Estimated Impact of feral house mice on sub-Antarctic invertebrates at Marion Island

✍ Scribed by D. T. Rowe-Rowe; B. Green; J. E. Crafford

• Publisher: Springer
• Year: 1989
• Tongue: English
• Weight: 397 KB
• Volume: 9
• Category: Article
• ISSN: 0722-4060
• DOI: 10.1007/bf00443233

✦ Synopsis

The energy metabolism of feral house mice Mus musculus was established on sub-Antarctic Marion Island, using the doubly-labelled water turnover technique. Mean water influx was 565 ml kg -1 day -1 and mean CO2 production was 5.41 ml g-1 h-l, i.e. 3375 kJ kg-1 day-1. From the energy content of the main items (Lepidoptera larvae, Curculionidae) in the diet of the mice it was estimated that the dry mass of food consumed was 3.5 g mouse -t day -1. The overall impact of mice on invertebrates, based on mean mouse density and the mean percentage invertebrates in the diet, was estimated at 108g ha -1 day -1 or 39.4kg ha -1 y-i (dry mass). Greatest predation pressure was on larvae of the flightless moth Pringleophaga marioni" 65 g ha-1 day-t or 23.7 kg ha -I y-i. Insect biomass is lower on Marion Island than on nearby Prince Edward Island, which is mouse-free. It is suggested that populations of certain insects on Marion Island are depressed by the alien mice.