Macro-invertebrates, zooplankton and water quality variables were sampled at 33 wetlands near Perth, Western Australia, in January-February 1989. Wetlands were classified and ordinated using the invertebrate data. Correlations of environmental variables with the ordination were calculated and the importance of seasonality and geomorphology of the wetlands were investigated. The wetlands were also classified and ordinated using the chemical data. Analysis of variance was used to compare species richness, abundances of all invertebrates, macro-invertebrates, copepods and total phosphorus levels among groups. Six groups of wetlands were identified from the invertebrate data, two of which were outliers on the basis of very low pH and high salinity, respectively. The majority of the wetlands grouped on the basis of their degree of nutrient enrichment and colour. The analyses of chemical data gave similar groups. The coloured wetlands and least nutrient enriched non-coloured wetlands were identified as being closest to the probable state of wetlands prior to European settlement. The greatest numbers of rare species were found in wetlands from these two groups. Species richness was significantly higher in the moderately enriched wetlands than in any other group but decreased in the most enriched wetlands where abundances of invertebrates were highest. Changes in community composition among the groups of wetlands are discussed. The most highly nutrient enriched wetlands were dominated by cosmopolitan species with high abundances, whereas less enriched and coloured wetlands had species with more restricted distributions and lower abundances.

Summary Identifying the fate of birds’ nests and the causes of breeding failure is often crucial for the development of conservation strategies for threatened species. However, collecting these data by repeatedly visiting nests might itself contribute to nest failure or bias. To solve this dilemma, automatic cameras have increasingly been used as a time-efficient means for nest monitoring. Here, we consider whether the use of cameras itself may influence hatching success of nests of the Black-tailed Godwit Limosa limosa at two long-term study sites in northern Germany. Annually between 2013 and 2019, cameras were used to monitor godwit nests. In 2014 and 2019, nests were randomly equipped with cameras or not, and nest survival checked independently of the cameras. Nest-survival models indicated that survival probabilities varied between years, sites and with time of the season, but were unaffected by the presence of cameras. Even though predation is the main cause of hatching failure in our study system, we conclude that predators did not learn to associate cameras with food either when the cameras were initially installed or after they had been used for several years. Cameras were thus an effective and non-deleterious tool to collect data for conservation in this case. As other bird species may react differently to cameras at their nests, and as other sets of predators may differ in their ability to associate cameras with food, the effect of cameras on breeding success should be carefully monitored when they are used in a new study system.

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