Abstract Forty-eight streams were surveyed during four aerial 1080 operations in New Zealand’s South Island to quantify the number of 1080 baits falling into streams. Bait size used in each operation varied considerably: small (2 g) baits in Marlborough, medium-sized (6–7 g) baits in Canterbury and the West Coast, and large (11 g) baits in Lewis Pass. The number of baits found in streams varied widely, and was related only to bait size, with more of the small baits found in streams than the large baits. There was no relationship between stream width or canopy cover and the number of baits found within a stream. These findings suggest that the potential number of baits falling into a stream cannot be calculated from the bait application rate and the stream size. The fate of submerged 1080 baits was also examined in a laboratory flow tank. Submerged baits fragmented within 3–4 days. 1080 was rapidly leached from submerged baits: almost 50% of original 1080 had leached after 5 h, and >90% after 24 h. Such rapid leaching reflects 1080’s high solubility. This finding has implications for water quality monitoring programmes used during 1080 drops, as samples should be collected within 4–8 h of potential contamination to detect presence of 1080.
Keywords sodium fluoroacetate; 1080; water quality; monitoring
New Zealand Journal of Marine and Freshwater Research, 2006, Vol. 40:
159–167
0028–8330/06/4001–0159 © The Royal Society
of New Zealand 2006
M05060; Online publication date 21 February 2006. Received 6 September
2005; accepted 2 November 2005
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