Sustainable Aquatic Research

Where Have All the Good Editors Gone? - A Necessary Polemic

2024-03-17T20:29:58+03:00

In the new age, where a certain political elite has made alternative facts and fake news acceptable to the public, it is not surprising that strange papers appear even in highly ranked aquaculture journals: articles with fake bibliographies or missing or at least very poor identification of the organisms studied. They appear without any sanction or commentary and even pretend to be peer-reviewed. Who knows if results or even entire articles are homemade? Can we be sure that results or even entire articles are not just fabricated fairytales? Is it of any surprise that Open Access (OA) journals, including those from major publishers, do not fight these tendencies? Earning article processing charges appears to counts more than science! Where have all the good scientific editors gone?

Particle selectivity based on pre-ingested phytoplankton composition in Charru Mussel Mytella strigata (Hanley, 1843)

2023-12-22T14:19:20+03:00

Identification of phytoplankton trapped in the gills suggests initial selectivity and food preference in marine bivalve molluscs. In this study, pre-ingested phytoplankton in the gills of Mytella strigata were determined and compared to the existing phytoplankton in the waters of three sites in the Philippines (Pangasinan, Cavite, and Bataan). Pre-ingested phytoplankton of M. strigata varied with size (p<0.05) and site (p<0.05). Coscinodiscus spp. and Skeletonema spp. were most abundant across sizes (<20mm, 20–40mm, and >40mm) and sites. Particle selection observed in the gills suggests food preference for centric diatoms such as Coscinodiscus spp., Skeletonema spp., and Navicula spp. The ingestion of these diatoms ranged from 26% to 46% of the total phytoplankton composition in the waters of different sites. The results highlight particle selection during filtration and indicate a potential food preference of M. strigata.

Investigations on the phytoplankton composition and trophic status of Lake Karagöl (Dikili-İzmir-Türkiye)

2024-03-12T15:41:58+03:00

Abstract

The phytoplankton composition, TN:TP ratios as the limiting factor on phytoplankton and the trophic Status of Lake Karagöl, a small volcanic-originated lake, were first investigated in this study. Additionally, the physicochemical parameters of the lake were measured. As a result of the investigations, 21 dominant taxa from four divisions among phytoplanktonic organisms were identified in Karagöl. Three taxa belonged to Cyanobacteria, eleven to Chlorophyta, six to Ochrophyta (only Bacillariophycea), and to one to Myzozoa. The average depth of the lake was calculated as 8.7 m. In line with the atmospheric temperatures brought by the Mediterranean climate prevailing in the region, surface water temperatures of the lake fluctuated between 23.0 °C (summer) and 6.5 °C (winter). Conductivity ranged from 780 to 423 µS and dissolved oxygen ranged from 15.3 to 7.3 mg l^-1. The average scores of TSI (SD), TSI (Chl-a), TSI (TN) and TSI (TP) were calculated as 68.0, 55.1, 62.1 and 86.4 respectively. These TSI scores indicated that Lake Karagöl was at eutrophic or hypereutrophic levels. TN:TP ratio of the lake ranged from 9.8 to 7.2 and in this case, the Lake Karagöl food chain is nitrogen-limited because of the low TN:TP ratios. Dolichospermum flosaquae (N2-fixing heterocystous Cyanobacteria) was the dominant species in Lake Karagöl phytoplankton during the summer months when the high-water temperature. As a result of this study, based on phytoplankton composition, dominant algae groups (especially Cyanobacteria) and TSI scores, it was evaluated that Lake Karagöl (Dikili) has suitable environmental conditions for many algae species found in mesotrophic and eutrophic lakes and is in a very rapidly progressing hypertrophication process.

Integrated multitrophic aquaculture of sandfish (Holothuria scabra) with marine water acclimatized Nile tilapia (Oreochromis niloticus) and oyster (Sacostrea cucullata) for increased production in Kenya

2024-04-18T00:45:30+03:00

This study compared the growth performance, production, and quality of culture environment of integrated multitrophic aquaculture (IMTA) systems with different species combinations in earthen ponds. The experiment was designed to assess the viability of using marine water acclimatized Nile tilapia (Oreochromis niloticus) as the fed component of the IMTA system in combination with sea cucumbers (Holothuria scabra) and Oysters (Sacostrea cucullata) as extractive species. The control (C) experiment and had a monoculture of O. niloticus. Treatment 1 (T1) had a combination of O. niloticus and H. scabra. Treatment 2 (T2) had a combination of O. niloticus, H. scabra and S. cucullata and Treatment 3 (T3) had a combination of O. niloticus and S. cucullata. Stocking was 2 ind./m², 1.9 ind./m² and 2.1 ind./m² for tilapia, sea cucumber and oysters respectively and replicated in all the treatments. During the 150 days culture period, S. cucullata attained weight gain of 23.74 ± 2.6 g and 26.55 ± 0.26 g in T2 and T3 respectively. Weight gain of H. scabra in T1 and T2 was 146.7 ± 6 g and 153.39 ± 2.04 g respectively. The final average body weight (ABW) of the fed species O. niloticus was significantly higher (p < 0.05) in T2 at 218.82 ± 1.55 which had all the three species combinations. The findings of the study show that the IMTA that had a combination of all three species outperformed those that had two species.

Phytoplankton-periphyton orientation influences feeding behavior of cultivable species: A case study on rohu, Labeo rohita (Hamilton, 1822)

2024-03-11T13:53:30+03:00

The Indian Major Carp, Labeo rohita was stocked in four different resource environments namely, Periphyton monoculture, Periphyton polyculture, Plankton monoculture, and Plankton polyculture. Bamboo substrates were used as periphyton colonizers in culture ponds. In polyculture stocks, the Catla catla and Cirhinus mrigala were used as companion crop. The on-farm experiment was conducted for 210 days, and gut contents of rohu were collected and analyzed throughout the stocking period. The gut abundances of rohu showed an inclination towards algal food organisms, especially Cyanophyceae, Chlorophyceae, Baccillariophyceae, and Eugelophyceae, towards the later period of stocking when the fish attains a considerable total length. Results from the Shanon Diversity index supported higher algal diversity in the fish gut in periphytic conditions. The Diet breadth index also clearly indicated that rohu has a strong preferences towards periphyton than plankton. Such preferences are more prevalent in polyculture than in monoculture conditions. In conclusion, it can be accepted that rohu has clear preference towards periphyton over plankton when it is available in the environment. Stocking of other planktonic feeders in polyculture conditions may have no impact on the feeding pattern of rohu if periphytic resources are made available in the environment.

Assessment of Benthic Macrofauna and Sediment Characteristics of Boracay Island, Philippines

2023-12-22T14:14:52+03:00

Boracay island is a world-famous beach located in the Philippines. Its beaches are economically important due to its unique “white sand” characteristics popular for swimming and other recreational activities. Studies on macrobenthic organisms present in the area that are ecologically important and may play part in its unique sand, however, are still lacking. This study assessed the diversity, abundance, and distribution of the benthic macrofauna and the characteristics of the sediments in Stations 1, 2, and 3 of Boracay Island. Tide lines from various times of the day: high tide – morning (HTM), low tide (LT), high tide – evening (HTE); and at 0.5m water depth at high tide morning (0.5) was assessed. Overall, there are 474 individuals belonging to 5 classes, 10 families, and 10 genera collected from the three stations. The major taxa groups found are Bivalvia, Gastropoda, Malacostraca, Polychaeta, and Sipuncula. Donax sp. (wedge shell) was the most dominant species in the study area with 266 total individual counts. Among the three stations, Station 1 is the most diverse (H = 1.21) while Station 2 has the most abundant macrofaunal presence (relative abundance = 82.07%). In terms of area, HTE is the most diverse and abundant (H = 0.22; relative abundance = 60.97%). Most of the species found are known to be highly tolerant to a variety of conditions making it easier for them to adapt with less ideal conditions. The Armandia sp., found dominant in the area, is highly sensitive to marine pollution, making it an excellent indicator for future monitoring of Boracay Island.