scholarly journals Stock status of coconut crab (Birgus latro) in Daeo, Morotai Island District, North Maluku, Indonesia

2021 ◽  
Vol 22 (2) ◽  
Author(s):  
Rugaya Serosero ◽  
SULISTIONO SULISTIONO ◽  
NURLISA A. BUTET ◽  
ETTY RIANI
Keyword(s):  
Data Analysis ◽  
Confidence Interval ◽  
Population Size ◽  
Growth Parameters ◽  
Human Consumption ◽  
Length Frequency ◽  
Growth Coefficient ◽  
Male And Female ◽  
Stock Status ◽  
The Status

Abstract. Serosero RH, Sulistiono, Butet NA, Riani E. 2021. Stock status of coconut crab (Birgus latro) in Daeo, Morotai Island District, North Maluku, Indonesia. Biodiversitas 22: 626-634. The populations of coconut crabs (Birgus latro) in nature continue to decline due to their simple capture for human consumption. This study aimed to determine the status of coconut crab stock in Daeo, Morotai Island Regency, North Maluku, Indonesia including estimations of growth parameters and population size. This research was conducted from October 2016 to September 2017. Growth parameters were estimated based on 12 monthly length-frequency samples. Data analysis was carried out using the ELEFAN I method on the FiSAT II program for estimating growth parameters, and the Schnabel method for estimating population size. The results showed that the level of exploitation of male and female coconut crabs in Daeo was high (E > 0.5). The asymptotic length L∞ for males was 56.96 mm thoracic length (TL) and that of females 52.50 mm TL. The growth coefficient K for males was 0.14 and that for females 0.16. Length to is -1.026 (male) and -0.913 (female). The results generated using the Schnabel method suggested that the population size of the coconut crab in Daeo was 7,466 to 73,948 individuals considering a confidence interval of 95%. The recapture of tagged coconut crabs was merely 0. 82%.

scholarly journals Studi Struktur dan Pertumbuhan Populasi Kerang Pokea (Batissa violacea var. celebensis, von Martens 1897) di Sungai Pohara Sulawesi Tenggara

2018 ◽  
Vol 15 (2) ◽  
Author(s):  
Bahtiar, Hamzah, M Dan Hari, H
Keyword(s):  
Water Quality ◽  
Population Structure ◽  
Von Bertalanffy ◽  
Length Frequency ◽  
Structure Population ◽  
Activity Increase ◽  
Growth Coefficient ◽  
Male And Female ◽  
Growth Structure ◽  
Size Groups

ABSTRAKPokea merupakan bivalvia air tawar yang hidup di segmen muara. Bivalvia ini terusmengalami tekanan sejalan dengan peningkatan aktivitas kegiatan penangkapan danmenurunnya kualitas perairan. Penelitian ini bertujuan untuk mengetahui struktur danpertumbuhan populasi kerang pokea di Sungai Pohara Sulawesi Tenggara. Penelitian inidilaksanakan di segmen muara Sungai Pohara selama setahun dari bulan Maret 2007-Februari2008. Parameter populasi (L∞ dan K) dan to masing-masing dianalisis dengan menggunakanpergerakan modus frekuensi panjang dan nilai L0=0.025. Pola pertumbuhan dianalisismenggunakan inverse von Bertalanffy sedangkan struktur populasi dianalisis menggunakandistribusi normal dari plot Bhattacharya yang secara keseluruhan terakomodasi pada programFiSAT II versi 3.0. Hasil penelitian menunjukkan bahwa lebar asimtotik dan koefisienpertumbuhan jantan dan betina masing-masing yaitu 7.16 cm, 0.59 dan 6.92 cm, 0.96. Olehkarenai tu, pertumbuhan pokea betina lebih cepat dibandingkan pokea jantan. Populasikerang pokea tersebar pada berbagai kelompok ukuran yang mewakili ukuran muda, dewasadan tua dengan nilai tengah berada pada 1.49 dan 6.01 yang menyebar pada tiga kelompokukuran. Kelompok ukuran dominan pada jantan betina relatif berbeda yang tersebar padanilai tengah masing-masing 1cm dan 2cm. Secara umum, struktur populasi pokea di SungaiPohara relatif stabil.Kata kunci : pokea, pertumbuhan, struktur, populasi, sungai, PoharaABSTRACTPokea clam was fresh water bivalve that lived on well into estuary segments. Thisbivalve have experienced in under pressure as activity increase in fishing events and decreasein water quality. This research aimed to understand the structure and growth population ofpokea clam in Pohara river on Southeast Sulawesi. This research was conducted in estuarysegment of Pohara river from March 2007 to February 2008. Parameters of population (L∞dan K) and to were analyzed by using movements in modus of length frequency andLo=0.025. Growth pattern was analyzed by using von Bertalanffy inverse, and populationstructure was analyzed by using normal distribution from Bhattacharya plot with fullaccommodation on FiSAT II version 3.0. The results of this research indicated thatasymptotic width and growth coefficient for male and female were 7.16 cm, 0.59 cm, and0.96 cm. Therefore, the growth of female pokea was faster than male. Pokea clam populationspread to several size groups that represented as young, adult, and old with median 1.49 and6.01. The dominant length measurement on male and female was relatively different whichpropagated in median 1 cm and 2 cm. Generally, population structure of pokea clam inPohara river was relatively stable.Keyword: pokea, growth, structure, population, river, Pohara

Status, Distribution, and Conservation of Native Freshwater Fishes of Western North America

2007 ◽  
Keyword(s):  
North America ◽  
Confidence Interval ◽  
Population Size ◽  
Size Structure ◽  
Freshwater Fishes ◽  
Western North America ◽  
Length Frequency ◽  
Frequency Distributions ◽  
Management Actions ◽  
Roundtail Chub

ABSTRACT Roundtail chub <em>Gila robusta</em> were collected during spring and fall 2003 in the lower Salt and Verde rivers to determine population size and size structure. We collected and passive integrated transpondertagged 262 roundtail chub using a combination of experimental gill nets and canoe electrofishing. The majority of roundtail chub were collected in the upper 16 km of the study area. Length-frequency distributions indicate that the population is comprised almost entirely of large adults with minimal recruitment. The estimated population size of roundtail chub in the lower Salt and Verde rivers during 2003 is 1,657 (95% confidence interval = 1,097–2,742), which represents a 74% decrease from 3 years ago. Based on these results, we conclude that the roundtail chub population in the lower Salt and Verde rivers is declining rapidly due to low recruitment and high natural mortality.We recommend that immediate management actions be taken to ensure the persistence of this population of roundtail chub.

Demographics of the endemic and threatened small cyprinid Pethia setnai from the Northern Western Ghats, India

2020 ◽  
Vol 71 (7) ◽  
pp. 810
Author(s):  
M. SriHari ◽  
Y. Gladston ◽  
S. M. Ajina ◽  
G. B. Sreekanth ◽  
Rajeev Raghavan ◽  
...  
Keyword(s):  
Western Ghats ◽  
Growth Parameters ◽  
Local Population ◽  
Natural Mortality ◽  
Von Bertalanffy ◽  
Fishing Mortality ◽  
Length Frequency ◽  
Growth Coefficient ◽  
First Time ◽  
The Western Ghats

The indigo barb Pethia setnai is a threatened small cyprinid endemic to the Western Ghats biodiversity hotspot of India. In this study, the length–weight relationship and length–frequency-based population dynamics of this species, which are important prerequisites for effective fisheries management, were investigated for the first time based on specimens collected from the Mhadei River in the northern part of the Western Ghats. Estimated von Bertalanffy growth parameters were as follows: theoretical maximum length, L∞, 70.88 mm; growth coefficient, k, 1.50 year–1; and theoretical age at length 0, t0, –0.016 years. Natural mortality of P. setnai was higher than fishing mortality, and the present exploitation level (0.37) was less than 60% of the predicted maximum exploitation, suggesting that the species is not exploited to a level that is detrimental to the local population.

scholarly journals Population dynamics of Chrysichthys nigrodigitatus (Lacépède, 1803) in Ikere-gorge, Oyo State, Nigeria

2021 ◽  
Vol 56 (1) ◽  
pp. 79-86
Author(s):  
S.O. Ajagbe ◽  
D.O. Odulate ◽  
R.O. Ajagbe ◽  
O.S. Ariwoola ◽  
F.I. Abdulazeez ◽  
...  
Keyword(s):  
Assessment Tool ◽  
Growth Parameters ◽  
Stock Assessment ◽  
Total Mortality ◽  
Fishing Mortality ◽  
Length Frequency ◽  
Optimum Length ◽  
Growth Coefficient ◽  
Exploitation Rate ◽  
Length Frequency Data

The growth and mortality parameters of Chrysichthys nigrodigitatus were estimated to assess the sustainability of its exploitation in Ikere-gorge, Oyo State, Nigeria. A total of 1210 of Chrys­ichthys nigrodigitatus were sampled from fishermen catches between January, 2017 and Decem­ber, 2018. C. nigrodigitatus were exploited with gillnet, cast net and traps (Malian trap net and bamboo). Total lengths were measured with fish measuring board. The FAO-ICLARM Stock Assessment Tool (FiSAT II) software was used to analyze length-frequency data of the fish. The estimated growth parameters are: asymptotic length is 60.9 cm, growth coefficient is 0.96, optimum length is 38.51 cm; length at maturity is 33.44 cm while length-at-first-capture is 12.62 cm. The estimated mortality parameters are: total mortality is 3.29 per year, natural mortality is 1.43 per year and fishing mortality is 1.86. It was observed that C. nigrodigitatus of Ikere-gorge were more vulnerable to exploitation at sizes less than their length at maturity. Likewise, the ex­ploitation rate (E = 0.57 yr-1) is greater than sustainable exploitation rate (Emax = 0.46 yr-1). This shows that exploitation of C. nigrodigitatus in Ikere-gorge is not sustainable. Therefore, there is need to reduce fishing pressure on C. nigrodigitatus to ensure its sustainability in Ikere-gorge.

scholarly journals Stock Assessment of Exploited Sardine Populations from Northeastern Bay of Bengal Water, Bangladesh Using the Length-Based Bayesian Biomass (LBB) Method

2021 ◽  
Vol 9 (10) ◽  
pp. 1137
Author(s):  
Partho Protim Barman ◽  
Qun Liu ◽  
Md. Abdullah Al-Mamun ◽  
Petra Schneider ◽  
Mohammad Mojibul Hoque Mozumder
Keyword(s):  
Bay Of Bengal ◽  
Stock Assessment ◽  
Mesh Size ◽  
Length Frequency ◽  
Optimum Length ◽  
Stock Status ◽  
Fisheries Resources ◽  
Fishing Gears ◽  
The Status

Stock assessment is necessary to understand the status of fishery stocks. However, for the data-poor fishery, it is very challenging to assess the stock status. The length-based Bayesian biomass (LBB) technique is one of the most powerful methods to assess the data-poor fisheries resources that need simple length frequency (LF) data. Addressing the present gap, this study aimed to assess the stock status of three sardines (Sardinella fimbriata, Dussumieria acuta, and D. elopsoides) in the Bay of Bengal (BoB), Bangladesh using the LBB method. The estimated relative biomass for S. fimbriata was B/B0 < BMSY/B0, indicating the overfished biomass, while the assessed B/B0 > BMSY/B0 for D. acuta and D. elopsoides indicates healthy biomass. Additionally, for S. fimbriata, the length at first landing was smaller than the optimum length at first landing (Lc < Lc_opt), indicating an overfishing status, but a safe fishing status was assessed for D. acuta and D. elopsoides (Lc > Lc_opt). Therefore, increasing the mesh size of fishing gears may help to ensure the long-term viability of sardine populations in the BoB, Bangladesh.

scholarly journals Population Dynamics of Mud Crab (Scylla serrata) in the Southeastern Coastal Region of Bangladesh

2006 ◽  
Vol 19 (1) ◽  
Author(s):  
M. ZAFAR ◽  
S.M. NURUL AMIN ◽  
M.M. RAHMAN
Keyword(s):  
Growth Parameters ◽  
Coastal Region ◽  
Scylla Serrata ◽  
Frequency Data ◽  
Population Parameters ◽  
Mud Crab ◽  
Length Frequency ◽  
Southeastern Part ◽  
Male And Female ◽  
Length Frequency Data

Population parameters of male and female Scylla serrata were estimated using FiSAT software with length-frequency data collected from different areas of Cox’s Bazar, southeastern part of Bangladesh (Chakaria Sundarban, Moheshkhali and Kutubdia channel) to evaluate the growth parameters, mortality rates and exploitation levels. Asymptotic length (L∝) was 105.9 mm and 105 mm, and growth co-efficient (K) was 0.28/yr and 0.36/yr for male and female S. serrata, respectively. The natural mortalities of S. serrata were 0.49/yr and 0.58/yr and fishing mortalities were 0.35/yr and 0.38/yr for male and female accordingly. Recruitment of this species into the fishery takes place throughout the year. The exploitation level for S. serrata was found to be 0.41 for the male and 0.39 for the female. This study showed that the stocks of male and female S. serrata were not under fishing pressure (E< 0.50) in the Southeastern part of Bangladesh.

scholarly journals The wildcat Felis silvestris in northern Turkey: assessment of status using camera trapping

Oryx ◽  
2011 ◽  
Vol 45 (1) ◽  
pp. 112-118 ◽  
Author(s):  
Özgün Emre Can ◽  
İrfan Kandemi̇r ◽  
İnci̇ Togan
Keyword(s):  
Population Size ◽  
Camera Traps ◽  
Sampling Effort ◽  
Felis Silvestris ◽  
Forest Patch ◽  
Western Turkey ◽  
Lack Of Information ◽  
The Status ◽  
Capture Recapture ◽  
Estimate Population Size

AbstractThe wildcat Felis silvestris is a protected species in Turkey but the lack of information on its status is an obstacle to conservation initiatives. To assess the status of the species we interviewed local forestry and wildlife personnel and conducted field surveys in selected sites in northern, eastern and western Turkey during 2000–2007. In January–May 2006 we surveyed for the wildcat using 16 passive infrared-trigged camera traps in Yaylacı k Research Forest, a 50-km2 forest patch in Yenice Forest in northern Turkey. A total sampling effort of 1,200 camera trap days over 40 km2 yielded photo-captures of eight individual wildcats over five sampling occasions. Using the software MARK to estimate population size the closed capture–recapture model M0, which assumes a constant capture probability among all occasions and individuals, best fitted the capture history data. The wildcat population size in Yaylacı k Research Forest was estimated to be 11 (confidence interval 9–23). Yenice Forest is probably one of the most important areas for the long-term conservation of the wildcat as it is the largest intact forest habitat in Turkey with little human presence, and without human settlements, and with a high diversity of prey species. However, it has been a major logging area and is not protected. The future of Yenice Forest and its wildcat population could be secured by granting this region a protection status and enforcing environmental legislation.

scholarly journals The status of Japanese fisheries relative to fisheries around the world

2017 ◽  
Vol 74 (5) ◽  
pp. 1277-1287 ◽  
Author(s):  
Momoko Ichinokawa ◽  
Hiroshi Okamura ◽  
Hiroyuki Kurota
Keyword(s):  
Maximum Sustainable Yield ◽  
Production Model ◽  
Structured Population Model ◽  
Total Allowable Catch ◽  
Quick Recovery ◽  
Stock Status ◽  
Surplus Production Model ◽  
The Status ◽  
Stock Recruitment ◽  
Age Structured

We present the first quantitative review of the stock status relative to the stock biomass (B) and the exploitation rate (U) that achieved the maximum sustainable yield (MSY) (BMSY and UMSY, respectively) for 37 Japanese stocks contributing 61% of the total marine capture production in Japan. BMSY and UMSY were estimated by assuming three types of stock-recruitment (S-R) relationships and an age-structured population model or by applying a surplus production model. The estimated stock status shows that approximately half of the stocks were overfishing (U/UMSY &gt; 1), and approximately half of the stocks were overfished (B/BMSY &lt; 0.5) during 2011–2013. Over the past 15 years, U decreased and B slightly increased on average. The rate of decrease in the U of the stocks managed by the total allowable catch (TAC) was significantly greater than that of the other stocks, providing evidence of the effectiveness of TAC management in Japan. The above statuses and trends were insensitive to the assumption of the S-R relationship. The characteristics of Japanese stocks composed mainly of resources with relatively high natural mortality, i.e. productivity, suggest that Japanese fisheries have great potential of exhibiting a quick recovery and increasing their yield by adjusting the fishing intensity to an appropriate level.

scholarly journals Occurrence of Dipetalonema gracile in a wild population of woolly monkey Lagothrix poeppiigii in the northeastern Peruvian Amazon

2018 ◽  
Vol 27 (2) ◽  
pp. 154-160
Author(s):  
David Fernandez Conga ◽  
Pedro Mayor ◽  
Adriano Penha Furtado ◽  
Elane Guerreiro Giese ◽  
Jeannie Nascimento dos Santos
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Wild Population ◽  
Human Consumption ◽  
Peruvian Amazon ◽  
New Host ◽  
Woolly Monkey ◽  
Male And Female ◽  
Thoracic And Abdominal ◽  
Scanning Electron

Abstract Dipetalonema gracile (Rudolphi, 1809) (Filarioidea: Onchocercidae) is one of six species of cavities filarial parasites of Neotropical non-human primates. The present study recorded the occurrence of D. gracile, provides morphological and morphometric data and extends the geographical distribution. Adult filariae were obtained from the thoracic and abdominal cavities of 38 specimens of woolly monkey, which were used for local human consumption, in the northeastern Peruvian Amazon. Male and female filarids were processed and analysed using light and scanning electron microscopy. Details of the cephalic papillae, post-cloacal bands and papillae, vulva, phasmid position and lateral appendages are showed by scanning electron microscopy and is recorded the occurrencce of Lagothrix poeppigii monkey as a new host of this filaria in the Yavari-Mirin river basin, Peruvian Amazon.

scholarly journals Prevalence of hepatitis B and C seropositivity in pregnant women

2014 ◽  
Vol 48 (1) ◽  
pp. 89-96 ◽  
Author(s):  
Carla Natalina da Silva Fernandes ◽  
Michelly de Melo Alves ◽  
Michelly Lorrane de Souza ◽  
Gleyce Alves Machado ◽  
Gleiber Couto ◽  
...  
Keyword(s):  
Data Analysis ◽  
Hepatitis B ◽  
Confidence Interval ◽  
Pregnant Women ◽  
Exploratory Study ◽  
Maternity Hospital ◽  
Hospital Records ◽  
Significance Level

The aim of the study was to identify the prevalence of hepatitis B and C seropositivity in pregnant women attended in a public maternity hospital located in Catalao-GO from 2005 to 2009. Descriptive, exploratory study conducted through patients` hospital records. For data analysis, we used SPSS version 18.0. The confidence interval (CI) was calculated using the Person χ² test, considering a significance level of 5% (p <0.05). The prevalence of HBV was 5.64% and HCV 0.098%, predominantly in young pregnant women aged between 20 and 30 years old, single and in their first pregnancy.

Sign in / Sign up

Export Citation Format

Share Document