2019 Monarch Data
Caterpillars remained caterpillars for approximately 15 days growing steadily to just below 50 mm in length. Their average daily growth rate is 3.1 mm/day and their 14 day length percent growth is over 1500%! Their ONE DAY length percent growth is usually around 35%!
Caterpillars grow from an estimated 1 mg to approximately 1800 mg in 15 days. Their average daily growth rate is 120 mg and their 15 day mass percent growth is over 100,000 percent! Their ONE DAY mass percent growth is usually around 50%!
The 2019 monarchs grew faster than all previous years monarchs. They also grew larger than all other years except for 2012. It is hypothesized that developing in south facing windows with considerable sunshine may have affected their growth rate.
The above histograms show the frequency distribution of the raised monarchs for years 2010 to 2019. The 2019 monarchs fell within the normal range of around 45 mm for maximum length reached and 1600-1900 mg for maximum mass reached. However, they grew quicker than the nne year norm being in the caterpillar stage for 13 days and pupa stage for 12 days.