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iNotes
iTag Explorer was created by Peter Jennings (and claude.ai) to play with the data recorded by a Hydromoth monitoring the sounds in the bay. This is not a scientific study. Monitoring was on for 600 hours over the summer in discontinuous sessions. Trigger level and other parameters were not held constant.
For complete information on how to use this tool, please read the User Manual.
The Innovasea tags nominally transmit 8 to 10 pulses, resulting in 7 to 9 timed intervals which encode the ID. Shorter IDs are the result of noise, signal collisions, and the ageing of tags with dying batteries. Some tags transmit sensor data which this analysis interprets as a different tag.
This tool and the data are updated often. It is recommended you refresh the page with ctrl-shift held to ensure you see the latest information.
Methodology
Sunrise and sunset are computed for the monitoring site's coordinates using the standard NOAA solar position equations (Julian day → solar mean anomaly → ecliptic longitude → declination → hour angle), with the horizon taken at −0.833° to allow for refraction and the sun's radius. They are recalculated for each calendar date, so seasonal changes in day length are accounted for. These drive the day/night shading behind the Signal Strength plot.
Dawn and dusk are each taken as the 90 minute window centred on sunrise and sunset respectively — 45 minutes either side. Day is the span between the end of dawn and the start of dusk; night is everything outside. Matutinal ranks by the share of detections at dawn, Vespertine by the share at dusk, and Crepuscular by the two combined.
Nocturnal and Diurnal use a simpler two‑way split at true sunrise and sunset, without the twilight windows, so the two percentages are complementary and sum to 100%.
Full Moon and New Moon split each detection by lunar illumination, computed from a standard synodic‑month approximation (29.530589 days) anchored to a known new moon, independent of site coordinates. Full Moon is the share of detections falling when the moon is more than half illuminated; New Moon is the complementary share when it's less than half illuminated — the two percentages sum to 100%. Waxing and Waning instead split on which half of the cycle the detection fell in — the two weeks after new moon (brightening) versus the two weeks after full moon (dimming) — and are likewise complementary.
Cathemeral measures the absence of any timing preference rather than a share of one period, so it is scored as the normalised Shannon entropy of each ID's hourly distribution: H = −∑p ln p over the 24 hourly bins, divided by ln 24. 100% means activity spread perfectly evenly across every hour; 0% means every detection fell in a single hour.
Speed is |change in signal| divided by the minutes between two successive detections of the same ID, reported in m/s after dividing by 100. Pairs more than 30 minutes apart, or with a zero reading at either end, are ignored. Each pair is attributed to the hour its first detection falls in, and a cell reports the maximum of the pairs starting in that hour.
Temperature readings are matched to each detection by nearest timestamp, restricted to dates that have at least one detection, then binned to the nearest 0.5° (that is, ±0.25°).
Species probability is a heuristic behavioural classifier, not a measured identification. Each tag's timing signature is scored against three species' known chronobiology, and the three scores are normalised so they sum to 100%. The weights are hand‑tuned to reflect published behaviour rather than fitted to this data, so treat the result as a prior, not evidence. A tag with no measurable speed is given a neutral speed factor so it isn't unfairly penalised.
Reasoning used for each species' signature:
Smallmouth vs. largemouth is a secondary split shown in the single‑ID panel only when Bass is already that ID's top species guess — it's not a fourth species in its own right, just a further breakdown of "which kind of Bass". Smallmouth are more active, roaming chase‑feeders that stay busy through daylight (rewards Diurnal % and higher Max Speed); largemouth are slower, more sedentary ambush predators that lean nocturnal, especially in warm water (rewards Nocturnal % and lower Max Speed). The two percentages always sum to 100%.