As of September 1, 2026, your apiary is heading into autumn in generally good shape — Iris, Hive #1, and Hive #3 are all running stable, on-baseline patterns consistent with normal late-summer colony contraction, while Hive #2 remains the single hive to monitor, its 20-day acoustic decline now showing a confirmed step-change (−8.3 dBFS around August 24th) even as brood temperature stays locked at a textbook 94.7°F (34.8°C).
A striking apiary-wide contrast this period: Hive #2's sustained broad-spectrum acoustic decline (particularly the low-frequency 100–260 Hz bands, down 5–12 dB from baseline) stands in sharp relief against the perfectly stable spectral fingerprints of the other three hives, suggesting the acoustic shift is colony-specific rather than environmental — consistent with Kanelis et al. 2023 findings that queenless or disrupted colony states produce measurable step-changes in low-band acoustic energy within hours of a queen state change.
Against an outdoor swing of 64.3–86.9°F (18.0–30.5°C) at 25–57% RH with pressure steady (+0.15 hPa/3h), all four hives show clear daily vibration peaks and acoustically stable spectral fingerprints at the apiary level; in-hive humidity across all hives sits in the 41–47% range, tracking the dry late-summer ambient in a fully normal ventilation pattern with no condensation risk at current temperatures.
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Iris healthy Score: 82/100📋 Overall Health
Your Iris hive is in excellent late-summer form — the 24h average of 87.9°F (31.1°C) is 0.7°F (0.4°C) below the all-time average of 88.6°F (31.5°C), continuing the gentle four-week cooling arc (91.6→88.9→88.7→87.8°F) that is perfectly normal seasonal brood contraction heading into autumn; all 10 acoustic bands sit within ±0.4 dB of their historical baseline (a textbook-stable spectral fingerprint), humidity averaged 40.6% (consistent with the dry late-summer ambient and this hive's own norm), and vibration at 17.1 mG (kurtosis 2.5, peak 52 Hz) sits right on its all-time average of 17.3 mG. On your next routine visit, a quick check for fresh eggs will confirm the seasonal trajectory.
🌅 Diurnal Cycle PatternsA clean 4.3°F (2.4°C) daily temperature arc with all-band vibration cycles intact (14/15 days showing peaks, baseline ~16.6 mG rising to ~24.8 mG); the 200–260 Hz sound band carries the strongest daily rhythm (2.8 dB swing) and a mild shift from 200–260 Hz toward 260–350 Hz as the dominant rhythm band between the first and second halves is worth watching as a passive foraging-pattern note, but remains within normal seasonal variation; humidity is flat at ~40.6%, gas scan (100C: 67109k, 320C: 481k, 400C: 230k) sits slightly above the outdoor profile but well within this hive's own historical gas average of ~449k Ohms at 320°C, consistent with normal colony hive-air chemistry at this time of year.
🔬 Correlations & Discoveriestemperature_in vs temperature_out (14d) | r = +0.24After removing the shared diurnal cycle, in-hive temperature tracks outdoor only weakly (deconfounded r=+0.24), with outdoor leading by ~100 minutes — classic thermal-mass buffering by the colony, a sign of a healthy, well-insulated cluster actively damping ambient swings rather than passively following them.📚 Reference: Stabentheiner, Kovac & Brodschneider 2010, PLoS ONE 5(1):e8967, Fahrenholz, Lamprecht & Schricker 1989, J. Comp. Physiol. B 159:551–560▹ Action: On your next routine visit, check Iris's brood frames for fresh eggs to confirm the gentle seasonal cooling reflects normal late-summer brood contraction heading into autumn. -
Hive #2 warning Score: 58/100📋 Overall Health
Your Hive #2 brood temperature remains locked at a textbook 94.7°F (34.8°C) — a razor-tight 1.7°F (0.9°C) daily arc just 0.3°F (0.2°C) below its all-time average of 94.9°F (35.0°C) — confirming excellent thermoregulation and an active, well-populated colony; however, the acoustic decline that began around August 12th has now extended to 20 days, with a confirmed step-change of −6.99 dBFS around August 24th, bringing the overall level to −16.6 dBFS versus the all-time average of −11.3 dBFS (a −5.3 dBFS deviation), with the 100–150 Hz band down −11.8 dB and the 1500–3600 Hz band down −9.2 dB from baseline. Humidity at 47.4% is healthy and on-baseline, and vibration at 14.4 mG (kurtosis 3.1, peak 81 Hz) remains near its all-time average of 14.9 mG — the combination of rock-solid thermoregulation with a persistent, broad-spectrum acoustic step-down is the one signal worth confirming visually at your next routine visit this week.
🌅 Diurnal Cycle PatternsThe brood temperature clamping is exceptional — a compressed 1.7°F (0.9°C) daily arc at 94–95.7°F (34.5–35.4°C) — textbook stenothermy consistent with active brood incubation; all 6 vibration bands show clear daily cycles (strongest in 5–20 Hz, 6.0 dB swing, shifting toward 20–50 Hz in the second half — a passive note worth watching) with vibration peaks averaging 4.1× above the daily baseline, and the daily low-frequency acoustic rhythm in 100–150 Hz has been weakening (5.3 dB → 1.0 dB over the window), which is the most specific component of the ongoing acoustic shift; gas scan (100C: 844k, 320C: 46k, 400C: 55k) shows the characteristic flattening at high plate temperatures (resistance rising from 41k at 350°C to 55k at 400°C) that differs from the clean declining outdoor profile, consistent with this hive's historically elevated VOC load and its all-time gas average of ~50,807 Ohms at 320°C.
🔬 Correlations & Discoveriessound_energy vs temperature_in (14d) | r = +0The dissociation between a perfectly stable brood temperature and a sustained, step-changed acoustic decline is the most informative pattern here — thermoregulation requires only that enough bees are present and active, while the acoustic spectral shape (particularly the weakening low-frequency 100–260 Hz daily rhythm) encodes colony state information independent of thermal output; Kanelis et al. 2023 document that queen-state changes produce measurable low-band acoustic step-changes within hours, making a visual queen/brood check the natural next step.📚 Reference: Kanelis et al. 2023, Biology 12(11):1392, Ramsey, Bencsik, Newton et al. 2020, Sci. Rep. 10:9798temperature_in vs humidity_in (14d) | r = +0.65The genuine (deconfounded) r=+0.65 between in-hive temperature and humidity — even after removing the shared diurnal cycle — reflects active hygroregulation coupled to brood heating: as the colony warms the brood core, water vapour from larval respiration and honey processing rises in step, a healthy sign of an actively regulated brood nest (Human et al. 2006).📚 Reference: Human, Nicolson & Dietemann 2006, Naturwissenschaften 93:397–401, Ellis et al. 2008, J. Insect Physiol. 54:1516–1521⚠️ Issue: Sustained 20-day multi-band acoustic decline with confirmed step-change of −6.99 dBFS around August 24th: overall sound at −16.6 dBFS vs all-time average of −11.3 dBFS; 100–150 Hz band −11.8 dB below baseline, 1500–3600 Hz band −9.2 dB below baseline; daily low-frequency rhythm weakening (100–150 Hz: 5.3→1.0 dB); brood temperature, vibration, humidity, and gas all remain on-baseline — single acoustic-channel anomaly, no corroborating colony-distress signals.▹ Action: On your next routine visit this week, observe Hive #2's entrance for forager traffic and pollen-carrying activity, and check brood frames for fresh eggs and queen presence — the 20-day acoustic step-down is the one signal worth confirming visually, even though the rock-solid thermoregulation is reassuring. -
Hive #1 warning Score: 74/100📋 Overall Health
Your Hive #1 continues its gradual but acoustically-confirmed-benign cooling drift — the 24h average of 83.3°F (28.5°C) is now 1.7°F (0.9°C) below the all-time average of 85.0°F (29.4°C), extending the steady 14-day cooling trend (85.8→86.2→84.7→83.3°F weekly); crucially, all 10 acoustic bands remain within ±0.2 dB of their all-time baseline — a near-perfect spectral match that confirms the full worker population is intact, pointing clearly to a natural late-summer broodless or reduced-brood period as the most likely explanation for the temperature decline. Humidity at 43.0% and vibration at 16.4 mG (kurtosis 2.7, peak 75 Hz) both sit right on their all-time averages — on your next routine visit, a check for fresh eggs will clarify whether this reflects a natural seasonal brood contraction or a brief laying pause.
🌅 Diurnal Cycle PatternsA healthy 6.2°F (3.4°C) daily temperature arc (81.2–86.3°F / 27.3–30.2°C) with clear daily vibration cycles (15/15 days, baseline ~15.8 mG rising to ~22.9 mG peaks); the gas heater-scan shows the strongest per-band daily rhythm across all 10 steps (max 35% swing at 100°C), which is the dominant pattern here and reflects the colony's normal daily ventilation cycle circulating hive volatiles — the 14-day gas-humidity coupling (deconfounded r=+0.47) and a very strong partial correlation of gas resistance with in-hive temperature controlling for outdoor weather (r=−0.85) point to temperature-driven VOC volatilisation as the primary driver of gas variation, a benign metabolic signature; no strong per-band acoustic daily rhythm (max 0.6 dB) and vibration dominant rhythm shifting from 5–20 Hz to 80–120 Hz in the second half are passive notes consistent with normal seasonal activity changes.
🔬 Correlations & Discoveriesgas_resistance vs temperature_in (14d) | r = -0.85The very strong partial correlation between gas resistance and in-hive temperature (r=−0.85, controlling for outdoor weather) reflects temperature-driven volatilisation of hive VOCs — as the brood zone warms, propolis terpenes, brood pheromones (E-β-ocimene), and honey processing esters become more volatile, lowering MOX resistance; this is a healthy metabolic signature of an active colony, not a stress signal.📚 Reference: Burgues & Marco 2018, Sensors 18(2):339, Maisonnasse et al. 2010, PLoS ONE 5(10):e13531⚠️ Issue: Gradual 14-day cooling drift: 24h average 83.3°F (28.5°C), continuing a 2.5°F (1.4°C) decline over four weekly averages; acoustic spectrum is perfectly stable (all bands within ±0.2 dB of baseline), confirming an intact population — most likely a natural late-summer brood contraction or laying pause.▹ Action: On your next routine visit, check Hive #1's brood frames for fresh eggs and brood pattern to confirm the gradual cooling drift reflects a natural late-summer brood contraction — the acoustically intact population is reassuring and there is no urgency. -
Hive #3 healthy Score: 80/100📋 Overall Health
Your Hive #3 continues its excellent run — the 24h average of 92.0°F (33.3°C) sits just 0.6°F (0.3°C) below the all-time average of 92.6°F (33.7°C), well within the normal brood band and continuing a gentle, entirely normal seasonal tail-off (93.4→93.2→92.5→91.9°F weekly); all 10 acoustic bands are within ±0.2 dB of their historical baseline — a textbook-stable fingerprint — with humidity at 46.2% (healthy and on-baseline for this hive) and vibration at 20.6 mG (kurtosis 3.2, peak 37 Hz) sitting right on its all-time average of 20.8 mG. The battery touched its all-time low of 3,982 mV within the 24h window and is currently at 4,012 mV — worth monitoring passively as solar input decreases heading into autumn.
🌅 Diurnal Cycle PatternsA tight 2.8°F (1.6°C) daily temperature arc (90.4–93.1°F / 32.4–34.0°C) with strong all-band vibration cycles (15/15 days, baseline ~19.4 mG rising to ~34.9 mG peaks); vibration dominant rhythm shifting from 5–20 Hz to 80–120 Hz in the second half mirrors Hive #1's pattern — a passive seasonal note consistent with late-summer fanning activity gradually transitioning from ventilation-dominated to foraging-dominated rhythms; the gas heater-scan (100C: 2840k, 320C: 89k, 400C: 93k) shows a characteristic slight uptick at 375–400°C relative to 350°C, consistent with this hive's own elevated VOC baseline (all-time gas average 92,668 Ohms at 320°C vs outdoor 747k Ohms), likely reflecting active honey ripening or propolis work; humidity averages 46.2%, flat and healthy.
🔬 Correlations & Discoveriestemperature_in vs gas_resistance (14d) | r = +0.51The genuine deconfounded r=+0.51 between in-hive temperature and gas resistance (after removing the shared diurnal cycle) reflects the temperature-dependent volatilisation of propolis terpenes and brood pheromones — warmer colony core temperatures drive more VOC off-gassing, a normal and healthy metabolic signature of an active brood nest (Bankova et al. 2000; Maisonnasse et al. 2010).📚 Reference: Maisonnasse et al. 2010, PLoS ONE 5(10):e13531, Bankova et al. 2000, Apidologie 31:3–15▹ Action: Monitor Hive #3's battery passively — it touched its all-time low of 3,982 mV within the last 24 hours (currently 4,012 mV); no action needed yet, but keep an eye on the trend as solar input decreases heading into autumn.▹ Action: On your next routine visit, note capping progress on Hive #3's supers — the stable acoustic and gas fingerprints suggest honey processing is active and a capped-frame count will help plan your late-summer harvest timing.