The effect of upland afforestation on the ecology of lagomorphs with different feeding strategies

• Main Author: Hulbert, I. A. R.
• Published: University of Aberdeen 1993
• Subjects: 591.7
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.592597

A herbivore's feeding strategy is a likely determinant of its response to a change in land use. This study investigates the effect that upland afforestation has on two herbivores with different feeding strategies; mountain hares which are summer grazers that switch to browse in winter, and rabbits which eat mostly grasses throughout the year. The mean home-range size (determined by radio-telemetry) of females within a moorland/young forest/improved pasture mosaic was 11.7ha. for hares and 2.8ha. for rabbits. For both species range size varied with habitat and for hares varied seasonally. Throughout the year, hares preferred the forest and pasture habitats relative to availability although use of the forest increased in winter. By contrast, in each season rabbits utilised the available habitats in proportion to their availability. Counts of faecal pellets indicated that utilisation by both species declined as a forest matures although hare populations persist in mature pine plantations with an abundant ground flora. Faecal n-alkane analysis revealed that the diet of individually radio-tracked female hares in winter is dominated by <i>Calluna vulgaris</i> but in summer is dominated by grasses. The proportion of <i>Calluna</i> in the diet was generally lowest for those hares inhabiting woodlands. Throughout the year the proportion of grasses in the diet of radio-tracked hares was greater than the proportion available within their feeding range. Mountain hare leverets restricted to woodland during their growth period were heavier in autumn than those leverets restricted to moorland. Grasses dominated in the diet of rabbits although rabbits inhabiting the forest had a significantly greater proportion of dietary <i>Calluna</i> than those on the improved pasture. Body size did not vary between habitats. The prevalence and intensity of helminths in both species was not affected by habitat. In conclusion mountain hares are more adaptable than rabbits in their use of habitats, a behavioural tactic underpinned by their flexible feeding strategy which allows them to be more responsive to land use change.