Pertti Saurola

University of Helsinki | HY · Finnish Museum of Natural History

Time trends and regional differences of polychlorinated dibenzo-p-dioxins and -furans (PCDD/Fs), polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), DDTs, polybrominated biphenyls (PBBs) and polybrominated diphenylethers (BDEs) were studied in unhatched osprey eggs collected by bird ringers in 1972–2017 from four areas in Finland...

Capsule: Voles are the main prey of the Ural Owl Strix uralensis in Europe, with larger prey and higher prey diversity being positively associated with owl breeding performance. Aims: To assess the breeding diet and its influence on the breeding performance of the Ural Owl across a north–south gradient of its European range using nest box monitorin...

Capsule: Monitoring of demographic parameters by volunteer ringers provides insight into the factors driving population changes in owls. Aims: To assess the value of national ringing, recapture and recovery data from volunteers to understand population dynamics. Methods: We analysed 49 years of ringing, recapture and recovery data from throughout F...

The expansion of wind energy over large areas may be accompanied by major conflicts with birds, including birds of prey. Hence, it is desirable that the space use of species known to be vulnerable to wind energy be assessed in light of current and future developments. Here, we report on the large-scale dispersal movements of pre-breeding white-tail...

Capsule: A questionnaire identified 1196 raptor monitoring species schemes within 236 monitoring programmes across 37 countries. Aims: To assess the level of monitoring of status/trends of raptors across Europe, to produce a web-based inventory of activities. Methods: A questionnaire promoted by voluntary national coordinators assessed monitoring c...

Pandion haliaetus en El Oeste Paleártico: Tamaño de La Población Reproductiva Y Tendencias A Comienzos Del Siglo XXI El número de parejas nidificantes de Pandion haliaetus registradas en Europa, el norte de África y Oriente Medio ha alcanzado entre 9500 y 11 500 a comienzos del siglo XXI. Comparado con los números de la década de 1980 (ca. 5500 par...

Upon leaving their natal area, dispersers are confronted with unknown terrains. Species-specific perceptual ranges (i.e. the maximum distance from which an individual can perceive landscape features) play a crucial role in spatial movement decisions during such wanderings. In nocturnal animals that rely on vision, perceptual range is dramatically e...

The distribution of the Ural Owl (Strix uralensis) in Europe shrank dramatically at the end of the nineteenth century, largely through direct persecution. No genetic information on this species is available that could provide a basis for ongoing conservation and breeding programs. Here, we genetically analyzed wild and captive populations of Europe...

Forest age structure has become younger and the amount of old forest has decreased due to intensive forestry in Northern Europe. Consequently, large forest‐dwelling hawks may lack nest sites as they need large trees to support their nests. Construction of artificial nests has been a globally adopted conservation measure to provide nest sites for se...

Despite the key role of raptors (including birds of prey Falconiformes and owls Strigiformes) in ecosystems and their sensitivity to environmental change, a well coordinated, Europe-wide monitoring of raptors is lacking. EURAPMON, a Research Networking Programme of the European Science Foundation, was launched with the aim of establishing a sustain...

In Finland, population monitoring for both diurnal and nocturnal raptors has been almost entirely based on fieldwork carried out by voluntary raptor ringers. Responsible organisations include the Finnish Museum of Natural History, with economic support for administration from the Ministry of Environment, “Metsahallitus” (former National Board of Fo...

Contemporary research has documented a large number of shifts in spring phenology and changes in distribution range although the average spring temperatures have increased by only 0.3-0.6 °C over the past 100 years. Generally, earlier breeding birds have larger clutch sizes, and the advancing spring could thus potentially increase breeding success....

The ongoing climate change has improved our understanding of how climate affects the reproduction of animals. However, the interaction between food availability and climate on breeding has rarely been examined. While it has been shown that breeding of boreal birds of prey is first and foremost determined by prey abundance, little information exists...

In Finland, monitoring of ‘common’ birds of prey is based on two projects run by the Finnish Ringing Centre: the Raptor Grid (since 1982) and Raptor Questionnaire (since 1986). The Raptor Grid has produced sufficient data for analysing population trends in six of ten owl species. The overall trend during 1982–2007 was significantly negative in the...

Current climate change has been found to advance spring arrival and breeding dates of birds, but the effects on autumn migration and possible responses in the distribution of wintering individuals are poorly known. To thoroughly understand the consequences of climate change for animal life histories and populations, exploration of whole annual cycl...

We studied the concordance of population trends and indices between data from (1) the Finnish Constant Effort mist-netting Scheme (CES) and (2) line transect and point count based National Bird Monitoring Scheme (NMS). Population indices of nine common passerines between 1987-2006 were calculated with log-linear Poisson modelling (TRIM). The concor...

A changing climate induces shifts in the location of biomes. Tracing such a shift may pose problems for life history traits adapted to the prior conditions, so that, e.g. the timing of reproduction and the time with sufficient resources for rearing hatchlings do not match. We show that the timing of breeding of Finnish common buzzards Buteo buteo,...

In long-lived species, adult survival is the population parameter having the highest elasticity, and therefore, it can be expected to be least affected by climatic variations. We studied the dynamics and survival of breeding female common eiders Somateria mollissima mollissima in the Baltic Sea from 1960 to 2007. Using nest censuses and capture-rec...

Environmental quality has the potential to influence dispersal if cost of dispersing is outweighed by cost of staying. In that scenario, individuals experiencing different conditions in their natal area are expected to differ in their dispersal. Even if there is wide agreement that reasons behind the dispersal decision are multiple, it is often les...

We compared a method of moments approach using estimates from a maximum likelihood framework, ultrastructural models within a maximum likelihood framework, and hierarchical models estimated using Markov chain Monte Carlo within a Bayesian framework for estimating survival and recapture probabilities and their variance components for a large, comple...

In Finland, Comprehensive Surveys to monitor numbers and productivity of four endangered species of birds of prey were started in the early 1970s. In 1982, the Ringing Center launched the Raptor Grid, a nationwide monitoring program for all other bird-of-prey species based on 10 x 10 km study plots of the Finnish National Grid. The annual total of...

Vattulainen, A. 2008: Large-scale change in the sex ratio of a declining eider Somateria mollissima population. -Wildl. Biol. 14: 288-301. The breeding potential of a monogamous animal population should be maximal during equal operational sex ratio, and empirical evidence sug-gests that the population-wide sex ratio may be linked to population den-...

A method for comparing two migration routes is introduced. In the method are needed approximations of the average daily positions which are computed based on averages of dates and of positions in a window sliding through the encounters ordered in ascending order by date. The method contains two tests. The first, global, test statistic compares the...

Amateur bird ringers can collect data at a geographic and temporal scale that is rarely possible with professional field crews, thus allowing truly national analyses of population dynamics and dispersal. Since the early 1970s, bird ringers in Finland have been strongly encouraged to focus on birds of prey, especially cavity-nesting owls. In additio...

Survival rates of Tawny Owls (Strix aluco) were estimated using recapture and recovery data from approximately 20,000 nestling and adult owls ringed between 1980 and 1999 in southern Finland. Survival rates averaged 33% in the first year of life, 64% in the second, and 73% in subsequent years, but varied dramatically among years. Approximately 50%...

Voles in northern Europe have been shown to exhibit cyclic population dynamics, with a latitudinal gradient in cycle length, amplitude and interspecific synchrony. Previous studies have been based on a relatively sparse network of sampling sites. In the absence of spatially comprehensive long‐term records of vole dynamics, we analysed a proxy of vo...

Using nationwide long-term data on goshawk and grouse populations in Finland we study the spatial dynamics of the numbers of breeding northern goshawk (Accipiter gentilis) pairs, goshawk brood size and offspring sex ratio and their connection to the abundance of grouse. Our first large-scale data comprise of observations on goshawk nests during 198...

In many populations of size dimorphic birds, brood sex ratios change with advancing laying date. The slopes of these trends, however, vary in time and space, both between and within species. We studied brood sex ratios (proportion of males) of northern goshawks Accipiter gentilis in Finland in relation to laying date using ringing data from 1989 to...

Environmental quality has the potential to influence dispersal if cost of dispersing is outweighed by cost of staying. In that scenario, individuals experiencing different conditions in their natal area are expected to differ in their dispersal. Even if there is wide agreement that reasons behind the dispersal decision are multiple, it is often les...

Local population studies have shown that sex allocation among many birds and mammals seems to be partly non‐random and in connection to surrounding factors, such as environmental or parental quality. In this scenario, if environmental quality varies in space and time, it is feasible that environmental quality also comes to influence offspring sex r...

We compared estimates of annual survival rates of tawny owls ( Strix aluco ) ringed in southern Finland from several different sampling methods: recoveries of birds ringed as young; recaptures of birds ringed as young; recoveries of birds ringed as adults as well as young; combined recoveries and recaptures of birds ringed as young, and combined re...

Nearly all European Osprey (Pandion haliaetus) populations have had a similar fate during the 20th century. In the first two decades, if not earlier, dramatic decreases and even extirpations of many local populations occurred due to heavy persecution. There was then a recovery period until the second decrease from the 1950s to the mid-1970s, caused...

Saurola, P. 1994. African non-breeding areas of Fennoscandian Ospreys Pandion haliaetus: a ring recovery analysis. Ostrich 65:127-136.More than 36 000 Ospreys have been ringed in Fennoscandia up to 1992 and 638 of these have been reported from 30 different African countries. The recoveries suggest that adult and first-year Ospreys arrive in Norther...

The development of the Finnish Starling Sturnus vulgaris population was studied, us- ing data from 20 local populations and from the national ringing scheme extending from the beginning of the 1960s to the end of the 1980s (data for 7-26 years from each population) . According to local studies, the population size started to decrease in the late 19...

On the basis of Finnish ring recoveries, shows that natal dispersal was more extensive than breeding dispersal and more extensive among females than among males. The latter trend was found also in breeding dispersal: females, which are larger and adapted to preying on cyclically fluctuating voles, change their breeding areas more readily than males...

Reproduction of the Ural Owl was followed in a population of about 140 pairs on an area of $2200\ {\rm km}^{2}$ of south-boreal coniferous forests in Finland. All pairs bred in nest-boxes and almost every breeding female was ringed. We measured 331 clutches of 145 females in 1977-1984. The number of breeding pairs depended on the 3-4 year vole cycl...

Larus canus uses 2 distinct spatial units during the year, the Breeding Area and the Main Survival Area. The Survival Area is west of 14oE, from Denmark to Britain and France. Adults leave the Breeding Area as soon as breeding is over the 1st year birds following shortly after. Transitory areas are exploited briefly. The Main Survival Area appears...

Females did not start moulting their wing feathers until in the late nestling period or early fledgling period. No males were in active moult during the nestling period. The high number of moulted outer primaries in the first and subsequent moults may be adaptive because of the wear of the sound muffling combs on the leading edges of the outer prim...

Adults and first-year terns head south shortly after the young have fledged. The migration seems to occur in stages and the birds may exploit good feeding sites along the migration route for prolonged periods. The number of recoveries in Africa rises in November. The main area utilized by the terns from Finland, and probably the whole Baltic area,...

Analysed 1533 ring recoveries reported during the breeding season for individuals of different ages of great black-backed gull L. marinus, herring gull L. argentatus and lesser black-backed gull L. fuscus. Many adults of breeding age were recovered within 100 km of the natal site, 42.6% to 76.4% depending on the species and age-class (5 yr, 6-8 yr...

Biology and management of bald eagles and osprays: ed. by D. Bird, 325

Upon leaving the colonies, juvenile 1st-year birds disperse in various directions, but very few reach the main wintering area during early autumn. Recoveries centre around urban areas. Breeding adults participate in this dispersal to a lesser extent. The analysis of postnesting dispersal in adults is hampered by birds that have dispersed prior to t...

On the evidence of Finnish and Swedish ringing and recovery data the persecution of migrating raptors seems to have decreased dramatically in the second half of the 1960s in many European countries (i.e. in Central Europe, France and the USSR). In Italy adecline did not begin until ten years later. These data do not suggest any changes in persecuti...