Ichthyofauna of Merbau River, Leuser Ecosystem Area, Indonesia: species composition, diversity, biometric condition, potency, and conservation status

Figures & data

Figure 1. Location of the study sites (sampling locations with green dot, Merbau River indicated with red line).

Figure 2. Sampled localities in the Merbau River, LEA. (A) Lubuk Ombo, (B) Kampung Selamat, (C) Kampung Tenggulun, (D) Alur Bujok, (E) Tenda Biru, (F) Tualang Tukul. Photographs by Siti Maulizar.

Table I. Description of research stations.

Station	Location	Coordinate	Description
1	Lubuk Ombo	N 04°02'03,22'' E 97°95'23,21''	The width of the river reaches ten meters with a depth of around four meters, the current was relatively fast. The substrate consists of small and sandy rocks. The brightness was high with greenish watercolor, the pH ranges from 8.2 to 8.8, and the DO ranges from 6.9 to 7.4 Mg/L, water temperature ranges from 24°C–26°C. The vegetation cover around the site was dominated by Meranti (Shorea sp.) and Teak (Tectona grandis) species.
2	Kampung Selamat	N 04°01'36,948'' E 97°57'17,22''	The river’s width reaches five meters with a depth of around five meters. The current was relatively fast. The substrate consists of small and sandy rocks. Low turbidity with turquoise watercolor. pH ranges from 8.5 to 8.1, and DO ranges from 6.5 to 7.2 Mg/L. Vegetation cover around the watershed includes meranti (Shorea sp.) and palm (Elaeis guineensis). Water temperature ranged from 25°C–27°C.
3	Kampung Tenggulun	N 04°02'05,36'' E 097°57'34,86''	The river’s width reaches eight meters with a depth of more than five meters. The current was relatively slow. The substrate consisted of gravel sand. Low brightness with brownish-green watercolor. pH ranged from 6.1 to 6.6, and DO ranged from 6.2 to 7.6 Mg/L. Water temperature ranged from 24–26°C. Vegetation around the river was ferns (Nephrolepis cordifolia) and palm (Elaeis guineensis)
4	Alur Bujuk	N 04°01'22,77'' E 097°58'14,86''	The river’s width reaches two meters with a depth of one point five meters. The current was relatively slow. The substrate was dominated by mud. The brightness was low with brownish-yellow watercolor. pH ranged from 5.8 to 6.4, and the DO ranged from 5.2 to 6.2 Mg/L. Water temperature ranged from 24–28°C. Vegetation around the river was dominated by grass (Cyperus rotundus) and shrubs (Cenchrus purpureus).
5	Tenda Biru	N 04°02'05,70'' E 097°57'54.92''	The river’s width reaches six meters with a depth of more than five meters. The current was relatively slow. The substrate was dominated by mud and sand. Watercolor was greenish. pH ranged from 8.4 to 9.1, and the DO ranged from 5.7 to 6.7 Mg/L. The temperature of the water ranged from 26°C–28°C. Vegetation around the river was dominated by shrubs (Cenchrus purpureus and Tridax procumbens), and palms (Elaeis guineensis).
6	Tualang Tukul	N 04°06'26,93'' E 97°98'73,68''	The river’s width reached eight meters with a depth of one point five meters. The current was relatively slow. The substrate was dominated by mud. The watercolor was brownish-yellow. pH ranged from 5.5 to 6.2, and the DO ranged from 5.4 to 6.1 Mg/L. The temperature of the water ranged from 26°C–28°C. Vegetation around the river was grass (Cyperus rotundus), shrubs (Cenchrus purpureus), and palms (Elaeis guineensis).

Table II. Taxonomic classification, local name, distribution pattern, conservation status and potency of fishes in Merbau River, LEA, Indonesia.

ORDER Family Species	Local Name	LO	KS	KT	AB	TB	TT	Total	IUCN	Potency	Voucher
CYPRINIFORMES
Cyprinidae
Crossocheilus cobitis (Bleeker, 1854)	Lemungkus	18	9	0	0	0	0	27	LC	C	ARY16110
Cyclocheilichthys apogon (Valenciennes, 1842)	Mata merah	3	0	0	20	2	5	30	LC	C	ARY16104
Hampala macrolepidota (Kuhl & van Hasselt, 1823)	Sebarau	0	4	0	2	3	4	13	LC	C	ARY16108
Labiobarbus leptocheilus (Valenciennes, 1842)	Sepui	0	0	5	9	3	0	17	LC	C	ARY16102
Mystacoleucus obtusirostris (Valenciennes, 1842)	Kempras	0	4	3	11	3	0	21	LC	C	ARY16106
Osteochilus vittatus (Valenciennes, 1842)	Paitan	0	4	15	32	10	9	70	LC	C	ARY16103
Oxygaster anomalura (van Hasselt, 1823)	Awur-awur	0	0	0	17	4	0	21	LC	C	ARY16109
Rasbora sumatrana (Bleeker, 1952)	Seluang	4	5	7	14	6	0	36	DD	C&O	ARY16105
Striuntius lateristriga (Valenciennes, 1842)	Gempual	0	2	8	11	8	0	29	LC	C&O	ARY16107
ANABANTIFORMES
Channidae
Channa lucius (Cuvier, 1831)	Gabus bujok	0	0	0	7	1	1	9	LC	C	ARY16112
Channa striata (Bloch, 1793)	Gabus sawah	0	0	0	6	2	2	10	LC	C	ARY16111
Pristolepididae
Pristolepis fasciata (Bleeker, 1851)	Keper	0	0	0	13	5	4	22	LC	C&O	ARY16113
SILURIFORMES
Clariidae
Clarias batrachus (Linnaeus, 1758)	Lele	0	0	0	10	0	2	12	LC	C	ARY16114
Clarias meladerma (Bleeker, 1846)	Lele batu	0	0	0	6	2	2	10	LC	C	ARY16115
Siluridae
Silurichthys phaiosoma (Bleeker, 1851)	Lempok	0	0	0	11	2	2	15	NT	C	ARY16116
Bagridae
Hemibagrus sabanus (Inger & Chin, 1959)	Keting	0	0	0	27	10	9	46	DD	C	ARY16117
Mystus nigriceps (Valenciennes, 1840)	Lambenatap	0	0	0	7	3	1	11	LC	C	ARY16118
SYNBRANCHIFORMES
Mastacembelidae
Macrognathus aculeatus (Bloch, 1786)	Sili	0	0	0	10	0	3	13	LC	C&O	ARY16119
Macrognathus maculatus (Cuvier, 1832)	Sili	0	0	0	8	0	2	10	LC	C&O	ARY16120
ANABANTIFORMES
Osphronemidae
Trichopodus trichopterus (Pallas, 1770)	Sepat	0	0	0	8	0	3	11	LC	O	ARY16121
BELONIFORMES
Zenarchopteridae
Zenarchopterus dispar (Valenciennes, 1847)	Cucut	0	1	0	0	0	0	1	LC	O	ARY16122
Total		25	29	38	229	64	49	434

Note: LO: Lubuk Ombo, KS: Kampung Selamat, Kampung Tenggulun, AB: Alur Bujok, TB: Tenda Biru, TT: Tualang Tukul. Global conservation status according to IUCN. LC: least concern, NT: near threatened, and DD: data deficient. Potency: C: Consumption, O: Ornamental.

Figure 3. Fish species from Cyprinidae. (1) Crossocheilus cobitis; (2) Cyclocheilichthys apogon; (3) Hampala macrolepidota; (4) Labiobarbus leptocheilus; (5) Mystacoleucus obtusirostris; (6) Osteochilus vittatus; (7) Oxygaster anomalura; (8) Rasbora sumatrana; (9) Striuntius lateristriga. Scale bar = 50 mm.

Figure 4. Fish species from Channidae, Prestolepididae, Clariidae, Siluridae, Bagridae, Mastacembelidae, Osphronemidae, Zenarchopteridae. (10) Channa lucius; (11) Channa striata; (12) Prestolepis fasciata; (13) Clarias batrachus; (14) Clarias meladerma; (15) Silurichthys phaiosoma; (16) Hemibagrus sabanus; (17) Mystus nigriceps; (18) Macrognathus maculatus; (19) Macrognathus aculeatus; (20) Trichopodus trichopterus; (21) Zenarchopterus dispar. Scale bar = 50 mm.

Figure 5. Percentages of the different families of fishes in Merbau River.

Figure 6. Distribution of families, species and specimens according to sampling stations.

Table III. Diversity indices of fishes according to sampling stations in Merbau River.

Diversity variables	Lubuk Ombo	Kampung Selamat	Kampung Tenggulun	Alur Bujok	Tenda Biru	Tualang Tukul	Overall
Shannon-Wiener (H')	0.78	1.78	1.47	2.55	2.50	2.41	2.52
Evenness (E)	0.71	.91	.91	0.87	0.92	0.85	0.85
Dominance (C)	0.55	.18	.74	0.07	0.09	0.10	0.07

Table IV. Similarity index (%) of fishes in Merbau River.

Research stations	Lubuk Ombo	Kampung Selamat	Kampung Tenggulun	Alur Bujok	Tenda Biru	Tualang Tukul
Lubuk Ombo		4.00	25.00	18.18	22.22	11.76
Kampung Selamat			66.67	38.46	45.45	19.05
Kampung Tenggulun				50.00	50.00	10.52
Alur Bujok					82.35	84.85
Tenda biru						75.86
Tualang Tukul

Table V. Estimated parameters from length–weight relationship of fishes in Merbau River. a: intercept; b: slope of the linear regression; Cl: confidence limits; R²: coefficient of determination; K: condition factor.

Spesies	Total Length (mm)		Total Weight (g)		a	b	CI b of 95%	R^2	K	Growth pattern
	Min	Max	Min	Max
Channa lucius	146.47	448.48	76.25	497.68	0.0076	1.81	1.70–1.90	0.95	1.01	negative allometric
Channa striata	120.23	381.46	57.45	622.26	0.0037	2.01	1.60–2.43	0.97	1.01	negative allometric
Clarias batrachus	153.05	251.23	73.45	180.54	0.0063	1.85	1.73–1.97	0.99	0.99	negative allometric
Clarias meladerma	156.2	244.32	62.81	164.32	0.0017	2.08	1.79–2.37	0.97	1.01	negative allometric
Crossocheilus cobitis	89.12	142.77	7.28	27.28	0.0002	2.27	1.54–3.01	0.61	1.24	negative allometric
Cyclocheilichthys apogon	75.75	147.54	29.04	95.18	0.0097	1.83	1.67–2.00	0.95	1.00	negative allometric
Hampala macrolepidota	115.81	186.49	27.02	66.34	0.0007	2.18	1.72–2.65	0.90	0.93	negative allometric
Hemibagrus sabanus	107.78	185.13	11.33	66.62	0.0001	2.50	2.13–2.86	0.80	1.40	negative allometric
Labiobarbus leptocheilus	103.59	145.43	50.98	91.88	0.0094	1.85	1.61–2.09	0.94	1.24	negative allometric
Macrognathus aculeatus	133.24	292.75	12.64	67.43	0.0020	1.83	1.42–2.24	0.92	1.12	negative allometric
Macrognathus maculatus	86.18	307.01	8.72	68.21	0.0007	2.03	1.61–2.45	0.91	1.10	negative allometric
Mystacoleucus obtusirostris	97.85	143.23	45.24	95.56	0.0095	1.85	1.74–1.97	0.98	1.00	negative allometric
Mystus nigriceps	88.36	153.32	12.18	48.23	0.0012	2.10	1.69–2.50	0.93	0.96	negative allometric
Osteochilus vittatus	49.89	217.33	5.43	65.82	0.0001	2.51	2.33–2.69	0.92	1.47	negative allometric
Oxygaster anomalura	40.02	62.32	3.02	7.54	0.0073	1.62	1.38–1.87	0.90	0.99	negative allometric
Pristolepis fasciata	83.55	128.81	24.21	75.72	0.0010	2.31	2.02–2.60	0.93	1.02	negative allometric
Rasbora sumatrana	62.90	115.80	4.07	18.68	0.0002	2.40	2.06–2.73	0.86	0.78	negative allometric
Silurichthys phaiosoma	112.02	183.48	17.61	65.49	0.0002	2.36	1.51–3.22	0.73	1.26	negative allometric
Striuntius lateristriga	64.49	100.56	13.23	40.29	0.0004	2.48	2.29–2.66	0.96	1.02	negative allometric
Trichopodus trichopterus	65.87	95.67	7.19	12.45	0.0519	1.17	0.63–1.72	0.72	1.00	negative allometric

Table VI. Estimated parameters from relationship between total length (TL), standard length (SL) and fork length (FL) of fishes in Merbau River.

Species	SL (min-max)	FL (min-max)	Equation (TL-SL)	R^2	Equation (TL-FL)	R^2
Channa lucius	123.77–425.78	132.87–434.88	TL = 20.95 + 0.98 SL	0.98	TL = 12.62 + 0.98 FL	0.97
Channa striata	100.76–373.66	111.46–378.16	TL = 25.01 + 0.96 SL	0.97	TL = 9.57 + 0.98 FL	0.98
Clarias batrachus	145.31–241.43	150.43–248.11	TL = 20.11 + 0.93 SL	0.98	TL = 15.60 + 0.93 FL	0.99
Clarias meladerma	145.70–237.82	150.88–240.02	TL = 14.84 + 0.97 SL	0.98	TL = 6.72 + 0.99 FL	0.99
Crossocheilus cobitis	65.67–120.21	80.67–139.44	TL = 38.72 + 0.84 SL	0.75	TL = 12.67 + 0.92 FL	0.94
Cyclocheilichthys apogon	55.94–130.69	64.73–134.16	TL = 24.24 + 0.92 SL	0.94	TL = 16.37 + 0.93 FL	0.96
Hampala macrolepidota	105.81–176.49	107.31–177.99	TL = 37.06 + 0.68 SL	0.69	TL = 20.14 + 0.82 FL	0.83
Hemibagrus sabanus	90.12–153.95	100.67–164.82	TL = 36.84 + 0.85 SL	0.89	TL = 24.84 + 0.87 FL	0.90
Labiobarbus leptocheilus	75.35–127.32	85.19–136.36	TL = 33.78 + 0.89 SL	0.85	TL = 20.51 + 0.91 FL	0.82
Macrognathus aculeatus	128.74–288.25	130.14–290.65	TL = 5.22 + 0.96 SL	0.92	TL = 2.47 + 0.99 FL	0.99
Macrognathus maculatus	70.89–290.81	74.08–239.91	TL = 3.24 + 1.03 SL	0.92	TL = 4.36 + 1.07 FL	0.95
Mystacoleucus obtusirostris	83.50–134.38	90.39–138.07	TL = 20.38 + 0.93 SL	0.91	TL = 11.31 + 0.98 FL	0.94
Mystus nigriceps	74.94–145.21	81.84–149.85	TL = 14.68 + 0.96 SL	0.98	TL = 6.29 + 0.99 FL	0.96
Osteochilus vittatus	42.94–205.55	39.04–196.43	TL = 27.44 + 0.95 SL	0.93	TL = 17.00 + 0.96 FL	0.89
Oxygaster anomalura	31.76–57.67	37.83–62.92	TL = 5.90 + 0.98 SL	0.81	TL = 0.61 + 1.02 FL	0.98
Pristolepis fasciata	71.35–122.61	81.65–128.43	TL = 23.98 + 0.84 SL	0.97	TL = 3.00 + 0.98 FL	0.98
Rasbora sumatrana	47.50–109.19	51.65–113.63	TL = 19.25 + 0.96 SL	0.86	TL = 19.25 + 0.96 FL	0.86
Silurichthys phaiosoma	95.69–168.62	103.38–165.67	TL = 27.44 + 0.95 SL	0.85	TL = 10.49 + 1.11 FL	0.92
Striuntius lateristriga	50.40–92.01	56.08–96.56	TL = 37.06 + 0.68 SL	0.69	TL = 20.13 + 0.82 FL	0.83
Trichopodus trichopterus	58.37–89.17	60.89–91.57	TL = 9.40 + 0.97 SL	0.91	TL = 3.17 + 0.99 FL	0.98

Figure 7. Diagram of the IUCN red list status (A) and Venn diagram of potency (B) of 21 species of fish in Merbau River. LC: least concern, DD: data deficient, and NT: near threatened. Potency: C: Consumption, O: Ornamental.