With kind per­mis­sion from the PCBA we here pub­lish an arti­cle, which can be found on the home­page of PCBA. We fol­low the endavours of the PCBA and the con­ser­va­tion of the indone­sian species of parosphromenus with close and warm inter­est, and will con­tinue to sup­port their work, when­ever possible.

That efforts such as PCBA exists, and care for the parospromenus species — as well as other black­wa­ter species — is of very big importance.

The con­ser­va­tion effort for black­wa­ter fish by PCBA

By adyah ningtyas– April 2021

Indone­sia is home to the biggest area of peat swamp forests in the world. The forests are widely spread in Suma­tra and Bor­neo. The floor of these forests is moist sat­u­rated soil that is called peat. It is an acidic layer that is made of dead leaves, woods and other organic mat­ters that do not decom­pose fully. To form a sta­ble peat for­est takes thou­sands of years. Unfor­tu­nately, it has been threat­ened by devel­op­ment and eco­nomic drive as many of Indonesia’s peat swamp forests have been turned into indus­trial forests and mono­cul­ture plan­ta­tions, such as palm oil plantations.

Another threat to these forests comes in the form of uncon­tain­able wild­fire. Con­sid­er­ing the com­po­si­tion of the peat for­est that con­tains a high amount of organic mate­r­ial, a small fire can be a big dis­as­ter. Fire can remain under­neath the sur­face for a long period of time turn­ing the fer­tile ground into a waste­land. The recent irre­spon­si­ble anthro­pogenic causes only fur­ther insti­gate the fire and speed up the land devastation.

Mean­while, peat­land forests play a crit­i­cal role in the car­bon cycle. The amount of the organic mate­r­ial that is accu­mu­lated in the peat layer allows peat swamp for­est to store a sig­nif­i­cant amount of car­bon. Once it is logged and erad­i­cated, the amount of car­bon released into the atmos­phere vaults up. This speeds up global warm­ing and trig­gers cli­mate change as we have been expe­ri­enc­ing today. Apart from its global effect, the loss of peat swamp for­est also affects the organ­ism in its locality.

Inside the peat­land forests strives an unpar­al­leled ecosys­tem that can­not be eas­ily recre­ated. Dur­ing the rainy sea­son, the floor of the for­est is flooded for sev­eral months. The water remains even dur­ing the dry sea­son, form­ing long term shal­low ponds with soft acidic fresh­wa­ter. On the appear­ance, the water is of stained brown colour owing to the tan­nins leach­ing from dead leaves and other organic mat­ters, includ­ing the peat itself. This colour earns its name, blackwater.

Black­wa­ter is unique in com­po­si­tion. This water is formed by rain­wa­ter with very lit­tle min­eral con­tent result­ing in very low con­duc­tiv­ity. Black­wa­ter is also very low in pH, around 2.9 to 5.5. These make the black­wa­ter pond also a unique ecosys­tem. Many organ­isms make it their home. Some of those organ­isms are native Betta and Parosphromenus fish. Since the ponds in one area of the for­est may have a com­pletely dif­fer­ent ecosys­tem from the ones around it, they can have dif­fer­ent species of fish. A river, a hill or just a slightly big­ger stream of fresh basal water can act as a geo­graph­i­cal bound­ary that hin­ders species to meet one another. In some cases, the species on one side of a river is com­pletely dif­fer­ent from the one on the other side.

Con­sid­er­ing the high sin­gu­lar­ity of the ponds in each area, habi­tat loss in one area as above men­tioned may irre­versibly erad­i­cate the whole remain­ing fish species. With this in mind, PCBA, with the expert sup­port from the Parosphromenus Project, is com­mit­ting its power to con­serve Indonesia’s endan­gered black­wa­ter fish species. Cur­rently, we have a fish room con­tain­ing 75 tanks of var­i­ous sizes that are ded­i­cated to con­ser­va­tion breed­ing of those fish. At present, PCBA cares for sev­eral species of both Parosphromenus and Betta. Its pri­or­ity includes:

1. P. ornat­i­cauda
2. P. deiss­neri
3. P. bin­tan
4. P. sp Jambi/​Tangkit
5. B. bur­di­gala
6. B. ruti­lans
7. B. spi­lo­to­gena
8. B. man­dor
9. B. min­iopinna

These fish are among Endan­gered (EN) and Crit­i­cally Endan­gered (CR). PCBA acquires the found­ing indi­vid­u­als from the local highly threat­ened ponds in the vicin­ity of palm oil plan­ta­tion and or indus­trial for­est. Com­ing from extremely soft and acidic water in their nat­ural habi­tat, it took around the clock obser­va­tion to set up a suit­able water envi­ron­ment. To recre­ate the per­fect nat­ural habi­tat in the peat swamp for­est was a real chal­lenge. It also requires total ded­i­ca­tion to ensure the breed­ing suc­cess of the fish. Nev­er­the­less, the dili­gence of the team resulted in applaud­able devel­op­ment in fish species con­ser­va­tion. In PCBA’s fish room, the fish have incred­i­bly devel­oped their pop­u­la­tion. Today, most of these species have spawned and many of the fry are free-​swimming and independent.

In the plan­ning stage of our endeav­our in con­ser­va­tion breed­ing of Indonesia’s black­wa­ter fish, the Parosphromenus Project (PP) played a vital role. In May 2020, Jochen Men­ner of PCBA con­tacted PP for the first time and received a warm response and an offer of expe­ri­ence and exper­tise in set­ting up PCBA’s fish room. It was Went­ian Shi who replied to the email. Since then, Went­ian Shi, as well as Yuhan Ji, has been PP’s rep­re­sen­ta­tives to guide PCBA through the ini­tial plan­ning of the fish room. He has been the one who sug­gested the fish tank sizes and the species to keep. He has also offered help in the acqui­si­tion of found­ing individuals.

Cus­tom sized aquaria

In Decem­ber 2020, PCBA ordered the aquaria from a local maker with the sizes that have been rec­om­mended by PP. Some sizes were adjusted after a few con­sid­er­a­tion. The aquaria were set up in the fish room not too long after that. By this stage, PCBA had con­sid­ered a few options in regard to fil­tra­tion and air sup­ply and it was decided to work with sim­ple air-​powered sponge fil­ters. The adjust­ment to the water para­me­ter as men­tioned above fol­lowed after that.

Installed aquaria

Due to, the COVID-​19 restric­tion applied in the immi­gra­tion law, the plan of inte­grat­ing Went­ian Shi into the ini­tial prepa­ra­tion had to be adjusted. We acquired the fish from some local sources and con­tinue with the con­ser­va­tion breed­ing plan with­out the phys­i­cal pres­ence of PP. How­ever, the sup­port in knowl­edge and exper­tise from the Parosphromenus Project continues.

Betta min­niopinna guard­ing the nest

To learn more about this black­wa­ter fish project, please see this web­site pri​ge​nark​.com.