As of September 13, 2026, your apiary is in good overall shape heading into mid-September — Iris, Hive #1, and Hive #3 are all acoustically stable and on or near their historical baselines, while Hive #2 continues the same reassuring split it has shown for eight weeks: textbook brood thermoregulation at 94.8°F (34.9°C) with vigorous daily fanning spikes, but a persistent multi-band acoustic step-down that warrants a visual check. The rising barometric tendency (+1.31 hPa/3h) and exceptionally clean outdoor air (gas resistance ~1.25 MΩ, outdoor humidity 17–37%) continue to provide a favorable foraging backdrop.
All four hives show a strong deconfounded temp–humidity coupling (r=+0.57 to +0.87) that persists after removing the shared diurnal cycle — reflecting active brood-nest hygroregulation independent of the very dry September ambient (outdoor 17–37% RH), exactly as documented by Eouzan et al. 2019 and Human et al. 2006.
All four hives maintain consistent daily vibration fanning rhythms dominated by the 80–120 Hz band, with in-hive humidity held in the 38–47% range — appropriate given the very dry September ambient. Hive #2 remains the most tightly clamped thermally (±1.1°F / ±0.6°C daily arc), Hive #3 sits at ±1.6°F (±0.9°C), Iris at ±3.3°F (±1.8°C), and Hive #1 shows the widest swing at ±7.9°F (±4.4°C) — all within normal September parameters for their respective placements.
-
Iris healthy Score: 87/100📋 Overall Health
Your Iris hive continues in excellent shape — the 24h average of 88.9°F (31.6°C) is +1.1°F (+0.6°C) above its all-time average of 87.8°F (31.0°C), sitting within the gentle warming drift (+2.3°F / +1.3°C) observed over the past 14 days, all 10 acoustic bands are within ±0.3 dB of their historical baseline (overall −11.0 dBFS matching the all-time −10.9 dBFS), humidity at 38.6% is stable and consistent with the dry September ambient, gas resistance at 469 kΩ is right on its all-time average of 459 kΩ, and vibration at 17.9 mG (kurtosis 2.6, peak 83 Hz) is on its all-time average. Watch for the gentle warming arc to plateau as September progresses — a routine brood-frame check on your next visit remains the right cadence.
🌅 Diurnal Cycle PatternsIris shows a healthy ±3.3°F (±1.8°C) daily temperature arc (range 87.3–90.6°F / 30.7–32.5°C), with a clear thermal rise phase and the 200–260 Hz acoustic band carrying the strongest per-band daily rhythm (2.6 dB swing) — consistent with foraging-correlated activity. Vibration shows a daily fanning rhythm across all 6 bands (dominant 80–120 Hz at −9.7 dB avg), with a noted rhythm-band shift from 50–80 Hz to 5–20 Hz between the first and second half of the window; this low-frequency drift is consistent with a natural DVAV circadian signature (Fletcher 1975; Ramsey et al. 2018) and is not an anomaly. The gas heater-scan shows a modest daily rhythm (strongest at 150°C, +14% swing), with the dominant rhythm step shifting from 150°C to 5–20 Hz in the second half — reflecting normal metabolic-water and fanning-ventilation cycling through the colony's day/night respiration rhythm.
🔬 Correlations & Discoveriestemperature_in vs humidity_in (14d) | r = +0.57The genuine deconfounded temp–humidity coupling (r=+0.57) on Iris reflects active brood-nest hygroregulation: as internal temperature rises with metabolic activity, absolute moisture content climbs, keeping RH relatively stable despite the very dry outdoor ambient (~17–37% RH). This is a healthy colony maintaining its microclimate independent of outside conditions — textbook homeostasis.📚 Reference: Eouzan et al. 2019 (PLOS ONE / PMC6368279), Human, Nicolson & Dietemann 2006humidity_in vs gas_resistance (14d) | r = +0.51The humidity–gas resistance coupling (r=+0.51) on Iris reflects the well-established MOX humidity-confounding effect: higher in-hive moisture slightly depresses the SnO2 baseline, producing a correlated movement that tracks colony metabolic water production and fanning cycles rather than any VOC event — consistent with active honey ripening and brood-pheromone cycling in a healthy September colony.📚 Reference: Winston 1987, Seeley 1974▹ Action: On your next routine visit, check Iris's brood frames for fresh eggs to validate the gentle 14-day warming drift (+2.3°F / +1.3°C) — the perfectly stable acoustic spectrum and on-baseline vibration confirm the full worker population is present and active. -
Hive #2 warning Score: 62/100📋 Overall Health
Your Hive #2 presents the same reassuring/puzzling split entering its eighth week: brood thermoregulation remains textbook at a 24h average of 94.8°F (34.9°C) with a compressed ±1.1°F (±0.6°C) daily arc — exactly on its all-time average and the tightest brood clamping in the apiary — and vigorous daily fanning vibration spikes (baseline ~12.4 mG peaking to ~48.9 mG, avg 3.9×) confirm active, well-populated colony behaviour. However, the broad-spectrum acoustic step-down that began around August 25 is now in its eighth week: the 100–150 Hz band sits −0.5 dB below its all-time baseline and the 800–1500 Hz and 1500–3600 Hz bands are each −0.4 dB below baseline (overall −16.6 dBFS vs. all-time −16.4 dBFS); the rock-solid thermoregulation and daily fanning spikes are genuinely reassuring, but a visual entrance and brood check this week remains the right next step.
🌅 Diurnal Cycle PatternsHive #2's temperature arc is the tightest in the apiary at ±1.1°F (±0.6°C) — a sign of dense, active brood heating. Vibration shows the strongest daily rhythm across all 6 bands (dominant shift from 20–50 Hz to 80–120 Hz between window halves, with 120–160 Hz strengthening from 5.0 to 8.2 dB and 50–80 Hz from 5.1 to 8.1 dB) — consistent with intensifying fanning activity in the second half of the monitoring window, likely driven by honey ripening or thermoregulation in the September heat. The gas heater-scan shows no strong per-band daily rhythm (max +9% at 300°C step), with the dominant rhythm step shifting from 150°C to 300°C — a mid-temperature-step shift suggesting a gradual change in the predominant VOC class being sensed, most plausibly reflecting seasonal propolis curing or late-summer honey ripening activity rather than any acute event.
🔬 Correlations & Discoveriestemperature_in vs gas_resistance (14d) | r = +0.83The strong deconfounded temp–gas coupling (r=+0.83) on Hive #2 reflects the colony's own metabolic state: as brood-nest temperature rises with active heating, internal VOC production (brood pheromones, wax metabolism, fanning-circulated honey volatiles) co-rises, reducing MOX resistance in lockstep — a healthy metabolic signature of intense brood rearing, not a stress indicator.📚 Reference: Seeley 1985, Stalidzans et al. 2017temperature_in vs humidity_in (14d) | r = +0.83The equally strong temp–humidity coupling (r=+0.83, partial r=+0.55 controlling for outdoor weather) confirms that Hive #2's hygroregulation is genuinely colony-driven and independent of outdoor conditions — the colony is actively managing both heat and moisture in its brood nest, consistent with dense brood and high nurse-bee activity.📚 Reference: Human, Nicolson & Dietemann 2006, Eouzan et al. 2019 (PLOS ONE / PMC6368279)⚠️ Issue: Sustained ~8-week multi-band acoustic step-down: overall sound −16.6 dBFS vs. all-time average −16.4 dBFS; 100–150 Hz band −0.5 dB below baseline, 800–1500 Hz and 1500–3600 Hz bands each −0.4 dB below baseline; changepoint confirmed ~August 25; no strong per-band acoustic daily rhythm detectable — all other channels (brood temp, vibration, humidity, gas) 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 8-week acoustic step-down remains the one signal worth confirming visually, and the rock-solid 94.8°F (34.9°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: 78/100📋 Overall Health
Your Hive #1 remains acoustically textbook — all 10 spectral bands are within ±0.2 dB of their all-time baseline (overall −16.4 dBFS matching the all-time −16.4 dBFS exactly), the 24h average of 83.8°F (28.8°C) is +1.2°F (+0.7°C) above its all-time average of 82.6°F (28.1°C) and continuing a stable September plateau (weekly trend: 84.0→82.8→82.4→81.7°F / 28.9→28.2→28.0→27.6°C), humidity at 42.7% sits just below the September 1 step-change level of ~45% following a confirmed −2.6% changepoint around September 11, vibration at 16.4 mG (kurtosis 2.6, peak 91 Hz) is exactly on its all-time average, and the battery at 4,186 mV is comfortably healthy. The humidity step-down around September 11 is the most plausible explanation for the dry-air trend intensifying as September progresses — watch passively on your next visit.
🌅 Diurnal Cycle PatternsHive #1 shows the widest daily temperature arc in the apiary at ±7.9°F (±4.4°C) (range 79.7–87.6°F / 26.5–30.9°C), which is its established September rhythm — the deconfounded analytics confirm this is purely diurnal buffering (raw r=+0.44, deconfounded r=−0.02 vs. outdoor temp) and not a population or placement issue. Vibration shows all 6 bands cycling daily (dominant 5–20 Hz rhythm at 3.0 dB), consistent with normal foraging and fanning schedules. The gas heater-scan shows the strongest per-band daily rhythm in the apiary (100°C step +41% swing, all 10 steps cycling), with the dominant rhythm step shifting from 100°C to 150°C in the second half — the very strong low-temperature-step cycling reflects the high humidity sensitivity of the 100–150°C MOX range, coupling to the in-hive moisture cycle; the confirmed humidity changepoint (−2.6% around September 11) likely accounts for the shift toward the 150°C dominant step as the moisture fingerprint changes.
🔬 Correlations & Discoveriestemperature_in vs humidity_in (14d) | r = +0.85The strongest temp–humidity coupling in the apiary (r=+0.85, partial r=+0.36 controlling for outdoor weather) on Hive #1 reflects robust colony hygroregulation: the confirmed −2.6% humidity step-change around September 11 tracks the intensifying dry ambient (outdoor 17–37% RH) ventilating through the hive, while the colony maintains its internal moisture-temperature balance — a natural response to the September drying trend, not a colony fault.📚 Reference: Eouzan et al. 2019 (PLOS ONE / PMC6368279), Human, Nicolson & Dietemann 2006humidity_in vs gas_resistance (14d) | r = +0.68The humidity–gas coupling (r=+0.68, partial gas–temp controlling for outdoor r=−0.67) on Hive #1 reveals an interesting sign reversal: while higher humidity generally lifts MOX resistance via water-vapor site blocking, the negative partial correlation when controlling for outdoor temperature suggests the gas signal is also driven by colony-specific VOC production (brood pheromones, propolis) that rises independently of humidity — a hive with active late-summer metabolic cycling.📚 Reference: Burgues & Marco 2018, Sensors 18(2):339, Winston 1987▹ Action: On your next routine visit, confirm fresh eggs on Hive #1's brood frames to validate the gradual seasonal cooling arc (weekly trend 84.0→81.7°F / 28.9→27.6°C over 14 days) — the acoustically perfect spectral match and on-baseline vibration are fully reassuring. Monitor the humidity passively following the September 11 step-down (−2.6%) and the battery passively (current 4,186 mV, all-time low 4,130 mV). -
Hive #3 healthy Score: 79/100📋 Overall Health
Your Hive #3 continues its excellent run — all 10 acoustic bands are within ±0.1 dB of their historical baseline (overall −16.3 dBFS matching the all-time −16.3 dBFS exactly), the 24h average of 90.5°F (32.5°C) is −0.6°F (−0.3°C) below the all-time average of 91.1°F (32.8°C) and continuing a gentle seasonal cooling arc (weekly trend: 92.1→91.6→90.7→89.8°F / 33.4→33.1→32.6→32.1°C), humidity at 46.2% is right on its all-time average of 46.4%, gas resistance at 94 kΩ is exactly on its all-time average of 94 kΩ, and vibration at 20.7 mG (kurtosis 2.9, peak 61 Hz) is on its all-time average of 20.6 mG. The battery touched 3,980 mV — just above its all-time low of 3,978 mV — worth passive monitoring as September solar input continues to decline.
🌅 Diurnal Cycle PatternsHive #3 shows a well-regulated ±1.6°F (±0.9°C) daily temperature arc (range 88.6–91.8°F / 31.5–33.2°C), sitting just below but approaching the ideal 93–97°F (34–36°C) brood band as the seasonal cooling arc progresses. Vibration shows all 6 bands cycling daily (strongest at 50–80 Hz, 3.6 dB rhythm), with a dominant rhythm-band shift from 50–80 Hz to 5–20 Hz in the second half — a pattern seen on Iris as well, consistent with a natural DVAV circadian rhythm shift. The gas heater-scan shows no strong per-band daily rhythm (max +9% at 100°C step), indicating a stable, low-VOC hive environment with minimal metabolic cycling in the gas channel — consistent with Hive #3's steady gas resistance sitting exactly on its historical average.
🔬 Correlations & Discoveriestemperature_in vs humidity_in (14d) | r = +0.87Hive #3's strongest deconfounded correlation (r=+0.87, partial r=+0.55 controlling for outdoor weather) confirms active, colony-driven hygroregulation that is independent of the dry outdoor ambient — the brood nest is maintaining its moisture-temperature balance through active metabolic water production and fanning, a textbook sign of a healthy, well-populated colony heading into autumn.📚 Reference: Eouzan et al. 2019 (PLOS ONE / PMC6368279), Human, Nicolson & Dietemann 2006temperature_in vs gas_resistance (14d) | r = +0.7The temp–gas coupling (r=+0.70) on Hive #3 reflects the colony's brood-pheromone and metabolic VOC output rising in step with thermal activity — as heater bees and nurse bees work harder, both temperature and the VOC signature (E-β-ocimene, wax esters, propolis terpenes) rise together, producing a genuine physiological coupling that is a marker of active, healthy brood rearing.📚 Reference: Seeley 1985, Maisonnasse et al. 2010, PLoS ONE 5(10):e13531▹ Action: Monitor Hive #3's battery passively — it touched 3,980 mV during this 24h window, just 2 mV 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.