The prothonotary warbler derives its name from ancient Catholic scribes who were said to wear bright yellow hoods, which these cute little warblers appear to be wearing. As opportunistic as they are brilliant yellow, these eastern warblers are just a little bit lazy as well. If they can find a vacated downy woodpecker nest to claim as their own, they do so willingly. In lieu of finding a ready-made nests, the prothonotary warblers prefer building nests in pre-drilled woodpecker holes or rotted-out branches and stumps. However, I’ve recently learned that they will inhabit man-made nest boxes, too, when strategically under tree canopy near the water.
The Barataria-Terrebonne National Estuary System Program and Foundation (BTNEP), contracted with me to take Natalie Waters, a bird scientist, to install nest boxes in two locations within Terrebonne Estuary System and then check them weekly for acceptance, habitation, and progress. Even though we are not yet to the halfway point of the project, the results so far are very positive, and it looks like we might end up with most of the boxes being adopted.
According to Natalie, these birds migrate in the fall to places south of here, with many flocks ending up in Columbia for the winter. Then ’round about March, along with many other species of migratory birds, they start making their trek north to do their nesting. Fortunately for those of us who live near the cypress swamps, many of these birds choose this area in which to lay their eggs and hatch their young. Those young will most likely return to the same area to lay their eggs and hatch their babies. That is a very good thing!
After the initial installation of boxes in the Mandalay National Wildlife Refuge, we didn’t check or otherwise disturb them for two weeks. When we went back this past week, we were pleased to see that many of the boxes contained nesting material. This far into spring, many of the breeding couples have already hatched and fledged one batch of young. Meaning, this will be their second and final brood of the spring, and it is very encouraging that they have chosen our boxes as the place in which to rear their second families.
Once we performed a visual check of every box and wrote down the information, we sat quietly in my boat within sight of four of the nest boxes and observed. What took place as we watched was a National Geographic moment as the birds began singing out and calling to one another. Soon, a male approached one of the new boxes. First, he flitted around the box, sat on top, and then finally flew in and out several times.
Natalie explained to me that the male bird was inspecting the box. If he liked it, then he would gather some moss (nesting material) and take it into the box. He would then attract the female to see if he could rouse her interest in the box.
Across the way, another pair attracted our attention, with the male flitting around the box to lure the female. Moments later, she showed up to check it out.
She flitted around near the entrance, not certain she wanted to encourage the male by accepting his offer. If she enters the box and likes what she sees, she shows her acceptance by completing the nest building and will build it up to the edge of the entrance hole. This is where she will lay four to six, creamy beige-colored eggs with brown spots and then incubate them for about two weeks. After they hatch, the babies grow so quickly that they will be “fledged” or flying in about 10-11 days.
From now through mid July, our job is to check each of the 40 boxes once a week and record the number of eggs, then the number of live baby birds. At some point, we will try to band the female and the babies, which never harms the birds because their legs get skinnier as they mature. We will then continue to track their weekly growth and the approximate date they fledged.
Locally, these eye-catching gems are called swamp canaries because of their yellow color and a canary-like call they sometimes use. While overall numbers of migratory birds have significantly diminished over the past 50 years due to coastal land loss, it is a wonderful sight to behold these birds in the wild, still clinging to life and migrating through here every spring to procreate. I’m honored to be part of this project, and if by doing this study, we can prolong the existence of prothonotary warbler, then it will have been worth every minute on the water and every ounce of sweat.
For the birds,