Monarch Monitoring Project

Mapping Migration Distribution Data

Background:

The exact patterns of the spring Monarch migration are not yet completely understood. Therefore, scientists are actively collecting data using projects such as the Monarch Larva Monitoring Project to better map and understand when and where Monarchs appear following their overwintering period.

Complicating this matter is the issue of climate change – as the climate of North America changes, so too do the dates when the Monarch’s vital food source, milkweed plants, begins to emerge from their winter dormancy. The question remains then, what impact is climate change having or what impact could it have in the next century on the migration of Monarch butterflies in North America.

To investigate this issue, you are being asked to map data from previous years of observed spring Monarch migrations in order to compare what effects weather/climate shifts have had (if any) on the distribution of Monarchs at given benchmark dates in the migration phase.

Directions:

1.  Go to http://www.learner.org/jnorth/maps/Maps.html

a.  You will find a series of observational maps and data for a variety of organisms. We are specifically interested in two of these data sets: Monarch butterflies and Milkweed (second row of maps)

2.  Begin with the Monarch butterflies – click on the “sightings” link below the Monarch Butterflies map

3.  In the user interface, select the following parameters: 1. Monarch Adult (first sighting) and 2. Show sightings made in the last 365 days. Click on the button to display the records.

4.  Beginning with the March data from the most recent year, divide each month into the first 10 days, the second 10 days, and the remaining days of the month until the end of the month.

5.  Find the point from the first 10 days of March with the largest latitude value. Plot that point on your map using its latitude and longitude coordinates.

6.  Find the point from the first 10 days of March with the smallest (most negative) longitude value (this should be the most western point). Plot that point on your map using its latitude and longitude coordinates.

Hint: this point may be the same as the first point. That’s just fine!

7.  Find the point from the first 10 days of March with the largest (least negative) longitude value (this should be the most eastern point). Plot that point on your map using its latitude and longitude coordinates.

Hint: this point may be the same as the first or second point. That’s just fine!

8.  Draw a smooth line that connects these points. Label this line on your map with the number 1.

9.  Repeat the previous four steps for all 10-day periods through the month of July. There should be a total of 15 lines. Give each line its own number counting up from 1 to 15.

Questions:

1.  What states saw the earliest entrance of Monarchs into their areas? Explain why you think they enter these states first.

2.  If there was a major freeze event in the central Midwest states (Missouri, Kansas, Iowa, etc.), how do you think the Monarch migration pattern would change? Explain your reasoning.

3.  If many months of drought conditions were to impact precipitation levels in the southwest on the eastern side of the Rocky Mountains (Northern Texas, Oklahoma, Colorado, Wyoming, etc.), how do you think the Monarch migration pattern would change? Explain your reasoning.

4.  What environmental conditions do you think are present in Florida that could possibly prevent Monarch butterfly populations from becoming too numerous (i.e. why don’t they overwinter there more)?