Michael Schlüter

An Aquatic journey to the Kapuas River in West Kalimantan Part 2


Our next biotope, by car 130 kilometres from Pontianak was 6-8 meters wide and approx. 1,5 meters deep, and in fact of raining the river was very fast floating. Here we did catch Trichopsis vittatus, Hemirhamphodon poponognathus, Rasbora cf. volzi, Rasbora spec. as well as a Mastacembelus species. Biotope number 3 lay in a hill landscape with beginning of fire clearance for paddy fields.
Biotope 3 a mountain stream
Biotope 3 a mountain stream © 2001 Michael Schlüter
It looked like a river you normally see in the mountains. The river had many varied zones with deep of 20 to 100 cm and a width of averagely 6 meters. Stone, gravel and sand zones alternated. In spite of this strong structure wealth we caught only 2 barbs and a Nemacheilus species, perhaps Nemacheilus borneesnsis. I had hoped for some hillstream loaches. But we did not find any. Perhaps the river with a temperature of 28,5 °C in spite of the strong movement had not enough oxygen for these fish? We have measured only the pH factor with 6,8 and the conductance with 37 µS/ccm³. Regional this small river was very delightful. The next biotope, 159 kilometres by car from Pontianak did surprise me. A Hemirhamphodon species I had not seen before. I had read from this biotope already with Roberts (1989). The species in this river was Hemirhamphodon phaiosoma. I also wanted to catch these kind, however, did not know how they look. As first H. kapuasensis occurred to me to this species who also has a red collateral line. The dorsal fin of Hemirhamphodon phaiosoma was much longer than of H. phaiosoma. This small river lay in the hill country with primary forest and beginning fire clearance at the end of a village and was used as a washing place. Here it was 2 to 4 meters wide and 30 to 100 cm deep. The fast floating water was ending in a small lake. It was weakly yellowish clearwater and had on 30/09/01 at 5.15 o clock p.m a temperature of 27 °C, pH factor 6,7 with 2 µS/ccm³. Here we could catch by push net Barbus spec., Rasbora sumatrana, R. sarawakensis, Acantophtalmus shelfordi, Nemacheilus selangoricus, Doryichthys spec., Channa striata and the Hemirhamphodon phaiosoma.. From also interesting Doryichthys ssp. we could catch only a unique specimen in almost five hours. This freshwater pipefish found under the hollowed bank area.
For the next day we planned our first trip of several days to Sintang. We wanted to leave our already caught fish in linen tubs and water-reserves for washing in the bathroom of our pension. Most fish caught by us were well fed. For the daily water change we used the water from the administration. This water came according to Kasigen from a river and was suitable with a pH factor of 7,2 with 22 µS/ccm³, best for the clear water fish. For the black water fish we got the water of our first catching side. This was already dirtied on account of farming and clearing, we could state in the partly strong algae growth and the conductivity high, unusual for black water. Because we have caught no ill fish, the water seemed to us been suitable best, not at least for reason it lay surely near. For the feeding of the fish we set on eggs of brine shrimp and attracted small ants which ran in our bathroom, with some Mango. So we could feed several times a week. Our fifth catching site was 360 kilometres far form Pontianak and lay in a hardly settled area of approx.
Biotope 5 a small blackwater brook
Biotope 5 a small blackwater brook © 2001 Michael Schlüter
10 kilometres behind Sekadau with secondary forest and our first Nepenthes at the natural location. Also here wood was hit. A small, strongly floating, turbid blackwater river was stopped by the street and flooded the bank.
Rasbora kalochroma Rasbora sumatrana
Rasbora kalochroma Biotope 4© 2001 Michael Schlüter     Rasbora sumatrana Biotope 7 © 2001 Michael Schlüter
Here we could catch Rasbora kalochroma, a silurid catfish and young fish of a Betta species. The biggest Rasbora had a length of 6 cm and were numerous in the turbulent area before the subway of the street. With a water temperature of 27 °C at 6 o'clock p.m. we could measure a pH factor of 3,78 and 22 µS/ccm³. The Rasbora impressed us with their dark red body colour and therefore were taken with us. After we stood to an overnight accommodation in a little bit peculiar hotel in Sekadau, witch outed as a disorderly house, we drove northwest on a street to an isolated mountain, shortly behind Sintang. Here we caught in two small clear water rivers. In first (biotope 6) we caught Rasbora pauciperforata, Barbus pentazona and Luciocephalus pulcher. In the second small river (biotope7) we could catch Hemirhamphodon poponognathus and two species of Rasbora.
Biotope 7 a small forest stream
Biotope 7 a small forest stream © 2001 Michael Schlüter
On our way back after Pontianak our next overnight accommodation was essentially more comfortable in Sintang. Nevertheless, we also used here our mosquito nets around the pervasive insects to refuse. In the next morning, 03/10/01 we started early, because we stood in the direction of the type locality of Hemirhamphodon kapuasensis. Naturally we wanted to look the way there around other biotopes to catch fishes. Our eighth biotope was again beautiful, a clearwater river with a temperature of 25 °C, pH factor 4,7 and 10 µS/ccm³. Here we could catch in single quantities Barbus pentazona, some Rasbora spec. and R. dorsiocellata as well as Nandus nebulosus, Pristolepsis spec., Mastacembelus spec. and a Mystus species. The next discovery site was a clear ditch in which we found Rasbora kalochroma, R. pauciperforata, R. sp. aff. sumatrana   as well as many Trichogaster trichopterus trichopterus.

Part 3

© 2002 Michael Schlüter

Home || Species || Photos || Links || Diverse || E-Mail || Guestbook