"There were thousands of them in the fall swarming over the Montrose peninsula," said Herb Siegel, who takes care of the purple martin apartments. Where did they go?
"We're not sure. Well, they may have lost their natural housing to the starlings," said Siegel.
The bird houses Siegel watches over are cranked down on the poles so the baby birds or nestlings can be checked out.
"The Park District got involved in 2002 by installing 18 Purple Martin houses along the lakefront to provide habitat for a bird that no longer has much natural habitat in the eastern United States," said Rebecca Schillo, Chicago Park District.
The program has been successful. The first year there were less than ten nestlings. This year there are 102. And, there are still some eggs that might hatch successfully.
It used to be thought that purple martins were great to have around because they ate tons of mosquitoes. That's not true because purple martins fly too high to eat mosquitoes. But if you happen to be a dragon fly or a butterfly; look out! You're days are numbered.
"The parents catch dragonflies and butterflies for them ... and they bring them back to the nest and sometimes break them up into pieces that the young can handle," said Siegel.
Dragonflies! That's OK; that's easy to stomach. But beautiful butterflies, that's harder to swallow.