Investigation into the Ecological and Toxicological Constraints on a Population of Lesser Flamingos (Phoeniconaias minor) at Kamfers Dam in Kimberley, South Africa

This study investigates the threats to a breeding population of lesser flamingos (Phoeniconaias minor) at Kamfers Dam in Kimberley, South Africa. The main threats include water quality/quantity, algal food source abundance and exposure to contaminants accumulating in the dam. Water quality testing and analysis of historical water quality reports were used to analyze the effects of the physical and chemical parameters on the algal assemblage at Kamfers Dam and determine if changes in the water quality could predict changes in the algal assemblage. Arthrospira fusiformis, the flamingos preferred food, was positively correlated with conductivity, total dissolved salts and negatively correlated with total phosphorous. While significant correlations were found, attempts to develop a model for predicting algal community composition were unsuccessful due to strong multicollinearity among the water chemistry parameters. Lesser flamingos were trapped at Kamfers Dam and blood and feather samples were collected to analyze for trace element and organochlorine exposure. Blood samples were also collected from nestling African fish eagles (Haliaeetus vocifer) in the Kimberley area to analyze for organochlorines. Concentrations of cadmium, copper, chromium, iron, lead, mercury, nickel, selenium and zinc were detected in the flamingo feathers. Lesser flamingo blood was positive for both cadmium and lead. Although some trace element concentrations were considered high in comparison with other species, none of the metals appear to be having a negative effect on the health of the birds. Lesser flamingo plasma was positive for concentrations of 20 organochlorines and African fish eagle plasma was positive for 8 organochlorines. DDT was found in 16 (n = 17) flamingo samples and all 13 fish eagle samples while PCBs were found in 15 of the flamingo samples and 6 of the fish eagle samples. Several eagles had 4,4\u27-DDT in their plasma indicating recent exposure although the source is unknown, these nests were grouped closest to Kimberley. While concentrations found in both lesser flamingos and fish eagles were mostly below levels of concern, the lack of published data on 2,4\u27-DDE concentrations in wildlife and toxicity values for this specific degradation product point to a need for monitoring this analyte. Continued monitoring of the water quality of Kamfers Dam as well as concentrations of organochlorines in the avifauna in the Kimberley area is warranted