Asian green mussel is commercially farmed in tidal waters in several enclosed bays in Sabah, Malaysia. In this study, two areas on the west coast of Sabah – Ambong Bay and Marudu Bay – were selected ...for the monitoring of the growth and mortality rates of green mussels farmed in suspension raft. Both growth and survival rates were then correlated with physicochemical parameters (dissolved oxygen, pH, salinity, temperature, water transparency, chlorophyll-
), nutrients (phosphate (PO
), ammonia (NH
-N), nitrate (NO
-N) and nitrite (NO
-N) and condition index of mussel from each study site, as well as between the study sites. The twelve-month growth study (September 2017 to August 2018) was started with a total of 180 mussel specimens (90 at each site). The initial size (mean) of the mussel seed used was 47.7 ± 3.5 mm and 51.1 ± 3.9 mm for Marudu Bay and Ambong Bay, respectively. Mussels in Marudu Bay attained mean size of 73.47 ± 11.05 mm (SGR 0.17% ± 0.22) compared to 64.05 ± 7.44 mm (SGR 0.11% ± 0.22) for Ambong Bay at the end of the experiment. The cumulative mortality rates were 9.2% ± 4.9 and 55.5% ± 30.0 for Marudu Bay and Ambong Bay, respectively. The Pearson correlation indicated a significant positive relationship between mortality and water transparency (r = 0.684, p<0.01). There was a significant negative relationship between ammonia in seawater and mussel mortality (r = -0.561, p<0.01), as well as significant negative relationships between nitrate and growth (r = -0.480, p<0.05) and mortality (r = -0.460, p<0.05), as indicated by Spearman’s Rank-order Correlation analysis. Overall, the growth performance of green mussels farmed in Marudu Bay was better than in Ambong Bay, however, the mortality of mussels in Ambong Bay was higher.
Ng CKC, Abdullah F, Biun H, Ibrahim MK, Mustapha S, Sade A. 2017. Review: A working checklist of the freshwater fish diversity for habitat management and conservation work in Sabah, Malaysia, North ...Borneo. Biodiversitas 18: 560-574. Prioritization of freshwater habitat management and conservation is dependent on the availability of species baseline information at regional level. However, such information has not been updated since 2002 in Sabah. Thus the objective of this paper is to present the latest working checklist of freshwater ichthyofauna known so far in the state. A literature review of 68 studies was conducted focusing on the latest valid binomial nomenclature, locality and conservation status. A total of 166 valid species, namely 150 native species and 16 introduced species, were deduced from the literature. Native species comprised of 10 orders, 27 families and 75 genera while introduced species were from four orders, seven families and 14 genera. The review revealed 103 species (68.6% of native species) were yet to be assessed for the IUCN Red List and 11 species (7.3%) were identified as Data Deficient by IUCN. Some taxonomic discrepancies were also found and discussed. Many areas in Sabah remain poorly inventoried due to unequal sampling effort, biophysical and cultural challenges. The species list proposed herein is tentative at best and the number of species is expected to increase as more surveys are conducted in the near future.
Azijski zeleni školjkaš komercijalno se uzgaja u plimnim vodama nekoliko zatvorenih uvala u državi Sabah u Maleziji. U ovom su istraživanju dva područja na zapadnoj obali Sabaha - zaljev Ambong i ...zaljev Marudu - odabrana za praćenje rasta i mortaliteta zelenih dagnji uzgajanih na visećim strukturama splava. Stopa rasta i preživljavanja su nadalje povezane s fizikalno-kemijskim parametrima (otopljeni kisik, pH, slanost, temperatura, prozirnost vode, klorofil - a), hranjivim tvarima (fosfat (PO 3-), amonijakom (NH -N), nitratima (NO -N) nitritima (NO -N) te indeksom kondicije dagnji iz svakog od područjaispitivanja, kao i između područja. Dvanaestomjesečna studija rasta (rujan 2017. - kolovoz 2018.) započeta je s ukupno 180 uzoraka školjkaša (90 na svakom području/ lokaciji). Početna prosječna dužina korištenog nasada školjkaša bila je 47,7 ± 3,5 mm za zaljev Marudu te 51,1 ± 3,9 mm za zaljev Ambong. Na kraju eksperimenta, dagnje u zaljevu Marudu postigle su prosječnu dužinu od 73,47± 11,05 mm (SGR 0,17% ± 0,22) u usporedbi sa 64,05 ± 7,44 mm (SGR 0,11% ± 0,22) za zaljev Ambong. Stopa kumulativnog mortaliteta iznosila je 9,2% ± 4,9 za zaljev Marudu te 55,5% ± 30,0 za zaljev Ambong. Pearsonova korelacija ukazala je na značajan pozitivan odnos između mortaliteta i prozirnosti vode (r = 0,684, p<0,01). Postojala je i značajna negativna veza između amonijaka u morskoj vodi i mortaliteta školjkaša (r = -0,561, p<0,01), kao i značajne negativne veze između nitrata i rasta (r =-0,480, p<0,05) te mortaliteta (r = - 0,460, p<0,05), na što je ukazala Spearmanova korelacijska analiza. Općenito, rezultati ukazuju na bolji rast uzgajanih zelenih dagnji u zaljevu Marudu nego u zaljevu Ambong. Također, dagnje iz zaljeva Ambong imale su viši mortalitet.
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