Gut Bacterial and Fungal Communities of the Tibetan Eared Pheasant (Crossoptilon harmani) Across a Captive–Temple–Wild Gradient: Implications for Ex Situ Conservation

Gut microbiota influence nutrient acquisition, immune function, and pathogen resistance, yet are rarely considered in ex situ planning. We compared gut bacterial (16S ribosomal RNA; 16S rRNA) and fungal (internal transcribed spacer 1; ITS1) communities of the Tibetan eared pheasant (Crossoptilon harmani), a protected Galliform endemic to the Qinghai–Tibet Plateau, across a management gradient: fully captive (n = 3), wild (n = 7), and free-ranging monastery birds receiving supplementary barley (n = 6); samples were not linked to identified donors, so the kingdoms are compared at group level only. Monastery birds had the numerically highest bacterial Shannon diversity (5.79), above wild (5.54) and captive birds (2.93), although the among-group test was not significant (p = 0.13). Permutational multivariate analysis of variance (PERMANOVA) showed significant bacterial differentiation (Bray–Curtis R2 = 0.309, p = 0.001), driven by the captive group, which showed Lactobacillus dominance (51.4%). Fungal communities also differed significantly (R2 = 0.194, p = 0.008), with no compositional turnover (Jaccard p = 0.447). Birds in natural habitat with supplementary feeding were no more dissimilar from wild birds than wild birds were among themselves, whereas fully captive birds were clearly separated; this pattern warrants testing in replicated, multi-site studies.