Want to watch monarchs and join our network? In this section we describe a number of methods currently used by sites in our network, for those interested in starting a new monarch migration monitoring site.

As mentioned elsewhere in this website, our network currently lacks monitoring sites in the midwest and central states. There are also places in Canada (especially in southern Ontario and Quebec) where large number of monarchs pass through during their fall migrations. Monitoring sites could easily be set up at these locations.

To begin with, there are many ways to survey or count migrating monarchs. We do not neccessarily prefer one method over another, however there are advantages and disadvantages to each, and no one method provides the best results. For this reason, if you are considering starting a new monarch monitoring site, it may be best to combine two of the methods described below. What is most important is that the same method be applied each year. After several years of collecting data, a pattern may begin to form in the numbers tallied per year. That pattern is the important thing, in terms of monitoring the size of the population.

It is important to point out here that tagging is not appropriate for surveying the number of monarchs that pass by a site as it relies on capturing monarchs, and there are many variables affecting the 'catchability' of monarchs - wind conditions, personal netting skill, flying height of the monarchs that day, etc. However we do recommend tagging for measuring stopover lengths, recapture rates, etc (see monarchwatch.org for info on tagging).

The survey methods we recommend for monarch monitoring are the driving census, walking census and roost count.

Items you will need for these methods - hand tally (i.e. a clicker), clipboard and perhap a pair of binoculars if you are conducting a walking census. A car can come in handy too for the driving census method!

 

1. The Driving Census

DESCRIPTION: As the name implies, this method involves driving slowly along a standardized route (a road) a number of times each day during the migration season (for the fall it's usually throughout the months of september and october) and counting all monarchs you see out the window using a hand tally (a clicker). More recently, observers have begun using two clickers (pictured right) and recording monarchs flying and not flying, to differentiate between actively migrating and 'bivouaced' monarchs

NOTES:

The surveys should be conducted 2 or 3 times daily - 9 am, 11am and 3 pm are good times.

The car must be driven approximately 25 miles per hour during the census - no stopping!

The route should be a minimum of 5 miles long and should cover a variety of habitats

The route should be on roads with little traffic, as the car will be moving slowly

Only one observer in the car can do the counting

Advantages of this method - it covers more ground

Disadvantages - the observer can only see monarchs near ground level

 

2. The Walking Census

DESCRIPTION: A variation on the driving census. It's really the same thing, only the observer walks a standardized route (a nature trail, like the one pictured above for example) several times daily during the migration season, counting all monarchs seen.

NOTES:

As with the driving census, the walking census should be conducted 2 or 3 times daily - 9 am, 11am and 3 pm are good times.

The trail you pick should cover as many habitats as possible. If there is a known roosting spot, ensure the trail passes by it so that the roosting monarchs are censused. If there are known nectaring sites (like a flower garden or a butterfly bush), try to encompass those too.

Only one person should do the counting

Advantages of this method - the slower pace means seeing more monarchs, getting more accurrate counts on clusters, groups, etc. Also, the observer can look for monarchs near the ground or flying high above

Disadvantages - not as much ground is covered here as with the driving census

 

3. The Roost Count

DESCRIPTION: This method is not widely-used, but if done properly and at the right location, can yield great data. It can only be conducted at a location where monarchs are known to roost every year during their fall migrations. Thus, some advanced knowledge of the area is needed before this method can be used.

For this method, the observer visits the roost area once or twice daily during the fall, either at dawn or at dusk (or both), and records the number of roosting monarchs seen.

At right is a picture of monarchs clustering on a known roost tree on the southern end of the Delmarva Peninsula, VA, in the fall.

NOTES:

Roosting monarchs are great for counting, but these areas can also be great for catching (and tagging) monarchs. However, keep in mind that monarchs roost at night because the temperature drops too low for them to fly. for this reason, we do not recommend capturing monarchs in the evening as they will not be able to fly back up to their roost tree when they are released. Save the netting for the mornings, when monarchs can easily warm themselves with sunlight.

*Remember for the best results it may be neccessary to combine two of these methods*