Corresponding author: Md. Yeamin Hossain ( hossainyeamin@gmail.com ) Academic editor: Rodolfo Reyes
© 2021 Md. Rabiul Hasan, Md. Yeamin Hossain, Zannatul Mawa, Sumaya Tanjin, Md. Ashekur Rahman, Uttam Kumar Sarkar, Jun Ohtomi.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Hasan MdR, Hossain MdY, Mawa Z, Tanjin S, Rahman MdA, Sarkar UK, Ohtomi J (2021) Evaluating the size at sexual maturity for 20 fish species (Actinopterygii) in wetland (Gajner Beel) ecosystem, north-western Bangladesh through multi-model approach: A key for sound management. Acta Ichthyologica et Piscatoria 51(1): 29-36. https://doi.org/10.3897/aiep.51.63339
|
Effective fisheries management depend on having an exact assessment of biological parameters, including growth parameters, reproduction, size at sexual maturity (Lm), and stock assessment. The purpose of this research was to estimate the size at sexual maturity (Lm) for 20 fish species belongs to 14 families from a wetland (Gajner Beel) ecosystem in the north-western (NW) Bangladesh through multi-models such as length (Lmax) based empirical model, gonadosomatic index (GSI)-based model, and logistic model using commercial catches from January to December 2018. Also, we assessed the Lm in other water-bodies worldwide. Specimens’ total length (TL) was noted up to 0.1 cm using measuring board body weight (BW) and gonad weight (GW) weighed by digital electronic balance with 0.01 g accuracy. To assess the Lm, maximum body length (Lmax) based empirical model; the relation between TL (total length in cm) vs. GSI (gonadosomatic index in %); and a logistic model were considered. The minimum Lm was 4.64, 3.90, and 4.15 cm for Chanda nama Hamilton, 1822 and the maximum was 25.33, 24.50, and 24.70 cm for Channa striata (Bloch, 1793) through Lmax, GSI, and logistic-based models, respectively. From these three models, the minimum mean Lm was 4.23 cm for C. nama and the maximum was 24.84 cm for C. striata. The Lm with 50.0% species was in 8.80 cm TL. We also calculated the Lm from different bodies of water based on Lmax. This study was generated data of 17 new Lm among 20 species, which are globally absent. Therefore, the study will help develop sustainable management strategies, conservation through the implementation of mesh size based on the size at sexual maturity (Lm).
Bangladesh, logistic models, fish species, size at first sexual maturity, Gajner Beel
In Bangladesh, fishes are the most affluent organisms, which secure livelihood, contribute food, generate employment, and are used to develop the nation’s economy (
Bangladesh is fortunate to have vast aquatic resources and rich fish genetic diversity. It has a lot of inland water bodies that host 267 freshwater fish species. Biodiversity of fishes is very essential for nutrition and livelihoods for the rural people in Bangladesh (
A land, which is inundated by water, annually or seasonally, permanently or temporarily that is called a wetland (
Types | Wetland | Area [km2] |
Open waters | Rivers | 7497 |
Estuaries and mangrove swamps | 6102 | |
Beels and haors | 1142 | |
Inundable floodplains | 54 866 | |
Kaptai Lake | 688 | |
Closed water | Ponds | 1469 |
Baors (Oxbow Lakes) | 55 | |
Brackish-water farms | 1080 | |
Total | 72 899 |
Gajner Beel is situated at Sujanagar, Pabna in north-western (NW) Bangladesh. This Beel is used as an imperative feeding and spawning ground by many freshwater fish species. Near about 0.5 million people of surrounding villages of this Beel are directly or indirectly reliant on this wetland for their livelihood (
Effective fisheries management depends on having an exact assessment of biological parameters, including growth parameters, reproduction, size at sexual maturity (Lm), and stock assessment (
Scanning of the literature shows non-availability of species-specific data on size at sexual maturity (Lm) of these 20 species except Channa striata (Bloch, 1793) (see
The presently reported study was conducted in Gajner Beel (23°55′N, 89°33′E), which is located at Sujanagar, Pabna, NW Bangladesh (Fig.
GSI (%) = GW/BW*100
where, GW referred to the gonad weight (g) and BW were body weight (g). The length of 50% maturity (50% Lm) of the 20 fish species was estimated using three models, which were shown in Table
Size at sexual maturity of 20 fish species was calculated by these three models.
Model name | Equations | Reference |
Empirical model | log (Lm) = –0.1189 + 0.9157* log (Lmax) |
|
GSI based model | L m = TL vs. GSI |
|
Logistic model | PMI = 100/[1 + exp{–f (TLm–TL50)}] |
|
Altogether 3040 specimens of 20 fish species were considered in the presently reported study and a list of fish species is given in Table
List of total 20 fish species in a wetland ecosystem (Gajner Beel), NW Bangladesh.
Sl. No | Family | Scientific name | Common name |
01 | Ambassidae | Chanda nama | Chanda |
02 | Anabantidae | Anabas testudineus | Koi |
03 | Bagridae | Mystus cavasius | Gulsa |
04 | Mystus tengara | Tengra | |
05 | Belonidae | Xenentodon cancila | Kakila |
06 | Channidae | Channa orientalis | Cheng |
07 | Channa punctata | Taki | |
08 | Channa striata | Shol | |
09 | Clupeidae | Gudusia chapra | Chapila |
10 | Cobitidae | Lepidocephalichthys guntea | Gutum |
11 | Cyprinidae | Amblypharyngodon mola | Moa |
12 | Puntius sophore | Jat punti | |
13 | Salmostoma bacaila | Chela | |
14 | Gobiidae | Glossogobius giuris | Bele |
15 | Heteropneustidae | Heteropneustes fossilis | Shingi |
16 | Mastacembelidae | Macrognathus aculeatus | Shal baim |
17 | Macrognathus pancalus | Guchi | |
18 | Nandidae | Nandus nandus | Bheda |
19 | Osphronemidae | Trichogaster fasciata | Kholisa |
20 | Siluridae | Ompok pabo | Pabda |
Size at first sexual maturity (Lm) of 20 fish species in a wetland ecosystem (Gajner Beel), NW Bangladesh.
Scientific name | n | Minimum length [cm] | Maximum length [cm] | Size at sexual maturity (Lm) | |||
---|---|---|---|---|---|---|---|
Maximum length based | GSI based | Logistic-based models | Mean | ||||
Chanda nama | 196 | 2.40 | 7.20 | 4.64 (3.81–5.68) | 3.90 | 4.15 | 4.23 |
Anabas testudineus | 130 | 7.50 | 16.40 | 9.85 (7.84–12.39) | 10.20 | 9.10 | 9.72 |
Mystus cavasius | 124 | 5.30 | 16.90 | 10.13 (8.05–12.75) | 9.80 | 9.70 | 9.88 |
Mystus tengara | 139 | 4.80 | 12.60 | 7.74 (6.23–9.65) | 7.00 | 7.10 | 7.28 |
Xenentodon cancila | 118 | 8.50 | 24.00 | 13.96 (10.95–17.77) | 12.98 | 13.45 | 13.46 |
Channa orientalis | 152 | 8.10 | 19.00 | 11.27 (8.92–14.24) | 12.48 | 11.00 | 11.58 |
Channa punctata | 178 | 5.30 | 19.40 | 11.49 (9.09–14.53) | 12.20 | 11.25 | 11.65 |
Channa striata | 128 | 9.50 | 46.00 | 25.33 (19.35–32.89) | 24.50 | 24.70 | 24.84 |
Gudusia chapra | 126 | 4.40 | 14.60 | 7.18 (5.79–8.93) | 6.90 | 6.95 | 7.00 |
Lepidocephalichthys guntea | 117 | 5.00 | 10.30 | 6.44 (5.22–7.98) | 6.50 | 6.20 | 6.38 |
Amblypharyngodon mola | 193 | 3.90 | 7.80 | 4.99 (4.09–6.13) | 4.90 | 4.85 | 4.91 |
Puntius sophore | 191 | 4.20 | 11.00 | 6.83 (5.53–8.49) | 7.00 | 6.50 | 6.78 |
Salmostoma bacaila | 114 | 4.20 | 10.00 | 6.26 (5.09–7.76) | 6.50 | 5.90 | 6.22 |
Glossogobius giuris | 189 | 3.90 | 14.70 | 8.91(7.13–11.17) | 8.10 | 8.45 | 8.49 |
Heteropneustes fossilis | 180 | 6.30 | 24.10 | 14.02 (10.99–17.84) | 12.20 | 13.96 | 13.39 |
Macrognathus aculeatus | 115 | 8.70 | 27.00 | 15.55 (12.14–19.86) | 16.18 | 15.00 | 15.58 |
Macrognathus pancalus | 190 | 6.90 | 15.70 | 9.47 (7.55–11.89) | 9.80 | 9.00 | 9.42 |
Nandus nandus | 168 | 6.50 | 17.20 | 10.29 (8.18–12.96) | 10.40 | 9.95 | 10.21 |
Trichogaster fasciata | 170 | 3.30 | 9.30 | 5.86 (4.77–7.24) | 6.00 | 5.00 | 5.62 |
Ompok pabo | 122 | 4.80 | 17.80 | 10.62 (8.43–13.39) | 9.85 | 10.20 | 10.22 |
Calculate the size at sexual maturity based on maximum length from the different water bodies in world wide.
Species name | Sex | Habitat | L max [cm] | L m (95% CL) |
---|---|---|---|---|
Chanda nama | C | Brahmaputra River tributary, Bangladesh | 6.40 | 4.16 (3.44–5.08) |
C | Deepor beel, Assam, India | 7.00 | 4.52 (3.72–5.53) | |
C | Hirakud Reservoir, India | 10.10 | 6.32 (5.13–7.83) | |
C | Brahmaputra River, Bangladesh | 7.40 | 4.75 (3.91–5.83) | |
C | Ganges River, Rajshahi, Bangladesh | 7.20 | 4.64 (3.81–5.68) | |
C | 11.00 | 6.83 (5.53–8.49) | ||
Anabas testudineus | C | Chi River, Thailand | 16.50 | 9.91 (7.89–12.46) |
C | Pampanga River, Candaba, Philippines | 11.70 (SL) | 7.23 (5.84–9.00) | |
C | Agusan Marsh, Philippines | 17.00 | 10.18 (8.09–12.82) | |
C | Tetulia River, Bangladseh | 16.10 | 9.69 (7.72–12.18) | |
C | India | 25.00 | 14.49 (11.35–18.47) | |
Mystus cavasius | C | Betwa River, India | 27.40 | 15.76 (12.30–20.14) |
C | Ganges River, Bangladesh | 15.00 | 9.08 (7.25–11.39) | |
C | Brahmaputra River tributary, Bangladesh | 11.30 | 7.00 (5.66–7.71) | |
C | Qadirabad barrage, Chenab River, Pakistan | 17.80 | 10.62 (8.43–13.39) | |
C | 40.0 | 22.29 (17.12–28.81) | ||
Mystus tengara | C | Brahmaputra River, Bangladesh | 11.20 | 6.95 (5.62–8.64) |
C | Ganges River, Bangladesh | 11.60 | 7.18 (5.79–8.93) | |
C | India | 18.00 | 10.73 (8.51–13.53) | |
Xenentodon cancila | C | Atrai River, Bangladesh | 18.10 | 10.78 (8.55–13.60) |
C | Hirakud reservoir, India | 18.60 | 11.06 (8.76–13.96) | |
C | Chi River, Thailand | 23.00 | 13.43 (10.55–17.07) | |
C | India | 40.00 | 22.29 (17.12–28.81) | |
Channa orientalis | C | Basantar River, India | 19.60 | 11.60 (9.17–14.67) |
C | Gajner beel floodplain, Pabna, Bangladesh | 18.40 | 10.95 (8.68–13.82) | |
C | 33.00 | 18.69 (14.47–24.02) | ||
Channa punctata | F | Siruvani River, Tamil Nadu, India | 24.40 | 14.18 (11.11–18.05) |
M | 25.00 | 14.49 (11.35–18.47) | ||
F | Vellar River, Tamil Nadu, India | 24.50 | 14.23 (11.15–18.12) | |
M | 27.90 | 16.03 (12.49–20.49) | ||
F | Cauvery River, Tamil Nadu, India | 25.90 | 14.97 (11.70–19.10) | |
M | 25.40 | 14.71 (11.51–18.75) | ||
F | Tamirabrani River, Tamil Nadu, India | 27.40 | 15.76 (12.30–20.14) | |
M | 26.80 | 15.45 (12.06–19.72) | ||
C | Hirakud Reservior, India | 19.20 | 11.38 (9.01–14.38) | |
C | Mathabhanga River, Bangladesh | 18.90 | 11.22 (8.88–14.17) | |
C | 31.00 | 17.65 (13.70–22.64) | ||
Channa striata | F | North Kerian rice agoecosystem, Malaysia | 54.00 | 29.34 (22.27–38.28) |
M | 45.20 | 24.93 (19.06–32.35) | ||
C | Agusan Marsh, Philippines | 61.0 | 32.80 (24.78–42.96) | |
C | Chi River, Thailand | 51.00 | 277.84 (21.18–36.26) | |
C | Pampanga River, Candaba, Philippines | 41.40 (SL) | 23.0 (17.65–29.77) | |
Channa striata | C | Pearl River, China | 39.30 | 21.93 (16.86–28.34) |
C | 100.00 | 51.58 (38.20–68.60) | ||
Gudusia chapra | F | Lake, Mymensingh, Bangladesh | 13.70 (SL) | 8.36 (6.70–10.45) |
M | 12.60 (SL) | 7.74 (6.23–9.65) | ||
C | Lower Brahmaputra, India | 13.80 | 8.41 (6.74–10.52) | |
C | Betwa River, India | 15.00 | 9.08 (7.25–11.39) | |
C | Hirakud Reservoir, India | 11.60 | 7.18 (5.79–8.93) | |
C | Ganges Lower region, Bangladesh | 13.40 | 8.19 (6.57–10.23) | |
C | 20.00 | 11.82 (9.33–14.95) | ||
Lepidocephalichthys guntea | C | Atrai River, Bangladesh | 8.70 | 5.51 (4.50–6.80) |
C | Ganges Lower region, Bangladesh | 9.60 (SL) | 6.03 (4.91–7.46) | |
C | 15.00 | 9.08 (7.25–11.39) | ||
Amblypharyngodon mola | F | Wetlands of Dishoi and Neamatighat, Assam, India | 9.00 | 5.69 (4.64–7.02) |
M | 6.60 | 4.28 (3.53–5.23) | ||
C | Hirakud Reservoir, India | 7.20 | 4.64 (3.81–5.68) | |
F | Payra River, Bangladesh | 5.80 (SL) | 3.80 (3.16–4.63) | |
M | 5.40 (SL) | 3.56 (2.97–4.33) | ||
C | Atrai River, Bangladesh | 6.20 | 4.04 (3.35–4.93) | |
C | Ganges River, Bangladesh | 8.10 | 5.16 (4.23–6.35) | |
F | Garjan beel, India | 8.30 | 5.28 (4.32–6.50) | |
M | 7.60 | 4.73 (4.00–5.98) | ||
C | Ganges lower region, Bangladesh | 5.9 (SL) | 3.86 (3.20–4.71) | |
C | Mathabhanga River, Bangladesh | 7.00 | 4.52 (3.72–5.53) | |
U | South 24 Parganas, India | 8.70 | 5.51 (4.50–6.80) | |
C | India | 20.00 | 11.82 (9.33–14.95) | |
Puntius sophore | C | Ganga basin tributaries, India | 18.50 | 11.00 (8.72–13.89) |
C | Mathabhanga River, Bangladesh | 10.20 | 6.38 (5.18–7.90) | |
C | Hirakud Reservoir, India | 10.80 | 6.72 (5.44–8.34) | |
C | Brahmaputra River basin, India | 7.40 (SL) | 4.75 (3.91–5.83) | |
C | 20.00 | 11.82 (9.33–14.95) | ||
Salmostoma bacaila | C | Atrai River, Bangladesh | 10.50 | 6.55 (5.31–8.12) |
C | Hirakud Reservoir, India | 14.70 | 8.91 (7.13–11.17) | |
C | 18.00 | 10.73 (8.51–13.53) | ||
Glossogobius giuris | C | Brahmaputra River, Bangladesh | 9.70 | 6.09 (4.95–7.54) |
C | Hirakud Reservoir, India | 22.50 | 13.16 (10.35–16.71) | |
C | Hongshui River, China | 17.50 | 10.46 (8.30–13.18) | |
C | Agusan Marsh, Philippines | 19.50 | 11.54 (9.13–14.60) | |
C | Ganges lower region, Bangladesh | 23.60 | 13.75 (14.79–17.49) | |
F | 22.80 | 13.32 (10.47–16.92) | ||
M | 23.60 | 13.75 (14.79–17.49) | ||
C | 17.90 (SL) | 10.67 (8.47–13.46) | ||
C | Estuaries, South Africa | 11.90 (SL) | 7.34 (5.92–9.15) | |
C | 50.00 (SL) | 27.34 (20.82–35.59) | ||
Heteropneustes fossilis | C | Atrai River, Bangladesh | 13.70 | 8.36 (6.70–10.45) |
C | Gajner beel floodplain, Pabna, Bangladesh | 16.50 | 9.91 (7.89–12.46) | |
C | Ganga River, India | 31.00 | 17.65 (13.70–22.64) | |
C | Gajner beel floodplain, Pabna, Bangladesh | 26.80 | 15.45 (12.06–19.72) | |
C | 24.10 | 14.02 (10.99–17.84) | ||
Macrognathus aculeatus | C | Ganges River, NW Bangladesh | 23.40 | 13.64 (10.71–17.35) |
C | Thailand | 38.00 | 21.27 (16.37–27.45) | |
Macrognathus pancalus | C | Atrai River, Bangladesh | 12.60 | 7.74 (6.23–9.65) |
C | Mathabhanga River, Bangladesh | 16.20 | 9.74 (7.76–12.25) | |
C | Gajner beel floodplain, Pabna, Bangladesh | 14.40 | 8.75 (7.00–10.95) | |
C | Hirakud Reservoir, India | 16.60 | 9.96 (7.93–12.53) | |
C | 18.00 | 10.73 (8.51–13.53) | ||
Nandus nandus | F | Ganges River, NW Bangladesh | 13.60 | 8.30 (6.66–10.38) |
M | 12.60 | 7.74 (6.23–9.65) | ||
C | Brahmaputra River, Bangladesh | 14.00 | 8.52 (6.83–10.67) | |
C | Mathabhanga River, Bangladesh | 14.20 | 8.63 (6.91–10.81) | |
C | Gajner beel floodplain, Pabna, Bangladesh | 14.10 | 8.58 (6.87–10.74) | |
C | 20.00 | 11.82 (9.33–14.95) | ||
Trichogaster fasciata | C | Deepor beel, Assam, India | 8.10 | 5.16 (4.23–6.35) |
C | Gajner beel floodplain, Pabna, Bangladesh | 9.40 | 5.92 (4.82–7.32) | |
C | 12.50 | 7.68 (6.18–9.58) | ||
Ompok pabo | C | 25.00 | 14.49 (11.35–18.47) | |
F | Feni and Gomati River, Tripura, India | 19.00 | 11.27 (8.92–14.24) | |
M | 20.70 | 12.19 (9.62–15.45) | ||
C | Payra River, southern Bangladesh | 22.30 | 13.05 (10.27–16.57) |
This study referred to the first strive to evaluate the size at sexual maturity of 20 fishes through multiple models in the Gajner Beel wetland ecosystem. The selection of permissible capture size at first maturity is broadly used and it is also used as an important tool in fisheries management (
Nevertheless, the Lm was estimated by several models including brooding of eggs over time (especially for crustaceans), the appearance of the ovary and maturation stages over time (
Among the 20 fishes, C. nama was the smallest and C. striata the largest in TL. Information on Lm was available only for three species (Channa striata, Gudusia chapra, and Puntius sophore) in FishBase (
Optimum catchable length (Lopt) of 20 fish species in a wetland ecosystem (Gajner Beel), NW Bangladesh.
Scientific name | n | Minimum length [cm] | Maximum length [cm] | Optimum catchable length of individuals (Lopt) |
---|---|---|---|---|
Chanda nama | 196 | 2.40 | 7.20 | 4.80 |
Anabas testudineus | 130 | 7.50 | 16.40 | 10.93 |
Mystus cavasius | 124 | 5.30 | 16.90 | 11.27 |
Mystus tengara | 139 | 4.80 | 12.60 | 8.40 |
Xenentodon cancila | 118 | 8.50 | 24.00 | 16.00 |
Channa orientalis | 152 | 8.10 | 19.00 | 12.67 |
Channa punctata | 178 | 5.30 | 19.40 | 12.93 |
Channa striata | 128 | 9.50 | 46.00 | 30.67 |
Gudusia chapra | 126 | 4.40 | 14.60 | 9.73 |
Lepidocephalichthys guntea | 117 | 5.00 | 10.30 | 6.87 |
Amblypharyngodon mola | 193 | 3.90 | 7.80 | 5.20 |
Puntius sophore | 191 | 4.20 | 11.00 | 7.33 |
Salmostoma bacaila | 114 | 4.20 | 10.00 | 6.67 |
Glossogobius giuris | 189 | 3.90 | 14.70 | 9.80 |
Heteropneustes fossilis | 180 | 6.30 | 24.10 | 16.07 |
Macrognathus aculeatus | 115 | 8.70 | 27.00 | 18.00 |
Macrognathus pancalus | 190 | 6.90 | 15.70 | 10.47 |
Nandus nandus | 168 | 6.50 | 17.20 | 11.47 |
Trichogaster fasciata | 170 | 3.30 | 9.30 | 6.20 |
Ompok pabo | 122 | 4.80 | 17.80 | 11.87 |
Fish diversity of Gajner Beel wetland ecosystem is declining at a faster rate because of many factors; damage of habitat, aquatic pollution, fishing pressure, natural disaster, extreme floodplain siltation, and reclamation of wetland (
The presently reported study concludes that around 50.0% of species were sexually matured in 8.80 cm TL. So, we strongly suggest that ≤ 8.80 cm TL fishes cannot be recommended for harvesting. As a result, at least 50% of species survive in the wetland ecosystem.
We are very much thankful to the Bangladesh Agriculture Research Council, NATP-2, ID: 484 for the financial support to complete this research.