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1.
PeerJ ; 11: e15746, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37872949

RESUMO

Background: The Kashmir red deer or Hangul (Cervus hanglu hanglu) is the only Tarim red deer species endemic to India. With a current estimated population size of fewer than 200 individuals, this critically endangered species is confined to the greater Dachigam landscape in Jammu and Kashmir. Poaching, habitat loss and fragmentation, resource competition with livestock, and small population size are the major conservation challenges for this species. Methods: Blood sampling was conducted from two wild Hangul individuals during radio-collaring operations at Dachigam National Park, Kashmir in 2013 and 2020, respectively. Using next-generation sequencing approach, we sequenced the 16,351 bp long mitogenome of two wild-caught Hangul individuals (1 M:1 F at ~14× and ~10× coverage, respectively) from Dachigam National Park. Results: The annotated sequences were identical with an AT-rich composition, including 13 protein-coding genes (11,354 bp), 22 tRNA genes (1,515 bp), two ribosomal genes (2,526 bp) and a non-coding control region (917 bp) in a conserved order like other red deer species. Bayesian phylogenetic reconstruction of the red deer complex revealed two major groups: the elaphoid and the wapitoid clades. Hangul formed a distinct clade with its other subspecies C. hanglu yarkandensis and is sister to the Hungarian red deer (C. elaphus hippelaphus). Divergence time analyses suggested that the Tarim deer species group separated ~1.55 Mya from their common ancestors and Hangul diverged ~0.75 Mya from closely related C. yarkandensis, corroborating with the known paleobiogeographic events related to refugia during glaciations in the Pleistocene era. This study provides baseline information on Hangul mitogenome for further research on phylogeography and other population parameters and helps in developing suitable conservation plans for this species.


Assuntos
Cervos , Animais , Filogenia , Teorema de Bayes , Cervos/genética , Evolução Biológica , Filogeografia
2.
Ecol Appl ; 33(6): e2891, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37232432

RESUMO

There is an increasing need to understand how animals respond to modifications of their habitat following landscape-scale disturbances such as wildfire or timber harvest. Such disturbances can promote increased use by herbivores due to changes in plant community structure that improve forage conditions, but can also cause avoidance if other habitat functions provided by cover are substantially reduced or eliminated. Quantifying the total effects of these disturbances, however, is challenging because they may not fully be apparent unless observed at successional timescales. Further, the effects of disturbances that improve habitat quality may be density dependent, such that the benefits are (1) less valuable to high-density populations because the per-capita benefits are reduced when shared among more users or, alternatively, (2) more valuable to animals living in high densities because resources may be more depleted from the greater intraspecific competition. We used 30 years of telemetry data on elk occurring at two distinct population densities to quantify changes in space use at diel, monthly, and successional timescales following timber harvest. Elk selected logged areas at night only, with selection strongest during midsummer, and peak selection occurring 14 years post harvest, but persisting for 26-33 years. This pattern of increased selection at night following a reduction in overhead canopy cover is consistent with elk exploiting improved nutritional conditions for foraging. The magnitude of selection for logged areas was 73% higher for elk at low population density, consistent with predictions from the ideal free distribution. Yet elk avoided these same areas during daytime for up to 28 years post logging and instead selected untreated forest, suggesting a role for cover to meet other life history requirements. Our results demonstrate that while landscape-scale disturbances can lead to increased selection by large herbivores and suggest that the improvement in foraging conditions can persist over short-term successional timescales, the magnitude of the benefits may not be equal across population densities. Further, the enduring avoidance of logging treatments during the daytime indicates a need for structurally intact forests and suggests that a mosaic of forest patches of varying successional stages and structural completeness is likely to be the most beneficial to large herbivores.


Assuntos
Cervos , Florestas , Herbivoria , Incêndios Florestais , Animais , Cervos/fisiologia , Densidade Demográfica
3.
Ecol Appl ; 33(4): e2836, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36890426

RESUMO

Forests are major carbon (C) sinks, but their ability to sequester C and thus mitigate climate change, varies with the environment, disturbance regime, and biotic interactions. Herbivory by invasive, nonnative ungulates can have profound ecosystem effects, yet its consequences for forest C stocks remain poorly understood. We determined the impact of invasive ungulates on C pools, both above- and belowground (to 30 cm), and on forest structure and diversity using 26 paired long-term (>20 years) ungulate exclosures and adjacent unfenced control plots located in native temperate rainforests across New Zealand, spanning 36-41° S. Total ecosystem C was similar between ungulate exclosure (299.93 ± 25.94 Mg C ha-1 ) and unfenced control (324.60 ± 38.39 Mg C ha-1 ) plots. Most (60%) variation in total ecosystem C was explained by the biomass of the largest tree (mean diameter at breast height [dbh]: 88 cm) within each plot. Ungulate exclusion increased the abundance and diversity of saplings and small trees (dbh ≥2.5, <10 cm) compared with unfenced controls, but these accounted for ~5% of total ecosystem C, demonstrating that a few, large trees dominate the total forest ecosystem C but are unaffected by invasive ungulates at a timescale of 20-50 years. However, changes in understory C pools, species composition, and functional diversity did occur following long-term ungulate exclusion. Our findings suggest that, although the removal of invasive herbivores may not affect total forest C at the decadal scale, major shifts in the diversity and composition of regenerating species will have longer term consequences for ecosystem processes and forest C.


Assuntos
Cervos , Árvores , Animais , Ecossistema , Carbono , Florestas
4.
Biology (Basel) ; 11(11)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36358308

RESUMO

Increasing populations of large herbivores have caused environmental damage around the world, and it is necessary to improve population management strategies. Culling is a traditional management method. Antlerless deer proportions, consisting of adult female deer and fawn in Cervidae in wildlife statistics, are directly related to population increases; thus, the culling-based removal of individuals from habitats and the removal of these antlerless individuals by game hunting and nuisance control might be effective approaches for reducing population sizes. We evaluated the effectiveness of antlerless culling on 17-year density trends in the sika deer (Cervus nippon) population across an area of 1175 km2 in Fukuoka Prefecture (Japan). In 11 out of 47 grids (area measuring 5 by 5 km), the densities of sika deer tended to decline; meanwhile, in the remaining 36 grids, the densities increased. These density trends were explained by changes in the proportion of antlerless culling, as the densities declined with increasing proportions of antlerless deer. The results affirm the theory that antlerless culling is effective in population management; it is posited that antlerless-biased culling could be a crucial measure in managing overabundant populations of herbivores, contributing to more effective conservation of forest environments.

5.
Ecol Evol ; 12(10): e9389, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36254298

RESUMO

The behavioral mechanisms by which predators encounter prey are poorly resolved. In particular, the extent to which predators engage in active search for prey versus incidentally encountering them has not been well studied in many systems and particularly not for neonate prey during the birth pulse. Parturition of many large herbivores occurs during a short and predictable temporal window in which young are highly vulnerable to predation. Our study aims to determine how a suite of carnivores responds to the seasonal pulse of newborn ungulates using contemporaneous global positioning system (GPS) locations of four species of predators and two species of prey. We used step-selection functions to assess whether coyotes, cougars, black bears, and bobcats encountered parturient adult female ungulates more often than expected by chance in a low-density population of mule deer and a high-density population of elk. We then assessed whether the carnivore species that encountered parturient prey more often than expected by chance did so by shifting their habitat use toward areas with a high probability of encountering neonates. None of the four carnivore species encountered GPS-collared parturient mule deer more often than expected by chance. By contrast, we determined that cougar and male bear movements positioned them in the proximity of GPS-collared parturient elk more often than expected by chance which may provide evidence of searching behavior. Although both male bears and cougars exhibited behavior consistent with active search for neonates, only male bears used elk parturition habitat in a way that dynamically tracked the phenology of the elk birth pulse suggesting that maximizing encounters with juvenile elk was a motivation when selecting resources. Our results suggest that there is high interspecific and intersexual variability in foraging strategies among large mammalian predators and their prey.

6.
Ecol Evol ; 12(5): e8879, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35516419

RESUMO

In mammals, the gut microbiome is vertically transmitted during maternal lactation at birth. In this study, we investigated the gut microbiome and diets of muskox, a large herbivore inhabiting in the high Arctic. We compared the microbiota composition using bacterial 16S rRNA gene sequencing and diets using stable isotope analysis of muskox feces of six female adults and four calves on Ella Island, East Greenland. Firmicutes were the most abundant bacterial phylum in both the adults and calves, comprising 94.36% and 94.03%, respectively. Significant differences were observed in the relative abundance of the two Firmicutes families. The adults were primarily dominated by Ruminococcaceae (73.90%), and the calves were dominated by both Ruminococcaceae (56.25%) and Lachnospiraceae (24.00%). Stable isotope analysis of the feces in the study area revealed that both adults and calves had similar ranges of 13C and 15N, likely derived from the dominant diet plants. Despite their similar diets, the different gut microbiome compositions in muskox adults and calves indicate that the gut microbiome of the calves may not be fully colonized to the extent of that of the adults.

7.
Ecol Evol ; 12(4): e8828, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35475176

RESUMO

Fire and herbivores alter vegetation structure and function. Future fire activity is predicted to increase, and quantifying changes in vegetation communities arising from post-fire herbivory is needed to better manage natural environments. We investigated the effects of post-fire herbivory on understory plant communities in a coastal eucalypt forest in southeastern Australia. We quantified herbivore activity, understory plant diversity, and dominant plant morphology following a wildfire in 2017 using two sizes of exclosures. Statistical analysis incorporated the effect of exclusion treatments, time since fire, and the effect of a previous prescribed burn. Exclusion treatments altered herbivore activity, but time since fire did not. Herbivory reduced plant species richness, diversity, and evenness and promoted the dominance of the most abundant plants within the understory. Increasing time since fire reduced community diversity and evenness and influenced morphological changes to the dominant understory plant species, increasing size and dead material while decreasing abundance. We found the legacy effects of a previous prescribed burn had no effect on herbivores or vegetation within our study. Foraging by large herbivores resulted in a depauperate vegetation community. As post-fire herbivory can alter vegetation communities, we postulate that management burning practices may exacerbate herbivore impacts. Future fire management strategies to minimize herbivore-mediated alterations to understory vegetation could include aggregating management burns into larger fire sizes or linking fire management with herbivore management. Restricting herbivore access following fire (planned or otherwise) can encourage a more diverse and species-rich understory plant community. Future research should aim to determine how vegetation change from post-fire herbivory contributes to future fire risk.

8.
Sci China Life Sci ; 65(4): 830-837, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34387837

RESUMO

Plant diversity can be affected by both herbivore grazing and soil resources. However, it is unclear if the joint effects of herbivores and soil resources might vary with components of plant diversity. Here, we evaluated the relative and combined effects of herbivore assemblage and soil nitrogen (N) quantity and heterogeneity on the α and ß components of plant diversity in a grassland that was subjected to four years of grazing under differing herbivore assemblages (no grazing, cattle grazing, sheep grazing, and mixed grazing). We found that herbivore assemblage combined with soil N quantity explained 41% of the variation in plant α-diversity, while herbivore assemblage combined with soil N heterogeneity explained 15% of the variation in plant ß-diversity. The independent effects of herbivore assemblage explained more than those of soil N for both α- and ß-diversity (α-diversity: 12% vs. 4%; ß-diversity: 18% vs. 16%). We concluded that the effects of herbivores are stronger than those of soil N, and that grazing-induced changes in soil resources are important drivers of plant diversity change, especially α-diversity. Therefore, we suggest that managing herbivore species by accounting for the effects that their grazing can have on soil resources may be significant for plant diversity maintenance.


Assuntos
Herbivoria , Solo , Animais , Bovinos , Ecossistema , Nitrogênio , Plantas , Ovinos
9.
Braz. j. biol ; 82: e243250, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278502

RESUMO

The Punjab urial (Ovis vignei punjabiensis) is a globally threatened wild sheep species. In Pakistan the species is legally protected and bred in captivity to release into natural habitats to reinforce wild populations. Vigilance and feeding are critical to survival, though the degree to which captive-bred animals exhibit these behaviours post-release has rarely been investigated. We monitored the daily behaviours of five adult urial after release and classifying behaviours from 0600 hrs to 1800 hrs, replicating each one-hour period twice and recording four observations of each animal per hour. At the herd level, vigilance and feeding behaviours were exhibited equally. Males and females invested equal time in feeding, males were more vigilant (p = 0.001) and more aggressive (p = 0.010), and females were more restful (p = 0.019) or engaged in grooming (p = 0.044) or locomotion (p = 0.002). Females spent more time feeding than being vigilant (p = 0.002). Males maintained high levels of vigilance throughout the day. Patterns of resting 1300 hrs to 1500 hrs and feeding in early morning and late afternoon were common for both sexes. Behaviours classified as 'other' were exhibited equally between sexes. Our results reveal positive indications of captive-bred urial balancing threat detection and energy acquisition post-release and exhibiting natural behaviours and activity patterns. We encourage assessment of survivorship to evaluate long-term effectiveness of captive breeding and release as a candidate restoration programme.


O Punjab urial (Ovis vignei punjabiensis) é uma espécie de ovelha selvagem ameaçada globalmente. No Paquistão, a espécie é legalmente protegida e criada em cativeiro para ser liberada em habitats para reforçar as populações selvagens. Vigilância e alimentação são essenciais para a sobrevivência, embora o grau de comportamento que os animais criados em cativeiro apresenta raramente tenha sido estudado. Cinco uriais adultos foram monitorados diariamente, após a liberação os comportamentos foram classificados das 6 h às 18 h, replicando cada período de uma hora por duas vezes e registrando quatro observações de cada animal por hora. Em nível do rebanho, os comportamentos de vigilância e alimentação foram exibidos igualmente. Machos e fêmeas investiam tempo igual na alimentação, enquanto os machos eram mais vigilantes (p = 0,001) e mais agressivos (p = 0,010), as fêmeas eram mais repousantes (p = 0,019) ou mais engajadas no asseio (p = 0,044) ou na locomoção (p = 0,002). As fêmeas passam mais tempo se alimentando do que vigiando (p = 0,002). Os machos mantiveram altos níveis de vigilância ao longo do dia. Padrões de descanso de 1300 a 1500 horas e alimentação no início da manhã e no final da tarde eram comuns para ambos os sexos. Comportamentos classificados como "outros" foram exibidos igualmente entre os sexos. Os resultados revelam indicações positivas na detecção de ameaça em relação ao equilíbrio de criação urial em cativeiro e em aquisição de energia pósliberação, exibindo comportamentos naturais e padrões de atividade. Neste estudo, encorajou-se a utilização da avaliação de sobrevivência para avaliar a eficácia em longo prazo da reprodução em cativeiro e soltura como um programa de restauração dos candidatos.


Assuntos
Animais , Masculino , Feminino , Ecossistema , Carneiro Doméstico , Paquistão , Ovinos
10.
Braz. j. biol ; 82: 1-7, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468531

RESUMO

The Punjab urial (Ovis vignei punjabiensis) is a globally threatened wild sheep species. In Pakistan the species is legally protected and bred in captivity to release into natural habitats to reinforce wild populations. Vigilance and feeding are critical to survival, though the degree to which captive-bred animals exhibit these behaviours post-release has rarely been investigated. We monitored the daily behaviours of five adult urial after release and classifying behaviours from 0600 hrs to 1800 hrs, replicating each one-hour period twice and recording four observations of each animal per hour. At the herd level, vigilance and feeding behaviours were exhibited equally. Males and females invested equal time in feeding, males were more vigilant (p = 0.001) and more aggressive (p = 0.010), and females were more restful (p = 0.019) or engaged in grooming (p = 0.044) or locomotion (p = 0.002). Females spent more time feeding than being vigilant (p = 0.002). Males maintained high levels of vigilance throughout the day. Patterns of resting 1300 hrs to 1500 hrs and feeding in early morning and late afternoon were common for both sexes. Behaviours classified as 'other' were exhibited equally between sexes. Our results reveal positive indications of captive-bred urial balancing threat detection and energy acquisition post-release and exhibiting natural behaviours and activity patterns. We encourage assessment of survivorship to evaluate long-term effectiveness of captive breeding and release as a candidate restoration programme.


O Punjab urial (Ovis vignei punjabiensis) é uma espécie de ovelha selvagem ameaçada globalmente. No Paquistão, a espécie é legalmente protegida e criada em cativeiro para ser liberada em habitats para reforçar as populações selvagens. Vigilância e alimentação são essenciais para a sobrevivência, embora o grau de comportamento que os animais criados em cativeiro apresenta raramente tenha sido estudado. Cinco uriais adultos foram monitorados diariamente, após a liberação os comportamentos foram classificados das 6 h às 18 h, replicando cada período de uma hora por duas vezes e registrando quatro observações de cada animal por hora. Em nível do rebanho, os comportamentos de vigilância e alimentação foram exibidos igualmente. Machos e fêmeas investiam tempo igual na alimentação, enquanto os machos eram mais vigilantes (p = 0,001) e mais agressivos (p = 0,010), as fêmeas eram mais repousantes (p = 0,019) ou mais engajadas no asseio (p = 0,044) ou na locomoção (p = 0,002). As fêmeas passam mais tempo se alimentando do que vigiando (p = 0,002). Os machos mantiveram altos níveis de vigilância ao longo do dia. Padrões de descanso de 1300 a 1500 horas e alimentação no início da manhã e no final da tarde eram comuns para ambos os sexos. Comportamentos classificados como "outros" foram exibidos igualmente entre os sexos. Os resultados revelam indicações positivas na detecção de ameaça em relação ao equilíbrio de criação urial em cativeiro e em aquisição de energia pós liberação, exibindo comportamentos naturais e padrões de atividade. Neste estudo, encorajou-se a utilização da avaliação de sobrevivência para avaliar a eficácia em longo prazo da reprodução em cativeiro e soltura como um programa de restauração dos candidatos.


Assuntos
Animais , Comportamento Alimentar , Comportamento Animal , Ovinos , Vigilância em Desastres
11.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468718

RESUMO

Abstract The Punjab urial (Ovis vignei punjabiensis) is a globally threatened wild sheep species. In Pakistan the species is legally protected and bred in captivity to release into natural habitats to reinforce wild populations. Vigilance and feeding are critical to survival, though the degree to which captive-bred animals exhibit these behaviours post-release has rarely been investigated. We monitored the daily behaviours of five adult urial after release and classifying behaviours from 0600 hrs to 1800 hrs, replicating each one-hour period twice and recording four observations of each animal per hour. At the herd level, vigilance and feeding behaviours were exhibited equally. Males and females invested equal time in feeding, males were more vigilant (p = 0.001) and more aggressive (p = 0.010), and females were more restful (p = 0.019) or engaged in grooming (p = 0.044) or locomotion (p = 0.002). Females spent more time feeding than being vigilant (p = 0.002). Males maintained high levels of vigilance throughout the day. Patterns of resting 1300 hrs to 1500 hrs and feeding in early morning and late afternoon were common for both sexes. Behaviours classified as other were exhibited equally between sexes. Our results reveal positive indications of captive-bred urial balancing threat detection and energy acquisition post-release and exhibiting natural behaviours and activity patterns. We encourage assessment of survivorship to evaluate long-term effectiveness of captive breeding and release as a candidate restoration programme.


Resumo O Punjab urial (Ovis vignei punjabiensis) é uma espécie de ovelha selvagem ameaçada globalmente. No Paquistão, a espécie é legalmente protegida e criada em cativeiro para ser liberada em habitats para reforçar as populações selvagens. Vigilância e alimentação são essenciais para a sobrevivência, embora o grau de comportamento que os animais criados em cativeiro apresenta raramente tenha sido estudado. Cinco uriais adultos foram monitorados diariamente, após a liberação os comportamentos foram classificados das 6 h às 18 h, replicando cada período de uma hora por duas vezes e registrando quatro observações de cada animal por hora. Em nível do rebanho, os comportamentos de vigilância e alimentação foram exibidos igualmente. Machos e fêmeas investiam tempo igual na alimentação, enquanto os machos eram mais vigilantes (p = 0,001) e mais agressivos (p = 0,010), as fêmeas eram mais repousantes (p = 0,019) ou mais engajadas no asseio (p = 0,044) ou na locomoção (p = 0,002). As fêmeas passam mais tempo se alimentando do que vigiando (p = 0,002). Os machos mantiveram altos níveis de vigilância ao longo do dia. Padrões de descanso de 1300 a 1500 horas e alimentação no início da manhã e no final da tarde eram comuns para ambos os sexos. Comportamentos classificados como outros foram exibidos igualmente entre os sexos. Os resultados revelam indicações positivas na detecção de ameaça em relação ao equilíbrio de criação urial em cativeiro e em aquisição de energia pós-liberação, exibindo comportamentos naturais e padrões de atividade. Neste estudo, encorajou-se a utilização da avaliação de sobrevivência para avaliar a eficácia em longo prazo da reprodução em cativeiro e soltura como um programa de restauração dos candidatos.

12.
Animals (Basel) ; 11(9)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34573604

RESUMO

Mountain hares (Lepus timidus) in Scandinavia are classified as Near Threatened in the Norwegian and Swedish Redlists. This is due to a possible population decline witnessed during the last decades in Scandinavia. Competition between large herbivores and mountain hares is one of several hypotheses that has been put forward to explain this decline. In a cafeteria trial we investigate the effects of previous moose (Alces alces) winter browsing on the food selection (i.e., biomass consumed, bites per minute and bitediameter) of downy birch (Betula pubescens) and goat willow (Salix caprea) by captive mountain hares. We find that mountain hares do not differentiate among previous browsing levels of downy birch, but have larger bite diameters of goat willow earlier browsed by moose, compared to non-browsed plants. Thus, effects of moose on mountain hare winter food quality seem to be limited. We highlight the need for studies focusing on (1) qualitative effects of moose browsing using wild mountain hares in a natural experimental design, and (2) quantitative effects of moose browsing on available mountain hare forage at a landscape scale during winter.

13.
Glob Chang Biol ; 27(19): 4546-4563, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33993595

RESUMO

Annual variation in phenology can have profound effects on the behavior of animals. As climate change advances spring phenology in ecosystems around the globe, it is becoming increasingly important to understand how animals respond to variation in the timing of seasonal events and how their responses may shift in the future. We investigated the influence of spring phenology on the behavior of migratory, barren-ground caribou (Rangifer tarandus), a species that has evolved to cope with short Arctic summers. Specifically, we examined the effect of spring snow melt and vegetation growth on the current and potential future space-use patterns of the Porcupine Caribou Herd (PCH), which exhibits large, inter-annual shifts in their calving and post-calving distributions across the U.S.-Canadian border. We quantified PCH selection for snow melt and vegetation phenology using machine learning models, determined how selection resulted in annual shifts in space-use, and then projected future distributions based on climate-driven phenology models. Caribou exhibited strong, scale-dependent selection for both snow melt and vegetation growth. During the calving season, caribou selected areas at finer scales where the snow had melted and vegetation was greening, but within broader landscapes that were still brown or snow covered. During the post-calving season, they selected vegetation with intermediate biomass expected to have high forage quality. Annual variation in spring phenology predicted major shifts in PCH space-use. In years with early spring phenology, PCH predominately used habitat in Alaska, while in years with late phenology, they spent more time in Yukon. Future climate conditions were projected to advance spring phenology, shifting PCH calving and post-calving distributions further west into Alaska. Our results demonstrate that caribou selection for habitat in specific phenological stages drive dramatic shifts in annual space-use patterns, and will likely affect future distributions, underscoring the importance of maintaining sufficient suitable habitat to allow for behavioral plasticity.


Assuntos
Ecossistema , Rena , Animais , Canadá , Estações do Ano , Neve
14.
PeerJ ; 9: e10738, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33628635

RESUMO

Ecosystem functioning is dependent a lot on large mammals, which are, however, vulnerable and facing extinction risks due to human impacts mainly. Megafauna of Asia has been declining for a long, not only in numbers but also in their distribution ranges. In the current study, we collected information on past and current occurrence and distribution records of Asia's megafauna species. We reconstructed the historical distribution ranges of the six herbivores and four carnivores for comparison with their present ranges, to quantify spatially explicit levels of mega-defaunation. Results revealed that historically the selected megafauna species were more widely distributed than at current. Severe range contraction was observed for the Asiatic lion, three rhino species, Asian elephant, tigers, and tapirs. Defaunation maps generated have revealed the vanishing of megafauna from parts of the East, Southeast, and Southwest Asia, even some protected Areas losing up to eight out of ten megafaunal species. These defaunation maps can help develop future conservation policies, to save the remaining distribution ranges of large mammals.

15.
Mol Biol Rep ; 48(2): 1995-2003, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33527322

RESUMO

The wild water buffalo (Bubalus arnee) is one of the most endangered and least studied large bovid in the Indian subcontinent. India retains 90% of the estimated global population of >4000 individuals as two fragmented populations in Assam and Chhattisgarh, both threatened by habitat loss and degradation, hunting, disease from livestock, and hybridization with the domestic buffalos. Small, fragmented population size and potential hybridisation pressures from co-occurring domestic buffalos are the major conservation challenges. For the first time, we sequenced the 16,357 bp long mitogenome of three opportunistically collected wild water buffalo samples from Assam (n = 1) and Chhattishgarh (n = 2). The annotated sequence has a base composition of 26.4% T, 26.6% C, 33.1% A and 13.9% G depicting an AT-rich mitogenome composition, including 13 protein-coding genes (11,361 bp), 22 transfer RNA (tRNA) (1514 bp), two ribosomal genes (2525 bp), and a non-coding control region (928 bp). The gene order is conserved with other bovid species. Comparative mitogenome analyses showed both populations are genetically similar but significantly different from domestic buffalo. We also identified structural differences in seven tRNA secondary structures between both species. The genetic distance between wild buffalo and other bovids varied between 0.103 and 0.122. Multiple Bayesian phylogenetic trees showed that both wild and domestic water buffalo formed sister clades which were paraphyletic to other potentially sympatric species of genus Bos. This study provides baseline information on wild buffalo mitogenome for further research on phylogeny, phylogeography and hybrid assessment and help conserving this endangered species.


Assuntos
Búfalos/genética , DNA Mitocondrial/genética , Espécies em Perigo de Extinção , Genoma Mitocondrial , Animais , Teorema de Bayes , Bovinos , Classificação , Genes de RNAr , Variação Genética , Índia , Proteínas Mitocondriais/genética , Filogenia , Filogeografia , Reação em Cadeia da Polimerase , RNA de Transferência/química , RNA de Transferência/genética , Análise de Sequência de DNA
16.
PeerJ ; 9: e10657, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33505805

RESUMO

Grazing by large herbivores is increasingly used as a management tool in European nature reserves. The aim is usually to support an open but heterogeneous habitat and its corresponding plant and animal communities. Previous studies showed that birds may profit from grazing but that the effect varies among bird species. Such studies often compared bird counts among grazed areas with different stocking rates of herbivores. Here, we investigated how space use of Konik horses and Highland cattle is related to bird counts in a recently restored conservation area with a year-round natural grazing management. We equipped five horses and five cattle with GPS collars and correlated the density of their GPS positions on the grazed area with the density of bird observations from winter through the breeding season. We found that in the songbirds of our study site, both the overall density of bird individuals and the number of species increased with increasing density of GPS positions of grazers. Correlations of bird density with horse density were similar to correlations with cattle density. Of the eight most common songbird species observed in our study area, the Eurasian Skylark and the Common Starling had the clearest positive correlations with grazer density, while the Blackbird showed a negative correlation. Skylarks and Starlings in our study area thus seem to profit from year-round natural grazing by a mixed group of horses and cattle.

17.
Glob Chang Biol ; 26(5): 2841-2853, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32069369

RESUMO

Large herbivores, particularly wide-ranging species, are extensively impacted by land use transformation and other anthropogenic barriers to movement. The adaptability of a species is, therefore, crucial to determining whether populations can persist in ever smaller subsets of their historical home ranges. Access to water, by drinking or from forage moisture, is an essential requirement, and surface water provision is thus a long-established, although controversial, conservation practice. In the arid Kgalagadi Transfrontier Park (KTP), South Africa, surface water provision in the 1930s facilitated the establishment of a sedentary wildebeest (Connochaetes taurinus) population in a region historically accessed only in the wet season, via now collapsed long-distance movements. Here, we investigate the behaviour and diet of this wildebeest population, and how these relate to water in the landscape, to better understand the process of transitioning from a mobile to sedentary population. Data from 26 monthly surveys reveal that wildebeest distributions are shaped by water availability and salinity, shade, forage, season and possibly predator detectability. Areas with saline or no water are used predominantly in the wet season when forage moisture is high. Wet season movements beyond the study area mean the timing of wildebeest grazing in these regions matches historical timing. Grass utilization field data suggest that the KTP grazer population experiences forage deficits during the dry season, when ~80% of grass tufts are grazed and C:N and crude protein levels decline. Nonetheless, dung isotope data show that wildebeest meet their crude protein intake requirements during the dry season, likely by consuming unprecedentedly high levels of browse (>33%). While restoring the full historical range and movements of most large herbivore populations is not possible, these findings highlight that understanding the behavioural and dietary adaptability of a species can augment 'next best' efforts to conserve viable populations while home ranges contract.


Assuntos
Antílopes , Animais , Herbivoria , Estações do Ano , África do Sul , Água
18.
J Anim Ecol ; 89(6): 1419-1432, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32108334

RESUMO

Theory predicts that animal populations will be synchronized over large distances by weather and climatic conditions with high spatial synchrony. However, local variation in population responses to weather, and low synchrony in key weather variables or in other ecological processes may reduce the population synchrony. We investigated to what extent temperature and precipitation during different periods of the year synchronized juvenile body mass of moose and reindeer in Norway. We expected high synchronizing effect of weather variables with a high and consistent explanatory power on body mass dynamics across populations, and a weaker synchronizing effect of weather variables whose effect on body mass varied among populations. Juvenile body mass in both species was related to temperature and precipitation during several periods of the year. Temperature had the strongest explanatory power in both species, with a similar effect across all populations. There was higher spatial synchrony in temperature compared to precipitation, and accordingly temperature had the strongest synchronizing effect on juvenile body mass. Moreover, periods with strong explanatory power had stronger synchronizing effect on juvenile body mass in both species. However, weather variables with large variation in the effects on body mass among populations had weak synchronizing effect. The results confirm that weather has a large impact on the spatial structure of population properties but also that spatial heterogeneity, for instance, in environmental change or population density may affect how and to what extent populations are synchronized.


Assuntos
Rena , Tempo (Meteorologia) , Animais , Noruega , Dinâmica Populacional , Estações do Ano , Temperatura
19.
Ann Bot ; 124(7): 1133-1142, 2020 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-31560757

RESUMO

BACKGROUND AND AIMS: Herbivory by large mammals imposes a critical recruitment bottleneck on plants in many systems. Spines defend plants against large herbivores, and how early they emerge in saplings may be one of the strongest predictors of sapling survival in herbivore-rich environments. Yet little effort has been directed at understanding the variability in spine emergence across saplings. METHODS: We present a multispecies study examining whether and how sapling size, spine type and species' environmental niche (light and precipitation environment) influence early emergence and biomass investment in spines. A phylogenetically diverse pool of 45 species possessing different spine types (spines, prickles and thorns; that are derived from distinct plant organs: leaf, epidermis or cortex, and branch, respectively), were grown under common-garden conditions, and patterns of spine emergence and biomass allocation to spines at 5 and 15 weeks after transplanting were characterized. KEY RESULTS: Spine type and species' resource niche were the main factors driving early emergence and investment patterns. Spines emerged earliest in leaf spine-bearing species, and latest in thorn-bearing species. The probability of early spine emergence increased with decreasing precipitation, and was greater in species from open than from closed habitats. Sapling investment in spines changed with plant mass but was contingent on spine type and habitat type. CONCLUSIONS: Different spine types have strikingly different timing of expression, suggesting that developmental origins of spines play a critical role in sapling defences. Furthermore, species from different precipitation and light environments (open vs. closed habitats) showed contrasting patterns of early spine expression, suggesting that resource limitation in their native range may have driven divergent evolution of early defence expression.


Assuntos
Ecossistema , Herbivoria , Animais , Folhas de Planta , Plantas
20.
Ecol Appl ; 30(3): e02053, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31829472

RESUMO

Rangeland ecosystems worldwide are characterized by a high degree of uncertainty in precipitation, both within and across years. Such uncertainty creates challenges for livestock managers seeking to match herbivore numbers with forage availability to prevent vegetation degradation and optimize livestock production. Here, we assess variation in annual large herbivore production (LHP, kg/ha) across multiple herbivore densities over a 78-yr period (1940-2018) in a semiarid rangeland ecosystem (shortgrass steppe of eastern Colorado, USA) that has experienced several phase changes in global-level sea surface temperature (SST) anomalies, as measured by the Pacific Decadal Oscillation (PDO) and the El Niño-Southern Oscillation (ENSO). We examined the influence of prevailing PDO phase, magnitude of late winter (February-April) ENSO, prior growing-season precipitation (prior April to prior September) and precipitation during the six months (prior October to current April) preceding the growing season on LHP. All of these are known prior to the start of the growing season in the shortgrass steppe and could potentially be used by livestock managers to adjust herbivore densities. Annual LHP was greater during warm PDO irrespective of herbivore density, while variance in LHP increased by 69% (moderate density) and 91% (high density) under cold-phase compared to warm-phase PDO. No differences in LHP attributed to PDO phase were observed with low herbivore density. ENSO effects on LHP, specifically La Niña, were more pronounced during cold-phase PDO years. High herbivore density increased LHP at a greater rate than at moderate and low densities with increasing fall and winter precipitation. Differential gain, a weighted measure of LHP under higher relative to lower herbivore densities, was sensitive to prevailing PDO phase, ENSO magnitude, and precipitation amounts from the prior growing season and current fall-winter season. Temporal hierarchical approaches using PDO, ENSO, and local-scale precipitation can enhance decision-making for flexible herbivore densities. Herbivore densities could be increased above recommended levels with lowered risk of negative returns for managers during warm-phase PDO to result in greater LHP and less variability. Conversely, during cold-phase PDO, managers should be cognizant of the additional influences of ENSO and prior fall-winter precipitation, which can help predict when to reduce herbivore densities and minimize risk of forage shortages.


Assuntos
Ecossistema , Herbivoria , Colorado , El Niño Oscilação Sul , Estações do Ano
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