Weather can be a Predator!
Purple Martin Preservation Alliance
"Most landlords, including the PMCA, simply did not realize that [the poor weather] was severe enough to do the damage that it did in time to intervene with supplemental feeding." - Purple Martin Update, Fall 2009, regarding 90% nestling mortality (starvation), caused by poor weather at a PMCA colony as well other Purple Martin colonies.
As a member of the PMCA since day one, a former staffer who helped develop the supplemental feeding technique, and someone who has been involved with martins for almost 30 years, I was saddened to hear of the deaths of so Purple Martin nestlings at the PMCA research colony, as well as other colonies, this past summer.
Many people have worked hard to manage existing colonies or start new colonies, and it is distressing to think that so many nestlings that might have been colony-starters next year never made it out of the nest, especially when much of the loss could have been avoided. Many first year breeders that may have been forced to disperse to start new colonies in 2010, will now have ample room to move into already established colonies that experienced heavy nestling mortality in 2009.
It’s tough to understand how this happened; it seemed readily apparent that the weather was consistently poor enough to be considered severe for martin parents trying to feed a large brood of hungry nestlings. During this nestling-killing weather, I fed scrambled egg at two medium-sized colonies within several miles of me for three days in a row.
Many other landlords
also realized the weather was deadly and intervened with supplemental feedings.
They experienced up to a 40% nestling mortality rate, but still saved many of
their nestlings. Diane Oberlander of Erie Co., PA lost 40% of her nestlings despite
heavy and frequent feedings; 1-2 survived per nest. Duke Snyder of Butler Co.,
PA lost 72 of 192
nestlings (38%) even though he fed heavily. Other landlords who realized the
weather was very poor and who provided supplemental feedings include: Bob
Allnock, Dean Kildoo, and Roy Bauder, all from western PA. To most of us, supplemental feeding is no longer
entertaining, but it is still a necessary conservation task. My gratitude to those
who worked diligently to save their nestlings.
As for the 90%+ nestling mortality at many colonies where landlords did not provide supplemental feedings, it is disappointing and disheartening to realize that many of these birds died when the means to save them existed! Aggressive supplemental feeding could have prevented many nestling deaths. Adverse weather kills more martins than all other causes of mortality combined, and it must be considered a potential super-predator. Just like you need to have a predator guard on your martin house pole at all times when the martins are present, to prevent a raccoon from climbing it and eating your martins, you need to be “on-guard” against the weather, not just in the spring, but all season long!
HOW TO FEED STARVING MARTINS