Data from: A three-phase interrupted development model and web application for predicting timing of <i>Megachile rotundata</i> emergence for synchronization with peak floral bloom

Individual-level emergence timing data for Megachile rotundata (alfalfa leafcutting bee) collected across four laboratory experiments conducted between 2021 and 2023. The dataset was developed to support degree-day modeling of adult emergence timing, with applications to commercial incubation management. Experiments 1 and 2 used constant-temperature incubation across six temperatures to estimate developmental rates and the lower developmental threshold. Experiments 3 and 4 used three-phase interrupted development protocols to validate a model predicting emergence timing following a temperature transfer sequence, and to assess whether model performance generalizes across bee suppliers and years.Experimental design:Experiment 1 (2021) — Model development, cohort 1 Bees sourced from Mennie Farms were moved from cold storage (6°C) directly to one of six constant incubation temperatures (21, 23, 25, 27, 29, or 31°C). Twenty-four plates of 24 bees each were randomly assigned across the six treatments (4 plates per treatment), for a total of 576 bees. Bees remained at their assigned temperature for the duration of development and were checked daily for emergence. Sex was recorded at emergence.Experiment 2 (2021) — Model development, cohort 2 A repeat of Experiment 1 conducted later in the same season to increase model precision and account for temporal variability. Five plates per treatment were used (total 720 bees; all from Mennie Farms). Combined with Experiment 1, the full model development dataset comprised 1,296 bees across 6 temperatures × 2 cohorts × 4–5 plates × 24 bees per plate.Experiment 3 (2022) — Model validation, single supplier Bees sourced from Eggerman Farms were used to validate the degree-day model under interrupted development protocols and to assess whether model predictions generalized beyond the source population used for model development. Fifty-two plates of 24 bees each were assigned to 13 treatments: 12 temperature-transfer treatments plus one constant 29°C control (3 plates per treatment). All transfer treatments began with 29°C incubation for either 1 or 2 weeks, followed by a transfer to 21, 23, or 25°C for 1 or 2 weeks, then a return to 29°C until emergence. Total: 936 bees. Emergence was checked daily and sex was recorded.Experiment 4 (2023) — Model validation, two suppliers A second validation experiment included bees from both Mennie Farms and Eggerman Farms to assess year and supplier effects. All bees were held at 29°C for 1 week, transferred to 21, 23, or 25°C for 2 weeks, then returned to 29°C for emergence. The design was 3 temperature combinations × 2 suppliers × 2 plates × 24 bees per plate, plus 4 control plates at 29°C, for a total of 384 bees. Emergence was checked daily and sex was recorded.Variable descriptions:individual — Integer. Unique identifier for each bee within the dataset.experiment — Integer. Experiment number (1–4). See experimental design above.treatment — String. Incubation protocol for the individual. For constant-temperature experiments (1 and 2), treatment is a single integer representing the incubation temperature in °C (21, 23, 25, 27, 29, or 31). For interrupted development experiments (3 and 4), treatment is encoded as a five-part underscore-delimited string: startTemp_weeksFirstThermophase_transferTemp_weeksCryophase_finalTemp. For example, 29_1_25_2_29 indicates 29°C for 1 week, 25°C for 2 weeks, then 29°C until emergence. Control treatments in Experiments 3 and 4 are recorded as the single integer 29.source — String. Bee supplier. Mennie = Mennie Farms; Eggerman = Eggerman Farms.Plate — Integer. Incubation plate identifier (1–5). Plates are numbered consecutively within each experiment and treatment and correspond to the physical unit of replication. Each plate held 24 bees arranged in a 4-row × 6-cell grid.Row — String. Row position of the individual within the incubation plate (A–D).Cell — Integer. Cell position of the individual within the plate row (1–6).sex — String. Sex of the individual as determined at emergence. F = female; M = male. Blank indicates sex was not recorded; 0 is a data entry artifact (one record in Experiment 4) treated as unrecorded. Individuals with unrecorded sex are excluded from sex-specific analyses.startDate — String. Date incubation began, in M/D/YYYY format.emergenceDate — String. Date the individual emerged as an adult, in M/D/YYYY format. Blank if the individual did not emerge during the observation period.daysToEmergence — Numeric. Number of days elapsed from startDate to emergenceDate. Blank if the individual did not emerge during the observation period.

[
  "005:18"
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{
  "fn": "Torson, Alex, S.",
  "hasEmail": "mailto:Alex.Torson@usda.gov"
}

[
  {
    "@type": "dcat:Distribution",
    "title": "degree_day_dataset.csv",
    "format": "csv",
    "mediaType": "text/csv",
    "downloadURL": "https://ndownloader.figshare.com/files/64149835"
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[
  "Degree day modelling",
  "Megachile rotundata",
  "Pollination",
  "Predictive Model"
]

[
  "005:040"
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{
  "name": "Agricultural Research Service",
  "@type": "org:Organization"
}