AI Beehive Health Report — 2026-09-25

As of September 25, 2026, all four colonies are acoustically rock-solid — every sound spectrum across the apiary is within ±2.5 dB of its own historical baseline, confirming worker populations are fully intact — while the apiary-wide September cooling arc continues with outdoor temps ranging 52–68°F (11–20°C) and clean outdoor air (848 kΩ gas resistance); Hive #2 remains the sole 'watch' hive, now one week into a confirmed thermal step-change that has deepened further to a 24h avg of 64.1°F (17.9°C), with stable acoustics pointing to a broodless interval as the leading explanation ahead of a routine inspection.

Across all four hives, the deseasonalized temperature–gas resistance correlation (r = −0.59 to −0.74) is a consistent apiary-wide signature: as brood rearing contracts and in-hive temperature falls this September, the VOC load rises slightly — consistent with reduced brood pheromone production being offset by propolis sealing activity and honey ripening as colonies shift toward autumn preparation (Maisonnasse et al. 2010; Bankova et al. 2000).

All four hives maintain clear daily vibration fanning rhythms with 80–120 Hz as the dominant band; daily peaks range from ~1.5× baseline (Iris, Hive #1) to ~3.7× baseline (Hive #2), consistent with each colony's activity level in late September; outdoor temperatures ranging 52–68°F (11–20°C) with a steady barometric tendency (−0.22 hPa/3h) and clean outdoor air support normal foraging conditions, and all diurnal temperature oscillations are buffering correctly against ambient with outdoor leading in-hive by 2–5 hours.

• Iris warning Score: 72/100
  📋 Overall Health

  Your Iris hive has a fully intact worker population — sound is rock-solid at −11.1 dBFS (right on the −10.8 dB all-time baseline, all bands within ±2.5 dB) and vibration kurtosis of 2.5 is normal — but the 14-day cooling drift has deepened to a 24h avg of 74.6°F (23.7°C), now 11.2°F (6.2°C) below the all-time avg of 85.8°F (29.9°C); the stable-to-louder acoustics confirm this is a broodless or brood-break interval with the full adult population present, not a population-loss event. Humidity at 54.1% is comfortably within the 50–70% healthy range, and the battery is charging at 4,040 mV — both nominal; on your next routine visit, a quick check for fresh eggs or capped brood will confirm whether the colony is in a requeening gap or a natural seasonal contraction.

  🌅 Diurnal Cycle Patterns

  Daily temperature oscillation averages +6.7°F (+3.7°C) over 24h (range 71.8–77.6°F / 22.1–25.4°C), which reflects ambient coupling through the screened floor as brood mass contracts — the deseasonalized analytics confirm outdoor leads in-hive by ~230 min, a healthy thermal-mass buffering signature. Vibration shows a clear daily fanning rhythm (14/15 days with a distinct peak, baseline ~16.5 mG rising to ~24.6 mG, avg 1.5×, dominant band 80–120 Hz at −10.1 dB, matching the all-time avg of −10.0 dB exactly); the per-band acoustic rhythm shifted from 260–350 Hz to 100–150 Hz between the first and second half of the window, with 100–150 Hz gaining +3.2 dB — worth watching but within the ±5 dB threshold; gas heater-scan shows the strongest daily rhythm at 150°C (+14% swing), with the low-temperature steps (100–200°C) tracking the humidity-linked psychrometric cycle rather than a discrete VOC chemistry change.

  🔬 Correlations & Discoveries

  temperature vs humidity (14d) | r = +0.81

  The strong deseasonalized r=+0.81 between in-hive temperature and humidity in Iris reflects a psychrometric relationship: as the brood cluster contracts and temperatures fall below the typical 93–97°F (34–36°C) brood-heating band, the absolute water content of the air reads as higher RH% at cooler temperatures — the inverse of the classic warm-core/low-RH signature; the rising colony-state PCA index (dominant channels: humidity, temperature, gas) is consistent with the colony transitioning toward a lower-activity autumn state while maintaining active hygroregulation.

  📚 Reference: Eouzan et al. 2019 (PLOS ONE / PMC6368279), Human, Nicolson & Dietemann 2006, Ellis et al. 2008, J. Insect Physiol.
  ⚠️ Issue: 14-day cooling drift of −13.4°F (−7.5°C): 24h avg now 74.6°F (23.7°C), 11.2°F (6.2°C) below all-time avg of 85.8°F (29.9°C) — acoustics confirm population fully intact; consistent with a broodless/brood-break interval; queen/brood status worth confirming on next routine visit.

  ▹ Action: On your next routine visit, check Iris's brood frames for fresh eggs — the perfectly stable and slightly louder acoustic spectrum confirms the full worker population is present and active, and a quick brood check will clarify whether this cooling reflects a natural requeening gap or seasonal contraction.
• Hive #2 warning Score: 63/100
  📋 Overall Health

  Your Hive #2 remains acoustically rock-solid — all 10 sound bands within ±1.6 dB of the all-time baseline (24h avg −16.4 dBFS vs. all-time −16.5 dBFS) and vibration at 33.5 mG (kurtosis 3.1, dominant 80–120 Hz) confirms the adult worker population is fully intact — but the confirmed September 19 thermal step-change has deepened significantly, with the 24h avg now 64.1°F (17.9°C), a full 25.6°F (14.2°C) below the all-time avg of 89.7°F (32.0°C) and tracking close to the outdoor ambient range of 52–68°F (11–20°C); the most parsimonious explanation for this degree of cooling with a perfectly stable acoustic population is a broodless interval — the colony is not heating a brood zone right now — and confirming queen/brood status on your next routine visit will clarify this. Humidity at 59.9% is comfortably in the healthy 50–70% range, and the battery at 4,052 mV is stable.

  🌅 Diurnal Cycle Patterns

  Daily temperature oscillation is now +12.6°F (+7.0°C) — the widest in the apiary — with the 24h range running 59.8–69.4°F (15.4–20.8°C), closely mirroring the outdoor ambient cycle as expected for a colony with minimal or no brood mass to buffer the swing; vibration shows the strongest daily rhythm in the apiary (all 6 bands cycling, dominant 120–160 Hz strengthening from 5.1 to 9.4 dB amplitude over the window, and all bands gaining +3.5 dB in the second half), suggesting the bees are increasingly active in the fanning/ventilation register despite the cooler core — consistent with a populated but broodless cluster maintaining normal activity. The gas heater-scan shows 8/10 bands cycling daily, with the dominant rhythm shifting from 150°C to 100°C and low-temperature steps gaining +47–48% swing amplitude; because these low-temperature steps are most sensitive to humidity and the in-hive humidity is now at 59.9% (notably elevated vs. the all-time avg of 48.2%), the gas shift is best read as a humidity-driven MOX artifact accompanying the cooler, more ambient-coupled environment rather than a discrete new VOC source — confirmed by the change-point analytics which show the gas resistance step-change coinciding exactly with the September 19 temperature step-change.

  🔬 Correlations & Discoveries

  temperature vs gas_resistance (14d) | r = -0.7

  The deseasonalized r=−0.70 (and partial r=−0.91 controlling for outdoor weather) between in-hive temperature and gas resistance captures a genuine colony-metabolic coupling: as brood rearing paused around September 19 and the in-hive temperature fell sharply, E-β-ocimene and other brood pheromones declined while the MOX sensor baseline shifted upward (higher resistance = lower VOC load) — both the temperature and gas change-points coincide on September 19, consistent with a brood-break transition rather than a pathological event; the z=−3.1 gas anomaly flags the current reading as lower than the post-step-change rhythm predicts, likely reflecting the low-temperature MOX steps' humidity sensitivity as RH rose to 59.9%.

  📚 Reference: Seeley 1985 & 1995, Maisonnasse et al. 2010, PLoS ONE, Burgues & Marco 2018, Sensors 18(2):339

  vibration_rms vs vibration_kurtosis (14d) | r = -0.58

  The negative deseasonalized r=−0.58 between vibration RMS and kurtosis is the expected signature of a healthy, active colony: on high-activity periods the RMS rises from broadband fanning and foraging effort while the waveform becomes more Gaussian (kurtosis falls toward 3.0), whereas quiet periods show lower RMS with slightly more impulsive structure; kurtosis at 3.1 is exactly normal, and the strengthening daily vibration rhythm (all 6 bands cycling, peaks reaching ~54.5 mG) confirms a full, well-organized worker population.

  📚 Reference: Ramsey et al. 2020, Sci. Rep. 10:9798, Tautz 1996
  ⚠️ Issue: Confirmed September 19 thermal step-change now at 14-day cooling drift of −30.6°F (−17.0°C): 24h avg 64.1°F (17.9°C) is 25.6°F (14.2°C) below all-time avg of 89.7°F (32.0°C) and approaching outdoor ambient range — acoustics confirm adult population fully intact; consistent with a broodless interval; queen/brood status warrants confirmation on next routine visit.

  ▹ Action: On your next routine visit, check Hive #2's brood frames for fresh eggs and confirm queen status — the perfectly stable acoustic spectrum and robust daily fanning vibration confirm a full adult population is present, and a brood check will clarify whether this is a natural brood-break/requeening gap or the colony has entered autumn broodlessness ahead of schedule.
• Hive #1 healthy Score: 84/100
  📋 Overall Health

  Your Hive #1 continues as the most thermally stable colony in the apiary — the 24h avg of 78.9°F (26.0°C) represents a modest −2.1°F (−1.2°C) drift from the all-time avg of 81.0°F (27.2°C), and all 10 sound bands are within ±0.1 dB of the all-time baseline (24h avg −16.4 dBFS matching all-time −16.4 dBFS exactly), confirming a full and active worker population heading deeper into autumn. Humidity at 48.2% is just below the 50–70% optimal band but reflects the dry September ambient ventilating through the screened floor — no colony concern; battery at 4,178 mV is the strongest in the apiary and charging, and vibration kurtosis of 2.6 is normal.

  🌅 Diurnal Cycle Patterns

  Daily temperature oscillation of +7.0°F (+3.9°C) (range 75.1–82.1°F / 23.9–27.8°C) is well-behaved for a mid-box sensor in an insulated Apimaye hive on a September day; the 14-day cooling drift is the gentlest in the apiary at −2.5°F (−1.4°C), consistent with Hive #1's position as a three-box colony with more thermal mass. Vibration shows a reliable daily rhythm (14/15 days, baseline ~15.8 mG to ~23.9 mG, avg 1.5×, dominant 80–120 Hz at −10.4 dB vs. all-time −10.5 dB), and the gas heater-scan is the most rhythmically complete in the apiary (10/10 bands cycling, strongest at 150°C with +30% daily swing) — the well-structured gas daily cycle reflects the colony's metabolic respiration pattern coupling to ventilation, consistent with healthy CO2/VOC circadian dynamics (Bencsik et al. 2023, Seeley 1974).

  🔬 Correlations & Discoveries

  temperature vs gas_resistance vs gas_resistance_outdoor (14d) | r = +0.53

  The deseasonalized r=+0.53 between Hive #1's gas resistance and the outdoor hub gas resistance — after removing the shared diurnal cycle — indicates a genuine fraction of this hive's VOC environment is tracking regional outdoor air quality rather than being purely colony-generated; this is the expected 'air sampler' behavior of a hive with a screened bottom board drawing ambient air through the colony, and it means the apiary-wide outdoor gas baseline (~848 kΩ, clean air) is a useful normalizing reference for this hive's ~490 kΩ readings, which are colony-elevated but not anomalous.

  📚 Reference: Burgues & Marco 2018, Sensors 18(2):339, Ferrari R.M. et al. 2025, Commun. Earth Environ., Bosch Sensortec BME688 datasheet
  ▹ Action: On your next routine visit, confirm fresh eggs in Hive #1's brood frames — everything here is settled and this colony is the apiary's stability anchor heading into autumn.
• Hive #3 healthy Score: 76/100
  📋 Overall Health

  Your Hive #3 is acoustically healthy and worker-population intact — all 10 sound bands within ±2.1 dB of the all-time baseline (24h avg −16.1 dBFS vs. −16.3 dBFS all-time), with the only notable shift a +2.1 dB gain in the 500–600 Hz band that is well within monitoring range and not corroborated by any temperature or vibration anomaly; the 14-day cooling drift of −11.3°F (−6.3°C) (24h avg 78.3°F / 25.7°C, 8.0°F / 4.4°C below the all-time avg of 86.2°F / 30.1°C) is consistent with the apiary-wide September brood-contraction arc, and the louder-than-baseline sound confirms the adult population is fully present. Humidity at 55.3% is solidly within the healthy 50–70% range (wide 24h range of 47.0–70.9% reflecting normal ventilation through the four-box architecture); battery at 4,000 mV is charging (+26 mV over 24h) and above its all-time low of 3,968 mV — continue passive monitoring as autumn solar charging declines.

  🌅 Diurnal Cycle Patterns

  Daily temperature oscillation of +9.0°F (+5.0°C) (range 72.5–84.7°F / 22.5–29.3°C) is the second-widest in the apiary, reflecting the four-box configuration's larger air volume and the sensor's position in box 2 of 4; vibration shows a reliable daily rhythm (14/15 days, all 6 bands cycling, dominant 80–120 Hz at −8.8 dB vs. all-time −8.7 dB, baseline ~19.1 mG to ~34.4 mG, avg 1.8×), and the dominant vibration rhythm band shifted from 5–20 Hz to 120–160 Hz between the first and second half of the window — consistent with a colony gradually shifting from low-frequency DVAV recruitment signals toward higher-frequency fanning effort as September temperatures cool. The gas heater-scan shows 10/10 bands cycling with a dominant rhythm shift from 200°C to 100°C, and the low-temperature steps (100–150°C) strengthening (+14% → +54% swing); the change-point on September 23 (+15,209 Ω step upward, i.e. slightly cleaner air) coincides with a humidity rise toward 70.9% — the low-step MOX response to humidity changes explains this shift, and the gas baseline at ~99 kΩ remains right on the all-time avg of ~96 kΩ.

  🔬 Correlations & Discoveries

  humidity vs gas_resistance (14d) | r = -0.67

  The deseasonalized r=−0.67 between in-hive humidity and gas resistance in Hive #3 reflects MOX sensor physics: the four-box architecture with screened floor creates wider humidity swings (47–71% over 24h), and rising humidity adsorbs onto the SnO2 sensing layer, lowering resistance independently of any VOC change — the September 23 gas change-point coinciding with a humidity rise is a textbook humidity-confound artifact, not a new chemical event in the hive; interpreting these gas variations requires always checking the concurrent humidity trace first.

  📚 Reference: Burgues & Marco 2018, Sensors 18(2):339, Abidin et al. 2022, Sensors 22:3301, Ellis et al. 2008, J. Insect Physiol.
  ⚠️ Issue: Battery at 4,000 mV is near its all-time low of 3,968 mV — monitor passively as autumn solar charging continues to decrease.

  ▹ Action: On your next routine visit, check Hive #3's brood frames for fresh eggs — the stable acoustic spectrum and on-baseline vibration confirm a full worker population, and a brood check will clarify whether the sustained cooling drift reflects seasonal contraction or a brood-break interval.

  ▹ Action: Monitor Hive #3's battery passively — currently 4,000 mV and charging; no action needed yet, but keep an eye on the trend over the coming weeks as autumn days shorten.