Auteur(s): Cormier, Jean-Paul, Fustec, Joelle, Pithon, Josephine, Choisy, Patrice
Bron: BIRD STUDY, Volume 55, Number 1, 1 March 2008 , pp. 86-93(8)
Abstract:
Aims To investigate relationships between vegetation structure and nest selection by Montagu's and Hen Harriers.
Methods We defined three vegetation strata: upper, intermediate and lower. Height and cover of plant species in each stratum were recorded in a 9-m2 area centred on nests or unused random points. Statistical analysis was performed to reveal predictors for classifying plots (i) with a Montagu's Harrier nest, (ii) with a Hen Harrier nest and (iii) without a nest.
Results Montagu's Harriers selected places where tree cover was less than 25%, the maximum height of the upper stratum was 1.87 m, and the cover of the intermediate stratum was greater than 75%. Hen Harriers nested either in plots where the upper stratum was higher than 1.87 m, or where tree coverage was greater than 25%.
Conclusions To encourage the breeding of Montagu's Harriers, the planting of pine should be avoided and the heath should be rejuvenated before it reaches 1.80 m in height. For Hen Harriers, certain plots of heath higher than 2 m should be kept. In agricultural landscapes, patches of managed shrubland or heathland could help conservation of both species.
Bron: BIRD STUDY, Volume 55, Number 1, 1 March 2008 , pp. 86-93(8)
Abstract:
Aims To investigate relationships between vegetation structure and nest selection by Montagu's and Hen Harriers.
Methods We defined three vegetation strata: upper, intermediate and lower. Height and cover of plant species in each stratum were recorded in a 9-m2 area centred on nests or unused random points. Statistical analysis was performed to reveal predictors for classifying plots (i) with a Montagu's Harrier nest, (ii) with a Hen Harrier nest and (iii) without a nest.
Results Montagu's Harriers selected places where tree cover was less than 25%, the maximum height of the upper stratum was 1.87 m, and the cover of the intermediate stratum was greater than 75%. Hen Harriers nested either in plots where the upper stratum was higher than 1.87 m, or where tree coverage was greater than 25%.
Conclusions To encourage the breeding of Montagu's Harriers, the planting of pine should be avoided and the heath should be rejuvenated before it reaches 1.80 m in height. For Hen Harriers, certain plots of heath higher than 2 m should be kept. In agricultural landscapes, patches of managed shrubland or heathland could help conservation of both species.
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