By Joe Sebastiani, Seasonal Programs Team Leader and Bob Strahorn, Delmarva Ornithological Society
On May 27, 2011, I conducted a Breeding Bird Atlas survey with Bob Strahorn and Carol Majors for the State of Delaware. We walked and drove around block 21, which is south of Newark to find evidence of breeding birds. After birding around the Cooch-Dayett Mills property along the Christina River, we drove past Glasgow High School and noticed Purple Martins flying around the parking lot. We stopped and did not see any martin houses, and quickly realized they were going in and out of street lamps.
The downward-facing glass globes looked like they were broken by rock-throwing teenagers or perhaps angry, venting teachers at the school. At any rate, the vandals created perfect nest sites for the Purple Martins. Usually in our area, Purple Martins use houses and artificial nest boxes put up for them. Historically, they nested in rock crevices, old woodpecker holes, and other such cavities. Many still use these natural cavities out west, but in eastern North America, they are almost completely found nesting in non-natural “martin apartments”.
If you conduct a quick google search, you can easily see that Purple Martins are known to do this on occasion, but none of us had ever seen it, or heard of it happening in Delaware. The oldest record I could find references Purple Martins nesting in electric arc-light caps in Vergennes, Vt in 1897. (Auk, Vol. XIV, 1897). Obviously they figured this out long ago, but it is still really interesting to see how adaptable this species is. Having trouble attracting them to your property? Maybe this method will work for you!
In all, we think there were four pair at this site, plus a pair or two of European Starling using other broken street lamps. The Delaware Nature Society will be contacting the school to see if they would consider installing a martin box to expand the colony next year.