fish and biomass were significantly different between tides. Significant differences were found in community structure regarding trophic groups in relation to tide and moon, although the classic diversity indices did not capture this effect between tides. Furthermore, it was possible to identify preferences of occurrence related to the change of tide in dominant species.


2018 ◽  
Vol 101 (10) ◽  
pp. 1427-1442 ◽  
Author(s):  
Rayssa Soares da Silva ◽  
Alexandra Sofia Baptista Vicente Baeta ◽  
André Luiz Machado Pessanha

2010 ◽  
Vol 55 (3) ◽  
Author(s):  
Adriana García-Vásquez ◽  
Haakon Hansen ◽  
Kevin Christison ◽  
Miquel Rubio-Godoy ◽  
James Bron ◽  
...  

AbstractGyrodactylus infections in intensively-reared populations of Nile tilapia, Oreochromis niloticus niloticus, have been associated world-wide with high mortalities of juvenile fish. In this study, 26 populations of Gyrodactylus parasitising either O. n. niloticus or Mozambique tilapia, Oreochromis mossambicus, were sampled from fourteen countries and compared with type material of Gyrodactylus cichlidarum Paperna, 1968, Gyrodactylus niloticus (syn. of G. cichlidarum) and Gyrodactylus shariffi Cone, Arthur et Bondad-Reantaso, 1995. Representative specimens from each population were bisected, each half being used for morphological and molecular analyses. Principal component analyses (PCA) identified five distinct clusters: (1) a cluster representing G. cichlidarum collected from O. n. niloticus from 13 countries; (2) the G. shariffi paratype; (3) three specimens with pronounced ventral bar processes collected from two populations of Mexican O. n. niloticus (Gyrodactylus sp. 1); (4) four specimens collected from an Ethiopian population nominally identified as O. n. niloticus (Gyrodactylus sp. 2); (5) nine gyrodactylids from South African O. mossambicus (Gyrodactylus sp. 3). Molecular analyses comparing the sequence of the ribosomal transcribed spacer regions (ITS 1 and 2) and the 5.8S gene from the non-hook bearing half of worms representative for each population and for each cluster of parasites, confirmed the presence of G. cichlidarum in most samples analysed. Molecular data also confirmed that the DNA sequence of Gyrodactylus sp. 2 and Gyrodactylus sp. 3 (the morphologically-cryptic group of South African specimens from O. mossambicus) differed from that of G. cichlidarum and therefore represent new species; no sequences were obtained from Gyrodactylus sp. 1. The current study demonstrates that G. cichlidarum is the dominant species infecting O. n. niloticus, being found in 13 of the 15 countries sampled.


2005 ◽  
Vol 3 (3) ◽  
pp. 389-394 ◽  
Author(s):  
Vinicius A. Bertaco ◽  
Paulo H. F. Lucinda

A new characid species, Astyanax elachylepis, is described from the rio Tocantins drainage. The new species is distinguished from its congeners by possessing 48-53 perforated scales along the lateral line, a large caudal-peduncle spot, the presence of bony hooks on dorsal, anal, pelvic, and pectoral fins of males, one or two vertically-elongated humeral spots, one maxillary tooth, and 22-27 branched anal-fin rays.


Author(s):  
Lilly Aprilya Pregiwati ◽  
Budy Wiryawan ◽  
Sugeng Hari Wisudo ◽  
Arif Satria

<div class="WordSection1"><p class="ABSTRACT">ABSTRACT</p><p class="Abstractisi">Rumpon or Fish Aggregating Devices (FADs) had been used by purse seine and handline fishermen in Pacitan Regency since 2005. The use of rumpon has been associated with the catching of immature fishes in large number that would disrupt the sustainability of fish resources.  The aims of this study were to measure fishing productivity of purse seine and handline fleets operated around FADs deployed in eastern Indian Ocean waters and analyze the size distribution and gonad maturity index of the catch. This study was conducted at Tamperan Fishing Port of the Pacitan Regency, East Java Province. Daily fish landing data from both fishing fleets were collected from the Tamperan auction hall from January to December 2014 for productivity calculation. About 289 fish samples from 6 dominant species was taken randomly on-board of 3 purse seine and 2 handlines vessels from 8 different FADs for size distribution and gonad analysis. The average productivity of purse seine fleets in 2014were 6,7 tonnes/trip (s = 5 tonnes/trip) while handling fleets average productivity were 0,9 tons/trip (s = 0,6 tons/trip. Purse seine catch were dominated by immature and juvenile fish while handlines catch were larger and already mature fishes.</p><p class="Abstractisi"><strong>Keywords</strong>:FADs, fishing productivity, gonad analysis</p><p align="center"><strong>ABSTRAK </strong></p><p>Rumpon atau <em>Fish Aggregating Devices</em> (<em>FADs</em>) telah digunakan oleh nelayan pukat cincin dan pancing ulur di Kabupaten Pacitan sejak tahun 2005. Penggunaan rumpon seringkali dihubungkan dengan penangkapan ikan yang belum dewasa dalam jumlah yang terlalu banyak sehingga dapat mengganggu keberlanjutan sumber daya ikan.  Penelitian ini bertujuan untuk menghitung produktivitas alat tangkap pukat cincin dan pancing ulur yang dioperasikan dengan menggunakan alat bantu rumpon yang dipasang di Samudera Hindia bagian timur dan menganalisis ukuran dan tingkat kematangan gonad hasil tangkapannya. Penelitian ini dilaksanakan di Pelabuhan Perikanan Tamperan, Kabupaten Pacitan, Propinsi Jawa Timur. Data pendaratan ikan harian selama bulan Januari hingga Desember 2014 diperoleh dari unit pelaksana teknis tempat pelelangan ikan Tamperan untuk perhitungan produktivitas.  Adapun sampel ikan sebanyak 289 ekor diambil dari 3 unit kapal pukat cincin dan 2 unit kapal pancing ulur yang beroperasi di 8 rumpon yang berbeda untuk analisis sebaran ukuran dan tingkat kematangan gonad ikan hasil tangkapan. Produktivitas rata-rata pada tahun 2014 untuk alat tangkap pukat cincin yaitu sebesar 6,7 ton/trip (<em>s</em> = 5 ton/trip), sedangkan pancing ulur yaitu sebesar 0,9 ton/trip (<em>s</em> = 0,6 ton/trip). Hasil tangkapan pukat cincin didominasi oleh ikan berukuran kecil dan belum dewasa, sedangkan pancing ulur menangkap ikan yang berukuran lebih besar dan telah dewasa.</p><p>Kata kunci: rumpon, produktivitas penangkapan, analisis gonad</p></div>


2019 ◽  
Vol 116 (37) ◽  
pp. 18466-18472 ◽  
Author(s):  
Marcelo Magioli ◽  
Marcelo Zacharias Moreira ◽  
Renata Cristina Batista Fonseca ◽  
Milton Cezar Ribeiro ◽  
Márcia Gonçalves Rodrigues ◽  
...  

The broad negative consequences of habitat degradation on biodiversity have been studied, but the complex effects of natural–agricultural landscape matrices remain poorly understood. Here we used stable carbon and nitrogen isotopes to detect changes in mammal resource and habitat use and trophic structure between preserved areas and human-modified landscapes (HMLs) in a biodiversity hot spot in South America. We classified mammals into trophic guilds and compared resource use (in terms of C3- and C4-derived carbon), isotopic niches, and trophic structure across the 2 systems. In HMLs, approximately one-third of individuals fed exclusively on items from the agricultural matrix (C4), while in preserved areas, ∼68% depended on forest remnant resources (C3). Herbivores, omnivores, and carnivores were the guilds that most incorporated C4carbon in HMLs. Frugivores maintained the same resource use between systems (C3resources), while insectivores showed no significant difference. All guilds in HMLs except insectivores presented larger isotopic niches than those in preserved areas. We observed a complex trophic structure in preserved areas, with increasing δ15N values from herbivores to insectivores and carnivores, differing from that in HMLs. This difference is partially explained by species loss and turnover and mainly by the behavioral plasticity of resilient species that use nitrogen-enriched food items. We concluded that the landscape cannot be seen as a habitat/nonhabitat dichotomy because the agricultural landscape matrix in HMLs provides mammal habitat and opportunities for food acquisition. Thus, favorable management of the agricultural matrix and slowing the conversion of forests to agriculture are important for conservation in this region.


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