Nick Fox BSc, CEd, PhD, RF, Project leader
Barbro Fox, BEd, Research assistant,
Tom Bailey, Research assistant
The Peregrine Fund, Inc. Laboratory of Ornithology, Cornell University, Ithaca, New York 14850, USA financed this research.
Summary of the article:
Fifty-five km2 of the Black River Gorges area of Mauritius were surveyed for plant cover and contained 160 ha (3.2%) open ground, 985 ha (19.6%) acacia scrub, 705 ha (14%) exotic forest, 431 ha (8.6%) scrub, 846 ha (16.8%) semi-scrub, 562 ha (11.7%) degraded forest, 1286 ha (25.6%) full indigenous forest and 53 ha (1.1%) rocks. Only 150-200 ha (3.5%) of the area is considered to hold regenerating indigenous forest, and the possible reasons for the deterioration of forest in the Gorges are examined.
Locations of 16 resident pairs of wild kestrels are documented together with the production of at least 11 young. The wild population is estimated at about 50 individuals. Reproductive success was 2.0 young per pair for 6 successful pairs of 8 pairs studied in some detail. Parameters affecting nest site selection, predation on, and distribution of kestrels are examined. Seven-time budgets of radiotracked kestrels are tabled giving details of nest-related activities, incubation, territorial and predatory activities in relation to habitat zones, and segmented by hour block. Incubation patches of 12 kestrels are illustrated. Hunting range sizes varied from 44.6 to 74.5 ha—mean 59.8 ha (n=7). Hunting methods were defined, and 63 attacks by wild kestrels analysed. Twenty-one prey items identified in these attacks were compared with 103 prey items identified in nest deliveries. Relationships in hunting success, hunting intensity, and family needs are examined briefly. Seventeen tables and 44 maps or figures are included.