| 1. |
- Diaz, JA, et al.
(författare)
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Reproductive investment of a lacertid lizard in fragmented habitat
- 2005
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Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 19:5, s. 1578-1585
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Tidskriftsartikel (refereegranskat)abstract
- We studied the effect of habitat fragmentation on female reproductive investment in a widespread lacertid lizard (Psammodromus algirus) in a mixed-forest archipelago of deciduous and evergreen oak woods in northern Spain. We captured gravid females in fragments (<= 10 ha) and forests (>= 200 ha) and brought them to the laboratory, where they laid their eggs. We incubated the eggs and released the first cohort of juveniles into the wild to monitor their survival. Females from fragments produced a smaller clutch mass and laid fewer eggs (relative to mean egg mass) than females of similar body size from forests. Lizards did not trade larger clutches for larger offspring, however, because females from fragments did not lay larger eggs (relative to their number) than females from forests. Among the first cohort of juveniles, larger egg mass and body size increased the probability of recapture the next year Thus, fragmentation decreased the relative fecundity of lizards without increasing the quality of their offspring. Reduced energy availability, increased predation risk, and demographic stochasticity could decrease the fitness of lizards in fragmented habitats, which could contribute to the regional scarcity of this species in agricultural areas sprinkled with small patches of otherwise suitable forest. Our results show that predictable reduction of reproductive output with decreasing size of habitat patches can be added to the already known processes that cause inverse density dependence at low population numbers.
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| 2. |
- Larsson, Mattias, et al.
(författare)
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Pheromones for monitoring rare and threatened insects: exploiting a pheromone-kairomone system to estimate prey and predator abundance
- 2009
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 23:6, s. 1516-1525
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Tidskriftsartikel (refereegranskat)abstract
- Pheromone-based monitoring is a promising new method for assessing the conservation status of many threatened insect species. We examined the versatility and usefulness of pheromone-based monitoring by integrating a pheromone–kairomone trapping system and pitfall trapping system in the monitoring of two saproxylic beetles, the hermit beetle Osmoderma eremita (Coleoptera: Scarabaeidae) and its predator Elater ferrugineus (Coleoptera: Elateridae), which live inside hollow trees. We performed mark–recapture studies of both species with unbaited pitfall traps in oak hollows combined with pheromone-baited funnel traps suspended from oak branches to intercept dispersing individuals. For O. eremita, the integrated trapping system showed that the population in the study sites may be considerably higher than estimates based on extrapolation from pitfall trapping alone (approximately 3400 vs. 1100 or 1800 individuals, respectively). Recaptures between odor-baited funnel traps showed that males and females had similar dispersal rates, but estimating the number of dispersing individuals was problematic due to declining recapture probability between subsequent capture events. Our conservative estimate, assuming a linear decrease in capture probability, suggested that around 1900 individuals, or at least half of the O. eremita population, may perform flights from their natal host trees, representing higher dispersal rates than previous estimates. E. ferrugineus was rarely caught in pitfall traps. One hundred thirty-nine individuals, likely almost exclusively females, were caught in odor-baited funnel traps with approximately 4% recapture probability. If recapture probability over consecutive capture events follows that of O. eremita, this would correspond to a total population size of 2500–3000 individuals of the predator; similar to its supposed prey O. eremita. Our results demonstrate that pheromone-based monitoring is a valuable tool in the study of species or life-history stages that would otherwise be inaccessible.
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| 3. |
- Olsson, Ola
(författare)
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Genetic origin and success of reintroduced white storks
- 2007
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Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 21:5, s. 1196-1206
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Tidskriftsartikel (refereegranskat)abstract
- After their local extinction in 1954, White Storks (Ciconia ciconia) were reintroduced to Sweden in 1989. The founder Population for the reintroduced birds originated in North Africa, rather than from the closest breeding population in northeastern Europe (defined here as native). A number of wild storks have immigrated spontaneously, and a few others of native origin have been acquired for captive breeding. Over the 17 years, 103 of the 241 breeding events by free storks have been by pairs in which at least one parent had some native ancestry. The pedigree for all birds is known, and from this I calculated the proportion of native ancestry for each individual, the inbreeding coefficient, and the kinship between parents. I analyzed bow these genetic factors, together with rainfall during breeding, supplementary feeding, and management of the storks (whether parents were born or raised in captivity or free), affected brood size. I also analyzed whether storks with native ancestry had a higher likelihood of migrating. Together with weather and supplementary feeding during the breeding period, genetic origin strongly affected breeding performance. Pairs with entirely native ancestry had on average twice as many chicks as those of entirely Aftican ancestry. Inbreeding and kinship between parents, or management of the parents, did not influence breeding performance significantly. Reproductive success of the African storks in Sweden is so low that they cannot form a sustainable population. In addition, birds with some native ancestry were more likely to migrate from Sweden than those with entirely African ancestry. The difference in performance between native and African storks may be due either to local adaptations or to the bottleneck that the African founding population went through during captive breeding. Overall, my results imply that use of a correct source population for reintroduction programs may be of greater consequence for the program's success than other genetic considerations or management of individuals.
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| 4. |
- Pahkala, Maarit, et al.
(författare)
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Lethal and Sublethal Effects of UV-B/pH Synergism on Common Frog Embryos
- 2002
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Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 16:4, s. 1063-1073
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Tidskriftsartikel (refereegranskat)abstract
- Although the negative effects of ultraviolet-B ( UV-B) radiation on the development of many amphibian species have been demonstrated, some speciessuch as the common frog ( Rana temporaria)seem to be tolerant of UV-B radiation. The amount of UV-B radiation received is likely to vary among populations of the same species, but little is known about geographic variation in UV-B tolerance. Similarly, although UV-B radiation can have synergistic effects with other stressors, no studies have focused on geographic variation of these effects on amphibians. We investigated the synergistic effects of UV-B radiation and low pH on hatchability and early development of R. temporaria embryos in a factorial laboratory experiment with animals originating from southern and northern Sweden. Newly fertilized eggs were exposed to three different UV-B treatments (no UV-B [control, 1.254 k/J/m 2[normal and 1.584 k/J/m 2[26 enhanced) and two pH treatments (4.5 [low and 7.6 [neutral). Ultraviolet-B radiation in combination with low pH lead to markedly (approximately 50) reduced survival rates and increased (approximately 30) frequency of developmental anomalies in the northern but not in the southern population. The UV-B- exposed embryos hatched at smaller size in the southern population, whereas low pH reduced hatchling size in both populations. In both populations and pH treatments, embryos in the normal UV-B treatment developed significantly faster than embryos in the enhanced or control UV-B treatments. No interaction between pH and UV-B on developmental rates or hatchling size was detected. The results demonstratecontrary to earlier beliefthat R. temporaria embryos are not insensitive to increased levels of UV-B radiation. The lethal effects of UV-B radiation may, however, become manifested only in combination with other stressors, such as low pH, and the effects of this synergism may differ among different populations of the same species.
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| 5. |
- Peterson, Garry, 1969-
(författare)
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A Cross-National Analysis of How Economic Inequality Predicts Biodiversity Loss
- 2009
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Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 23:5, s. 1304-1313
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Tidskriftsartikel (refereegranskat)abstract
- We used socioeconomic models that included economic inequality to predict biodiversity loss, measured as the proportion of threatened plant and vertebrate species, across 50 countries. Our main goal was to evaluate whether economic inequality, measured as the Gini index of income distribution, improved the explanatory power of our statistical models. We compared four models that included the following: only population density, economic footprint (i.e., the size of the economy relative to the country area), economic footprint and income inequality (Gini index), and an index of environmental governance. We also tested the environmental Kuznets curve hypothesis, but it was not supported by the data. Statistical comparisons of the models revealed that the model including both economic footprint and inequality was the best predictor of threatened species. It significantly outperformed population density alone and the environmental governance model according to the Akaike information criterion. Inequality was a significant predictor of biodiversity loss and significantly improved the fit of our models. These results confirm that socioeconomic inequality is an important factor to consider when predicting rates of anthropogenic biodiversity loss.
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| 6. |
- Berglund, Håkan, et al.
(författare)
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Quantifying habitat requirements of tree-living species in fragmented boreal forests with Bayesian methods
- 2009
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 23:5, s. 1127-1137
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Tidskriftsartikel (refereegranskat)abstract
- Quantitative conservation objectives require detailed consideration of the habitat requirements of target species. Tree-living bryophytes, lichens, and fungi are a critical and declining biodiversity component of boreal forests. To understand their requirements, Bayesian methods were used to analyze the relationships between the occurrence of individual species and habitat factors at the tree and the stand scale in a naturally fragmented boreal forest landscape. The importance of unexplained between-stand variation in occurrence of species was estimated, and the ability of derived models to predict species' occurrence was tested. The occurrence of species was affected by quality of individual trees. Furthermore, the relationships between occurrence of species at the tree level and size and shape of stands indicated edge effects, implying that some species were restricted to interior habitats of large, regular stands. Yet for the habitat factors studied, requirements of many species appeared similar. Species occurrence also varied between stands; most of the seemingly suitable trees in some stands were unoccupied. The models captured most variation in species occurrence at tree level. They also successfully accounted for between-stand variation in species occurrence, thus providing realistic simulations of stand-level occupancy of species. Important unexplained between-stand variation in species occurrence warns against a simplified view that only local habitat factors influence species' occurrence. Apparently, similar stands will host populations of different sizes due to historical, spatial, and stochastic factors. Thus, habitat suitability cannot be assessed simply by population sizes, and stands lacking a species may still provide suitable habitat and merit protection.
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| 7. |
- Berglund, H., et al.
(författare)
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Verifying an Extinction Debt among Lichens and Fungi in Northern Swedish Boreal Forests
- 2005
-
Ingår i: Conservation Biology. - : John Wiley & Sons. - 0888-8892 .- 1523-1739. ; 19:2, s. 338-348
-
Tidskriftsartikel (refereegranskat)abstract
- Destruction and fragmentation of natural habitats results in small species populations that face increased risk of extinction. A time delay may be involved in the regional extinction of species, and the number of species that eventually may go extinct in the future is called the “extinction debt.” In boreal Sweden, we examined whether the number of epiphytic crustose lichens and wood-inhabiting fungi in old-growth forest remnants diverges from species richness levels in forest patches that have been naturally isolated for millennia. An excess of species in forest remnants could indicate the presence of an extinction debt. Observed species richness in 32 old-growth forest remnants (also called woodland key habitats [WKHs]) was compared with predicted species richness. To predict species richness we used regression models based on data from 46 isolated old-growth forest patches in a forest-wetland matrix. The reference landscape is ancient and assumed to reflect the conditions of insular floras in dynamic equilibrium. Stand factors constituted predictive variables in the models. The observed number of lichen species was higher than expected (i.e., an extinction debt among lichens may exist). By contrast, there was no significant difference between observed and expected species richness among wood-inhabiting fungi. The species richness of wood-inhabiting fungi has adjusted to the changes in forest and landscape structure more rapidly than the species richness of lichens. Differences in substrate dynamics between epiphytes on living trees and species growing on decaying logs might explain the difference between species groups. The results also indicate that population densities of red-listed species were low, which may result in continuing extinctions of red-listed species. The importance of WKHs might be overvalued because species may be lost if conservation efforts consider only protection and preservation of WKHs.
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| 8. |
- Berglund, Håkan, et al.
(författare)
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Verifying an extinction debt in north Swedish boreal forests
- 2005
-
Ingår i: Conservation biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 19:2, s. 338-348
-
Tidskriftsartikel (refereegranskat)abstract
- Destruction and fragmentation of natural habitats results in small species populations that face increased risk of extinction. A time delay may be involved in the regional extinction of species, and the number of species that eventually may go extinct in the future is called the "extinction debt." In boreal Sweden, we examined whether the number of epiphytic crustose lichens and wood-inhabiting fungi in old-growth forest remnants diverges from species richness levels in forest patches that have been naturally isolated for millennia. An excess of species in forest remnants could indicate the presence of an extinction debt. Observed species richness in 32 old-growth forest remnants (also called woodland key habitats [WKHs]) was compared with predicted species richness. To predict species richness we used regression models based on data from 46 isolated old-growth forest patches in a forest-wetland matrix. The reference landscape is ancient and assumed to reflect the conditions of insular floras in dynamic equilibrium. Stand factors constituted predictive variables in the models. The observed number of lichen species was higher than expected (i.e., an extinction debt among lichens may exist). By contrast, there was no significant difference between observed and expected species richness among wood-inhabiting fungi. The species richness of wood-inhabiting fungi has adjusted to the changes in forest and landscape structure more rapidly than the species richness of lichens. Differences in substrate dynamics between epiphytes on living trees and species growing on decaying logs might explain the difference between species groups. The results also indicate that population densities of red-listed species were low, which may result in continuing extinctions of red-listed species. The importance of WKHs might be overvalued because species may be lost if conservation efforts consider only protection and preservation of WKHs.
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| 9. |
- Cassel, Anna, et al.
(författare)
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Effects of population size and food stress on fitness-related characters in the scarce heath, a rare butterfly in Western Europe
- 2001
-
Ingår i: Conservation Biology. - : Blackwell Science Publishing. - 0888-8892 .- 1523-1739. ; 15:6, s. 1667-1673
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Tidskriftsartikel (refereegranskat)abstract
- Abstract: Knowledge about the effects of inbreeding in natural populations is scarce, especially in invertebrates. We analyzed to what extent fitness-related traits in the scarce heath ( Coenonympha hero), a butterfly, are affected by population size and isolation and whether differences in food quality influence these effects. We categorized nine populations as either large or small and isolated. Full-sib groups of offspring from 27 females were followed under seminatural conditions. Because of increased zygote mortality, egg hatchability was significantly lower in the small and isolated populations than in the large ones. Population category had no effect on larval weight under optimal conditions, but weight was significantly lower in the small-isolated category with low food quality. The effects of inbreeding can thus be hidden when conditions are benign but can appear under stress. Survival also differed significantly between population categories, and larval developmental time tended to be longer in the small-isolated category, irrespective of food conditions. We suggest that the differences in fitness between offspring from large and small isolated populations are at least partly due to inbreeding. This adds a further threat to a species that is already suffering from decreasing population sizes and increasing isolation among populations.
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| 10. |
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| 11. |
- Evans, Simon, 1984-, et al.
(författare)
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Interspecific patterns of genetic diversity in birds : correlations with extinction risk
- 2008
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 22:4, s. 1016-1025
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Tidskriftsartikel (refereegranskat)abstract
- Birds are frequently used as indicators of ecosystem health and are the most comprehensively studied class in the animal kingdom. Nevertheless, a comprehensive, interspecific assessment of the correlates of avian genetic diversity is lacking, even though indices of genetic diversity are of considerable interest in the conservation of threatened species. We used published data on variation at microsatellite loci from194 bird species to examine correlates of diversity, particularly with respect to conservation status and population size. We found a significant decline in mean heterozygosity with increasing extinction risk, and showed, by excluding species whose heterozygosity values were calculated with heterospecific primers, that this relationship was not dependent on ascertainment bias. Results of subsequent regression analyses suggested that smaller population sizes of threatened species were largely responsible for this relationship. Thus, bird species at risk of extinction are relatively depauperate in terms of neutral genetic diversity, which is expected to make population recovery more difficult if it reflects adaptive genetic variation. Conservation policy will need to minimize further loss of diversity if the chances of saving threatened species are to be maximized.
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| 12. |
- Forsman, Anders, et al.
(författare)
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Association of coloration mode with population declines and endangerment in Australian frogs
- 2009
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 23:6, s. 1535-1543
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Tidskriftsartikel (refereegranskat)abstract
- Successful protection of biodiversity requires increased understanding of the ecological characteristics that predispose some species to endangerment. Theory posits that species with polymorphic or variable coloration should have larger distributions, use more diverse resources, and be less vulnerable to population declines and extinctions, compared with taxa that do not vary in color. We used information from literature on 194 species of Australian frogs to search for associations of coloration mode with ecological variables. In general, species with variable or polymorphic color patterns had larger ranges, used more habitats, were less prone to have a negative population trend, and were estimated as less vulnerable to extinction compared with nonvariable species. An association of variable coloration with lower endangerment was also evident when we controlled statistically for the effects of range size. Nonvariable coloration was not a strong predictor of endangerment, and information on several characteristics is needed to reliably identify and protect species that are prone to decline and may become threatened by extinction in the near future. Analyses based on phylogenetic-independent contrasts did not support the hypothesis that evolutionary transitions between nonvariable and variable or polymorphic coloration have been accompanied by changes in the ecological variables we examined. Irrefutable demonstration of a role of color pattern variation in amphibian decline and in the dynamics and persistence of populations in general will require a manipulative experimental approach.
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| 13. |
- Fries, Ingemar
(författare)
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Estimating the Density of Honeybee Colonies across Their Natural Range to Fill the Gap in Pollinator Decline Censuses
- 2010
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Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 24, s. 583-593
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Tidskriftsartikel (refereegranskat)abstract
- Although pollinator declines are a global biodiversity threat, the demography of the western honeybee (Apis mellifera) has not been considered by conservationists because it is biased by the activity of beekeepers. To fill this gap in pollinator decline censuses and to provide a broad picture of the current status of honeybees across their natural range, we used microsatellite genetic markers to estimate colony densities and genetic diversity at different locations in Europe, Africa, and central Asia that had different patterns of land use. Genetic diversity and colony densities were highest in South Africa and lowest in Northern Europe and were correlated with mean annual temperature. Confounding factors not related to climate, however, are also likely to influence genetic diversity and colony densities in honeybee populations. Land use showed a significantly negative influence over genetic diversity and the density of honeybee colonies over all sampling locations. In Europe honeybees sampled in nature reserves had genetic diversity and colony densities similar to those sampled in agricultural landscapes, which suggests that the former are not wild but may have come from managed hives. Other results also support this idea: putative wild bees were rare in our European samples, and the mean estimated density of honeybee colonies on the continent closely resembled the reported mean number of managed hives. Current densities of European honeybee populations are in the same range as those found in the adverse climatic conditions of the Kalahari and Saharan deserts, which suggests that beekeeping activities do not compensate for the loss of wild colonies. Our findings highlight the importance of reconsidering the conservation status of honeybees in Europe and of regarding beekeeping not only as a profitable business for producing honey, but also as an essential component of biodiversity conservation.
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| 14. |
- Gray, Michael A., et al.
(författare)
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The response of avian feeding guilds to tropical forest disturbance.
- 2007
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Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 21:1, s. 133-141
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Tidskriftsartikel (refereegranskat)abstract
- Anthropogenic habitat disturbance is a major threat to tropical forests and understanding the ecological consequences of this disturbance is crucial for the conservation of biodiversity. There have been many attempts to determine the ecological traits associated with bird species' vulnerability to disturbance, but no attempt has been made to synthesize these studies to show consensus. We analyzed data from 57 published studies (covering 1214 bird species) that investigated the response of tropical bird assemblages to moderate forest disturbance (e.g., selective logging). Our results show that the mean abundance of species from six commonly reported feeding guilds responded differently to disturbance and that species' ecological traits (body size, local population size, and geographic range size) and evolutionary relationships may influence responses in some guilds. Granivore abundance increased significantly and insectivore and frugivore abundance decreased significantly following disturbance. These general conclusions were robust to the effects of ecological traits and phylogeny. Responses of carnivores, nectarivores, and omnivores were less clear, but analyses that accounted for phylogeny indicated that these guilds declined following disturbance. In contrast to the other guilds, the reported responses of carnivores and nectarivores differed among regions (Asia vs. Neotropics) and were influenced by the sampling protocols used in different studies (e.g., time since disturbance), which may explain the difficulty in detecting general responses to disturbance in these guilds. Overall, general patterns governed the responses of species to habitat disturbance, and the differential responses of guilds suggested that disturbance affects trophic organization and thus ecosystem functioning.
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| 15. |
- Griesser, Michael, et al.
(författare)
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Impact of forestry practices on fitness correlates and population productivity in an open-nesting bird species
- 2007
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 21:3, s. 767-774
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Tidskriftsartikel (refereegranskat)abstract
- In the boreal forests of Fennoscandia, over 99% of forest area has been altered by forestry practices, which has created forest with age structures and stand characteristics that differ from primary forest stands. Although many researchers have investigated how forestry affects species abundance, few have assessed how forestry practices affect fitness correlates of species living in altered habitats, and this has negatively affected management efforts. We experimentally addressed the effect of standard forestry practices on fitness correlates of an open-nesting, long-lived bird species typical to boreal forests of Eurasia, the Siberian Jay (Perisoreus infaustus). We used a before-after comparison of reproductive data on the level of territories and found that standard forestry practices had a strong negative effect on the breeding success of jays. Both partial thinning of territories and partial clearcutting of territories reduced future breeding success by a factor of 0.35. Forestry practices reduced territory occupancy. Thus, over the 15 years of the study, productivity of the affected population declined over 50% as a result of territory abandonment and reduced breeding success. Results of previous studies on Siberian Jays suggest that the strong effect of forest thinning on fitness is explained by the fact that most common predators of nests and adults are visually oriented and thus thinning makes prey and nests more visible to predators. The consequences of thinning we observed are likely to apply to a wide range of species that rely on understory to provide visual protection from predators. Thus, our results are important for the development of effective conservation management protocols and for the refinement of thinning practices.
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| 16. |
- Heberlein, Thomas
(författare)
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Navigating Environmental Attitudes
- 2012
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Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 26, s. 583-585
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Annan publikation (refereegranskat)
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| 17. |
- Hjältén, Joakim, et al.
(författare)
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Biodiversity Differences between Managed and Unmanaged Forests: Meta-Analysis of Species Richness in Europe
- 2010
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 24, s. 101-112
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Tidskriftsartikel (refereegranskat)abstract
- Past and present pressures on forest resources have led to a drastic decrease in the surface area of unmanaged forests in Europe. Changes in forest structure, composition, and dynamics inevitably lead to changes in the biodiversity of forest-dwelling species. The possible biodiversity gains and losses due to forest management (i.e., anthropogenic pressures related to direct forest resource use), however, have never been assessed at a pan-European scale. We used meta-analysis to review 49 published papers containing 120 individual comparisons of species richness between unmanaged and managed forests throughout Europe. We explored the response of different taxonomic groups and the variability of their response with respect to time since abandonment and intensity of forest management. Species richness was slightly higher in unmanaged than in managed forests. Species dependent on forest cover continuity, deadwood, and large trees (bryophytes, lichens, fungi, saproxylic beetles) and carabids were negatively affected by forest management. In contrast, vascular plant species were favored. The response for birds was heterogeneous and probably depended more on factors such as landscape patterns. The global difference in species richness between unmanaged and managed forests increased with time since abandonment and indicated a gradual recovery of biodiversity. Clearcut forests in which the composition of tree species changed had the strongest effect on species richness, but the effects of different types of management on taxa could not be assessed in a robust way because of low numbers of replications in the management-intensity classes. Our results show that some taxa are more affected by forestry than others, but there is a need for research into poorly studied species groups in Europe and in particular locations. Our meta-analysis supports the need for a coordinated European research network to study and monitor the biodiversity of different taxa in managed and unmanaged forests.
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| 18. |
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| 19. |
- Hylander, K, et al.
(författare)
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Effects of buffer-strip retention and clearcutting on land snails in boreal riparian forests
- 2004
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Ingår i: Conservation Biology. - Boston : Wiley. - 0888-8892 .- 1523-1739. ; 18:4, s. 1052-1062
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Tidskriftsartikel (refereegranskat)abstract
- We investigated the short-term effects of forest clearcutting on land snails (terrestrial gastropods) in 15 forest stands along small streams in Sweden. Two different silvicultural treatments were applied at each site: clearcutting across the stream channel and buffer strips 10 m wide on each side of the stream. Additionally, we studied 10 reference sites in unlogged riparian forests along similar-sized streams. All sites were studied before logging and then 2.5 years after logging. After clearcutting the number of individuals in a 0.5-m(2) sample from each site decreased on average from 107 to 87, and the mean number of species per sample decreased from 9.9 to 7.7. Most species were negatively affected, but there were also clear differences in sensitivity. There were correlations between species survival and ground moisture. At the wettest clearcut sites with an almost intact bryophyte cover, the land snails were unaffected by clearcutting. This result suggests that wet or moist forest floors can serve as refugia even at very small spatial scales (e.g., shallow hollows, crevices). If this is an important mechanism, the spatial distribution of small habitats could be important for the long-term survival of the snail fauna or other small, dispersal-limited organisms at clearcut sites. In the buffer strips, the number of individuals decreased but not the number of species, indicating that buffer-strip retention is a good practice for protecting land snails in riparian forests. The varying effectiveness of the buffer strip could partly be explained by the proportion of the remaining basal area, emphasizing that buffer strips could be even more effective if efforts are made to avoid heavy damage by windthrows.
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| 20. |
- Kolm, Niclas, et al.
(författare)
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Wild Populations of a Reef Fish Suffer from the “Nondestructive” Aquarium Trade Fishery
- 2003
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Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 17:3, s. 910-914
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Tidskriftsartikel (refereegranskat)abstract
- The commercial fishery for coral reef fish for the aquarium trade has begun to change, at least in some parts of the world, from destructive methods such as cyanide and dynamite fishing to less-destructive methods such as hand-net fishing. However, data on the effects on wild populations of such relatively nondestructive methods is nonexistent. The Banggai cardinalfish ( Pterapogon kauderni ) is a paternal mouthbrooder living in groups of 2–200 individuals in the proximity of sea urchins ( Diadema setosum ). This fish has limited dispersal abilities because it lacks a pelagic larval phase, and it is believed to be endemic to the Banggai archipelago off the east coast of Sulawesi, Indonesia. Since its rediscovery in 1995, the Banggai cardinalfish has become a popular aquarium fish, and thousands have been exported—mainly to North America, Japan, and Europe. To study the effects of the aquarium trade fishery on wild populations of the Banggai cardinalfish, we performed a field study in which we quantified density, age distribution ( quantified as the ratio of numbers of juveniles to adults ) and habitat quality ( i.e., sea urchin density ) at eight sites in the Banggai archipelago. Through interviews with local fishers, we estimated the fishing pressure at each site and related this to data on fish density. We found a marginally significant negative effect of fishing pressure on density of fish and significant negative effects on group size in both sea urchins and fish. We did not find any effect of fishing on fish size structure. To our knowledge this is the first study to compare sites under different amounts of fishing pressure that has demonstrated the negative effects of the aquarium trade on wild populations of reef fish, despite the widespread use of relatively nondestructive fishing methods.
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| 21. |
- Laikre, Linda, et al.
(författare)
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Hunting Effects on Favourable Conservation Status of Highly Inbred Swedish Wolves
- 2013
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 27:2, s. 248-253
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Tidskriftsartikel (refereegranskat)abstract
- The wolf (Canis lupus) is classified as endangered in Sweden by the Swedish Species Information Centre, which is the official authority for threat classification. The present population, which was founded in the early 1980s, descends from 5 individuals. It is isolated and highly inbred, and on average individuals are more related than siblings. Hunts have been used by Swedish authorities during 2010 and 2011 to reduce the population size to its upper tolerable level of 210 wolves. European Union (EU) biodiversity legislation requires all member states to promote a concept called “favourable conservation status” (FCS) for a series of species including the wolf. Swedish national policy stipulates maintenance of viable populations with sufficient levels of genetic variation of all naturally occurring species. Hunting to reduce wolf numbers in Sweden is currently not in line with national and EU policy agreements and will make genetically based FCS criteria less achievable for this species. We suggest that to reach FCS for the wolf in Sweden the following criteria need to be met: (1) a well-connected, large, subdivided wolf population over Scandinavia, Finland, and the Russian Karelia-Kola region should be reestablished, (2) genetically effective size (Ne) of this population is in the minimum range of Ne = 500–1000, (3) Sweden harbors a part of this total population that substantially contributes to the total Ne and that is large enough to not be classified as threatened genetically or according to IUCN criteria, and (4) average inbreeding levels in the Swedish population are <0.1.
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| 22. |
- Laikre, Linda, et al.
(författare)
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Importance of Genetics in the Interpretation of Favourable Conservation Status
- 2009
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 23, s. 1378-1381
-
Tidskriftsartikel (refereegranskat)abstract
- “Favourable Conservation Status” (FCS) is a central concept in the biodiversity conservation legislation of the European Union (EU). Here, we highlight the importance of incorporating aspects of conservation genetics in interpretation of this concept. Recent documents from the EU Commission indicate that knowledge of conservation genetics has so far been lacking among those who have tried to employ the concept. We think it is crucial that aspects of conservation genetics be incorporated in discussion of this concept and that this be done before the EU Court of Justice takes a position on the legal interpretation of FCS.
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| 23. |
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| 24. |
- Laikre, Linda, et al.
(författare)
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Wanted : Scientists in the CBD process
- 2008
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 22:4, s. 814-815
-
Tidskriftsartikel (refereegranskat)
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| 25. |
- Lehtilä, Kari, et al.
(författare)
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Habitat change and demography of Primula veris : Identification of management targets
- 2006
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Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 20:3, s. 833-843
-
Tidskriftsartikel (refereegranskat)abstract
- Although the effects of deterministic factors on population viability often are more important than stochasticity, few researchers have dealt with the effect of deterministic habitat changes on plant population demography We assessed population viability for the perennial herb Primula veris L. and identified targets for management based on demographic data from five different habitat types representing different degrees of canopy closure. We conducted replicate studies at the border of the distribution area and in more central parts. Demographic patterns were similar between the two regions. Most study populations had a positive population growth, and only populations in late phases of forest succession showed consistently negative trends. The populations of open habitats had high seedling recruitment, and the populations of early and middle forest succession had high seed production. The importance of survival for population growth rate increased with increasing habitat closure, whereas the importance of growth and reproduction decreased. Results of the elasticity analysis suggested that the best method to manage decreasing late-successional populations is to increase survival of the largest individuals. The life-table response experiment (LTRE) analysis, however, showed that survival of the largest individuals contributed little to differences in population growth rates of different habitats, whereas seed production and growth of small individuals were more important. Moreover, direct perturbation of the performance of the largest stages showed that late-successional populations would not attain positive population growth even if the largest stages had no mortality at all. We conclude that restoration of recruitment is the only possibility for positive population growth in late-successional populations of P. veris, although the elasticities of recruitment transitions are low. Our results also suggest that retrospective demographic methods such as LIRE constitute an important and necessary complement to prospective methods such as elasticities in identifying management targets.
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| 26. |
- Lindborg, Regina, et al.
(författare)
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Evaluating the extinction risk of a perennial herb : demographic data versus historical records
- 2002
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Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 16:3, s. 683-690
-
Tidskriftsartikel (refereegranskat)abstract
- Demographic information is frequently used to project the long-term extinction risk of endangered species, but the limitations of this approach have not been extensively discussed. We examined demographic data for the endangered perennial herb Primula farinosa with matrix models to assess population growth rates and extinction risks. The data came from six populations in contrasting habitats followed over a 4-year period. The results of these demographic models were compared to the results of experimental manipulations and to the actual change in occurrence of P. farinosa over a 70-year period in different habitat types. According to demographic models, all managed populations had a projected negative population growth rate and experienced a high extinction risk in 100 years, whereas unmanaged populations had increasing population sizes. In contrast, experiments and historical records suggested that continuous grazing is positively correlated with population persistence. Our results thus show that demographic studies done during a transient phase of population growth after management cessation may not capture the long-term changes. In such cases, projections of population growth rates may give misleading guidance for conservation. Short-term demographic studies are in many cases unlikely to correctly assess the survival probability of a species. We therefore argue that complementary information, such as long-term historical data or experimental manipulations of the environment, should be used whenever possible.
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| 27. |
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| 28. |
- Milbau, Ann, et al.
(författare)
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Factors associated with alien plants transitioning from casual, to naturalized, to invasive.
- 2008
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 22:2, s. 308-17
-
Tidskriftsartikel (refereegranskat)abstract
- To explain current plant invasions, or predict future ones, more knowledge on which factors increase the probability of alien species becoming naturalized and subsequently invasive is needed. We created a database of the alien plants in seminatural habitats in Ireland that included data on taxonomy, invasive status, invasion history, distribution, and biological and ecological plant characteristics. We used information from this database to determine the importance of these factors in increasing the ability of species to become naturalized and invasive. More specifically, we used two multiple logistic regressions to identify factors that distinguish naturalized from casual alien plant species and invasive from noninvasive, naturalized alien species. Clonal growth, moisture-indicator value, nitrogen-indicator value, native range, and date of first record affected (in order of decreasing importance) the probability of naturalization. Factors that distinguished invasive from noninvasive species were ornamental introduction, hermaphrodite flowers, pollination mode, being invasive elsewhere, onset of flowering season, moisture-indicator value, native range, and date of first record. Incorporation of phylogenetic information had little influence on the results, suggesting that the capacity of alien species to naturalize and become invasive evolved largely independently in several phylogenetic lineages. Whereas some of the variables were important for both transitions, others were only important for naturalization or for invasion. This emphasizes the importance of studying different stages of the invasion process when looking for mechanisms of becoming a successful invasive plant, instead of simply comparing invasive with noninvasive alien species. Our results also suggest that a combination of species traits and other variables is likely to produce the most accurate prediction of invasions.
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| 29. |
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| 30. |
- Paltto, Heidi, et al.
(författare)
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Multispecies and Multiscale Conservation Planning : Setting Quantitative Targets for Red-Listed Lichens on Ancient Oaks
- 2010
-
Ingår i: Conservation Biology. - : Society for Conservation Biology. - 0888-8892 .- 1523-1739. ; 24:3, s. 758-768
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Tidskriftsartikel (refereegranskat)abstract
- Species occurrence in a habitat patch depends on local habitat and the amount of that habitat in the wider landscape. We used predictions from empirical landscape studies to set quantitative conservation criteria and targets in a multispecies and multiscale conservation planning effort. We used regression analyses to compare species richness and occurrence of five red-listed lichens on 50 ancient oaks (Quercus robur; 120–140 cm in diameter) with the density of ancient oaks in circles of varying radius from each individual oak. Species richness and the occurrence of three of the five species were best explained by increasing density of oaks within 0.5 km; one species was best explained by the density of oaks within 2 km, and another was best predicted by the density of oaks within 5 km. The minimum numbers of ancient oaks required for “successful conservation” was defined as the number of oaks required to obtain a predicted local occurrence of 50% for all species included or a predicted local occurrence of 80% for all species included. These numbers of oaks were calculated for two relevant landscape scales (1 km2 and 13 km2) that corresponded to various species responses, in such a way that calculations also accounted for local number of oaks. Ten and seven of the 50 ancient oaks surveyed were situated in landscapes that already fulfilled criteria for successful conservation when the 50% and 80% criteria, respectively, were used to define the level of successful conservation. For cost-efficient conservation, oak stands in the landscapes most suitable for successful conservation should be prioritized for conservation and management (e.g., grazing and planting of new oaks) at the expense of oak stands situated elsewhere.
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| 31. |
- Peterson, Tarla
(författare)
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Obscuring Ecosystem Function with Application of the Ecosystem Services Concept
- 2010
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 24, s. 113-119
-
Tidskriftsartikel (refereegranskat)abstract
- Conservationists commonly have framed ecological concerns in economic terms to garner political support for conservation and to increase public interest in preserving global biodiversity. Beginning in the early 1980s, conservation biologists adapted neoliberal economics to reframe ecosystem functions and related biodiversity as ecosystem services to humanity. Despite the economic success of programs such as the Catskill/Delaware watershed management plan in the United States and the creation of global carbon exchanges, today's marketplace often fails to adequately protect biodiversity. We used a Marxist critique to explain one reason for this failure and to suggest a possible, if partial, response. Reframing ecosystem functions as economic services does not address the political problem of commodification. Just as it obscures the labor of human workers, commodification obscures the importance of the biota ( ecosystem workers) and related abiotic factors that contribute to ecosystem functions. This erasure of work done by ecosystems impedes public understanding of biodiversity. Odum and Odum's radical suggestion to use the language of ecosystems (i.e., emergy or energy memory) to describe economies, rather than using the language of economics (i.e., services) to describe ecosystems, reverses this erasure of the ecosystem worker. Considering the current dominance of economic forces, however, implementing such solutions would require social changes similar in magnitude to those that occurred during the 1960s. Niklas Luhmann argues that such substantive, yet rapid, social change requires synergy among multiple societal function systems (i.e., economy, education, law, politics, religion, science), rather than reliance on a single social sphere, such as the economy. Explicitly presenting ecosystem services as discreet and incomplete aspects of ecosystem functions not only allows potential economic and environmental benefits associated with ecosystem services, but also enables the social and political changes required to ensure valuation of ecosystem functions and related biodiversity in ways beyond their measurement on an economic scale.
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| 32. |
- Rydin, Håkan, et al.
(författare)
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Biological characteristics, habitat associations, and distribution of macrofungi in Sweden
- 1997
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Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 11:3, s. 628-640
-
Tidskriftsartikel (refereegranskat)abstract
- We conducted a statistical analysis of taxonomic and functional groups, of some ecological characteristics (edaphic factors, macro- and micro-habitats) and of the distribution of macrofungi in Sweden, based on an ecological data catalog of 3196 species. We placed particular emphasis on a comparison of threatened and non-threatened taxa. Differences in the proportions of threatened macrofungi were found among both taxonomic and functional groups, partly explained by a lack of information on some of the groups. A comparatively high proportion of threatened macrofungi is found on dry and base-rich soils. High relative numbers of threatened taxa occur in semi-natural open habitats such as calcareous grasslands and in southern deciduous hardwood forests on high-pH soils. Another habitat type of major importance for red-listed species is the boreal spruce forest. A high proportion of the wood-inhabiting species are red-listed; this is probably a result of the dramatic decrease in decaying wood in Swedish forests during this century. Both the absolute number of species and the absolute and relative numbers of threatened species decrease from south to north. Many functional and habitat characteristics differed between regions. Our overall results were largely consistent with those found for forest plants and animals. Some differences, however, were found when comparing macrofungal characteristics and levels of threat to macrofungi between Sweden and other European countries. Among the main threats to macrofungi in Sweden are modern forestry, the decrease of semi-natural open habitats as a result of changed land management practices, and, in southern Sweden, probably also air pollution.
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| 33. |
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| 34. |
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| 35. |
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| 36. |
- Steneck, R. S., et al.
(författare)
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Creation of a Gilded Trap by the High Economic Value of the Maine Lobster Fishery
- 2011
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 25:5, s. 904-912
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Tidskriftsartikel (refereegranskat)abstract
- Unsustainable fishing simplifies food chains and, as with aquaculture, can result in reliance on a few economically valuable species. This lack of diversity may increase risks of ecological and economic disruptions. Centuries of intense fishing have extirpated most apex predators in the Gulf of Maine (United States and Canada), effectively creating an American lobster (Homarus americanus) monoculture. Over the past 20 years, the economic diversity of marine resources harvested in Maine has declined by almost 70%. Today, over 80% of the value of Maine's fish and seafood landings is from highly abundant lobsters. Inflation-corrected income from lobsters in Maine has steadily increased by nearly 400% since 1985. Fisheries managers, policy makers, and fishers view this as a success. However, such lucrative monocultures increase the social and ecological consequences of future declines in lobsters. In southern New England, disease and stresses related to increases in ocean temperature resulted in more than a 70% decline in lobster abundance, prompting managers to propose closing that fishery. A similar collapse in Maine could fundamentally disrupt the social and economic foundation of its coast. We suggest the current success of Maine's lobster fishery is a gilded trap. Gilded traps are a type of social trap in which collective actions resulting from economically attractive opportunities outweigh concerns over associated social and ecological risks or consequences. Large financial gain creates a strong reinforcing feedback that deepens the trap. Avoiding or escaping gilded traps requires managing for increased biological and economic diversity. This is difficult to do prior to a crisis while financial incentives for maintaining the status quo are large. The long-term challenge is to shift fisheries management away from single species toward integrated social-ecological approaches that diversify local ecosystems, societies, and economies.
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| 37. |
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| 38. |
- Österblom, Henrik, et al.
(författare)
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Global Cooperation among Diverse Organizations to Reduce Illegal Fishing in the Southern Ocean
- 2012
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Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 26:4, s. 638-648
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Tidskriftsartikel (refereegranskat)abstract
- Illegal, unreported, and unregulated (IUU) fishing is prevalent globally and has detrimental effects on commercial fish stocks and nontarget species. Effective monitoring and enforcement aimed at reducing the level of IUU fishing in extensive, remote ocean fisheries requires international collaboration. Changes in trade and vessel activities further complicate enforcement. We used a web-based survey of governmental and nongovernmental organizations engaged in reducing IUU fishing in the Southern Ocean to collect information on interorganizational collaborations. We used social-network analyses to examine the nature of collaborations among the identified 117 organizations engaged in reducing IUU fishing. International collaboration improved the ability to control and manage harvest of commercially important toothfish (Dissostichus spp.) stocks and reduced bycatch of albatrosses (Diomedeidae) and petrels (Procellariidae) in longlines of IUU fishing vessels. The diverse group of surveyed organizations cooperated frequently, thereby making a wide range of resources available for improved detection of suspected IUU vessels and trade flows, cooperation aimed at prosecuting suspected offenders or developing new policy measures. Our results suggest the importance of a central agency for coordination and for maintaining commonly agreed-upon protocols for communication that facilities collaboration. Despite their differences, the surveyed organizations have developed common perceptions about key problems associated with IUU fishing. This has likely contributed to a sustained willingness to invest in collaborations. Our results show that successful international environmental governance can be accomplished through interorganizational collaborations. Such cooperation requires trust, continuous funding, and incentives for actors to participate.
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| 39. |
- Angeler, David
(författare)
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The perpetual state of emergency that sacrifices protected areas in a changing climate
- 2018
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 32, s. 905-915
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Tidskriftsartikel (refereegranskat)abstract
- A modern challenge for conservation biology is to assess the consequences of policies that adhere to assumptions of stationarity (e.g., historic norms) in an era of global environmental change. Such policies may result in unexpected and surprising levels of mitigation given future climate-change trajectories, especially as agriculture looks to protected areas to buffer against production losses during periods of environmental extremes. We assessed the potential impact of climate-change scenarios on the rates at which grasslands enrolled in the Conservation Reserve Program (CRP) are authorized for emergency harvesting (i.e., biomass removal) for agricultural use, which can occur when precipitation for the previous 4 months is below 40% of the normal or historical mean precipitation for that 4-month period. We developed and analyzed scenarios under the condition that policy will continue to operate under assumptions of stationarity, thereby authorizing emergency biomass harvesting solely as a function of precipitation departure from historic norms. Model projections showed the historical likelihood of authorizing emergency biomass harvesting in any given year in the northern Great Plains was 33.28% based on long-term weather records. Emergency biomass harvesting became the norm (>50% of years) in the scenario that reflected continued increases in emissions and a decrease in growing-season precipitation, and areas in the Great Plains with higher historical mean annual rainfall were disproportionately affected and were subject to a greater increase in emergency biomass removal. Emergency biomass harvesting decreased only in the scenario with rapid reductions in emissions. Our scenario-impact analysis indicated that biomass from lands enrolled in the CRP would be used primarily as a buffer for agriculture in an era of climatic change unless policy guidelines are adapted or climate-change projections significantly depart from the current consensus.
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| 40. |
- Bahram, Mohammad
(författare)
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Global mismatches in aboveground and belowground biodiversity
- 2019
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 33, s. 1187-1192
-
Tidskriftsartikel (refereegranskat)abstract
- Human activities are accelerating global biodiversity change and have resulted in severely threatened ecosystem services. A large proportion of terrestrial biodiversity is harbored by soil, but soil biodiversity has been omitted from many global biodiversity assessments and conservation actions, and understanding of global patterns of soil biodiversity remains limited. In particular, the extent to which hotspots and coldspots of aboveground and soil biodiversity overlap is not clear. We examined global patterns of these overlaps by mapping indices of aboveground (mammals, birds, amphibians, vascular plants) and soil (bacteria, fungi, macrofauna) biodiversity that we created using previously published data on species richness. Areas of mismatch between aboveground and soil biodiversity covered 27% of Earth's terrestrial surface. The temperate broadleaf and mixed forests biome had the highest proportion of grid cells with high aboveground biodiversity but low soil biodiversity, whereas the boreal and tundra biomes had intermediate soil biodiversity but low aboveground biodiversity. While more data on soil biodiversity are needed, both to cover geographic gaps and to include additional taxa, our results suggest that protecting aboveground biodiversity may not sufficiently reduce threats to soil biodiversity. Given the functional importance of soil biodiversity and the role of soils in human well-being, soil biodiversity should be considered further in policy agendas and conservation actions by adapting management practices to sustain soil biodiversity and considering soil biodiversity when designing protected areas.
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| 41. |
- Baranov, Viktor, et al.
(författare)
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Complex and nonlinear climate-driven changes in freshwater insect communities over 42 years
- 2020
-
Ingår i: Conservation Biology. - : John Wiley & Sons. - 0888-8892 .- 1523-1739. ; 34:5, s. 1241-1251
-
Tidskriftsartikel (refereegranskat)abstract
- The ongoing biodiversity crisis becomes evident in the widely observed decline in abundance and diversity of species, profound changes in community structure, and shifts in species' phenology. Insects are among the most affected groups, with documented decreases in abundance up to 76% in the last 25–30 years in some terrestrial ecosystems. Identifying the underlying drivers is a major obstacle as most ecosystems are affected by multiple stressors simultaneously and in situ measurements of environmental variables are often missing. In our study, we investigated a headwater stream belonging to the most common stream type in Germany located in a nature reserve with no major anthropogenic impacts except climate change. We used the most comprehensive quantitative long‐term data set on aquatic insects available, which includes weekly measurements of species‐level insect abundance, daily water temperature and stream discharge as well as measurements of additional physicochemical variables for a 42‐year period (1969–2010). Overall, water temperature increased by 1.88°C and discharge patterns changed significantly. These changes were accompanied by an 81.6% decline in insect abundance, but an increase in richness (+8.5%), Shannon diversity (+22.7%), evenness (+22.4%), and interannual turnover (+34%). Moreover, the community's trophic structure and phenology changed: the duration of emergence increased by 15.2 days, whereas the peak of emergence moved 13.4 days earlier. Additionally, we observed short‐term fluctuations (<5 years) in almost all metrics as well as complex and nonlinear responses of the community toward climate change that would have been missed by simply using snapshot data or shorter time series. Our results indicate that climate change has already altered biotic communities severely even in protected areas, where no other interacting stressors (pollution, habitat fragmentation, etc.) are present. This is a striking example of the scientific value of comprehensive long‐term data in capturing the complex responses of communities toward climate change.
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| 42. |
- Bartish, I. V., et al.
(författare)
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Anthropogenic threats to evolutionary heritage of angiosperms in the Netherlands through an increase in high-competition environments
- 2020
-
Ingår i: Conservation Biology. - : Blackwell Publishing Inc.. - 0888-8892 .- 1523-1739.
-
Tidskriftsartikel (refereegranskat)abstract
- Present biodiversity comprises the evolutionary heritage of Earth's epochs. Lineages from particular epochs are often found in particular habitats, but whether current habitat decline threatens the heritage from particular epochs is unknown. We hypothesized that within a given region, humans threaten specifically habitats that harbor lineages from a particular geological epoch. We expect so because humans threaten environments that dominated and lineages that diversified during these epochs. We devised a new approach to quantify, per habitat type, diversification of lineages from different epochs. For Netherlands, one of the floristically and ecologically best-studied regions, we quantified the decline of habitat types and species in the past century. We defined habitat types based on vegetation classification and used existing ranking of decline of vegetation classes and species. Currently, most declining habitat types and the group of red-listed species are characterized by increased diversification of lineages dating back to Paleogene, specifically to Paleocene-Eocene and Oligocene. Among vulnerable habitat types with large representation of lineages from these epochs were sublittoral and eulittoral zones of temperate seas and 2 types of nutrient-poor, open habitats. These losses of evolutionary heritage would go unnoticed with classical measures of evolutionary diversity. Loss of heritage from Paleocene-Eocene became unrelated to decline once low competition, shade tolerance, and low proportion of non-Apiaceae were accounted for, suggesting that these variables explain the loss of heritage from Paleocene-Eocene. Losses of heritage from Oligocene were partly explained by decline of habitat types occupied by weak competitors and shade-tolerant species. Our results suggest a so-far unappreciated human threat to evolutionary heritage: habitat decline threatens descendants from particular epochs. If the trends persist into the future uncontrolled, there may be no habitats within the region for many descendants of evolutionary ancient epochs, such as Paleogene.
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| 43. |
- Berggren, Åsa
(författare)
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Using long‐term data for a reintroduced population to empirically estimate future consequences of inbreeding
- 2021
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 35, s. 859-869
-
Tidskriftsartikel (refereegranskat)abstract
- Inbreeding depression is an important long-term threat to reintroduced populations. However, the strength of inbreeding depression is difficult to estimate in wild populations because pedigree data are inevitably incomplete and because good data are needed on survival and reproduction. Predicting future population consequences is especially difficult because this also requires projecting future inbreeding levels and their impacts on long-term population dynamics, which are subject to many uncertainties. We illustrate how such projections can be derived through Bayesian state-space modeling methods based on a 26-year data set for North Island Robins (Petroica longipes) reintroduced to Tiritiri Matangi Island in 1992. We used pedigree data to model increases in the average inbreeding level (F) over time based on kinship of possible breeding pairs and to estimate empirically Ne/N (effective/census population size). We used multiple imputation to model the unknown components of inbreeding coefficients, which allowed us to estimate effects of inbreeding on survival for all 1458 birds in the data set while modeling density dependence and environmental stochasticity. This modeling indicated that inbreeding reduced juvenile survival (1.83 lethal equivalents [SE 0.81]) and may have reduced subsequent adult survival (0.44 lethal equivalents [0.81]) but had no apparent effect on numbers of fledglings produced. Average inbreeding level increased to 0.10 (SE 0.001) as the population grew from 33 (0.3) to 160 (6) individuals over the 25 years, giving a urn:x-wiley:08888892:media:cobi13646:cobi13646-math-0001 ratio of 0.56 (0.01). Based on a model that also incorporated habitat regeneration, the population was projected to reach a maximum of 331–1144 birds (median 726) in 2130, then to begin a slow decline. Without inbreeding, the population would be expected stabilize at 887–1465 birds (median 1131). Such analysis, therefore, makes it possible to empirically derive the information needed for rational decisions about inbreeding management while accounting for multiple sources of uncertainty.
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| 44. |
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| 45. |
- Bodin, Örjan, et al.
(författare)
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Conservation Success as a Function of Good Alignment of Social and Ecological Structures and Processes
- 2014
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 28:5, s. 1371-1379
-
Tidskriftsartikel (refereegranskat)abstract
- How to create and adjust governing institutions so that they align (fit) with complex ecosystem processes and structures across scales is an issue of increasing concern in conservation. It is argued that lack of such social-ecological fit makes governance and conservation difficult, yet progress in explicitly defining and rigorously testing what constitutes a good fit has been limited. We used a novel modeling approach and data from case studies of fishery and forest conservation to empirically test presumed relationships between conservation outcomes and certain patterns of alignment of social-ecological interdependences. Our approach made it possible to analyze conservation outcome on a systems level while also providing information on how individual actors are positioned in the complex web of social-ecological interdependencies. We found that when actors who shared resources were also socially linked, conservation at the level of the whole social-ecological system was positively affected. When the scales at which individual actors used resources and the scale at which ecological resources were interconnected to other ecological resources were aligned through tightened feedback loops, conservation outcome was better than when they were not aligned. The analysis of individual actors' positions in the web of social-ecological interdependencies was helpful in understanding why a system has a certain level of social-ecological fit. Results of analysis of positions showed that different actors contributed in very different ways to achieve a certain fit and revealed some underlying difference between the actors, for example in terms of actors' varying rights to access and use different ecological resources.
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| 46. |
- Brunet, Jörg
(författare)
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Current Near-to-Nature Forest Management Effects on Functional Trait Composition of Saproxylic Beetles in Beech Forests
- 2013
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 27, s. 605-614
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Tidskriftsartikel (refereegranskat)abstract
- With the aim of wood production with negligible negative effects on biodiversity and ecosystem processes, a silvicultural practice of selective logging with natural regeneration has been implemented in European beech forests (Fagus sylvatica) during the last decades. Despite this near-to-nature strategy, species richness of various taxa is lower in these forests than in unmanaged forests. To develop guidelines to minimize the fundamental weaknesses in the current practice, we linked functional traits of saproxylic beetle species to ecosystem characteristics. We used continental-scale data from 8 European countries and regional-scale data from a large forest in southern Germany and forest-stand variables that represented a gradient of intensity of forest use to evaluate the effect of current near-to-nature management strategies on the functional diversity of saproxylic beetles. Forest-stand variables did not have a statistically significant effect on overall functional diversity, but they did significantly affect community mean and diversity of single functional traits. As the amount of dead wood increased the composition of assemblages shifted toward dominance of larger species and species preferring dead wood of large diameter and in advanced stages of decay. The mean amount of dead wood across plots in which most species occurred was from 20 to 60 m3/ha. Species occurring in plots with mean dead wood >60 m3/ha were consistently those inhabiting dead wood of large diameter and in advanced stages of decay. On the basis of our results, to make current wood-production practices in beech forests throughout Europe more conservation oriented (i.e., promoting biodiversity and ecosystem functioning), we recommend increasing the amount of dead wood to >20 m3/ha; not removing dead wood of large diameter (50 cm) and allowing more dead wood in advanced stages of decomposition to develop; and designating strict forest reserves, with their exceptionally high amounts of dead wood, that would serve as refuges for and sources of saproxylic habitat specialists.
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| 47. |
- Chaigneau, Tomas, et al.
(författare)
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Incorporating basic needs to reconcile poverty and ecosystem services
- 2019
-
Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 33:3, s. 655-664
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Tidskriftsartikel (refereegranskat)abstract
- Conservation managers frequently face the challenge of protecting and sustaining biodiversity without producing detrimental outcomes for (often poor) human populations that depend on ecosystem services for their well-being. However, mutually beneficial solutions are often elusive and can mask trade-offs and negative outcomes for people. To deal with such trade-offs, ecological and social thresholds need to be identified to determine the acceptable solution space for conservation. Although human well-being as a concept has recently gained prominence, conservationists still lack tools to evaluate how their actions affect it in a given context. We applied the theory of human needs to conservation by building on an extensive historical application of need approaches in international development. In an innovative participatory method that included focus groups and household surveys, we evaluated how human needs are met based on locally relevant thresholds. We then established connections between human needs and ecosystem services through key-informant focus groups. We applied our method in coastal East Africa to identify households that would not be able to meet their basic needs and to uncover the role of ecosystem services in meeting these. This enabled us to identify how benefits derived from the environment were contributing to meeting basic needs and to consider potential repercussions that could arise through changes to ecosystem service provision. We suggest our approach can help conservationists and planners balance poverty alleviation and biodiversity protection and ensure conservation measures do not, at the very least, cause serious harm to individuals. We further argue it can be used as a basis for monitoring the impacts of conservation on multidimensional poverty.
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| 48. |
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| 49. |
- Chapron, Guillaume, et al.
(författare)
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Testing a global standard for quantifying species recovery and assessing conservation impact
- 2021
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Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 35, s. 1833-1849
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Tidskriftsartikel (refereegranskat)abstract
- Recognizing the imperative to evaluate species recovery and conservation impact, in 2012 the International Union for Conservation of Nature (IUCN) called for development of a "Green List of Species" (now the IUCN Green Status of Species). A draft Green Status framework for assessing species' progress toward recovery, published in 2018, proposed 2 separate but interlinked components: a standardized method (i.e., measurement against benchmarks of species' viability, functionality, and preimpact distribution) to determine current species recovery status (herein species recovery score) and application of that method to estimate past and potential future impacts of conservation based on 4 metrics (conservation legacy, conservation dependence, conservation gain, and recovery potential). We tested the framework with 181 species representing diverse taxa, life histories, biomes, and IUCN Red List categories (extinction risk). Based on the observed distribution of species' recovery scores, we propose the following species recovery categories: fully recovered, slightly depleted, moderately depleted, largely depleted, critically depleted, extinct in the wild, and indeterminate. Fifty-nine percent of tested species were considered largely or critically depleted. Although there was a negative relationship between extinction risk and species recovery score, variation was considerable. Some species in lower risk categories were assessed as farther from recovery than those at higher risk. This emphasizes that species recovery is conceptually different from extinction risk and reinforces the utility of the IUCN Green Status of Species to more fully understand species conservation status. Although extinction risk did not predict conservation legacy, conservation dependence, or conservation gain, it was positively correlated with recovery potential. Only 1.7% of tested species were categorized as zero across all 4 of these conservation impact metrics, indicating that conservation has, or will, play a role in improving or maintaining species status for the vast majority of these species. Based on our results, we devised an updated assessment framework that introduces the option of using a dynamic baseline to assess future impacts of conservation over the short term to avoid misleading results which were generated in a small number of cases, and redefines short term as 10 years to better align with conservation planning. These changes are reflected in the IUCN Green Status of Species Standard.
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| 50. |
- Chapron, Guillaume
(författare)
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The place of nature in conservation conflicts
- 2020
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Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 34, s. 795-802
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Tidskriftsartikel (refereegranskat)abstract
- Conservation conflicts are gaining importance in contemporary conservation scholarship such that conservation may have entered a conflict hype. We attempted to uncover and deconstruct the normative assumptions behind such studies by raising several questions: what are conservation conflicts, what justifies the attention they receive, do conservation-conflict studies limit wildlife conservation, is scientific knowledge stacked against wildlife in conservation conflicts, do conservation-conflict studies adopt a specific view of democracy, can laws be used to force conservation outcomes, why is flexibility needed in managing conservation conflicts, can conservation conflicts be managed by promoting tolerance, and who needs to compromise in conservation conflicts? We suggest that many of the intellectual premises in the field may defang conservation and prevent it from truly addressing the current conservation crisis as it accelerates. By framing conservation conflicts as conflicts between people about wildlife or nature, the field insidiously transfers guilt, whereby human activities are no longer blamed for causing species decline and extinctions but conservation is instead blamed for causing social conflicts. When the focus is on mitigating social conflicts without limiting in any powerful way human activities damaging to nature, conservation-conflict studies risk keeping conservation within the limits of human activities, instead of keeping human activities within the limits of nature. For conservation to successfully stop the biodiversity crisis, we suggest the alternative goal of recognizing nature's right to existence to maintenance of ecological functions and evolutionary processes. Nature being a rights bearer or legal person would imply its needs must be explicitly taken into account in conflict adjudication. If, even in conservation, nature's interests come second to human interests, it may be no surprise that conservation cannot succeed.
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