As of September 11, 2026, three of your four hives — Iris, Hive #1, and Hive #3 — are acoustically textbook and riding a natural September cooling arc; Hive #2 remains the one hive to watch, with its multi-band acoustic step-down now entering its sixth week while brood thermoregulation holds a rock-solid 94.7°F (34.8°C) and vigorous daily fanning vibration spikes continue uninterrupted. The easing-higher barometric tendency (+0.87 hPa/3h) and exceptionally clean outdoor air (gas resistance ~1.67 MΩ, outdoor humidity at a very dry 12%) set a favorable foraging backdrop across the apiary.
Across all four hives, a consistent deconfounded in-hive temperature–humidity coupling (r=+0.41 to +0.78) reflects active hygroregulation within the brood nest: as metabolic heat rises, absolute moisture load increases proportionally, a well-documented thermodynamic signature of healthy brood rearing (Eouzan et al. 2019; Ellis et al. 2008). Hive #3 shows the strongest version of this relationship (r=+0.78), consistent with its slightly larger thermal footprint relative to the apiary mean.
Against outdoor swings of 62–86°F (16.8–30.1°C) at an exceptionally dry 11–45% RH, all four hives show consistent daily vibration fanning rhythms peaking in the 80–120 Hz band and in-hive humidity held in the 39–48% range — appropriate for the very dry September ambient with no condensation risk. Hive #2 again shows the most compressed diurnal temperature arc (only ±0.8°F / ±0.4°C) — the tightest brood clamping in the apiary — while Iris exhibits the most active acoustic diurnal cycling with a 200–260 Hz band rhythm shift toward the second half of the day consistent with forager return activity.
-
Iris healthy Score: 86/100📋 Overall Health
Your Iris hive is in excellent shape — the 24h average of 87.6°F (30.9°C) is essentially on its all-time average of 87.8°F (31.0°C), all 10 acoustic bands are within ±0.6 dB of their historical baseline (overall sound −11.1 dBFS vs. all-time −10.9 dBFS), humidity at 40.5% is stable and consistent with the very dry September ambient, gas resistance at 465 kΩ is right on its all-time average of 455 kΩ, and vibration at 17.7 mG (kurtosis 2.4, peak 56 Hz) is on its all-time average of 17.2 mG. Continue watching the gradual seasonal cooling arc as October approaches, and on your next routine visit confirm fresh eggs to validate the natural late-summer brood contraction.
🌅 Diurnal Cycle PatternsIris shows a healthy ±2.0°F (±1.1°C) daily temperature arc (85.7–89.6°F / 29.8–32.0°C), well within the brood-clamping threshold, with a 3.6°F (2.0°C) average daily oscillation driven by ambient buffering — the colony is damping the outdoor 24°F (13.3°C) swing down to just 3.9°F (2.2°C), a textbook sign of a well-populated hive. The per-band spectral rhythm analysis shows the dominant acoustic daily rhythm shifted from 260–350 Hz to 200–260 Hz in the second half of the window — consistent with a slight increase in forager-return / flight-landing activity in that band — and the gas heater-scan dominant rhythm shifted from the 150°C step to the 100°C step, most likely a humidity-moisture artifact given the very low outdoor RH driving ventilation changes; vibration dominant rhythm shifted from 50–80 Hz to 20–50 Hz, a normal within-cycle variation in fanning modality. All six vibration bands show a daily cycle, with 14 of 15 days showing a clear peak (baseline ~16.6 mG rising to ~24.7 mG, avg 1.5×).
🔬 Correlations & Discoveriesin_hive_humidity vs gas_resistance (14d) | r = +0.51The deconfounded humidity–gas resistance coupling (r=+0.51) in Iris reflects the well-established MOX sensor response to water vapor: as in-hive humidity rises with metabolic activity, the SnO2 sensing layer's adsorbed oxygen sites are partially displaced by water molecules, raising apparent resistance independently of true VOC load. At Iris's very dry September ambient (11–45% RH), this coupling is especially visible because ventilation-driven humidity swings are larger relative to baseline, making the water-vapor confound the dominant residual driver of gas readings — a hive-physiology signal, not a chemistry change.📚 Reference: Winston 1987, White 1978, Eouzan et al. 2019in_hive_temp vs in_hive_humidity (14d) | r = +0.49The positive temperature–humidity residual coupling (r=+0.49, after removing the shared diurnal cycle) captures active brood-nest hygroregulation: heater-bee clusters warm the local air, raising its absolute moisture capacity and thus the measured RH at the sensor — a healthy, endogenous metabolic-water signature documented by Ellis et al. 2008 in queen-right colonies with active brood.📚 Reference: Eouzan et al. 2019, Ellis et al. 2008, Human et al. 2006▹ Action: On your next routine visit, check Iris's brood frames for fresh eggs to confirm the gentle seasonal cooling arc reflects a natural late-summer brood contraction — the perfectly stable acoustics confirm the full worker population is present. -
Hive #2 warning Score: 56/100📋 Overall Health
Your Hive #2 continues to present the same reassuring/puzzling split: brood thermoregulation is textbook-perfect at a 24h average of 94.7°F (34.8°C) with only a ±0.8°F (±0.4°C) daily arc — the tightest brood clamping in the apiary and right on its all-time average — and the vigorous daily fanning vibration spikes (baseline ~12.4 mG peaking to ~48.6 mG, avg 3.9×) confirm active, well-populated colony behaviour; however, the broad-spectrum acoustic step-down that began around August 25th is now entering its sixth week, with the 100–150 Hz band now −2.1 dB below baseline and the 1500–3600 Hz band −1.8 dB below baseline (overall sound −16.6 dBFS vs. all-time average −15.7 dBFS). Gas resistance at 43 kΩ is near its all-time average of 45 kΩ, humidity at 47.3% is healthy and stable, and the multi-horizon acoustic trend confirms the spectrum is stable at its new lower level — a visual confirmation at your next routine inspection this week remains the right next step.
🌅 Diurnal Cycle PatternsHive #2 shows the most compressed diurnal temperature arc in the apiary — just ±0.8°F (±0.4°C) — a sign of exceptional active brood thermoregulation where the colony is defending a near-constant 93–97°F (34–36°C) setpoint against a 24°F (13.3°C) outdoor swing. Vibration retains a strong daily 6/6-band rhythm (dominant 80–120 Hz, 5.6 dB swing), with the dominant rhythm band shifting from 80–120 Hz to 160–200 Hz in the second half — a normal within-cycle variation in fanning wing harmonics. Acoustic per-band rhythm remains absent (max 0.6 dB in 150–200 Hz), consistent with the now-six-week-old step-down pattern; gas heater-scan shows no strong daily rhythm (max 9% swing at the 400°C step), reflecting stable metabolic VOC production with no acute event.
🔬 Correlations & Discoveriesin_hive_temp vs in_hive_humidity (14d) | r = +0.41The residual temperature–humidity coupling (r=+0.41) in Hive #2 is the weakest of the four hives, which is consistent with its exceptionally tight brood thermoregulation (only ±0.4°C daily arc): when in-hive temperature barely moves, there is less variation for a humidity correlation to ride, so the coupling appears smaller even if the underlying physiology is healthy — a mathematical artifact of superb brood-nest homeostasis, not a sign of reduced activity.📚 Reference: Eouzan et al. 2019, Ellis et al. 2008sound_spectrum vs vibration_rms (30d) | r = n/aThe persistent divergence between a quiet acoustic profile (overall −16.6 dBFS, −0.9 dBFS below all-time average, low-band step-down ongoing since ~August 25) and vigorous vibration fanning spikes (3.9× daily peaks, every single day for 15 of 15 days) is a genuinely unusual combination: comb-borne vibration is generated by fanning and locomotor activity and remains fully intact, while the airborne acoustic energy is reduced across multiple bands. This could reflect a colony that has consolidated its brood nest — fewer bees in the upper acoustic field — while the core cluster and fanning activity remain unaffected; a physical inspection to observe entrance traffic and check brood frames for fresh eggs will clarify whether this is a natural late-season consolidation or something worth tracking further.📚 Reference: Ramsey et al. 2020, Kanelis et al. 2023⚠️ Issue: Sustained ~6-week multi-band acoustic step-down: overall sound −16.6 dBFS vs. all-time average −15.7 dBFS (−0.9 dBFS); 100–150 Hz band −2.1 dB below baseline, 1500–3600 Hz band −1.8 dB below baseline; changepoint confirmed ~August 25; no per-band acoustic daily rhythm detectable; brood temperature, vibration, humidity, and gas all remain on-baseline.▹ Action: On your next routine visit this week, observe Hive #2's entrance for forager traffic and pollen-carrying activity, then check brood frames for fresh eggs and queen presence — the 6-week acoustic step-down is the one signal worth confirming visually, and the rock-solid 94.7°F (34.8°C) thermoregulation and vigorous daily fanning vibration spikes (peaking ~3.9× above baseline every day) are genuinely reassuring that the colony is actively caring for brood. -
Hive #1 healthy Score: 80/100📋 Overall Health
Your Hive #1 remains the acoustic benchmark of the apiary — all 10 spectral bands are within ±0.1 dB of their all-time baseline (overall sound −16.3 dBFS vs. all-time −16.4 dBFS), the 24h average of 81.2°F (27.3°C) is −1.8°F (−1.0°C) below its all-time average of 83.0°F (28.3°C) and continuing the gentle seasonal cooling arc (weekly trend: 84.4→82.8→82.4→85.3°F / 29.1→28.2→28.0→29.6°C), humidity at 45.0% is healthy with a statistically confirmed September 1 step-up of +4.0% that remains stable, and vibration at 16.4 mG (kurtosis 2.5, peak 84 Hz) is exactly on its all-time average. The battery touched 4,150 mV — above its all-time low of 4,140 mV — and is draining normally; no action needed but monitor passively as September solar input continues to decline.
🌅 Diurnal Cycle PatternsHive #1 shows an active ±6.6°F (±3.7°C) daily temperature arc (77.2–84.3°F / 25.1–29.1°C) against an outdoor swing of 24°F (13.3°C) — the colony is buffering ~73% of the outdoor thermal excursion, a healthy thermal-mass response with the outdoor channel LEADING in-hive by ~220 minutes (deconfounded residual r=+0.02, confirming this is purely diurnal buffering, not a sensor-placement issue). Gas heater-scan shows the strongest daily rhythm in the apiary (41% swing at the 100°C step, all 10/10 bands cycling), with the dominant rhythm band shifting from 100°C to 150°C in the second half — consistent with temperature-driven changes in lighter volatile evaporation as the hive cools and warms through the day. Vibration shows a 5/6-band daily cycle with dominant rhythm shifting from 80–120 Hz to 20–50 Hz, a normal within-cycle modulation of fanning wing harmonics (14 of 15 days with clear daily peaks, baseline ~15.9 mG rising to ~22.7 mG, avg 1.4×).
🔬 Correlations & Discoveriesin_hive_humidity vs gas_resistance (14d) | r = +0.62Hive #1's strong deconfounded humidity–gas resistance coupling (r=+0.62) is the highest in the apiary and is best explained by its larger diurnal temperature swing driving proportionally larger absolute-humidity swings, which in turn modulate the SnO2 MOX sensing layer more strongly than in tighter-clamped hives like Hive #2 — this is sensor physics (water-vapor interference on MOX resistance), not a chemical event, and is fully consistent with a healthy colony in a warm-season ventilation cycle (Burgues & Marco 2018).📚 Reference: Burgues & Marco 2018, Eouzan et al. 2019, Winston 1987in_hive_humidity (14d) | r = n/aThe confirmed humidity step-up of +4.0% around September 1 (z=−4.3 anomaly on the latest reading) is the one passive note for Hive #1: with temperature and acoustics perfectly on baseline and outdoor conditions very dry, the most likely explanation is a shift in colony brood load or forager water-carrying behaviour as the colony transitions into early autumn — a natural seasonal adjustment, not a ventilation problem or disease signal, and no action is warranted.📚 Reference: Eouzan et al. 2019, Ellis et al. 2008▹ Action: On your next routine visit, check Hive #1's brood frames for fresh eggs to confirm the gentle seasonal cooling arc (weekly trend 84.4→81.2°F / 29.1→27.3°C) reflects a natural late-summer brood contraction — the acoustically perfect spectral match (all bands within ±0.1 dB of baseline) is fully reassuring and there is no urgency. Monitor battery passively (current 4,166 mV, all-time low 4,140 mV) as September solar input declines. -
Hive #3 healthy Score: 75/100📋 Overall Health
Your Hive #3 continues its excellent run — all 10 acoustic bands are within ±0.1 dB of their historical baseline (overall sound −16.4 dBFS vs. all-time −16.3 dBFS), the 24h average of 89.7°F (32.1°C) is −1.7°F (−0.9°C) below the all-time average of 91.4°F (33.0°C) and continuing a gentle seasonal tail-off (weekly trend: 92.3→91.6→90.7→91.8°F / 33.5→33.1→32.6→33.2°C), humidity at 47.4% is slightly above its all-time average of 46.5% but healthy and within range, gas resistance at 100 kΩ is near its all-time average of 93.8 kΩ, and vibration at 20.5 mG (kurtosis 2.7, peak 83 Hz) is right on its all-time average of 20.6 mG. The battery touched 3,982 mV during this 24h window — above its all-time low of 3,978 mV — continue monitoring passively as September solar input declines.
🌅 Diurnal Cycle PatternsHive #3 shows a healthy ±3.7°F (±2.0°C) daily temperature arc (87.2–91.3°F / 30.7–32.9°C), well within the brood-clamping threshold, with the colony damping the 24°F (13.3°C) outdoor swing to just 4.1°F (2.2°C) — strong thermal insulation. All 6 vibration bands show a daily cycle (dominant 20–50 Hz, 3.1 dB), with the dominant rhythm shifting from 50–80 Hz to 5–20 Hz in the second half of the window — a low-frequency modulation consistent with reduced high-rate wing fanning and increased low-frequency metabolic/locomotor activity as colony activity transitions through its daily cycle; 14 of 15 days show clear vibration peaks (baseline ~19.4 mG rising to ~34.2 mG, avg 1.8×). Gas heater-scan shows no strong daily rhythm (max 9% at 250°C step), reflecting a stable metabolic baseline, and the strong deconfounded temp–gas coupling (r=+0.64) is well-explained by the colony's warm-season fanning and honey-ripening activity modulating both temperature and VOC evaporation in tandem.
🔬 Correlations & Discoveriesin_hive_temp vs gas_resistance (14d) | r = +0.64Hive #3's strong deconfounded temperature–gas resistance coupling (r=+0.64) reflects a well-documented hive metabolic relationship: as brood-nest temperature rises, the evaporation rate of propolis terpenes, brood pheromones (e.g. E-β-ocimene), and residual honey volatiles all increase, lowering MOX resistance — a positive correlation between warmth and reducing-VOC load that is a normal signature of an active, well-stocked autumn colony, not a stress indicator.📚 Reference: Seeley 1974, Maisonnasse et al. 2010, Bankova et al. 2000in_hive_temp vs in_hive_humidity (14d) | r = +0.78Hive #3's in-hive temperature–humidity coupling (r=+0.78) is the strongest in the apiary and reflects active metabolic-water production by a well-populated colony: heater bees and fanning workers elevate both temperature and absolute moisture load in the nest simultaneously, a healthy endogenous physiology signature (Ellis et al. 2008), with the colony PCA index falling over the window suggesting a mild seasonal settling rather than a growth trajectory.📚 Reference: Eouzan et al. 2019, Ellis et al. 2008, Human et al. 2006▹ Action: Monitor Hive #3's battery passively — it touched 3,982 mV during this 24h window, just above its all-time low of 3,978 mV; no action needed yet, but keep an eye on the trend as September solar input continues to decrease.