On The Wings of Whoopers:
Winter Migration of Two Girls Tracking Whooping Cranes in the Southeast
During the past winter, Whooping Crane Winter Research Intern Sloane Wiggers and I spent six weeks on a migration of our own. We used radio telemetry, satellite telemetry, and reports from land managers and the general public to locate Whooping Cranes in the reintroduced eastern migratory population across their winter range. Once we located the cranes, we tracked them from dawn till dusk, collecting behavior and habitat data. This information will allow us to better understand the kinds of places Whooping Cranes spend their winters.
We began our journey shortly after Christmas and made our way to southern Georgia, where Sloane saw her first-ever Whooping Cranes. They are the tallest flying bird, and one of the rarest species in North America, not to mention they are four feet tall and bright white. As you can imagine, our initial reaction was to quickly pull over the van and snap a bunch of pictures of these beautiful creatures. The Whooping Cranes we tracked in Georgia, as well as a group of four sub-adults in Florida, spent a good portion of their day in flooded pastures. They didn’t seem too bothered by wandering cattle, and the open and accessible landscape made it easy for us to see them. When you spend an entire day observing cranes, you quickly get familiar with foraging and preening behaviors, but you can consider yourself lucky when you see territorial or pair formation behaviors. The group of four birds in Florida put on quite the show for Sloane and me, and strengthened pair bonds by dancing (seen here on the left). Whooping Cranes begin nesting as early as age two, but usually not until age 3-5. These cranes were about two years old, and it looked like this group of four was starting to divide into two breeding pairs.
When you tell someone you study Whooping Cranes, a fairly common question they ask is “Do you get to dress up like a crane?” My usual answer to this question is, “No, I study them once they’ve been released into the wild.” However, wearing the crane costume and interacting with juveniles as if you were a crane yourself, is a pretty special experience. A couple of times in the last few years I have been lucky enough to have this opportunity, and this winter it was Sloane’s turn. At St. Mark’s National Wildlife Refuge in Florida, we visited the pen site where the ultralight aircraft had led this year’s cohort of juveniles. At this point in the reintroduction process, they had made it to their final wintering destination, were free to come and go from the pen as they please, but had not yet gotten their permanent bands and transmitters. There were also a few older birds in the area, one of which would begin to lead this group north on their spring migration. On this dreary day, I sat in the blind and recorded one adult’s behaviors and movements, while Sloane helped the caretakers feed the juvenile birds. When she got back to the blind and was cold, wet, and covered in mud, I didn’t expect her excitement. A huge smile stretched across her face as she whispered to me (to not be heard by the cranes), “That was amazing!”
After leaving Florida, we headed north to Wheeler National Wildlife Refuge in Alabama, where the 2011 ultralight-led cohort was released, and where many of them have wintered in subsequent years. The Tennessee River flows through the refuge, and adjacent to its sloughs are flooded agricultural areas managed for waterfowl. There are thousands of ducks, geese, and Sandhill Cranes, that have now been joined by a large group of Whooping Cranes wintering on the refuge. From the refuge’s observation tower, we saw a flock of about 2,000 Sandhill Cranes and 11 Whooping Cranes! The sound alone of all of those birds was incredible, not to mention the sight of cranes in every direction. Most of the cranes we tracked on the refuge were using sloughs and sandbars in the river, flooded fields, and basically anywhere with standing water shallow enough for them to stand in. On one particular day, we were tracking a pair from the 2011 cohort near the refuge. They left the flooded corn field and flew over us back toward the river. When we got close to where they landed, we could hear beeps from their transmitters to our left, but we saw a group of five Whooping Cranes to our right (see photo above)! We quickly looked up their band combinations and scanned through all of the frequencies of working transmitters, to find that this was a group of cranes that was seen in southern Indiana only days before! A cold front had come through the area and while some Whooping Cranes stayed in Indiana, this group travelled south to Alabama, presumably to escape the cold. By the time we left Alabama, we had seen one group of 21 Whooping Cranes on the refuge and about 30 Whoopers in the whole state. For a population of 100 individuals, it was pretty amazing to see such a large portion in one place.
Our migratory path wound north to observe cranes in Tennessee, Kentucky, and Indiana. Other highlights included seeing the female Whooping Crane (W1-06) who had previously wintered at Nemours Wildlife Foundation, with her new mate (1-10) in a snowy corn field in Kentucky (see photo below). It was also incredible to see the range of habitats used by wintering Whooping Cranes in this population. While some migrated as far south as Florida and foraged in brackish marshes of the Gulf coast, others stopped short in snowy agricultural Indiana. We observed flock sizes as small as one individual bird to as large as 21 birds, or one fifth of the total population. These differences are something we plan to investigate further with the data we collected this winter. Overall, we had a very successful field season and located 79 of the 100 Whooping Cranes in this population. This research will help us better understand the winter ecology of these reintroduced Whooping Cranes, which will help future reintroductions be more successful and ultimately will help safeguard this species from extinction.