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Six small constructed ponds (surface area 500-7500 m 2 , catchment area 28-158 ha) in rural and native forest catchments in the Auckland region had poorer water quality than the streams they replaced. Temperature (24°C) and dissolved oxygen (DO) (4 mg/litre) criteria were exceeded for up to 46% and 84% of days, respectively, during a critical 40-day summer period. The poor conditions found in ponds, even within undeveloped native forest catchments, indicated that the physical characteristics of ponds (e.g., lack of shade, organic sediments) affected water quality independently of other factors (e.g., land use, riparian protection). The frequency and severity of the exceedences were related to pond size, retention time, and catchment land use; the most degraded conditions were found in rural ponds with largest surface areas and longest retention times. Ponds affected water quality and macroinvertebrate communities downstream. Exceedences of temperature and DO criteria occurred more frequently and were more severe downstream than upstream of ponds. Ponds in rural catchments increased mean daily stream temperatures 3.1-6.6°C during the critical summer period, and temperature differences were three times higher than those in bush catchments (0.8-2.0°C). Elevated M04122;temperatures were observed for hundreds of metres downstream owing to the slow rate of cooling (1°C/ 100 m), expanding the extent of adverse effects well beyond the "footprint" of the pond. Macroinvertebrate community composition (sample area 1-3 m 2 ) and values of four commonly used metrics appeared to be significantly affected by ponds in rural and native forest catchments. These finding have important management implications that should lead to modifications (e.g., breaching dams) of the estimated 4500 existing ponds in the Auckland region, where possible, and restrictions on proposals for new "o

Macroinvertebrate communities in hardbottomed (HB) and soft-bottomed (SB) streams were compared to address questions on sample substrata, sample area, and data interpretation. Communities at HB and SB reference sites (native bush catchments) were distinctly different. SB reference sites had 50% of the total taxa, 33% of the Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxa, and significantly lower Macroinvertebrate Community Index (MCI) and Semi-Quantitative MCI (SQMCI) scores than HB reference sites. Ten EPT genera were abundant (>20 individuals per sample) at HB reference sites compared with one EPT genus (Zephlebia) at SB reference sites. The densities of macroinvertebrates at SB reference sites were <10% of those at HB sites indicating the need to sample a larger area to obtain a representative sample. SB sites with severe urban and rural land use disturbance had significantly lower metric values than SB reference sites. The SQMCI was the only metric sensitive to moderate disturbance, and multivariate ordination further supported the value of relative abundance data in detecting moderate impairment in SB streams. Hand sampling of submerged wood added 16-40% more taxa in total, and 11-44% more EPT taxa to sweep-net samples, indicating the importance of directly sampling wood in SB streams. The results supported separate collection methods and data interpretations for HB and SB streams proposed in recently published New Zealand protocols.

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