Thanks for the update, Eva!!!
Whooping Crane Update
by Eva Szyszkoski of the International Crane Foundation
One of the Whooping Cranes most loveable traits is that they mate for life. But do they really? Do we just assume they mate for life because most of them do? If they mate for life, how can we explain the behaviors of two of our Eastern Migratory Population females, numbers 13-03 and 19-05?
Spring of 2010: A summer fling
May 16th started out normally enough and by mid-day I was tracking birds on the southern portion of the Necedah National Wildlife Refuge. As I was arriving at Site 5, one of the ultra-light training sites, a single Whooping Crane was flying up from the south. It landed in the marsh just north of the road I was on it was female #13-03. Her mate, #18-03, was still off to the south. Pair #’s 13-03 and 18-03 had not only nested in 2010, but also during the previous two springs.
As I sat there waiting for my for my GPS to average out so I could get my data point, another lone crane flew in from the south to land by #13-03. Initially I thought it was her mate #18-03, but soon I realized it was single male #9-05 instead. Upon landing, #9-05 unison called alone and began parade walking (a kind of threat) up and down the dike while #13-03 ignored him and began foraging in the marsh. I could hear her mate calling from his southerly location, but #13-03 was oblivious to his distress. Eventually #9-05 gave up his threats and began to make pre-copulatory calls, a low purring common before mating. Still I didn’t think much of it. Single males on the refuge were always trying to get female companions, even if they were already paired. It wasn’t until five minutes later when the shocking part began…#13-03 began pre-copulatory calling to #9-05! I was amazed. To the south, #18-03 continued his alarm calling, lone unison calling and ‘where are you’ noises.
After about two minutes of pre-cop calling to each other, #13-03 opened her wings and turned her back to #9-05. I couldn’t believe what I was seeing. She was soliciting him, the last action before mating! 9-05 began to slowly walking towards her, both still pre-cop calling, but instead of mating with her, he walked right by. 13-03 closed her wings but they continued to call to each other for another 15 minutes before settling down to forage together. #18-03 was now making desperate calls, but still #13-03 ignored him. Throughout the rest of the summer, #13-03 would only occasionally return to #18-03, but ultimately she chose to stay with him on migration and over the winter. Will she choose to stay with him through this nesting season? We’ll have to wait and see!
Winter 2010/2011: Recruiting from the outside
Pair #’s 8-04 and 19-05 had nested for previous three springs before this winter arrived. Everything was normal as they reached their now-normal wintering grounds at the Paynes Prairie Preserve State Park in Florida. Male #8-04’s transmitter battery was dead and observations of the cranes in this large marsh with limited public access was difficult, so mainly we relied on #19-05’s signal to let us know that all was well. Besides the seven migratory Whooping Cranes spending the winter here, there were also two Florida Non-Migratory birds, a male and a female (not paired). The winter passed by with no indication that something amazing was going on out on the prairie.
On March 3rd, #8-04 was reported alone at the pair’s only consistent migration stopover location in Indiana (his ID wasn’t confirmed until March 6th). Immediately I, and others, began thinking that something bad had happened to his mate. I dreaded having to try to find her body. Paynes Prairie is packed with alligators of all sizes, hiding in the marsh vegetation and lounging on the banks. Not somewhere you would want to go if you could avoid it; and this was all dependent on if and how I would be allowed on the marsh.
I headed up to Paynes Prairie to listen for #19-05’s signal (you can almost always tell is a crane is dead of not just by signal strength and orientation of a handheld antenna). As I drove past the prairie on Highway 441, I heard #19-05’s signal loud and clear. Weird. I stopped at both the little observation platform off of the highway and at the observation tower in the park itself and listened. The signal was still strong and clear. There was no way that it was a signal of a dead, possibly submerged transmitter. No way. But then what was going on?
That day, we received a report through the online Whooping Crane observation reporting website of two birds seen off of the public trail, leg bands matching #19-05 and nearly eight year old non-migratory male #1343. Clearly #19-05 had ditched #8-04 for this new male and a non-migratory male at that! This was a first. We’ve had limited migratory and non-migratory interactions in the past, but they were never very strong. For the next few weeks, #19-05 remained at Paynes Prairie with #1343. The question we were now all asking was would the pull of migration take her back north and possibly back to her previous mate or would #1343 entice her to stay in Florida and nest with him? What actually happened was unexpected.
On April 5th, I checked Paynes Prairie one last time. #19-05 was gone. I figured she chose migration over the male. On April 6th, I received a report and photo of two birds in central Indiana. I scrolled down the email until the photo appeared and was speechless. #19-05 was migrating alright, but she was taking (previously) non-migratory male #1343 back with her! It will be interesting to see what will happen if she wants her old territory back, a territory that #8-04 is still on with young female #8-09 (who he has apparently wooed). The drama is sure to continue…
(photo by Billie Dodd, Indiana)
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