By Jan Wrede
Guest Columnist

As usual, the purple martins have been in Boerne since mid- February. At the Cibolo Nature Center, this year we spotted the first arrivals on Feb. 17. And today, our established martin colony is bursting with activity. If you want to witness their joyful swooping and chattering, come out just about any time during the day for some acrobatic and musical entertainment.

It is also interesting to note that these lively birds are not nesting yet. You still have plenty of time to mount a new house or clean and repair an existing setup. Right now, there are no nests in any of our 60 martin chambers. At this well-established colony, martins typically spend weeks here before they actually begin building their nests. Most nests are made in late April and early May and most of the martin young fledge from Nature Center nests in late June.

We have two sets of hanging gourds and two apartment houses mounted on poles that are easy to lower for cleaning and monitoring.

They provide a total of 24 gourds and 36 apartments. Through the years, it has become obvious to us that the martins prefer gourds to the houses. For example, last year we had 33 nesting pairs and they built nests in 73 percent of the gourds and in only 47 percent of the apartments.

The size and strength of the nature center martin colony is no accident and it has not always been this successful. When our houses were first put up, we waited two or three years for our first nesting pairs. Then, when they finally chose to nest here, the martins had serious competition from the non-native and aggressive European house sparrows.

Being a martin colony landlord requires more than just putting up a proper martin house. The two keys to attracting and keeping a successful martin colony are monitoring and maintenance. A third issue always at play is predator protection. You become the maintenance man, record keeper and security guard.

About six years ago, we began routine monitoring of the nature center martin colony. In the last four years, we have carefully recorded dates and numbers of sparrow nests removed, martin nests, nestlings and fledglings. We are able to do this thanks to the generosity of dedicated volunteers: 2008 is the fourth year that Gary Younglove and David Doss are monitoring the Nature Center colony!

Each spring before the first birds arrive, Gary and David do the annual spring housecleaning. They lower the houses and gourd assemblies; wipe each chamber and dust with diatomaceous earth to discourage bird mites. Soon after the middle of February, they open the chambers so the early birds can roost in them and get protection from late winter wind and cold.

Then, the monitoring team begins weekly removal of sparrow nests. Counting and recording martin nests, nestlings and fledges continues until young birds have fledged.

This routine attention has made a huge difference in the health and productivity of our colony. The nature center colony fledged 44 martins in 2004, 81 in 2005, 93 in 2006 and 141 in 2007!

If you want more information on how to start or maintain a successful martin colony, the Purple Martin Conservation Association Web site at www.purplemartin.org is an excellent resource.

Also, you can report the first arrival date at your martin colony to an international database at www.purplemartin.org/scoutreport/.