Every two to three days Nancy has been monitoring the Purple Martin nests. The colony has done reasonably well – certainly better than last year in terms of fledging percentage (I’ll report on the final numbers when everything is done). We have been banding the nestlings as we go and as they reach an appropriate age/size. We had just one last nest to do consisting of 4 young. The fact that this nesting was so much later than the rest of the others suggests that it may have been the work of young birds that are just learning how to go about parenting (but this is just conjecture as we don’t have the means to safely capture and check adults).
When Nancy opened the nest box we could see right away that things were not right. The birds did not respond to this change at all. They appeared weak and lethargic and….one had died. This latter bird was much smaller than its siblings and emaciated: it had starved. When we weighed the living nestlings we found that they weighed about a third less than other nestlings we’d weighed of a similar age – these birds were starving too. We could let nature take its course or….try to do something about it. We chose the latter course – Purple Martins are on a precipitous decline, every one counts!
While Nancy rushed off to buy some mealworms I got Sandy (Red’s “mother” – see blog for July 16th and “Red’s First Bath) involved. We left the healthiest (i.e., heaviest) bird in the nestbox as sort of a control and took the other two to the banding lab. Nancy and Sandy plied them with mealworms and cut up earth worms (“wormy nuggets”) but with little success. They seemed too lethargic or, more likely, weak. But then Sandy had the great idea of playing the Purple Martin song on her iPhone app. The sound of the adults perked the little guys up and they began to feed, slowly but steadily (the girls still had to jam the food into their mouths – they weren’t actively opening their mouths to get the food). They would take a mealworm or nugget or a couple and then doze off. After awhile they began to feed more actively and show more energy – a good sign.
Nancy took them home last night and reported: “The birds are doing great!! When I play the PUMA call, both of them stretch up with mouths WIDE open eating all of the worms.”
And this morning: “Eating with gusto this morning!”
We will check the nestbox this afternoon to see how the “control” nestling is doing and to weigh all 3 youngsters. If the nestbox bird is losing weight we will have to decide whether to take it with us for supplemental feeding. We will also have to figure out how to return the rescued birds to the wild. Perhaps we will be able to slip them into another nest with successful nestlings. Leaving the nest to venture out into the big world is a process involving learning from adults – without it all this work may be in vain.