No, it isn't quite the peak of the monarch season just yet, but yes their numbers are beginning to increase! People are worried that this year may be one of the lowest ever- however that may not necessarily be the case. This post expands a little further into our census counts described previously in the our post titled "Numbers."
Long Term Data
Over the past 21 years, numbers have ranged from an average of only 9 monarchs per hour along our census route, to almost 360! So far, the first 2 weeks have averaged about 6 monarchs an hour along our census route, but today (9/15/13) alone has already increased to 12 monarchs per hour. The cold front has definitely started bringing more in our way, and this is only the beginning of the season. We still don't know exactly when the "peak" of the season is here, but we will keep you posted! It seems to be a bit delayed, but keep your fingers crossed it'll be higher numbers than expected!
So how do we count our monarchs anyway?
Well, our count is basically an estimate of all the monarchs around the point, but counting them ALL would be physically impossible. Even guaranteeing we are able to see every single one that makes its way along our census route isn't always possible, so we make sure we have experienced researchers who are very focused and have excellent "monarch radar" to see as many as they can.
Our census route runs from Higbees Beach Wildlife Management Area, all the way down to Alexander Ave. in the Boro of Cape May Point. The route has been the same for the past 22 years, and tries to follow the coast of the Cape May Point as much as it can (since migrating monarchs flying over water get pushed in by the wind and appear along the dunes). The census route is approximately 5 miles long, and takes around 20 minutes to complete the survey by car, going at an average of 20MPH. The census is done 3 times daily from September 1-October 31 at 9AM, 12PM, and 3PM. Here is the link to a Cape May Bird & Butterfly Map, which includes the roads used for the census.
While driving along this route, a member of the project has a counter that they punch for each monarch they see within their direct or peripheral vision along the drive. You're probably wondering if other drivers along this route get frustrated with a vehicle going only 20 MPH, and often times they do.. so we always make sure to encourage other drivers to pass the vehicle, since pulling over and stopping or increasing speed to keep up with traffic can alter our data.
We also record the exact time the census run began, the number of minutes total, weather conditions, wind direction and wind speed. All of these factors can affect the number of monarchs seen along the route.
Daily numbers
For daily census numbers of the 2013 season, and a table of the census averages over the past 20 years check out our data page. Daily census counts are usually updated in the evenings, once the day's counts are completed and the data numbers have been calculated.
Why Count Monarchs?
In order to study monarchs and their phenomenal migration, it's crucial to collect data to see how the population is doing. As seen in previous years' census counts, numbers can vary tremendously. It's crucial to study the numbers of monarchs traveling to Mexico so we can link monarch numbers with the factors that affect the migration such as climate change, land development and habitat loss, loss of host plants (milkweed), pesticide use, reproduction success, etc. Education is also extremely important to encourage the planting of milkweed and creation of butterfly gardens and habitats to help increase local populations.
Peak of the Season
The peak of the season seems to be delayed this year and we can't be quite certain of exactly when the largest abundance of migrating individuals will pass through Cape May. Keep checking our website, this blog, and the Facebook page for updates on when the monarchs are arriving and when the best time to visit is! It can be anytime between now, and the end of October. Once the time comes, we are hoping it will look something like this.
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