Mapping Brood XIX in Virginia Progress Report - Day 2

Mapping Brood XIX in Virginia Progress Report - Day 2

Here in Williamsburg the morning started out very cloudy and I was worried that we were going to get rain. But eventually the sun did shine through and all was fine.

Creating distribution maps can be a long, boring and drawn-out process. It involves driving around and paying attention to what you see and hear in a particular area where periodical cicadas are expected to be found. You then must take careful observational notes about the site. Things like density of cicadas, single male calling vs multiple male chorusing, what time of day, what the temperature is plus a myriad of other important criteria. Then with a hand-held GPS unit the coordinates must be recorded and then you decide where to go next to get the next data point. I like to take data points every mile or so in order to be as accurate as possible. But this process is often time consuming but its worth it. It's this accumulation of data that I use to construct species distribution maps.

However, sometimes on those rare occasions I get to have company and fortunately today was one of those days. I met a gentleman by the name of Don (I won't use his last name to protect his privacy) who was my navigator for part of the day. I met Don through this very web site when he reported the locations of several periodical cicadas emergences around the Williamsburg area.

When I told him I was heading here, he offered his services to help. I of course jumped at the chance because that way, when you have a navigator; and one who is familiar with the area, this divides up the data-collecting tasks between two people quite nicely and goes a lot smoother.

About Don

Don used to work for the Wall Street Journal as an editor and has since retired. He worked with investigative reporters and reported for the financial news industry. Don also dabbled briefly with developing web sites when the internet and coding in HTML was in its infancy.

Like myself Don didn't have formal training to develop web sites but was interested in the technology and wanted to learn something new. So he just learned it on his own.

Don also met his wife - Ellen - at the Wall Street Journal and I think he said that they've been married since the beginning of time! Just kidding, I actually forgot to ask how long they've been married. But suffice it to say that I am assuming they've been living happily together for many years.

Originally from Connecticut Don has only lived in Virginia for about 12 years. However, I was amazed at the amount of knowledge he has amassed about all the historical sites in and around Williamsburg that we visited while mapping.

Together we covered a lot of area to the south and West of Williamsburg.

Arriving back at Don's place, he offered me a beer so I ended up staying for several hours. Along with Ellen, we talked for several hours about cicadas and cicada killers and other things like the evolution of humans and how we came to be along with a bunch of other cool and interesting topics. Ellen is a very smart and charming woman who seems to have a great interest in science and nature in particular.

It's always great meeting people like Don and Ellen who are willing to help out and lend a hand. This is one of the reasons I do this. It's the opportunity to meet new and interesting people and make some friends along the way.

Back to Mapping.

After saying our goodbyes I was back on the road on my own mapping the brood. I am a bit satisfied with the number of data points I collected today. Both positive and negative data points as well. You can see them on the distribution map by zooming in to Virginia to see the amount of area that was covered.

My goal as in previous periodical cicada emergences to to update these maps daily. So, you can return at the end of each day to see the progress that has been made.

Population Densities and Distribution of Species.

The areas that had periodical cicadas seemed to be mostly M. tredecim. While M. tredecassini was also found they just weren't there in the high numbers that M. tredecim were. I was able to detect sporadic single calling males among the 'decims and they were very high in the trees so I was unsuccessful in obtaining any specimens. This may be due to the type of habitat or terrain or for some other factors not immediately apparent. Suffice it to say that, M. tredecassini were not found in huge aggregations in any of the areas surveyed directly south and east of Williamsburg.

M. tredecim was in high numbers in many areas and were low enough to capture. I managed to obtain several more voucher specimens, mostly male. Another interesting observation was that I was not able to detect females ovipositing or any mating among the 'decims.

I think I will close this article with a few shots of a male Magicicada tredecim's abdomen which is a lot more orange and brightly colored compared to their 17 year counterparts (Magicicada septendecim). When I get home, I think I'll need to do some morphological comparisons between the two.