This article was written by Lisa Mills, a technician in the Stoddard Bird Lab. Lisa has a background in avian research, which has taken her across the Americas to study species such as the Scarlet Macaw, Pinyon Jay, and now Red-cockaded Woodpecker at Tall Timbers. She enjoys exploring new outdoor spaces and finding the next cool bird to add to her eBird profile.
Now that summer is on its way out, most nestling birds have flown the nest and are learning to survive in the wild, as are the newest group of cross-foster chicks from the spring 2024 Red-cockaded Woodpecker season.
The Red-cockaded Woodpecker (RCW) is listed as federally endangered and has suffered greatly from historic habitat loss and fragmentation. These birds need large areas of mature pinewoods with frequently burned understory and suitable cavity trees to thrive. Most populations of RCWs, however, are separated by miles of unsuitable habitat such as roads, human development, and thick hardwood forests. This leaves populations isolated, makes it extremely hard for juvenile birds to establish their own territory, and creates an inbreeding risk for these small populations of woodpecker.
These two chicks are being swapped between two properties, Livingston Place and Avalon, a distance of about 20 miles, about 10 times further than these woodpeckers would disperse otherwise.
This is where chick cross-fostering comes in. The idea is that translocating nestling birds to a new territory will both increase genetic diversity of the species, and make it easier for these fostered birds to integrate into the social structure of their new home. Translocation is of particular importance in areas such as South Florida where there are many small and fragmented populations, and this work is critical to creating a more robust population of woodpeckers across the landscape.
Tall Timbers monitors several populations of RCW in the Red Hills region of Northern Florida and Southern Georgia. With collaboration from Georgia DNR, the Stoddard Bird Lab successfully translocated 5 pairs of RCW nestlings in spring 2024, 10 birds in total, to new homes where they will help strengthen the next generation of woodpeckers.
Nestling RCWs between 6-10 days old are selected as potential candidates for cross-fostering. When 2 chicks from different populations are within a similar age and weight range (usually within 1 gram of each other), biologists can successfully complete a chick swap. This involves 2 groups of biologists climbing the nest trees at the same time, taking one chick out of the cavities to band them with unique color ID, then meeting halfway between populations to exchange the precious cargo. The swapped chicks are then taken to their new territory and placed in the nest cavity, where they can grow up completely integrated into their new home.
Once in the new cavity, the parent birds have been observed feeding the new chicks just like they would their own. There seems to be a 100% success rate of parent RCWs accepting new chicks into the nest, and almost all of these chicks have been confirmed fledging from the nest.
This method of translocating RCWs into new territories is easier on the birds than translocating adults or juveniles, where they have to fight for a breeding position and navigate the social structures already in place.
The foster chick from Livingston Place shows off his color bands very nicely. Male juvenile RCWs will have a small red spot on the top of their head, so we know this one is a male and has survived close to fledging.
Translocation success for juvenile RCWs is only 60% at best, whereas translocating nestlings is more successful, more cost-effective, and easier on the birds and biologists involved.
While the methods for translocating nestling RCWs has been considered a success, the ultimate goal for these foster chicks is to obtain a breeding position and increase genetic diversity of the population. More research is needed as to whether or not these foster chicks are actually surviving to breed, and if their chicks will help increase fitness of the species.
A special thanks to Georgia DNR’s Joe Burnham and Christina Lokey for working in close collaboration with Tall Timbers to make these translocations happen, and to Tall Timbers biologist Rob Meyer for teaching me how to complete this important work. This project provided a great opportunity for me to contribute to hands-on conservation of an important and charismatic species.
