Lucy’s Warblers and Nestboxes
Just four inches long and very active, Lucy’s Warbler has been known in the past as the Mesquite Warbler due to their close ties to these trees. Being one of the two cavity-nesting warblers we have in United States, they choose old woodpecker holes as well as peeling bark crevices as their nesting sites. Lucy’s Warblers are in population decline and listed as a Species of Conservation Concern by Arizona Game and Fish – primarily due loss of available nesting sites which occurs most commonly in dense mesquite bosque along major waterways. Even in an urban environment, Lucy’s Warblers seek out mesquite trees, which leads us to our two major projects with these birds. Image by Jeremy Hayes
To learn more about this little warbler click here: allaboutbirds.org/guide/Lucys_Warbler/overview
Unlike many other species that are limited by lack of available nesting sites which have been helped by the creation of appropriate nestboxes, no one yet knows exactly what type of nestbox Lucy’s Warblers would prefer – so much so that even Birds of North America says that they do not use nestboxes. Over the last few years Tucson Audubon has received photos of Lucy’s Warblers nesting in small decorative boxes and various other small cavities. Knowing that there’s an opportunity to make a big conservation for this species, and to increase the state of scientific knowledge on this species, we’ve undertaken a project to better understand Lucy’s Warbler nesting and to develop nestboxes that they’ll readily use.
These study efforts aim to determine the nesting preferences of Lucy’s Warblers with the ultimate goal of increasing Lucy’s Warbler populations by creating functional habitat especially via viable nestboxes in Tucson’s urban areas.
After studying their natural nests we created 8 different designs of nestboxes to suit Lucy’s Warblers and placed them adjacent to each other. We varied their placement on the tree so that the only constant was the style of box used. They were mostly in three sites:
- 7B Ranch on the San Pedro River;
- Along the Santa Cruz River in Tubac;
- Tanque Verde Wash in Tucson.
In 2018 we gave out our nestbox replicates to the general public on the condition that they had mesquite trees in their yards and were willing to monitor the process. Our effort spread as far north as Payson and as far south as Sierra Vista. Our Tucson Meet Your Birds event has helped us reach all ages and all communities. In the very first year we have had great response from the public reporting positive nesting attempts. We expect even bigger numbers next year as more boxes get discovered and identified as suitable nesting cavities by our Lucy’s Warbler friends! This is an on-going project, but we have had a lot successful Lucy’s Warbler broods raised in our boxes so far! Watch for a detailed report coming soon!
Tucson Audubon has set out to study how Lucy’s Warblers use native and non-native types of mesquites as a food source. This is part of our larger effort to determine what Lucy’s Warblers need to successfully nest in urban Tucson which includes our nestbox experiment. We would love your help in watching Lucy’s Warblers forage for insects in locations where both types are present. Tucson Audubon has found a few such locations but you may know of one as well. It only takes a few minutes and we have lots of great information for you including how to tell native mesquites from non-native mesquites. We need your help with this urban conservation! Image by Joan Gellatly
Do you know of a place that should be added to our map of locations that have both native and non-native mesquites? This could be in your own neighborhood! Fill out our survey here: https://goo.gl/forms/fktzqantBlstQNjH3
Tucson Audubon Society
300 E University Blvd. #120 Tucson, AZ 85705
3835 W Hardy Rd.
Tucson, AZ 85742
Paton Center for Hummingbirds
477 Pennsylvania Ave.
Patagonia, AZ 85624