Methods for the identification of farm escapees in feral mink (Neovison vison) populations

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review

  • Sussie Pagh, Department of Chemistry and Bioscience-Section of Biology and Environmental Science, Aalborg University, Aalborg, Denmark.
  • ,
  • Cino Pertoldi, Department of Chemistry and Bioscience-Section of Biology and Environmental Science, Aalborg University, Aalborg, Denmark., Aalborg Zoo/Aalborg University, Mølleparkvej 63, 9000, Aalborg, Denmark., Denmark
  • Heidi Huus Petersen, Technical University of Denmark
  • ,
  • Trine Hammer Jensen, Department of Chemistry and Bioscience-Section of Biology and Environmental Science, Aalborg University, Aalborg, Denmark., Aalborg Zoo/Aalborg University, Mølleparkvej 63, 9000, Aalborg, Denmark.
  • ,
  • Mette Sif Hansen, Technical University of Denmark
  • ,
  • Sussi Madsen
  • David Chr Evar Kraft
  • Niels Iversen, Department of Chemistry and Bioscience-Section of Biology and Environmental Science, Aalborg University, Aalborg, Denmark.
  • ,
  • Peter Roslev, Department of Chemistry and Bioscience-Section of Biology and Environmental Science, Aalborg University, Aalborg, Denmark.
  • ,
  • Mariann Chriel, Technical University of Denmark

In Denmark, American mink (Neovison vison) have been bred for their fur since the mid-1920s. Mink escaping from farms may supply the feral population. Often, it is of biological and management interest to separate the population of feral mink (i.e. mink caught in the wild) in two groups: 1) mink born on farms i.e., escapees, and 2) mink born in the wild. In this study, two methods were used for separating feral mink into the two groups: a) Comparison of body length of farmed mink and feral mink, and b) Presence of a biomarker (tetracycline: an oral antibiotic used on mink farms). A total of 367 wild caught mink (from the mainland of Denmark and the island of Bornholm), and 147 mink from farms, collected during the period 2014-2018, were used for the analysis of body length. For the testing of tetracycline (TC) as a biomarker, 78 mink from farms where there was knowledge about TC treatment (with or without) were examined for fluorescent markings in the canine teeth. Results from both univariate analyses and Gaussian mixture model analysis demonstrated clear divisions between the mean body length (mean ± S.E., range) of farmed males (52.1 cm ± 0.4, 48-68) and farmed females (mean 44.0 ± 0.2, 40-50), and between farmed mink and wild caught mink. Mixture analysis identified two groups within each sex of the wild caught mink, one assigned to farmed mink (born in captivity) and another group of smaller mink suspected of being born in the wild. On Bornholm, the mean (±SD, range) length of males born in the wild was 43.7cm (± 0.3, 36-57) and for females 37.5cm (± 0.3, 32-45). The mean length (±SD, range) of males born in the wild in the mainland of Denmark was 42.5cm (± 2.3, 36-46) and for females 36.1cm (± 1.0, 34-37). Among the feral mink from mainland Denmark, 28.4% of males and 21.6% of females were identified as escapees, while 0% of the males and 1% of the females were identified as escapees among the wild caught mink on Bornholm. Eight percent of mink from farms using tetracycline were false negatives, while no false positives were found among mink from farms not using TC. TC fluorescence was found in five of 217 mink caught in the wild equivalent to 22% escapees in mainland Denmark. No TC markings were found in mink caught in the wild on Bornholm. In conclusion, both methods a) the body length of mink, and b) fluorescent biomarkers in canine teeth are considered as useful tools to identifing mink that have escaped from farms.

Original languageEnglish
Article number0224559
JournalPLOS ONE
Volume14
Issue11
Number of pages14
ISSN1932-6203
DOIs
Publication statusPublished - 11 Nov 2019

    Research areas

  • AMERICAN MINK, BODY-SIZE, CONSEQUENCES, DIMORPHISM, FOX VULPES-VULPES, IMPACTS, INCREASE, MUSTELA-VISON, SPAIN, VACCINATION

See relations at Aarhus University Citationformats

ID: 172994198