Arfak rainbow fish, Melanotaenia arfakensis is an endemic fish on several river systems in the northeastern part of the Vogelkop peninsula. This study aims to describe the growth, age at first maturity, and sexual dimorphism of this endemic fish on the Nimbai Stream and the Aimasi Stream, the Prafi River system. The fish were caught using handnet, then were measured their standard length and individual weight. Data were analyzed to estimated growth patterns, von Bertalanffy's growth rate, age at first maturity and sexual dimorphism characteristics. The results showed that male growth patterns varied, with a tendency of the increase in body length faster than that of body weight (negative allometric patterns) with b values ranging from 2.886 to 3.132. On the other hand, the female individuals had positive allometric patterns (b values ranged from 3.062 to 3.378). The growth rate (K) of male body length was faster (0.165-0.174) than that of female individuals (0.159-0.163). Male individuals reached the first maturity condition earlier (at age of 1.83-2.18 years) than female individuals (at age of 2.49-2.64 years). Sexual characteristics between the sexes are related to body height starting to appear when fish are of a standard length of larger than 18.22 mm or when male fish begin to approach the time of the first sexual maturity. Understanding of growth, age, and the characteristics of the sexual dimorphism of endemic fish has an important meaning in monitoring population conditions and for conservation efforts in their natural habitat.
Pasar Sanggeng, pasar Wosi, pelabuhan, PLTD (Pembangkit Listrik Tenaga Disel), perhotelan dan pemukiman penduduk yang terletak di pesisir Teluk Doreri Kota Manokwari, menjadi salah satu pusat aktivitas yang melayani kebutuhan masyarakat. Akibat adanya aktivitas yang tinggi tersebut menyebabkan pembungan sampah-sampah organik dan anorganik tidak terawasi atau terkontrol dengan baik. Kondisi ini berlangsung secara terus menerus setiap hari sehingga dapat menyebabkan terjadi degradasi kualitas perairan. Tujuan Penelitian yaitu untuk mengetahui status kualitas perairan di Teluk Doreri Kabupaten Manokwari. Penelitian dilakukan dari bulan Agustus tahun 2016 bertempat di Laboratorium Kelautan, Ilmu Kelautan Unipa dan Laboratorium Prolink IPB Bogor. Lokasi pengambilan sampel air di sekitar perairan Sawaibu, Wosi, Andai, Sowi dan Perairan Maruni. Data parameter yang diambil melalui pengukuran langsung dan tidak langsung. Pengukuran secara langsung meliputi parameter salinitas, pH, suhu dan oksigen terlarut. Sedangkan pengukuran tidak langsung dengan cara mengambil sampel air. Pengambilan sampel air digunakan untuk penentuan parameter kekeruhan, nitrat, fosfat dan logam berat. Sampel air tersebut langsung dimasukan dalam botol polyetelin dan dikirim ke Prolink IPB Bogor untuk dianalisis. Pengukuran mengacu pada Standard Methods for the Examination of Water and Wastewater (APHA, 1998). Hasil penelitian dari lima lokasi di perairan Teluk Doreri berkisar antara 0,17 – 6,16 NTU untuk kekeruhan, 4,64 – 5,04 untuk pH, 5,1 -6 mg/L untuk oksigen terlarut, 30 – 33 ‰ untuk salinitas, 29, 8 – 30,6 oC untuk suhu air, 0,1 -0,8 mg/L untuk nitrat dan fosfat berkisar 0,08 – 0,16 mg/L. Hasil logam berat cadmium (Cd) menunjukan potensi toksik yang tinggi bagi biota perairan di Teluk Doreri. Parameter logam berat cadmium, nitrat dan fosfat sangat mengkuatirkan serta dapat menyebabkan gangguan terhadap lingkungan khususnya bagi biota perairan. Parameter – parameter tersebut telah melampaui baku mutu yang ditetapkan kementerian lingkungan hidup no 51 tahun 2004.WATER QUALITY IN THE DORERI BAY DISTRICT MANOKWARI. Traditional markets (Pasar Sanggeng and Wosi), port, PLTD (Power Plant), hotels and residential areas are located in the cost of Doreri bay in Manokwari district. Activities in those areas create organic and inorganic wastes that have been used the Doreri bay as a water dump. The waste has been dumped since long time ago and continue up to nowadays. That cause water quality degradation of Doreri bay. The research objective was to determine the status of water quality in Doreri Bay, Manokwari Regency. The water quality study has been carried out in August 2016 in Marine laboratory of UNIPA and Prolink laboratory in IPB. Water samples collected from Sawaibu, Wosi, Andai, Sowi and Maruni beach. Data were divided base on the data collection which is directly and indirectly collected. Water salinity, pH, temperature and dissolved oxygen are direct data collection. Turbidity, nitrate, phosphate and heavy metals are indirect data collection that has been analyzed in Prolink IPB. The water has been analyses by using Standard Method for Examination of Water and Wastewater (APHA, 1998). The results show that turbidity of five areas range from 0.17 to 6.16 NTU, pH range from 4.64 to 5.04, dissolved oxygen between 5.1 -6 mg/L, water salinity range from 30-33%, water temperature between 29, 8 - 30.6 oC, 0.1 -0.8 mg/L for nitrate and phosphate between 0.08 - 0.16 mg/L. Heavy metal (cadmium) showed high potential toxic risk on the biota of Doreri bay. Cadmium, nitrate, and phosphate are a heavy metal that categorized as concerned pollutant to the Dorery bay. Those heavy metal have been exceeded the water quality standard base on Ministry of environment number 51-2004.
The character of Manokwari City’s coastal waters is strongly influenced by activity on the mainland. The degradation in Sawaibu Gulf’s water quality has an impact on water quality nearby, as well as the waters of the Field Work Center (BLK), Lemon Island, and Tanjung Manggewa, which is part of Doreri Gulf. The purpose of this study was to determine the water quality in Doreri Gulf according on location and season. In February-April (rainy season) and August-October (dry season) 2020, the research was carried out within Doreri Gulf, Manokwari, West Papua. Turbidity, salinity, pH, temperature, and dissolved oxygen are amongst the variables analyzed. Its statistical analyses were performed descriptively using standard deviation and ANCOVA to correlate seasons and locations. Temperature, DO, and pH were highest at location 2; salinity showed highest at location 3; and turbidity were highest at location 1. Low concentrations of DO, pH, and salinity were measured at location 1; temperature showed highest at location 3; and turbidity were highest at location 1. The dry season would have the highest temperature, DO, pH, and salinity concentrations, meanwhile the rainy season had enough highest turbidity. The study confirms that there are no variations in water quality between location of each variable and that seasonal factors comprise the majority of differences in water quality.
Abstract. Manangkalangi E, Sembel L, Tebaiy S, Manuputty A, Rumayomi MR, Musyeri P, Sawaki D, Orissu D, Manumpil AW, Kaber Y. 2022. Evaluation of seagrass beds as a foraging and nursery habitat based on the structure of the fish community in Nusmapi Island, West Papua, Indonesia. Biodiversitas 23: 5539-5550. Seagrass beds are one of the ecosystems inhabited by various coastal aquatic fauna, including fish. However, information on the temporal role of this ecosystem for fish fauna, particularly diurnal and nocturnal, is still limited. Therefore, this study was conducted to describe daily variations in the fish species composition, their ecological index, developmental stages, and trophic groups in a seagrass bed on Nusmapi Isl., Manokwari. The species composition differed between day and night sampling periods based on the results obtained from 40 species of fish belonging to 21 families and 7 orders. Furthermore, fish species consisted of three trophic groups (omnivores, carnivores, and herbivores), with omnivores and carnivores dominating during the day and at night by 48.6% and 87.5%, respectively. Species found in seagrass beds majorly consisted of juvenile stage individuals (65.9%). Individual abundance varied from day to night and was mainly found among group-forming species, such as S. spinus, S. trilineata, S. punctatissimum, and M. pralinia. The index of diversity, evenness, and dominance at the two relatively similar sampling times described the overall stability of fish communities in seagrass beds. The results indicate that seagrass beds serve as foraging and nursery grounds for many fish species in coastal waters. In addition, the management and protection of fish biodiversity and coastal fishery resources are affected by the ecosystem function.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.