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Individual study: Effects of artificial manipulation of nesting substrate on nest-site selection and breeding success of common terns Sterna hirundo nesting on a concrete breakwater near Port Colborne, Lake Erie, Ontario, Canada

Published source details

Richards M.H. & Morris R.D. (1984) An experimental study of nest site selection in common terns. Journal of Field Ornithology, 55, 457-466


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Provide artificial nesting sites for ground and tree-nesting seabirds Bird Conservation

A small replicated, controlled study from May-August in 1982 on a concrete breakwater in Port Colborne, Canada (Richards & Morris 1984), found that common terns Sterna hirundo nested at higher densities on two plots enhanced with clumps of mossy stonecrop and driftwood added (62% of 166 clutches in these plots), compared to plots layered with gravel (29% of clutches) or control plots of bare concrete (9% of clutches). Enhanced plots were also colonised earlier. Average clutch size and hatching rates were similar between plots (2.4-2.5 eggs/clutch and 76-86% hatching success), but the average number of chicks fledged per pair was significantly higher in enhanced (1.6) and control (1.3) plots than in gravel-layered plots (0.6). The breakwater was divided into six 5 ? 7 m plots, with two plots for each treatment.