EFFECTS OF RADIO-TRANSMITTERS ON FECAL GLUCOCORTICOID LEVELS IN CAPTIVE DICKCISSELS

• Published in: The Condor (Los Angeles, Calif.) Calif.), 2003-11, Vol.105 (4), p.805-810
• Main Authors: Suedkamp Wells, Kimberly M, Washburn, Brian E, Millspaugh, Joshua J, Ryan, Mark R, Hubbard, Michael W
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal behavior; Animal wings; Animal, plant and microbial ecology; Animals; Autoecology; Average linear density; Aves; Biological and medical sciences; Birds; Corticosterone; Dickcissel; fecal glucocorticoids; Feces; Fundamental and applied biological sciences. Psychology; Glucocorticoids; Male animals; Metabolites; Ornithology; passerines; Radio transmitters; SHORT COMMUNICATIONS; Songbirds; Spiza americana; Stress; transmitter; Transmitters; Vertebrata; Vertebrates: general zoology, morphology, phylogeny, systematics, cytogenetics, geographical distribution
• ISSN: 0010-5422; 1938-5129; 2732-4621
• DOI: 10.1650/7174

We determined the effects of a leg-harness transmitter on fecal glucocorticoid levels of wild male Dickcissels (Spiza americana) in captivity. During the postbreeding season of 2001, we captured 10 male Dickcissels in central Missouri and housed them in individual pens of an outdoor aviary. We radio-tagged five birds; the other five were captured and handled, but were not radio-tagged. We collected fecal samples every other day prior to attachment (31 July–21 August) and after attachment (24 August–20 September). Body condition and morphology were similar between control and transmitter-equipped birds. We observed a significant interaction between transmitter attachment and time since attachment. Compared to baseline levels, fecal glucocorticoid metabolites were significantly lower in control (6.1 ± 13.7 ng g−1) than transmitter-equipped (102.3 ± 13.7 ng g−1) birds during the first 24 hr after attachment. Although transmitter-equipped birds showed elevated fecal glucocorticoid levels, the response was acute and returned to baseline levels within 48 hr. Efecto de los Radiotransmisores en los Niveles de Glucocorticoides Fecales en Individuos Cautivos de Spiza americana Resumen. Determinamos los efectos de poner un transmisor con arnés de pata en los niveles de glucocorticoides fecales de machos silvestres de Spiza americana en cautiverio. Durante la temporada post-reproductiva de 2001, capturamos 10 individuos de S. americana en la parte central de Missouri y hospedamos estas aves en jaulas individuales que formaban parte de un aviario al aire libre. Pusimos radio-transmisores en sólo cinco de estos pájaros, los otros cinco sólo fueron capturados y manipulados. Colectamos muestras fecales en días alternados antes (31 julio–21 agosto) y después (24 agosto–20 septiembre) de poner los transmisores. La condición corporal y morfología fueron similares entre individuos con transmisor y individuos control. Observamos una interacción significativa entre poner los transmisores y el tiempo desde que fueron puestos. Comparados con niveles iniciales, hubo diferencias significativas en los metabolitos de los glucocorticoides fecales entre los pájaros control (6.1 ± 13.7 ng g−1) y con transmisores (102.3 ± 13.7 ng g−1) durante las primeras 24 hr despues de ponerlos. Aunque los pájaros con transmisores mostraron niveles elevados de glucocorticoides fecales, la respuesta aguda regresó a niveles iniciales en menos de 48 hr.