In 2004 the Brood X emergence in Long Island New York and
New Jersey ranged from disappointing to depressing, with one lone
exception: Princeton, New Jersey. Other areas of the country, like
Virginia, Maryland, Washington D.C. and Ohio witnessed fantastic emergences.
The truth is the New Jersey and Long Island Brood X populations have been dwindling
for generations. I did not bother to make a New York Brood X t-shirt because I did
not expect an emergence there (I only made a shirt after a dozen or so requests).
So why are Magicicada populations dwindling? Entomologists will study the facts and arrive at an educated answer, but in the meantime, let’s explore the clues to the Magicicada mystery of 2004.
If you listened to the media in the New York/New Jersey area, you would think the Brood X emergence would rival locust plagues promised in the Bible. After many interviews with the press, I believe that they were not guilty of intentionally sensationalizing the emergence. They were fooled like the rest of us: mislead by archaic or misleading brood maps, or outdated information on web sites. While a site like Cicada Mania can be very informative, to get the most accurate information the media really should contact professional entomologists like Dr. Chris Simon and her associates.
One important detail the press neglected to convey is that Magicicadas do not appear everywhere when they emerge: they only emerge in specific locations.
Location, Location, Location
In any given state in which Magicicadas emerge only a select number of counties and towns will experience them — people in New Jersey assumed that the entire state would be inundated, but this was not the case.
It is also common for cicadas to emerge in vast numbers on one side of a town, while on the other side of town, only a handful will emerge. A new housing development will probably have zero cicadas, while the woods across the road might be chock full of them.
Brood Maps and location tables can be misleading because they often point to a general area. A map or table might say cicadas exist in a particular town, but really they only emerge in two or three very specific locations within that town.
Development and Sprawl
Think back 17 or 34 years (if you’re old enough) and try to remember what your town and state was like back then. New Jersey for instance has experienced tremendous increases in population and new housing development. Cicada habitats are destroyed as populations expand and communities sprawl across the landscape. If a population of Magicicadas stands in the way of a Wal-Mart or a neighborhood of McMansions, the cicadas are history.
Pesticides and Environmental Toxins
Homeowners, businesses and the government dump tons of pesticides into the ecosystem every year. West Nile Virus spraying, although necessary, may also have an impact on Magicicada populations. Perhaps all these chemicals have taken their toll on the Magicicadas?
Given the number of superfund sites in New York and New Jersey (do a search: http://www.epa.gov/superfund/sites/locate/index.htm) I’m surprised anything lives in either state.
Cicadas are fast food for starlings, sparrows, and other predators. In areas were cicada populations are healthy, the birds can’t keep up with the massive buffet of cicadas, and the Brood survives. In areas like Long Island and New Jersey where the cicada populations are weak, birds quickly decimate emerging Brood. European starlings and English sparrows are called an "invasive species" because they are not native to North America. Native insect species, such as cicadas, have not evolved defenses against these invasive species. Likewise native bird and bat species have not evolved the ability to compete with these newcomers.
Hundreds of years ago the smallpox virus destroyed Native American populations, because Native Americans had not evolved immunities to this dreadful disease. Similarly, an invasive species could destroy many native North American animals and plants.
For more information about invasive species and what you can do about them, visit the Invasive Species Weblog.
The past few springs have been cold and rainy in the Long Island and New Jersey area. Perhaps the weather has delayed the Brood X emergence?
Occasionally Magicicadas will emerge a year or so later than they were supposed to. Perhaps a few Brood X cicadas will emerge next year? Only time will tell.
So what can we do to ensure that Magicicadas will be around for future generations? What can we to do to ensure that the media doesn’t misreport future emergences?
- Magicicadas could be declared an endangered species, and they should be protected from development.
- Discourage the use of pesticides when alternative and natural means of pest control exist.
- Educate yourself about invasive species and learn what you can do to control them.
- Encourage entomologists to update brood maps and to create specific location information. Place caveats on current brood maps indicating waning or endangered populations.