A Remarkable and Exciting Success – (not ours :))

Posted in Blog

It worked!  One of PhD candidate Hankyu Kim’s backpack wearing Hermit Wablers flew to Mexico and back bringing data to help answer the puzzle of where they over winter.

Here’s the more complete story:  The heart of Hanku’s research is trying to expand knowledge about the ecology of Hermit Warblers, including answering the previously unanswered question of where they overwinter.  The Hyla Woods team is pleased to help in small ways with the project, including having the breeding habitat in Mt. Richmond Forest serve as a research site.

Because of the bird’s small size, the only suitable tracking device is a tiny “backpack” tracker that records time of sunrise and sunset every day.  From this data, Hankyu is able to analyze where the birds have been.

In the spring of 2019, Hankyu and his helpers worked in seven sites, ranging from Yosemite in the south to Gifford PinchotNational Forest in the north, to catch and band Hermit Warblers.  Tracking “backpacks” were attached to 116 birds.  Knowing that Hermit Warblers are known to be very faithful to finding their way back to breeding habitat, the plan and hope was to recapture them a year later, remove the trackers, and capture data critical to answering the questions.

So, it was with great excitement and anticipation that Hankyu, assisted by his ornithologist wife, Dr. Minsu Jeoung, returned to the forest on May 15th in hopes of reconnecting with one the 11 warblers tagged the previous spring.  Pam and Peter tagged along and watched from a distance.  Nearly invisible mist nets were strung up between poles – a decoy was set up near the net – bird calls played from a recorder – and all anxiously watched and waited.   Calls sounding from the canopy showed that they were nearby.  Hearts raced when several flew into the net, followed by disappointment in seeing that they were not “Hankyu’s birds” returning.

After several hours of unsuccessful effort, Hankyu and Minsu shifted their hunting to a lower area of the forest while Pam and Peter stayed on the hilltop.

Late in the afternoon the thrilling text from Hankyu popped up  – “Got one!”.


Warbler #2620-25758 was captured just 120′ south of where he was banded and tagged the previous June 20th.  Soon Hankyu will download the data and use it to solve the mysteries of where the warblers overwinter.  Data from his earlier recaptures show that these tiny birds make the long round trip to various locations in Mexico.

How remarkable that this bird flew over 4,000 miles to Mexico and back, found its way to this Mt. Richmond ridge top, –  and that Hankyu and Minsu could successfully recapture, unload, and release it!  How’s that for welcome uplift in this time of Covid-19?!

With one of eleven Mt. Richmond birds captured, efforts to catch and unburden the remaining ten continue.  Stay tuned for news reuniting efforts and what they have to teach us.  Hankyu and Minsu continue their recapture work in all of their seven research sites spread through the summer breeding range.

Congratulations to Hankyu on all of his hard and innovative work on this important research project!  As he points out, this was one successful step toward the success of the overall project.

   A well earned, cold brewski to celebrate the success.