Bush clearing threatens critically endangered pipefish
One of the rarest animals in Africa, found exclusively in a couple of estuaries on the Eastern Cape’s Sunshine Coast, is being threatened by a growing trend of illegal land clearing in river catchments.
The problem was revealed in a new study by a Rhodes University group that focuses on the rehabilitation of the subtropical thicket vegetation which blankets the home of the critically endangered estuarine pipefish east of Algoa Bay.
The lead author of the Rhodes Restoration Research Group study, Nicholaus Huchzermeyer, said urgent steps had to be taken to halt the bush clearing, and prevent the final demise of the species.
Declared extinct in 1994, the estuarine pipefish was rediscovered in the Kariega Estuary in 2006 and this “return from the dead” earned it the nickname the Lazarus fish.
But now, the little creature — about 110mm long — is struggling for survival again.
Huchzermeyer said the study had focused on the catchment areas of the West Kleinemonde River and East Kleinemonde River.
“We found that clearing of subtropical thicket for pineapple fields, cattle pastures and sand mining has increased sharply over the last decade in this area.
“Large areas of this bush had been historically cleared but clearing activities are now encroaching closer to the rivers on steeper slopes within the protected buffer.
“Left intact, this bush protects rivers from being polluted by run-off from fertilisers and pesticides from cultivated fields.
“It also creates a buffer which helps prevent rivers from silting up with eroded soils.”
He said these areas were protected by existing laws but these needed to be enforced.
He said when catchment bush was cleared, the quality of the river water deteriorated and this affected the eelgrass habitat in the estuaries where the pipefish usually live, and the availability of animal plankton on which it fed.
“It is very likely that the niche habitats and food sources required by the pipefish are disappearing due to upstream impacts and in turn pipefish populations have been extirpated [destroyed].”
Huchzermeyer said the historical range of the species included the Bushman’s, Kariega, Kasouga and Kleinemonde West and Kleinemonde East estuaries.
“A 2022 study checking for pipefish DNA in the water concluded that the species is likely locally extinct in the Kasouga and both Kleinemonde estuaries.
“However, researchers detected the estuarine pipefish in the Kariega and Bushman’s estuaries using both environmental DNA and physical sampling methods. The total surviving population is not known, but the estuarine pipefish is certainly one of the rarest and most threatened animals in Africa.”
Under the National Environmental Management Act, the regulatory buffer for bush clearing is set at 32m, under the Water Act it is 100m and for wetlands and pans, which often form a part of catchments, the legal setback is 500m.
Huchzermeyer said land users in river catchments who did not comply with these laws should be severely penalised.
Eastern Cape economic development and environmental affairs department spokesperson Ncedo Lisani said his department prioritised conservation of high-risk species, particularly those that were critically endangered like the estuarine pipefish, and worked to minimise negative effects on them.
“In this regard, any unlawful clearance of valley thicket that comes to [the department’s] attention is thoroughly investigated.”
He said where necessary, the forestry section of the national department of forestry, fisheries and environment was also notified for the necessary action to be taken.