Developing New Methods to Quantify Stress in Wildlife Using Liquid Chromatography Tandem Mass Spectrometry

Stress levels in wildlife species are an accurate indicator of an animal’s well-being and can reflect decreases in habitat quality. Stress levels can be measured by the presence of the stress response hormones cortisol, cortisone, and corticosterone. Analysis of these stress hormones in fecal samples has been widely used because feces can be easily obtained and non-invasively collected in the field. Methods of detecting stress levels from fecal samples of wildlife species are currently limited to enzyme immunoassay testing. This method uses antibodies to bind to target stress hormones. However, immunoassay testing can be time consuming and very expensive ² . We propose that Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS) offers a new method to quantify levels of the stress hormones from fecal samples that is less expensive and time consuming than traditional immunoassays ¹ . As part of the Idaho Science Talent Expansion Program (STEP), we are developing a simple, accurate, and relatively inexpensive method to detect stress hormones in fecal samples from free-ranging pygmy rabbits (Brachylagus idahoensis) and sage grouse (Centrocercus urophasianus) using LC-MS/MS.