The impact of temperature on the reproductive development, body condition, and mortality of fall migrating monarch butterflies in the laboratory

Overwintering populations of the monarch butterfly, Danaus plexippus, have been in decline for the past 30 years. Several hypotheses for the decline have been proposed including summer and winter habitat loss and migration mortality due to non-senescing milkweeds and the parasite Ophryocystis elektroscirrha (OE). How climate change will affect migration physiology, however, has been understudied. This is surprising because warmer temperatures will likely destabilize reproductive diapause, a physiological strategy central to migration and overwintering success. Here, we exposed wild-caught migrating monarchs to different field-realistic migratory temperatures under laboratory conditions for 30 days, followed by different overwintering temperatures until death. During the migratory phase, warmer temperatures reduced male body condition, increased male mortality, increased mating frequency, and caused females to prematurely abandon diapause and invest in oocytes in the absence of milk..., , , # Data from: The impact of temperature on the reproductive development, body condition, and mortality of fall migrating monarch butterflies in the laboratory

[https://doi.org/10.5061/dryad.sf7m0cgg5](https://doi.org/10.5061/dryad.sf7m0cgg5)

## Description of the data and file structure

Migrating monarch butterflies collected in Oklahoma in October 2023. Placed in two simulated migratory temperature treatments (cold and warm) under laboratory conditions. After 30 days, monarchs were placed in two simulated overwintering temperature treatments (cold and warm) until their death. For all files, missing values were replaced with \"N/A\".

### Files and variables

#### File: femmigration.xlsx

**Description:** Female migration data file

##### Variables

* ID: ID of the butterfly
* Sex
* Iwgt = Initial weight in grams
* VL = wing vein length in mm
* ICON = initial condition calculated as Iwgt/VL.
* MTRT = Migration Treatment (cold or warm)
* MINC = Migration incubator group
* Mcage = migrati...,