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Quantitative field data on sexual dimorphism is scant for most bird species. In this first field study of a western Himalayan population of Green-backed Tits (Parus monticolus), we demonstrate that breast stripe width is a dimorphic trait that is a reliable measure to sex this species in the wild. Based on our ability to sex the birds in hand, we describe the sexual dimorphism in eco-morphological variables in our study population. Sexual dimorphism in beak morphology changed from winter to summer due to males having shorter beaks (4.5%) in summer; however, there was little change in female beak measurements. Our study on this Himalayan congener of a widely studied European species can be used to inform studies of the evolutionary ecology of morphological traits in closely-related species inhabiting vastly different habitats.

Despite its prevalence across bird taxa, avian vocal mimicry remains a poorly studied field of animal behaviour. In order to advance our understanding of the function of avian vocal mimicry, the field requires that the range of vocal mimicry in birds is described. The Tawny Lark (or Sykes's Lark, Galerida deva) is endemic to central and western India. Recent work on other Galeridalarks has found that the mimetic vocalisations match the biodiversity of their acoustic environment, thereby conferring a significant novel function in study of individual mimetic variation linked to biodiversity. Here, we provide a detailed account of the variety of mimetic sounds produced by the Tawny Lark. We also describe acoustic and peer-based analyses that gauge the accuracy of the mimicry. By providing a detailed description of mimicry, we provide a basis for future study of the function of mimicry in this species.