RADIONUCLIDE UPTAKE BY RED DEER (CERVUS-ELAPHUS) ON MOUNTAIN GRAZING

Forty-two red deer (Cervus elaphus) were shot during the 1992 annual c ull in Glenveagh National Park, Ireland. Samples of rumen, kidney and faeces were removed from each animal. Kidney samples were used to esti mate flesh radiocaesium (Cs-137) concentrations and the 95% confidence interval for the mean was 203 +/- 12 Bq kg(-1). The maximum recorded Cs-137 concentration in kidney was 367 Bq kg(-1) (fresh weight). The a ltitude of the cull, the age and sex of each animal were recorded. Nei ther age nor sex correlated with concentrations of Cs-137 in rumen, ki dneys or faeces. Despite the limited altitudinal range of the study an d the free ranging behaviour of deer, there was a highly significant p ositive correlation between rumen, kidney and faecal Cs-137 concentrat ions and the altitude of the cull. K-40 concentrations in rumen, kidne y and faeces did not correlate with the altitude of cull, age or sex o f slaughtered animals. Significant Cs-137 concentration differences we re identified in the sequence: rumen < faeces = faeces. Cs-137 concent rations in rumen, kidney and faeces for individual animals were all si gnificantly correlated. Statistical testing showed that the concentrat ion sequence for K-40 was: rumen < kidney = faeces; a sequence which d iffers from that of Cs-137. A comparison of ratios test for rumen:faec al ratios demonstrated that significantly more Cs-137 was excreted in faeces than was the case for K-40. The concentration of Cs-137 excrete d in faeces relative to concentrations in forage (rumen), is approxima tely twice that for K-40. Linear regression of faecal Cs-137 concentra tions (y) on kidney concentrations (x) was carried out, the regression equation is y = -86.90 + 0.97x. This equation (R(2) = 0.73, F-1,F-40 = 107) may be used to predict Cs-137 concentrations in flesh by measur ement of faecal concentrations. This is a useful preliminary assessmen t method, particularly with herds of wild animals that prove difficult to capture for in vivo monitoring.