Smoothing rockies’ road

Alien fish and human-wrought habitat changes are threatening the Eastern Cape rocky, an almost extinct member of the rare labyrinth fish family endemic to just six Eastern Cape river systems. Mike Burgess spoke to Jim Cambray and Greg Briggs, on the frontlines of the fight to save this unique species.
Issue date: 06 June 2008

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The first Eastern Cape rocky recorded by the French Count Castelnau in 1861 had resided in the River long before Port Alfred was established at its mouth. T hen the Cape was a rugged wilderness with finely balanced freshwater ecosystems. In the deeper pools lurked visitors from the sea, including giant mottled eels (Anguilla marmorata), apex predators reaching around 14kg.

However, the shallower rocky glides of this unspoilt wilderness were the domain of another ferocious apex predator, the rocky. Despite only reaching a maximum length of 30cm, with its big, strong mouth and ability to wedge itself between rocks before darting out at passing prey, the rocky had been able to hold its own in rivers between the Nahoon in the north and the Kowie in the south, 160km apart from mouth to mouth. he rocky’s tiny range is reflected in its scientific name. Its genus (Sandelia) is named after the area’s 1800s Xhosa warrior Chief Sandile, while the species (bainsii) is named in honour of Eastern Cape geologist, engineer and hunter Andrew Geddes Bain. But it’s not only the rocky’s locality that’s unique – it also belongs to the rare family of Anabantidae, also known as labyrinth fish.

The name is derived from the unique breathing organs above their gills, known as the labyrinth chambers, which enable them survive in swamps and streams with low oxygen levels.

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Despite such adaptations the rocky, like its Western Cape cousin, the Cape kurper and other freshwater fish such as the border and amatola barb, proved very fragile in the face of humans’ thoughtless manipulation and abuse of its environment. Humans who harm and help Less than 150 years after being discovered in the Kowie River, the rocky lives in a transformed world, threatened by the impact of dams and weirs; increased informal settlements; agricultural practices such as water abstraction and siltation, specifically from bush clearing for pineapple lands; mega state-funded intercatchment hydrological manipulations; and pollution by pesticides, herbicides, detergents, animal dip, and human waste.

Perhaps the worst threat of all is the introduction of alien predatory fish and various species of alien flora. Fortunately, in the rockies’ darkest hour, a number of enlightened individuals and organisations are doing what they can to save this unique fish. A Kowie tributary, the Bloukrans, is situated in the Blaauwkrantz Nature Reserve, founded three years ago to protect one of the last remaining southern rocky populations.

The reserve is the brainchild of Jim Cambray, specialist scientist at the Albany Museum in Grahamstown, who had difficulty of getting finance for the project, eventually funded by the Algoa Regional Services Council. Jim first observed the rocky in the early 1970s. In 1984 he settled in Grahamstown and quickly realised the rockies had seriously declined in numbers.

He immediately began studying their reproductive behaviour and early life history, of which very little was known. In fact, Jim is probably best known for capturing the rocky’s unique mating dance on film. Kowie rockies are perfectly willing to breed in Jim’s fish tank. The male grasps a female with special barbs on the sides of his head, and after an elaborate dance, the adhesive, fertilised eggs settle on the pebble bed of the tank. The male then guards the nest so aggressively Jim has to remove the females from the tank. When the eggs eventually hatch, the juvenile rockies are only 3mm in diameter, with adhesive threads on their heads to hold them in place at the nesting area. More research on the breeding behaviour of the Tyume River rockies was conducted by Dr Monde Mayekiso.

Population surveys Such scientific research, however, was only part of understanding the rocky. Populations in the wild were surveyed based on historical and contemporary sightings on the Kowie, Fish, Keiskamma, Buffalo and Nahoon river systems. This was critical in establishing how best to protect rockies – farm dams are important possible reserves, as rockies breed in still water – or where best to initiate community awareness programmes. This work was to prove bittersweet.

The surveys of a number of rivers were disappointing. In the Nahoon, only one rocky was found in 10 surveys and in the Fish River some populations had disappeared. Fortunately, enthusiasts from the East London Museum, including Greg Brett, discovered some encouraging developments. Greg’s involvement with the rocky began in 1983, when a man appeared at the front desk of the museum with a bucket of rockies he claimed to have caught on the Gulu River south of East London – Greg’s subsequent attempts to find rockies there failed.

Greg’s surveys of the northeastern reaches of the rocky’s known distribution, were instrumental in protecting two Buffalo River tributary populations in 2000, when they helped stop the Department of Water Affairs and Forestry (DWAF) transfering water from the bass-filled Wriggleswade dam to one particular tributary, and the building of a weir on another. This ensured no alien predators reached a particular population of rockies. In the same year a fisherman brought another bucket of Gulu River rockies to the museum, and a resurvey at another location discovered healthy populations.
Later, rumours of fish that looked like crosses between bass and tilapia in the Igoda River led to another successful survey. Both were extremely significant finds, says Greg. “With no alien fish populations in these rivers, we’re talking about a rather pristine environment in small streams, which makes them easier to manage,” he explains.

“The populations are good and, perhaps more importantly, are genetically similar to those of the Buffalo area, but distinct from other southwestern populations.” Community involvement News of these new rocky finds was greatly exciting to Jim. He now had a little good news he could weave into community awareness campaigns, which included erecting displays in museums across the Eastern Cape, educational initiatives and the publication of numerous articles, nationally and internationally. All this fell under the Albany Museum’s Eastern Cape Rocky Conservation Programme, which has now attracted the attention of organisations such as the World Wildlife Fund (WWF) and Mazda Wildlife Trust.

Besides direct protection and scientific study of the species, the programme’s goals are perhaps best illustrated by the Kowie Catchment Campaign (KCC), a local community initiative launched by the Makana Environmental Forum to contribute to the International Year of Freshwater in 2003. Central to the campaign was the involvement of sectors of the community in the Kowie River catchment area, including farmers who adopted stretches of the catchment area to maintain. The KCC emphasised the importance of holistic catchment management, and serves as a benchmark for what can be done to save our freshwater resources. In 2007 it received the African Geographic, Nedbank Green Trust Unsung Heroes Award; in the same year it won a Special Merit Award from the Rotary Club of Grahamstown. “You can’t start with the fish, you need to manage the entire catchment and involve the communities,” explains Jim. “In the end, mismanagement will mean no freshwater fish.”

Resistance and sabotage But disturbingly, a new KCC rocky sanctuary in Grey Dam near Grahamstown – stocked with rockies Jim bred in captivity – elicited some stiff resistance from sections of the community that wanted to introduce alien angling fish into the dam. It was then discovered that alien fish had in fact been illegally, and maybe spitefully, released into the dam, spelling certain doom for the rockies here. “It’s frustrating when such hard work can be upset by one fool and a bucket of aliens,” says Jim. The most serious threat facing rockies, the lethal cocktail of human arrogance and ignorance, is alive and well.

Other sources: www.desertfishes.org; www.ru.ac.za; www.panda.org.za; www.scienceinafrica.co.za; www.springerlink.com and A Complete Guide to the Freshwater Fishes of Southern Africa by Paul Skelton (Struik Publishers, 2001)