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Summary1. The habitat heterogeneity (HHH) and individual adjustment (IAH) hypotheses are commonly proposed to explain a decrease in reproduction rate with increasing population density. Higher numbers of low-quality territories with low reproductive success as density increases lead to a decrease in reproduction under the HHH, while more competition at high density decreases reproduction across all territories under the IAH. 2. We analyse the influence of density and habitat heterogeneity on reproductive success in eight populations of long-lived territorial birds of prey belonging to four species. Sufficient reliability in distinguishing between population-wide, site-specific and individual quality effects on reproduction was granted through the minimal duration of 20 years of all data sets and the ability to control for individual quality in five of them. 3. Density increased in five populations but reproduction did not decrease in these. Territory occupancy as a surrogate of territory quality correlated positively with reproductive success but only significantly so in large data sets with more than 100 territories. 4. Reproductive success was always best explained by measures of territory quality in multivariate models. Direct or delayed (t)1) population density entered very few of the best models. Mixed models controlling for individual quality showed an increasing reproductive performance in older individuals and in those laying earlier, but measures of territory quality were also always retained in the best models. 5. We find strong support for the habitat heterogeneity hypothesis but weak support for the individual adjustment hypothesis. Both individual and site characteristics are crucial for reproductive performance in long-lived birds. Proportional occupancy of territories enables recognition of highquality territories as preferential conservation targets.

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Flight feather moult of White-tailed Eagle (Haliaeetus albicilla) in Schleswig-Holstein, GermanyBetween 1955 and 2000 feathers moulted by White-tailed Eagles were collected systematically in the breeding territories in Schleswig-Holstein, Germany. 581 tail feathers and 382 primaries from a maximum of 22 nest sites (1999) and more than 300 secondaries (8 ! collected between 1960 and 1970) were considered. Moulting process of primaries and secondaries is serially continuous, with several moult waves proceeding simultaneously through separate moult units in each wing. Tail feathers were moulted in sequence of 1-6-3-4-2-5 and showed a predominantly transilient alternation. Although tail and flight leathers could be moulted in any month between April and October, there was a strong tendency for them to be moulted between May and August. The plumage characteristics of 18 dead eagles of known age were also examined. Up to and including the 4th moult (in the 5th calendar year), tail moult was almost complete each year. Adults generally moulted their tail feathers over a 2-year period with an annual moult rate of 53 %. Serial moult of primaries in immature eagles normally was completed within a range of 2 rarely 3 years (annual rate = 49 %). Primary moult in adults took place over 3 (occasionally 4) years. Annual rate for flight feathers of adults (in the 5th moult and later) was 46 %. In Schleswig-Holstein the annual rates for tail and flight feathers were on average higher than those in Finland and Sweden, probably because moulting season there is shorter than it is in Schleswig-Holstein because of the different amplitudes of the photo-period in the two regions on different latitudes. Moult patterns were modelled to demonstrate the influence of breeding status, weather conditions and food availability on annual rate. According to this model females showed a higher annual moult rate of primaries and tail feathers in years without breeding success. Tail and flight feathers were moulted on average 1.5 months later in years with breeding success than in years without. Sex specific differences are seen only in annual moult rate of primaries under specific conditions. Moulting activity is higher in warm and dry summers than in cold and wet summers. This was confirmed by the examination of the plumage of dead birds.

Flight feather moult of White-tailed Eagle (Haliaeetus albicilla)in Schleswig-Holstein, GermanyBetween 1955 and 2000 feathers moulted by White-tailed Eagles were collected systematically in the breeding territories in Schleswig-Holstein, Germany. 581 tail feathers and 382 primaries from a maximum of 22 nest sites (1999) and more than 300 secondaries (81 collected between 1960 and 1970) were considered. Moulting process of primaries and secondaries is serially continuous, with several moult waves proceeding simultaneously through separate moult units in each wing. Tail feathers were moulted in sequence of 1-6-3-4-2-5 and showed a predominantly transilient alternation. Although tail and flight feathers could be moulted in any month between April and October, there was a strong tendency for them to be moulted between May and August. The plumage characteristics of 18 dead eagles of known age were also examined. Up to and including the 4th moult (in the 5th calendar year), tail moult was almost complete each year. Adults generally moulted their tail feathers over a 2-year period with an annual moult rate of 53 %. Serial moult of primaries in immature eagles normally was completed within a range of 2 rarely 3 years (annual rate = 49 %). Primary moult in adults took place over 3 (occasionally 4) years. Annual rate for flight feathers of adults (in the 5th moult and later) was 46 %. In Schleswig-Holstein the annual rates for tail and flight feathers were on average higher than those in Finland and Sweden, probably because moulting season there is shorter than it is in Schleswig-Holstein because of the different amplitudes of the photo-period in the two regions on different latitudes. Moult patterns were modelled to demonstrate the influence of breeding status, weather conditions and food availability on annual rate. According to this model females showed a higher annual moult rate of primaries and tail feathers in years without breeding success. Tail and flight feathers were moulted on average 1.5 months later in years with breeding success than in years without. Sex specific differences are seen only in annual moult rate of primaries under specific conditions. Moulting activity is higher in warm and dry summers than in cold and wet summers. This was confirmed by the examination of the plumage of dead birds.