Reading path: Coastal field methods →
Describe the search, not just the result
Write what area you examined, how long you looked, and what method you used before stating that a target was not detected. “No sea stars” gives little context; “No sea stars observed during a ten-minute visual scan of the marked north wall” gives a defined search and result. If you inspected only accessible surfaces or one part of a pool, say so. The record is about what the method detected on that visit. It does not establish that the organism was absent from the wider shore or hidden parts of the habitat.
Record conditions that affect visibility
Conditions determine how much of a site could be examined. Note water clarity, depth, glare, surge, exposed or submerged surfaces, and any disturbance that limited the search. If a target could hide beneath stones or inside crevices, specify whether you looked there and whether doing so was allowed and safe. “Not seen” during clear water and a careful inspection has a different context from “not seen” through cloudy water during a short visit. Keep the language descriptive rather than converting the observation into a conclusion about population decline.
State the target and detection rule
Define what counted as a detection, especially when the subject may be small, partial, or difficult to distinguish. Were you recording any visible individual, only organisms above a size threshold, or only a particular life stage? If identification was uncertain, record the broader group and the unresolved possibilities. A target that was not detected under a narrow rule may still have been present in a form the survey did not count. Consistent detection rules make repeated visits more interpretable and help different observers understand why they may record different outcomes.
Write a bounded conclusion
A careful entry can say “not detected in the searched area under these conditions” and then separately note any possible explanation. For example, “No nudibranchs observed on the exposed rock during a 12-minute search; lower crevices remained submerged and were not examined.” This is a useful negative observation because it describes both the result and its boundary. On a repeat visit, use a similar area and effort where possible, or flag the difference. Repeated non-detections may motivate further study, but their meaning depends on consistent methods and a clear account of where, when, and how the search took place.
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