Depik Jurnal Ilmu-Ilmu Perairan, Pesisir dan Perikanan (2021) 10(2): 167-173 DEPIK Jurnal Ilmu-Ilmu Perairan, Pesisir dan Perikanan Journal homepage: www.jurnal.unsyiah.ac.id/depik * Corresponding author. Email address: chaliluddin@unsyiah.ac.id p-ISSN 2089-7790; e-ISSN 2502-6194 Received 1 June 2021; Received in revised from 14 July 2021; Accepted 5 August 2021 Available online 26 August 2021 This is an open access article under the CC - BY 4.0 license (https://creativecommons.org/licenses/by/4.0/) Fishing season of large pelagic fish in Idi Rayeuk waters, East Aceh, Indonesia Makwiyah A. Chaliluddin 1,2,* , Rizka Alfita 2 , Thaib Rizwan 2 , Rahmat Rizqi 2 , Rosi Rahayu 2 , Sayyid Afdhal El Rahimi 3 , Ichsan Rusydi 3 1 Fishing Technology Laboratory, Faculty of Marine and Fisheries, Universitas Syiah Kuala, Banda Aceh, Indonesia. 2 Department of Fisheries Resource Utilization, Faculty of Marine and Fisheries, Universitas Syiah Kuala, Banda Aceh, Indonesia. 3 Department of Marine Sciences, Faculty of Marine and Fisheries, Universitas Syiah Kuala, Banda Aceh, Indonesia. ARTICLE INFO ABSTRACT Keywords: Fishing season Large pelagic Purse seine Idi Rayeuk Aceh DOI: 10.13170/depik.10.2.21203 Large pelagic fish live on the water surface in groups. Skipjack tuna (Katsuwonus pelamis), yellowfin tuna (Thunnus albacares), mackerel tuna (Euthynnus affinis), mackerel (Scomberomous guttatus) are species of fishes that mainly catches by fishermen using purse seines. This study aims to determine the length and weight of large pelagic fish in the water of Idi Rayeuk and best the fishing season. This research was conducted in one month. Fish samples were collected from fishermen that used purse seine and landed their catches at the Idi Rayeuk Fishing Port, East Aceh. Additionally, the data was derived from the fishing port time-series during 2015 to 2019. The result showed that the yellowfin tuna (Thunnus albacares) has a length between 37 - 58 cm with a weight of 1.0 - 3.2 kg, skipjack tuna (Katsuwonus pelamis) 32 - 58 cm in length and weight 0.5 - 3.0 kg, mackerel tuna has 33 - 54 cm of length with a weight of 0.6 - 2.5 kg, and mackerel has 44 - 66 cm of length and weighing 0.7 - 1.7 kg. Its also found that the peak season for catching yellowfin tuna (Thunnus albacares) and mackerel tuna is May and June, and the lowest season in December for the yellowfin tuna, and December and January for the mackerel tuna. The peak season for skipjack fishing occurs in May, August, and October, and the low season occurs in November and December. Meanwhile, the peak season for fishing mackerel occurs in May, September, and October, while the low season occurs in January, February, and March. Introduction A purse seine is a type of fishing gear that is more effective for catching pelagic fish around the water surface. The purse seine is made from a long net where the length of the bottom net is equal to or longer than the top. The net construction shape varies between areas, such as the shape of a rectangle, trapezoid, and a net bag located at the middle of the net (webbing) and some located at the edge of the net. The characteristic of the purse seine lies at the bottom ring of the net (Chaliluddin et al., 2018; Chaliluddin et al., 2019a). Large pelagic fish is one of the fisheries commodities with a very high economic value compared to other fish species (Nelwan et al., 2015). The fishing gear often used to catch large pelagic fish is purse seine, longline, pole and line, trolling line (Zainuddin et al., 2017). A purse seine is a fishing gear commonly used by small-scale to large-scale fishers/industry to catch small and large pelagic fish species (Chaliluddin et al., 2019b). Catching these fishes in the right season increases productivity and implements sustainable fisheries by preventing overfishing (Agustina et al., 2016). In fisheries biology, the fish length-weight relationship is essential for fisheries resource management, for example, in determining the fishing gear selectivity to catch only the suitable size (Aprilla et al., 2021; Chaliluddin et al., 2021). Furthermore, Afdhila et al. (2019); Agista et al. (2019) stated that the measurement of fish length and weight aims to determine the variation in weight and a certain length of fish individually or in groups as an indication of obesity, health, productivity and physiological conditions including gonad development. Analysis of