There is a world somewhere between reality and fiction. Although ignored by many, it is very real and so are those living in it. This forum is about the natural world. Here, wild animals will be heard and respected. The forum offers a glimpse into an unknown world as well as a room with a view on the present and the future. Anyone able to speak on behalf of those living in the emerald forest and the deep blue sea is invited to join.
--- Peter Broekhuijsen ---

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India Rishi Offline
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#16

Pre-feasibility Study on the Possible Restoration of Caspian Tigers in the AmuDarya Delta
https://drive.google.com/file/d/0B69B_ZI...ZfbmM/view )
Everything not saved will be lost. - Nintendo 

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India Rishi Offline
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#17

14th Lion Population Estimation Report, 2015
https://drive.google.com/file/d/0B69B_ZI...YzSzA/view )
Everything not saved will be lost. - Nintendo 

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India Rishi Offline
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#18

Drawdown: The Most Comprehensive Plan Ever Proposed to Reverse Global Warming
https://books.google.co.in/books?id=TZXZ...&q&f=false )
Everything not saved will be lost. - Nintendo 

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Netherlands peter Offline
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#19

Good thread. My proposal is to post as many links to studies and articles as possible. Talk to Tigerluver first, as he is a biologist and has access to more information than we have.
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United Kingdom Sully Offline
Ecology and Conservation
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#20
( This post was last modified: 01-25-2020, 09:47 PM by Sully )

Rewilding with large herbivores: Positive direct and delayed effects of carrion on plant and arthropod communities

Abstract

Carrion of large animals is an extremely nutrient rich, ephemeral resource that is essential for many species, but is scarce in the anthropogenic Western-European landscape due to legislative restrictions. Rewilding, a novel conservation strategy that aims at restoring natural processes with minimal human intervention, is increasing in popularity and could lead to increased carrion availability in the landscape. It is therefore important to understand the effects of carrion on biodiversity. We investigated the direct and delayed (five months) effects of red deer (Cervus elaphus) carcasses on plants and arthropods in the Oostvaardersplassen, the Netherlands, one of the oldest rewilding sites in Europe. Specifically, we tested whether carrion has a positive direct effect on the abundances and diversity of various arthropod functional groups, as well as a delayed effect on the vegetation and arthropods through the increased nutrient availability. During the active decomposition stage in spring, we, not surprisingly, observed higher abundances of carrion associated species (scavengers and their specialized predators) at the carrion sites than at control sites without carrion, but no higher abundances of predators or detritivores. In late summer, after near-complete decomposition, plant biomass was five times higher, and nutritional plant quality (CNeutral ratio) was higher at the carrion sites than at the control sites. Arthropod abundance and diversity were also manifold higher, owing to higher numbers of herbivorous and predatory species. Regression analysis showed that abundances of herbivores and detritivores were positively related to plant biomass, and predator abundances were positively related to abundances of herbivores and detritivores, suggesting bottom-up effects propagating through the food chain. Our results show that even in a naturally nutrient-rich ecosystem like the Oostvaardersplassen, carrion can have strong positive effects on local plant biomass and nutritional quality and arthropod abundances, lasting the whole growing season. We found evidence that these effects were first directly caused by the presence of carrion, and later by the enhanced nutrient availability in the soil. This highlights the importance of the indirect pathways by which carrion can structure arthropod communities.
"When the tiger stalks the jungle like the lowering clouds of a thunderstorm, the leopard moves as silently as mist drifting on a dawn wind." -Indian proverb
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United Kingdom Sully Offline
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#21

Macroevolutionary convergence connects morphological form to ecological function in birds

Abstract

Animals have diversified into a bewildering variety of morphological forms exploiting a complex configuration of trophic niches. Their morphological diversity is widely used as an index of ecosystem function, but the extent to which animal traits predict trophic niches and associated ecological processes is unclear. Here we use the measurements of nine key morphological traits for >99% bird species to show that avian trophic diversity is described by a trait space with four dimensions. The position of species within this space maps with 70–85% accuracy onto major niche axes, including trophic level, dietary resource type and finer-scale variation in foraging behaviour. Phylogenetic analyses reveal that these form–function associations reflect convergence towards predictable trait combinations, indicating that morphological variation is organized into a limited set of dimensions by evolutionary adaptation. Our results establish the minimum dimensionality required for avian functional traits to predict subtle variation in trophic niches and provide a global framework for exploring the origin, function and conservation of bird diversity.
"When the tiger stalks the jungle like the lowering clouds of a thunderstorm, the leopard moves as silently as mist drifting on a dawn wind." -Indian proverb
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United Kingdom Sully Offline
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#22

Assessing the growth and climate sensitivity of secondary forests in highly deforested Amazonian landscapes

Abstract:

Tropical forests hold 30% of Earth’s terrestrial carbon and at least 60% of its terrestrial biodiversity, but forest loss and degradation are jeopardizing these ecosystems. Although the regrowth of secondary forests has the potential to offset some of the losses of carbon and biodiversity, it remains unclear if secondary regeneration will be affected by climate changes such as higher temperatures and more frequent extreme droughts. We used a data set of 10 repeated forest inventories spanning two decades (1999–2017) to investigate carbon and tree species recovery and how climate and landscape context influence carbon dynamics in an older secondary forest located in one of the oldest post‐Columbian agricultural frontiers in the Brazilian Amazon. Carbon accumulation averaged 1.08 Mg·ha−1·yr−1, and species richness was effectively constant over the studied period. Moreover, we provide evidence that secondary forests are vulnerable to drought stress: Carbon balance and growth rates were lower in drier periods. This contrasts with drought responses in primary forests, where changes in carbon dynamics are driven by increased stem mortality. These results highlight an important climate change–vegetation feedback, whereby the increasing dry‐season lengths being observed across parts of Amazonia may reduce the effectiveness of secondary forests in sequestering carbon and mitigating climate change. In addition, the current rate of forest regrowth in this region was low compared with previous pan‐tropical and Amazonian assessments—our secondary forests reached just 41.1% of the average carbon and 56% of the tree diversity in the nearest primary forests—suggesting that these areas are unlikely to return to their original levels on politically meaningful time scales.
"When the tiger stalks the jungle like the lowering clouds of a thunderstorm, the leopard moves as silently as mist drifting on a dawn wind." -Indian proverb
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United Kingdom Sully Offline
Ecology and Conservation
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#23

Predator-Specific Mortality of Pronghorn on Yellowstone's Northern Range

Abstract

Yellowstone National Park supports a small population (<300) of pronghorn (Antilocapra americana). Some individuals migrate during summer to areas characterized by reduced visibility, mixed habitat types, and a diverse predator community. Across areas selected by migratory and nonmigratory pronghorn, we documented cause-specific mortality of adults and fawns and assessed relative risk of predation by various predators. Coyotes (Canis latrans) accounted for 56% of adult predation and up to 79% of fawn predation. Cougars (Puma concolor) and wolves (Canis lupus) accounted for additional predation of adults, while cougars, black bears (Ursus americanus), and Golden Eagles (Aquila chrysaetos) were documented killing fawns on rare occasions. Our results suggest that even when pronghorn are in the presence of multiple predator species, coyote predation on adults and fawns may predominate for populations inhabiting shrubsteppe habitat. However, the risk of predation by sympatric predators, particularly cougars, may be high for female pronghorn selecting mixed cover types during migration or for birthing purposes. While the direct effect of wolves on overall mortality was low, wolves may indirectly influence survival rates of adult females and fawns by altering the behavior and space use of sympatric predators, particularly coyotes.
"When the tiger stalks the jungle like the lowering clouds of a thunderstorm, the leopard moves as silently as mist drifting on a dawn wind." -Indian proverb
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United Kingdom Sully Offline
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#24

Parallel declines in abundance of insects and insectivorous birds in Denmark over 22 years

Abstract



  1. Farmers in most western countries have increased use of fertilizer and pesticides with impact on wild animals and plants, including the abundance of insects and their predators.
  2. I used 1,375 surveys of insects killed on car windscreens as a measure of insect abundance during 1997–2017 at two transects in Denmark. I cross‐validated this method against three other methods for sampling insect abundance, and I investigated the effects of this measure of insect abundance on the abundance of breeding insectivorous birds.
  3. The abundance of flying insects was quantified using a windscreen resulting in reductions of 80% and 97% at two transects of 1.2 km and 25 km, respectively, according to general additive mixed model. Insect abundance increased with time of day, temperature, and June date, but decreased with wind resulting in a reduction by 54%. The abundance of insects killed on a car windscreen was strongly positively correlated with the abundance of insects caught in sweep nets and on sticky plates in the same study areas and at the same time as when insects were sampled using windscreens. The decline in abundance of insects on windscreens predicted the rate at which barn swallows Hirundo rustica fed their nestlings, even when controlling statistically for time of day, weather, and age and number of nestlings. The abundance of breeding pairs of three species of aerially insectivorous birds was positively correlated with the abundance of insects killed on windscreens at the same time in the same study area. This suggests a link between two trophic levels as affected by the temporal reduction in the abundance of flying insects.
  4. These findings are consistent with recent dramatic declines in insect abundance in Europe and North America with consequences for the rate of food provisioning of barn swallow offspring, the abundance of aerially insectivorous birds and bottom‐up trophic cascades.
"When the tiger stalks the jungle like the lowering clouds of a thunderstorm, the leopard moves as silently as mist drifting on a dawn wind." -Indian proverb
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United Kingdom Sully Offline
Ecology and Conservation
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#25

Geographical analysis of the Javan deer distribution in Indonesia and priorities for landscape conservation

Abstract

Javan deer (Rusa timorensis) is a protected species in Indonesia and considered to be vulnerable under IUCN list. Nevertheless, its native geographic distribution remains unclear, and the impact of abiotic and biotic factors on this species are mostly unknown. We predicted the potential range of Javan deer in Java and Bali Islands using ten environmental variables, occurrence data of native (76 before 1965, and 653 after 1965) and introduced populations (559), and MaxEnt modelling. We evaluated the effects of habitat loss due to current land use, ecosystem availability, and importance of Indonesian protected areas into the models. Our predictive map significantly improved the IUCN assessment and described for the first time the spread of Javan deer out of its native range within Indonesia. The model of environmental suitability estimated a potential of 3,784.43 km2 natural occurrence in Java and Bali and 36,352.61 km2 for introduced populations in protected areas of West Nusa Tenggara to Papua. The most critical environmental predictors for both populations are the mean annual precipitation and the conservation status of land. Then, 45.66 % of the distribution of native populations overlaps with protected areas, 18.96 % with production forests, 11.07 % with non-protected areas, 10.10 % with limited production forests and 4.20 % with industrial oil palm plantations. Only 22.88 % of the distribution of introduced populations overlaps with protected areas. Our study provides reliable information on places where conservation efforts must be prioritized, both inside and outside the protected area network, to safeguard one of the remaining Indonesian large deer.
"When the tiger stalks the jungle like the lowering clouds of a thunderstorm, the leopard moves as silently as mist drifting on a dawn wind." -Indian proverb
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United Kingdom Sully Offline
Ecology and Conservation
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#26

Global synthesis of conservation studies reveals the importance of small habitat patches for biodiversity

Abstract

Island biogeography theory posits that species richness increases with island size and decreases with isolation. This logic underpins much conservation policy and regulation, with preference given to conserving large, highly connected areas, and relative ambivalence shown toward protecting small, isolated habitat patches. We undertook a global synthesis of the relationship between the conservation value of habitat patches and their size and isolation, based on 31 systematic conservation planning studies across four continents. We found that small, isolated patches are inordinately important for biodiversity conservation. Our results provide a powerful argument for redressing the neglect of small, isolated habitat patches, for urgently prioritizing their restoration, and for avoiding simplistic application of island biogeography theory in conservation decisions.
"When the tiger stalks the jungle like the lowering clouds of a thunderstorm, the leopard moves as silently as mist drifting on a dawn wind." -Indian proverb
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United Kingdom Sully Offline
Ecology and Conservation
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#27

The Global Flood Protection Benefits of Mangroves

Abstract

Coastal flood risks are rising rapidly. We provide high resolution estimates of the economic value of mangroves forests for flood risk reduction every 20 km worldwide. We develop a probabilistic, process-based valuation of the effects of mangroves on averting damages to people and property. We couple spatially-explicit 2-D hydrodynamic analyses with economic models, and find that mangroves provide flood protection benefits exceeding $US 65 billion per year. If mangroves were lost, 15 million more people would be flooded annually across the world. Some of the nations that receive the greatest economic benefits include the USA, China, India and Mexico. Vietnam, India and Bangladesh receive the greatest benefits in terms of people protected. Many (>45) 20-km coastal stretches particularly those near cities receive more than $US 250 million annually in flood protection benefits from mangroves. These results demonstrate the value of mangroves as natural coastal defenses at global, national and local scales, which can inform incentives for mangrove conservation and restoration in development, climate adaptation, disaster risk reduction and insurance.
"When the tiger stalks the jungle like the lowering clouds of a thunderstorm, the leopard moves as silently as mist drifting on a dawn wind." -Indian proverb
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United Kingdom Sully Offline
Ecology and Conservation
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#28

Local Adaptation to Biotic Interactions: A Meta-analysis across Latitudes 

Abstract

Adaptation to local conditions can increase species’ geographic distributions and rates of diversification, but which components of the environment commonly drive local adaptation—particularly the importance of biotic interactions—is unclear. Biotic interactions should drive local adaptation when they impose consistent divergent selection; if this is common, we expect transplant experiments to detect more frequent and stronger local adaptation when biotic interactions are left intact. We tested this hypothesis using a meta-analysis of transplant experiments from >125 studies (mostly of plants). Overall, local adaptation was common, and biotic interactions affected fitness. Nevertheless, local adaptation was neither more common nor stronger when biotic interactions were left intact, either between experimental treatments within studies (control vs. biotic interactions experimentally manipulated) or between studies that used natural versus biotically altered transplant environments. However, the effect of ameliorating negative interactions varied with latitude, suggesting that interactions may promote local adaptation more often in tropical than in temperate ecosystems, although few tropical studies were available to test this. Our results suggest that biotic interactions often fail to drive local adaptation even though they strongly affect fitness, perhaps because temperate biotic environments are unpredictable at the spatiotemporal scales required for local adaptation.
"When the tiger stalks the jungle like the lowering clouds of a thunderstorm, the leopard moves as silently as mist drifting on a dawn wind." -Indian proverb
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United Kingdom Sully Offline
Ecology and Conservation
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#29

Biodiversity and climate change: size matters, and it depends on the region

World temperatures have reached unprecedented levels in the last years and the consequences of climate change are clearly perceptible. Glaciers are melting, the frequency and magnitude of extreme weather events is increasing… In silence, biodiversity is paying the price, and a significant proportion of species is already declining.
Sometimes life finds a way to adapt, however: some species are able to shift their distribution range poleward, some may shift their activity period, while others would shrink theirs. Is this the result of an adaptive strategy to avoid overheating? During my PhD, I showed that this phenomenon was mostly true in regions that are already constrained by heat such as the Mediterranean region in France, but not in the rest of the country.
Bergmann’s rule
Biogeography, a science aimed at describing and explaining the geographic distribution of living beings, is a poorly known domain. Yet, it is a long-standing issue whose founding fathers such as Charles Darwin and Carl Bergmann were under the spotlight during the 19th century. The former is the author of the famous theory of evolution, while the latter has stated the biogeographic principle carrying his name: Bergmann’s rule.

*This image is copyright of its original author
Carl Bergmann described the rule proposing that warm-blooded animals living under high latitudes tend to be larger than their counterparts under lower latitudes. Does this rule apply to the context of climate warming?

Under high latitudes, corresponding to cold regions, animals tend to be larger than those living under lower latitudes. This trend mostly apply to endotherms: birds and mammals. Specifically, body size differences can be observed within groups of species (order or family) such as bears. Take a polar bear for instance, which is much larger than other bear species.
While there are many exceptions, recent biogeographic studies have shown that Bergmann’s rule mostly apply at the within-species scale. Individuals of a given species such as the European robin, living toward the hot edge of their distribution range tend to be smaller than those living at the cold edge. This phenomenon is related to the efficiency of thermoregulation, the capacity to maintain or lose body heat. Larger individuals, being able to better conserve body heat, were selected in cold regions as a result of a lower risk of hypothermia. Conversely, smaller individuals were selected in warmer latitudes since they are less likely to suffer from overheat.
Biogeography is fascinating, but does it even matter in our society? The Earth’s climate is getting warmer and its impact can be already be perceived through biodiversity. Wildlife is not only important to human kind for its entertaining aspect. Not only for beauty, legacy, or passion. In short, not only for its intrinsic value. It is also valuable for the service given to civilisation. Agricultural productivity and food safety, for instance through pollination. Discovery of new substances with medical or industrial application, welfare and health, ecotourism, technological development… The potential impacts are both diverse and immense – it’s not something just for ecologists.
Species’ responses to climate change
When species seek to survive to a changing world, they can respond to climate change through three dimensions: space, time and physiology. Any strategy can help to cope with changing conditions – for example, running away from the heat.
  • Through space: we can observe poleward shifts in species’ geographic distributions.
  • Through time: species shift their activity periods. Cherry trees bloom earlier in the spring. Marmots emerge sooner from their hibernation.
  • Through physiology and phenotype: species modify their metabolism, which can be expressed by changes in morphology and body size.
Shrinking body size would allow animals to improve their heat loss efficiency. This is the application of Bergmann’s rule through time, to the context of temporal change in climatic conditions. The topic is presented in a humorous three-minute musical clip:

The proposal of an application of Bergmann’s rule through time is recent, and body size response to climate change is still poorly understood. Do animals become smaller in every places? Is it actually an adaptive response for a better thermoregulation?
Our research team based at the Museum of Natural History in Paris attempted to provide an answer using citizen science data from the French bird ringing programme, based on more than 30 years of bird measurements all across the country. The results were published in Global Ecology and Biogeography, and showed that young birds were smaller in hotter springs, but only at the warmest sites around the Mediterranean region where the heat is already a constraining factor. Conversely in the remaining sites, more constrained by cold during spring, juveniles were larger in warmer years. In this context, higher temperatures would enable fledgling birds to save the energy that is usually spent to maintain their heat, and allocate it to cellular division and body growth instead.
Direct and indirect effects
These contrasting effects of warming may be related to direct effects on thermoregulation, but also to indirect effects on ecosystem productivity and food availability. A local increase in temperature at the warmest places would increase aridity, which would harm plant growth and hence insect abundance, which constitute juvenile birds’ favourite food. The opposite pattern would be observed at the coldest site: warmer conditions would stimulate plant production and insect activity, providing more food available for bird consumption.
Climate warming may induce animal body size decline, but at places that are already constrained by heat. There is no evidence that this response is an adaptation. The latest studies, published in Nature Communications and in Proceeding of the Royal Society of London, suggest that shrinking body size may be the result of a non-adaptive response to environmental degradation instead. Another warning in the face of an ongoing climate crisis.
"When the tiger stalks the jungle like the lowering clouds of a thunderstorm, the leopard moves as silently as mist drifting on a dawn wind." -Indian proverb
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United Kingdom Sully Offline
Ecology and Conservation
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#30

On herbivore classification

"Hofmann and Stewart (1972) classified as: 1) Bulk and Roughage Feeders or Grazers that select diets containing < 25% browse; 2) Concentrate Selectors or Browsers that select diets containing at least 75% fruits, dicot foliage, and tree and shrub stems and foliage; or 3) Intermediate or Mixed Feeders that select both grasses and browses.  Using this scheme to classify 65 ruminants on 4 continents, Hofmann (1989) found that 25% were grazers, 40% were browser/fruit-eaters, and 35% were mixed feeders.  Many have argued that tree and shrub foliage and stems should not be considered “concentrates”, because they are heavily defended by plant secondary compounds (Robbins et al. 1995) and lignin, and thus fruit selectors (true concentrates) and browsers should form separate categories (Bodmer 1990).  Others suggest that these categories only reflect trends in body mass, because smaller herbivores tend to select concentrates whereas larger ones tend to choose roughage or grass (Gordon and Illius 1994, Robbins et al. 1995).  For example, in tropical areas frugivores average 24 kg, browsers 394 kg, intermediate feeders 695 kg, and Grazers 670 Kg (Bodmer 1990)."

from:

Grazers and Browsers: How Digestive Morphology Affects Diet Selection
"When the tiger stalks the jungle like the lowering clouds of a thunderstorm, the leopard moves as silently as mist drifting on a dawn wind." -Indian proverb
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