Growth and mortality of tor fish (Tor soro valenciennes 1842) in asahan river - Issue 4

Sep 5, 2026

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Study to determine the growth and mortality of Tor soro in the Asahan River. Field sampling ran for four months from December 2016 to March 2017, covering headwaters in North Sumatra Province. Fish were collected using fishing gear including a three-meter length gill net with three mesh sizes (¾, 1.5, 2 inch) and electrofishing, followed by sample measurements. Total mortality (Z) reached 4.09 per year, with natural mortality (M) 0.66 and catch-related mortality (F) 3.43, giving an exploitation rate of 0.84, exceeding the optimum value of 0.5.

LanguageEnglish

CategoryGeneral

FormatPDF

Pages4

Reading Time2 min

AccessFree to download

Introduction

Tor fish background and distribution

Research motivation in Asahan River

Methods

Sampling design and duration

Growth and mortality estimation approaches

Results and discussion

Length-weight relationship

Growth pattern and parameter interpretation

International Journal of Fisheries and Aquatic Research ISSN: 2456-7248, Impact Factor: RJIF 5.44 [www.fishjournals.com](www.fishjournals.com) Volume 2; Issue 4; July 2017; Page No. 23-26 Growth and mortality of tor fish (Tor soro valenciennes 1842) in asahan river Rumondang, Azizah Mahari Department of Aquaculture, University of Asahan, Indonesia Abstract This study aims to determine the growth and mortality oftor fish in the River Asahan. The study was conducted for 4 months from December 2016 to March 2017 in the Asahan River which still includes headwaters areas; Administratively into the territory of North Sumatra Province. Fish sampling using fishing gear in the form of a length of three meters, gill net with three mesh (¾ , 1.5 and 2 inch) with length of 20 m and width of 2 meters, and electrofishing. The study included field activities (sampling of fish) followed by sample measurements. Total mortality rate (Z) of Tor fish 4.09 per year with natural mortality rate (M) 0.66; The mortality rate due to catch (F) 3.43, so that the rate of exploitation is 0.84. The rate of exploitation of the Tor fish in the Asahan River exceeds the optimum exploitation rate value of 0.5. Keywords: growth, mortality, torfish, asahan river Introduction Tor fish is included in the family Cyprinidae. Kottelat et al.(1993), said there are four species of the Tor genus in Indonesia. Fishbase (2008), noted the four species, among them Mahseer (Tor soro Valenciennes 1842) with local name is Tor soro, and kancra bodas, Mahsir Javsky (T. tambra Valenciennes 1842) with local name is Sibaro, Semah Mahseer (T. douronensis Valenciennes 1842) with the local name is Kancera, Thai Mahseer (T. tambroides Bleeker 1854) with the local name is Sengkareng and Garing. This study focused on Tor soro fish as a research study. Characteristics of Tor soro fish than other Tor genus can be known visually. Haryono and Tjakrawidjaja (2005) , distinguish through the existence of two lobes in the lower lip of the fish's mouth. Other differentiators are known based on the size of the lower anal fin rather than the dorsal fin and there is a shiny silver color on the back. The spread of Tor fish in Indonesia can be found in Sumatra, Kalimantan, and Java (Haryono 2006) . Tor fish can be found in rivers or public waters with rock subtrates. This is because the Tor fish can grow well in water conditions with the type of rocky substrate, clear, high oxygen needs, and flow from medium to fast (Nontji 1992; Conway and Kottelat 2011; Wibowo 2012) . The existence of Tor fish can also be found in Ciliwung River Bogor and ponds in Kuningan, West Java. The existence of Tor fish in nature is increasingly threatened, including high utilization intensity, unsustainable fishing, anthropogenic activities, and land conversion (Ali et al., 2013) . Threats received by Tor fish in Ciliwung river are ecologically damaged such as critical land, high fluctuation of debit, deforestation, and land reclamation (Utomo and Krismono 2006; Sikder et al. 2012; KLH 2014) . The potential of Tor fish resources in the Asahan River is not widely known. One type of Tor fish found in the river Asahan and is an important economic consumption fish is the Tor soro fish. Based on interviews with some fishermen, there is an indication of Tor fish population decreasing. This is indicated by the decreasing of catch. Meanwhile, information on the biological and ecological aspects of Tor fish still limited even more to the population found in the headwaters area of the Asahan River. In order to formulate the appropriate management strategy of Tor fish resources for sustainable use, it is necessary to have enough basic data including biological and ecological aspects in their natural habitat. One of the important data that needs to be known as input for fishery regulation and management of resource potency is population dynamics aspect, including catching rate parameter and mortality parameter (Gul

FAQs

What was the main objective of the study?

The study aimed to determine the growth and mortality of Tor soro fish in the Asahan River.

How long was the field study conducted and when?

Sampling was conducted for four months, from December 2016 to March 2017.

What mortality and exploitation rates were reported?

Total mortality (Z) was 4.09 per year, natural mortality (M) 0.66, catch mortality (F) 3.43, and the exploitation rate was 0.84, which exceeded the optimum exploitation rate of 0.5.

Sep 5, 2026

Upload by Eliana