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1.
Data Brief ; 31: 105724, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32478157

RESUMEN

We present the first dataset that can be used to associate peoples' opinions with comprehensive biodiversity and cultural heritage values. The socio-ecological dataset includes 1) place-based information on peoples' recreational activities, values expressed as pleasant and unpleasant sites, and negative preferences concerning land use in terms of tourism, nature protection and forestry, and 2) compiled information on scored biodiversity values and protection level of sites. The data are organized in 1ha grid cells. The data were compiled from a rural nature-based tourism area in two municipalities northern Finland. Peoples' opinions were assessed using a public participation geographic information system (PPGIS) and the data were merged with spatial biodiversity data from the same area. The data are directly related to the article Tolvanen et al. [1]. Biodiversity data, also utilized in Tolvanen et al. 2020, were compiled from various sources and scoring was done in Kangas et al. [2]. References to individual respondents and spatial locations of markings were removed. The data are useful in evaluating the relationship between people's values and biodiversity.

2.
Sci Rep ; 7(1): 1874, 2017 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-28500334

RESUMEN

The loss and subdivision of habitat into smaller and more spatially isolated units due to human actions has been shown to adversely affect species worldwide. We examined how changes in old forest cover during eight years were associated with the cumulative number of fledged offspring at the end of study period in Eurasian treecreepers (Certhia familiaris) in Central Finland. We were specifically interested in whether the initial level of old forest cover moderated this relation. We applied a flexible and powerful approach, latent growth curve modelling in a structural equation modeling (SEM) framework, to create trajectories describing changes in old forest cover through time, and studied how this change at both the territory core and landscape scales impacted fledging numbers. Our main finding was that at the territory core scale the negative impact of habitat loss on fledging numbers was lessened by the higher levels of initial forest cover, while no association was found at the landscape scale. Our study highlights a powerful, but currently under-utilised methodology among ecologists that can provide important information about biological responses to changes in the environment, providing a mechanistic way to study how land cover dynamics can affect species responses.


Asunto(s)
Biodiversidad , Aves , Ecosistema , Bosques , Árboles , Animales , Conservación de los Recursos Naturales , Finlandia , Humanos
3.
Environ Manage ; 53(5): 1005-14, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24556796

RESUMEN

Nature-based tourism and recreation within and close to protected areas may have negative environmental impacts on biodiversity due to urban development, landscape fragmentation, and increased disturbance. We conducted a 3-year study of disturbances of birds induced by nature-based tourism over a recreational gradient in the Pallas-Yllästunturi National Park and its surroundings in northern Finland. Bird assemblages were studied in highly disturbed areas close to the park (a ski resort, villages, and accommodation areas) and in campfire sites, along hiking routes (recreational areas) and in a forest (control area) within the park. Compared with the forest, the disturbed urbanized areas had higher abundances of human-associated species, corvid species, cavity and building nesters, and edge species. The abundances of managed forest species were higher in campfire sites than in the forest. Hiking trails and campfire sites did not have a negative impact on open-nesting bird species. The most likely reason for this outcome is that most campfire sites were situated at forest edges; this species group prefers managed forests and forest edge as a breeding habitat. The abundances of virgin forest species did not differ among the areas studied. The results of the study suggest that the current recreation pressure has not caused substantial changes in the forest bird communities within the National Park. We suggest that the abundances of urban exploiter species could be used as indicators to monitor the level and changes of urbanization and recreational pressure at tourist destinations.


Asunto(s)
Biodiversidad , Aves/fisiología , Conservación de los Recursos Naturales/estadística & datos numéricos , Ecosistema , Viaje/estadística & datos numéricos , Animales , Finlandia , Humanos , Modelos Lineales , Dinámica Poblacional , Recreación , Especificidad de la Especie , Árboles , Urbanización
4.
Insect Sci ; 21(4): 486-92, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23956057

RESUMEN

The fitness and survival of ant colonies depend on the resources near their nests. These resources may be limited due to poor habitat quality or by intra- and interspecific competitions, which in extreme cases may cause the ant colony to perish. We tested the effect of intraspecific competition and habitat degradation (forest clear-cutting) on colony survival by transplanting 26 nests of the red wood ant (Formica aquilonia Yarrow, 1955) in 26 different forest areas that contained 0-11 conspecific alien nests per hectare. F. aquilonia is highly dependent on canopy-dwelling aphids, thus the removal of trees should cause food limitation. During the course of the 4-year experiment, 9 of the forests were partially clear-cut. We found that while forest clear-cutting significantly decreased the colonies' survival, intraspecific competition did not. As a highly polygynous and polydomous species, F. aquilonia seems to tolerate the presence of alien conspecific colonies to a certain extent.


Asunto(s)
Hormigas/fisiología , Conducta Competitiva , Ecosistema , Agricultura Forestal/métodos , Bosques , Animales , Áfidos , Finlandia
5.
J Anim Ecol ; 82(5): 1087-97, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23550698

RESUMEN

1. There is great interest on the effects of habitat fragmentation, whereby habitat is lost and the spatial configuration of remaining habitat patches is altered, on individual breeding performance. However, we still lack consensus of how this important process affects reproductive success, and whether its effects are mainly due to reduced fecundity or nestling survival. 2. The main reason for this may be the way that habitat fragmentation has been previously modelled. Studies have treated habitat loss and altered spatial configuration as two independent processes instead of as one hierarchical and interdependent process, and therefore have not been able to consider the relative direct and indirect effects of habitat loss and altered spatial configuration. 3. We investigated how habitat (i.e. old forest) fragmentation, caused by intense forest harvesting at the territory and landscape scales, is associated with the number of fledged offspring of an area-sensitive passerine, the Eurasian treecreeper (Certhia familiaris). We used structural equation modelling (SEM) to examine the complex hierarchical associations between habitat loss and altered spatial configuration on the number of fledged offspring, by controlling for individual condition and weather conditions during incubation. 4. Against generally held expectations, treecreeper reproductive success did not show a significant association with habitat fragmentation measured at the territory scale. Instead, our analyses suggested that an increasing amount of habitat at the landscape scale caused a significant increase in nest predation rates, leading to reduced reproductive success. This effect operated directly on nest predation rates, instead of acting indirectly through altered spatial configuration. 5. Because habitat amount and configuration are inherently strongly collinear, particularly when multiple scales are considered, our study demonstrates the usefulness of a SEM approach for hierarchical partitioning of habitat amount vs. habitat configuration in landscape ecology that may have bearing on biological conclusions.


Asunto(s)
Fertilidad/fisiología , Modelos Teóricos , Passeriformes/crecimiento & desarrollo , Passeriformes/fisiología , Animales , Ecosistema , Finlandia , Comportamiento de Nidificación , Conducta Predatoria , Lluvia , Análisis Espacial , Temperatura , Árboles
6.
PLoS One ; 6(4): e19288, 2011 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-21559400

RESUMEN

BACKGROUND: Antagonistic species often interact via matching of phenotypes, and interactions between brood parasitic common cuckoos (Cuculus canorus) and their hosts constitute classic examples. The outcome of a parasitic event is often determined by the match between host and cuckoo eggs, giving rise to potentially strong associations between fitness and egg phenotype. Yet, empirical efforts aiming to document and understand the resulting evolutionary outcomes are in short supply. METHODS/PRINCIPAL FINDINGS: We used avian color space models to analyze patterns of egg color variation within and between the cuckoo and two closely related hosts, the nomadic brambling (Fringilla montifringilla) and the site fidelic chaffinch (F. coelebs). We found that there is pronounced opportunity for disruptive selection on brambling egg coloration. The corresponding cuckoo host race has evolved egg colors that maximize fitness in both sympatric and allopatric brambling populations. By contrast, the chaffinch has a more bimodal egg color distribution consistent with the evolutionary direction predicted for the brambling. Whereas the brambling and its cuckoo host race show little geographical variation in their egg color distributions, the chaffinch's distribution becomes increasingly dissimilar to the brambling's distribution towards the core area of the brambling cuckoo host race. CONCLUSION: High rates of brambling gene flow is likely to cool down coevolutionary hot spots by cancelling out the selection imposed by a patchily distributed cuckoo host race, thereby promoting a matching equilibrium. By contrast, the site fidelic chaffinch is more likely to respond to selection from adapting cuckoos, resulting in a markedly more bimodal egg color distribution. The geographic variation in the chaffinch's egg color distribution could reflect a historical gradient in parasitism pressure. Finally, marked cuckoo egg polymorphisms are unlikely to evolve in these systems unless the hosts evolve even more exquisite egg recognition capabilities than currently possessed.


Asunto(s)
Interacciones Huésped-Parásitos , Óvulo/fisiología , Passeriformes/genética , Animales , Color , Cáscara de Huevo , Evolución Molecular , Finlandia , Geografía , Modelos Lineales , Comportamiento de Nidificación , Noruega , Fenotipo , Probabilidad , Espectrofotometría/métodos , Suecia
7.
Biol Lett ; 6(4): 521-4, 2010 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-20129951

RESUMEN

Fluctuating asymmetry (FA) has been widely used as a stress-related phenotypic marker of developmental instability. However, previous studies relating FA to various stressful conditions have produced inconsistent results and we still lack quantitative individual-level evidence that high FA is related to stress in wild vertebrate species. We studied how baseline plasma levels of corticosterone predicted FA of wing and tail feathers in free-living Eurasian treecreeper (Certhia familiaris) nestlings. We found a sex-specific association between corticosterone levels and FA: high corticosterone levels were related to an increased FA in male but not in female nestlings. These results suggest that in treecreepers, FA may correlate with individual stress hormone levels, male developmental trajectory being potentially more sensitive to stress than that of the female.


Asunto(s)
Corticosterona/sangre , Plumas/anatomía & histología , Passeriformes/anatomía & histología , Estrés Fisiológico/fisiología , Animales , Teorema de Bayes , Plumas/fisiología , Femenino , Finlandia , Modelos Lineales , Masculino , Passeriformes/fisiología , Factores Sexuales
8.
BMC Evol Biol ; 8: 296, 2008 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-18954431

RESUMEN

BACKGROUND: Since Darwin's pioneering work, evolutionary changes in isolated island populations of vertebrates have continued to provide the strongest evidence for the theory of natural selection. Besides macro-evolutionary changes, micro-evolutionary changes and the relative importance of natural selection vs. genetic drift are under intense investigation. Our study focuses on the genetic differentiation in morphological and life-history traits in insular populations of a small mammal the bank vole Myodes glareolus. RESULTS: Our results do not support the earlier findings for larger adult size or lower reproductive effort in insular populations of small mammals. However, the individuals living on islands produced larger offspring than individuals living on the mainland. Genetic differentiation in offspring size was further confirmed by the analyses of quantitative genetics in lab. In insular populations, genetic differentiation in offspring size simultaneously decreases the additive genetic variation (VA) for that trait. Furthermore, our analyses of differentiation in neutral marker loci (Fst) indicate that VA is less than expected on the basis of genetic drift alone, and thus, a lower VA in insular populations could be caused by natural selection. CONCLUSION: We believe that different selection pressures (e.g. higher intraspecific competition) in an insular environment might favour larger offspring size in small mammals. Island selection for larger offspring could be the preliminary mechanism in a process which could eventually lead to a smaller litter size and lower reproductive effort frequently found in insular vertebrates.


Asunto(s)
Arvicolinae/fisiología , Tamaño Corporal/genética , Variación Genética , Geografía , Selección Genética , Animales , Peso al Nacer/genética , Peso Corporal , Femenino , Masculino , Reproducción/fisiología
9.
Proc Biol Sci ; 271(1537): 435-40, 2004 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-15101703

RESUMEN

We manipulated the primary brood size of Eurasian treecreepers (Certhia familiaris) breeding in different sized forest patches (0.5-12.8 ha) in moderately fragmented landscapes. We examined the effects of brood size manipulation (reduced, control, enlarged) and forest patch size on physiological stress (heterophil-lymphocyte ratios; H/L), body condition and cell-mediated immunocompetence (phytohaemagglutinin test). Nestlings' H/L ratios were negatively related to forest patch area in control and enlarged broods, whereas no effects were found in reduced broods. The effects of forest patch area were strongest in enlarged broods, which had, in general, twofold higher H/L ratios than control and reduced broods. The elevated H/L ratios were positively related to nestling mortality and negatively correlated with body-condition indices suggesting that the origin of stress in nestlings was mainly nutritional. Cell-mediated immunity of nestlings was not related to brood manipulation or to forest patch size. Also, the H/L ratios of adults were not related to brood manipulation or forest patch size. In addition, parental H/L ratios and body condition were not related to nestling H/L ratios. Our results suggest that during the breeding period the deleterious effects of habitat loss are seen explicitly in growing young.


Asunto(s)
Ambiente , Pájaros Cantores/inmunología , Pájaros Cantores/fisiología , Estrés Fisiológico/fisiopatología , Árboles , Animales , Finlandia , Leucocitos/inmunología , Modelos Lineales , Fitohemaglutininas/inmunología , Densidad de Población , Dinámica Poblacional
10.
Proc Biol Sci ; 270(1530): 2215-22, 2003 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-14613607

RESUMEN

We studied the primary brood sex ratio of an old-growth forest passerine, the Eurasian treecreeper (Certhia familiaris), along a gradient of forest fragmentation. We found evidence that male nestlings were more costly to produce, since they suffered twofold higher nestling mortality and were larger in body size than females. Furthermore, the proportion of males in the brood was positively associated with the provisioning rate and the amount of food delivered to the nestlings. During the first broods, a high edge density and a high proportion of pine forests around the nests were related to a decreased production of males. The densities of spiders, the main food of the treecreeper, were 38% higher on spruce trunks than on pine trunks. This suggests that pine-dominated territories with female-biased broods may have contained less food during the first broods. The observation was further supported by the fact that the feeding frequencies were lower in territories with high proportions of pines. In the second broods, territories with a high forest patch density produced female-biased broods, whereas high-quality territories with a large amount of deciduous trees and mixed forests produced male-biased broods. Our results suggest that habitat quality as measured by habitat characteristics is associated with sex allocation in free-living birds.


Asunto(s)
Ecología , Caracteres Sexuales , Razón de Masculinidad , Pájaros Cantores/fisiología , Árboles , Animales , Constitución Corporal/fisiología , Demografía , Dieta , Ambiente , Femenino , Masculino , Modelos Biológicos
11.
Proc Biol Sci ; 270(1518): 963-9, 2003 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-12803912

RESUMEN

We investigated how physiological stress in an area-sensitive old-growth forest passerine, the Eurasian treecreeper (Certhia familiaris), is associated with forest fragmentation and forest structure. We found evidence that the concentrations of plasma corticosterone in chicks were higher under poor food supply in dense, young forests than in sparse, old forests. In addition, nestlings in large forest patches had lower corticosterone levels and a better body condition than in small forest patches. In general, corticosterone levels were negatively related to body condition and survival. We also found a decrease in corticosterone levels within the breeding season, which may have been a result of an increase in food supply from the first to the second broods. Our results suggest that forest fragmentation may decrease the fitness of free-living individual treecreepers.


Asunto(s)
Enfermedades de las Aves/fisiopatología , Conservación de los Recursos Naturales , Agricultura Forestal , Pájaros Cantores/fisiología , Estrés Fisiológico/veterinaria , Animales , Animales Salvajes , Enfermedades de las Aves/sangre , Constitución Corporal , Corticosterona/sangre , Abastecimiento de Alimentos , Agricultura Forestal/métodos , Estrés Fisiológico/sangre , Estrés Fisiológico/fisiopatología
12.
Oecologia ; 117(1-2): 26-30, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28308496

RESUMEN

Several aspects of the life history of reindeer (Rangifer tarandus) are related to the nutritional condition of the animals. Moreover, compensatory growth and fattening in summer decreases with age. The interaction of tooth wear and the standing crop of lichens on age-related variation in body size and tissue reserves was examined to evaluate the proximate causes of density-dependent food limitation on life history parameters in female reindeer. Studies in nine semi-domesticated free-ranging reindeer herds showed that molar height depended on the mean standing crop of terrestrial lichens in winter habitats. The extent of tooth wear had the strongest effect on body reserves among the oldest females (11-14 years). This indicates that severe tooth wear limits the animals´ ability to process food efficiently and, hence, to maintain their body reserves. Both tooth wear and the biomass of lichens influenced body mass in old females, probably because on heavily exploited winter ranges reindeer had to use higher proportions of lower-ranking coarser foods, especially dwarf shrubs.

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