A Good Year for Wild-Hatched Whooping Cranes

The Louisiana Non-migratory Population have reported that they are having a banner year. Five wild-hatched chicks have fledged, including a set of twins. Three of the pairs are first-time nesters, and two of the males are just 2 years old. (Here’s a link to their press release)

There are four wild-hatched chicks at Necedah this year that should be fledging very soon (If they haven’t already) and two more that are referred to as off-refuge – These two off-refuge cranes have been confirmed as fledged.

Six fledged chicks is a record for the EMP and, maybe some indication that they are finally figuring out how to deal with that challenging environment. We know that black flies at Necedah cause nest abandonment and pre-fledge chick mortality has been very high there so far, but maybe this is the turning point. 

Defending chicks and other parenting skills are partly instinctive and partly learned. As an example, there was a pair of Whooping cranes in the Florida non-migratory flock that lost their chick each year to a Bald eagle. Eventually, they figured out a defense strategy and during the last attack, the eagle had to be rescued before the cranes killed it.

It is interesting to note that all of these cranes, the two that figured out how to deal with the eagle, the five successful pairs in Louisiana and the six, hopefully soon to be successful pairs at Necedah – were all costume-reared. 

The five surviving chicks in Louisiana is exciting news especially the part about 2 year old males. If it continues, that flock could reach its self-sustaining status in record time. 

With promising results in Louisiana and, up until now, poor reproduction success at Necedah, its easy to see why the Recovery Team might shift their focus. They have directed that the majority of chicks available for release be assigned to the LNMP while WCEP gets just enough to keep the partners busy and to test an already disproved release method.

But that strategy ignores the value of the 100 or so birds in the EMP. In fact, with restricted releases, even the great results achieved this year at Necedah won’t last. Natural attrition will reduce the number of breeding pairs there and it won’t be long before fewer breeders will be available to learn predator defense techniques. 

It is becoming obvious that the rearing method is not the issue at Necedah. Black flies causing nest abandonment and chicks that don’t survive long enough to learn to fly, point directly at environmental issues. Even the Sandhills can’t make it work there.

The Recovery Team should take this year’s success as an opportunity to refocus their efforts. The Service should, once and for all, find out what is killing the twenty or so chicks that hatch each year at Necedah and finally determine if something can be done to mitigate the problem. 

Parent-rearing should be dropped for the costume-rearing method, which can provide more chicks to be released each year. Parent-rearing takes adults out of production at the captive breeding centers. Rather than producing more eggs to be costume-reared/released, the adult birds spend their time raising one or two chicks. Plus there are a limited number of adult Whooping crane pairs on the landscape outside of the Necedah area to release the parent-reared chicks with so most end up migrating south with Sandhill cranes. 

Dr. Brad Strobel of Necedah uses an innovative technique for circumventing the black fly issue. He uses temperature days to anticipate the bloom of those biting insects. Just prior to the peak, he collects eggs from the pairs that would normally abandon their nest when the flies attack. Those egg are incubated at one or more of the captive centers and eventually the chicks are reintroduced. When Whooping cranes lose their eggs early on in the process, they will often start a new nest and lay more eggs. It’s referred to as double clutching and generally occurs after the relatively short black flies season. Those second nests are more successful. 

Initially, the eggs collected from the “first nesters” were hatched at Patuxent and returned to Necedah as chicks along with some captive produced chicks. When the Louisiana project began, the Recovery Team made WCEP responsible for all of its own eggs. How many we got depended on how many were harvested just prior to when the black flies bloomed. All of the captive produced chicks went to Louisiana.  

Then the strategy changed. In 2018, the EMP was limited to ten chicks, no matter how many were harvested from Necedah and all were to be parent-reared. 

At the last count, four parent-reared chicks will be released this fall. The two chicks fathered by 16-11 at White Oak in Florida are scheduled to be released at Horicon this week. They are also included in the count of parent-reared releases this year.

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4 Comments

  1. Meg August 22, 2018 11:36 am

    How are we to receive up dates over the next years if Operation Migration is not supplying the information?

  2. Lindsay August 22, 2018 10:19 am

    What an infuriating set of decisions that are being made. It must be so frustrating and heartbreaking to not be able to do what’s best for this population. Is there anything that can be done?!

  3. RadAudit1 August 22, 2018 9:22 am

    It seems that unless the situation changes, the EMP will eventually disappear. It’s really a shame.

  4. Dick Brooks August 22, 2018 8:59 am

    Thank you for some very good news and some not so much. I understand with the closing of Patuxent why there are less captive reared eggs available this year but why are there not ten chicks available for release into the EMP this year?