Measuring corticosterone levels is the standard method to assess stress levels in birds. However, this hormone is involved in multiple other physiological processes during migration making its interpretation in the context of stress difficult. Therefore, in our study published in the Journal of Ornithology, we investigated whether an immunological tool called leukocyte coping capacity (LCC) provides useful complementary information on the stress response in migratory Garden Warblers caught at their stopover site on Ponza Island.
Our results show that LCC significantly decreased during the acute stress response, which implies high-stress levels and a diminished capacity to recover after a stressful event. This outcome further confirms that the LCC method is a useful tool to extend our understanding of stress and the ability of migrating birds to cope with it.
If you want to learn more about the Leukocyte coping capacity and how it relates to the classical corticosterone stress protocol and the energetic condition of these migratory birds, you can access the paper following this link.
Nikolaus Huber, Virginie Canoine, Jessica S. Cornils, Ivan Maggini, Massimiliano Cardinale, Thomas Ruf & Leonida Fusani. Leukocyte coping capacity as a complementary stress metric in migrating birds. J Ornithol (2020). https://doi.org/10.1007/s10336-020-01774-9
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I read your article that’s full of knowledge we consider just human stress level and literally the first time I just realize that birds also have stress level.