Introgression of exotic Cervus (nippon and canadensis) into red deer (Cervus elaphus) populations in Scotland and the English Lake District

A new area of extensive sika deer introgression into red deer populations has been identified in South Kintyre, Scotland. This finding challenges previous assumptions about limited hybridization between exotic Japanese sika (Cervus nippon) and North American wapiti (C. canadensis) with native red deer (C. elaphus). The study used 22 microsatellite loci and a diagnostic mitochondrial marker to analyze 2,943 deer samples from Scotland and the English Lake District, revealing scattered evidence of past hybridization and backcrossing in Northern Scotland, including individuals with mixed ancestry. While sika alleles were detected in South Kintyre and traces in the Lake District, no introgression was found in Central Highlands or Hebridean red deer refugia. The research suggests that while assortative mating persists, further spread of sika alleles into red deer populations remains a concern.

Smith, S. L., Senn, H. V., Pérez‐Espona, S., Wyman, M. T., Heap, E., & Pemberton, J. M. (2018). Introgression of exotic Cervus (nippon and canadensis) into red deer (Cervus elaphus) populations in Scotland and the English Lake District. Ecology and Evolution, 8(4), 2122–2134. Portico. https://doi.org/10.1002/ece3.3767