Songbird Singing a Different Tune
It is spring at our San Clemente loggerhead shrike breeding facility on the U.S. Navy’s San Clemente Island (SCI). This is the 22nd breeding season for the facility, and 15th for me, and things have changed dramatically on SCI since that first season.
In 1998, the year before I joined the project, there were only 14 shrikes in the wild. My first year coincided with a major revision on our release methods led by the Institute for Wildlife Studies in collaboration with all of the Shrike Working Group members, including the U.S. Navy, the U.S. Fish and Wildlife Service, PRBO Conservation Science and the San Diego Zoo.
These changes led to the first successful recruitment of shrikes released from our facility into the wild breeding population. Shrikes that hatched in our facility have survived and bred in the wild, and in 2009 the population reached a high of 179 breeding adults.
Though we have released many successful shrikes, there is one particularly special shrike that I must share with you. Studbook 424 male, who we call Trampas, hatched in April 2001 and was reared by his parents in our breeding complex, was released as an independent juvenile in July 2001.
Within just a few weeks, he established a territory that encompassed our offices at Stone Station, about a mile from his release site and three miles from where he had been hatched. Trampas is still here in 2013!
Trampas, who turns 12 in April, is the longest-lived shrike on record in the wild, and he is the most successful breeder, as well. Over ten breeding seasons, he has had several mates, including one very long relationship, 2002 to 2009, with Studbook 592 female, who we called Mrs. Trampas.
He has hatched 81 chicks, and 14 of these chicks have survived and bred. By our current count, 598 shrike chicks that have hatched on SCI are descendants of Trampas – 81 chicks, 121 grand chicks, 120 great grand chicks, 188 great great grand chicks, 97 great great great grand chicks, and 17 great great great great grand chicks!
Trampas is part of our daily life at Stone Station. He is usually asleep when we arrive at work in the dark, but we soon hear his song as the sun rises. He usually nests quite close to our buildings, and sometimes even inside a storage building, which means we stay out while shrikes take over.
His chicks fledge near us as well, and we put up warning signs to alert visitors to watch out for juveniles perched on their cars, or zooming through the area. As chicks get older, male shrikes are the most active parent, females drop out near the time the chicks fledge, to go and lay a second clutch. The male then takes over feeding all of the fledglings and the female, too, as she incubates the new clutch. This means we get to watch Trampas as he gets very busy with his growing brood, as we get busy with our daily chores.
We don’t know how many more breeding seasons are left for our favorite shrike, Trampas, and we dread the day when we no longer hear and see him about the place. But, he has done a fabulous job in aiding the recovery of this once critically endangered subspecies.
Susan Farabaugh, Manager, San Clemente Loggerhead Shrike Project