Nine biomes and nine challenges for the conservation genetics of Neotropical species, the case of the vulnerable giant anteater (Myrmecophaga tridactyla)Miranda, Flávia Regina; Fabrício Machado, Arielli; Clozato, Camila Lara; Silva, Sofia Marques
doi: 10.1007/s10531-022-02461-2pmid: N/A
Conservation genetics provides wildlife managers powerful tools to assist conservation planning, being recognized as an important biodiversity component. Nevertheless, communication between wildlife conservation actors is still not effective. Furthermore, wildlife conservation funds are often allocated to conservation actions incompatible with thorough long-term genetic research. In the Neotropics, the political organization of the territory, the complex socio-economic context, and the environmental heterogeneity impose additional challenges to the use of genetics for wildlife conservation. Here we present an assessment of the state-of-the-art on the conservation genetics of the giant anteater, as a study case. We use this species to discuss key wildlife threats and challenges along nine major Neotropical biomes. We review the main scientific research on the species, comprising and analyzing genetic data, and focusing on each biome and its region-specific threats. Our genetic meta-analysis reveals low levels of genetic diversity for the species, signs of population differentiation and dissimilar demographic trends per biome. Large-scale investigations are needed to disclose between hypotheses of panmixia, population structure and local adaptation, and to better assess the species demography. The limited information available for a known Vulnerable species perfectly illustrates the need for greater and internationally concerted investment in genetic/genomic research in the Neotropics. Finally, we describe the main wildlife conservation challenges per biome assessed, and present open research questions to which genetics could be of paramount importance.
Variable effects of forest diversity on invasions by non-native insects and pathogensWard, Samuel F.; Liebhold, Andrew M.; Fei, Songlin
doi: 10.1007/s10531-022-02443-4pmid: N/A
The geographical distributions of non-native forest insects and pathogens (pests) result from a multitude of interacting abiotic and biotic factors. Following arrival, the presence of suitable host trees and environmental conditions are required for pests to establish and spread, but the role of forest biodiversity in this process is not well-understood. We analyzed county-level data for 22 non-native forest pests in the conterminous United States, developing species-specific models to investigate the effects of spatial contagion, human activities, and host and non-host tree biomass or richness on the occurrence of pest species. Species-specific models indicated that (i) the spatial contagion of invasions was the most common driver of invasion incidence, (ii) facilitation effects from host biomass and richness were present in approximately half of the invasions and almost entirely observed in invasions by sap-feeding insects or pathogens, and (iii) there was substantial variation in the direction and magnitude of the effects of non-host tree biomass and richness on invasion. Our analyses highlighted the prominent role of spatially derived propagule pressure in driving intracontinental invasions whereas effects of forest biodiversity were variable and precluded broad generalizations about facilitation and dilution effects as drivers of forest pest invasions at large spatial scales.
Human presence drives bobcat interactions among the U.S. carnivore guildHubbard, Tru; Cove, Michael V.; Green, Austin M.; Iannarilli, Fabiola; Allen, Maximilian L.; LaRose, Summer H.; Nagy, Chris; Compton, Justin A.; Lafferty, Diana J.R.
doi: 10.1007/s10531-022-02445-2pmid: N/A
Mammalian carnivores are elusive and enigmatic species that often play keystone roles in ecosystems through direct and indirect effects. Growing evidence shows that human activity can impact carnivore behavior and community structure by altering predator-prey interactions, shifting diel activity patterns, and altering wildlife movement. Our goal was to investigate the ecological role of bobcats (Lynx rufus) across carnivore communities in the continental USA by quantifying variation in spatiotemporal patterns and determining what environmental and human factors influenced carnivore community interactions. Using camera trap data from the inaugural nationwide Snapshot USA project dataset collected from September – October 2019, we constructed diel activity density curves, applied multispecies occupancy models, and calculated attraction-avoidance ratios. Our results suggest that bobcats display the greatest flexibility in their diel activity among the suite of carnivores sampled. Further, bobcats respond differentially at large spatial scales relative to the presence of dominant or subordinate carnivores, with fluctuating impacts mediated by human and environmental factors. Bobcats’ co-occurrence with dominant carnivores (i.e., wolves Canis sp., pumas Puma concolor) was influenced primarily by human-related factors, whereas co-occurrence with subordinate carnivores (i.e., foxes) was more influenced by environmental factors (i.e., precipitation, gross primary production [GPP]). Bobcats appear to interpret humans as the apex predator on the landscape regardless of the presence of dominant or subordinate species. Understanding the influence of humans as “super predators’’, as well as the importance of environmental factors that impact intraguild carnivore interactions across the USA is critical for establishing successful management practices to promote functioning communities.
Niche shift in invasive species: is it a case of “home away from home” or finding a “new home”?N.A., Aravind; Shaanker, Maanya Uma; Bhat H. N., Poorna; Charles, Bipin; Shaanker R., Uma; Shah, Manzoor A.; G, Ravikanth
doi: 10.1007/s10531-022-02447-0pmid: N/A
In recent years, there has been a rather acrimonious debate on matters concerning the biology of invasive species, some as fundamental as the definition and what constitutes an invasive species. However, an abiding commonality of all invasive species is the fact that they have all moved away from their native ranges to newer and often non-native ranges. In plants, Lantana camara has shifted from its native South American range distribution to most other parts of the world. In animals, the African giant snail has dispersed from Africa to most parts of Asia. What do such niche shifts signify about the nature and quality of the habitats to which the invasive species have moved? In this paper, using the classical niche paradigm, we analyse if niche shifts of thirty-three of the world’s top invasive species constitute just moving from one habitat to another similar habitat somewhere on the earth (home away from home) or that they have moved to totally new habitats (different from their native home). Surprisingly, our results show that for 90% of the world’s top invasive species, movements have been largely restricted to homes away from home, rather than into alien homes. This clearly indicates the potential inertia that species might face in moving out of their fundamental niche. We discuss these results in the context of the overall debate on invasion biology and how niche conservatism may have played a role in dampening the rates of invasion.
Interactive effects of rangeland management and rainfall on dung beetle diversitySimba, Lavhelesani D.; Pryke, James S.; Roets, Francois; Seymour, Colleen L.
doi: 10.1007/s10531-022-02448-zpmid: N/A
Insects perform many ecosystem functions, yet their responses to disturbance can be unpredictable. Changes in climate may interact with land use disturbances, and given that arthropod species diversity, abundance, and traits within assemblages vary with habitat structure and climatic variables, ecological function may be impaired. Here, we assessed how dung beetle species richness, abundance, functional diversity, mean body size and body size inequality (which can signal assemblage stress responses) varied with climatic, management and habitat variables on livestock farms and protected areas across a rainfall gradient (138–381 mm/year) in arid/semi-arid shrubland (Karoo, South Africa, an area for which entomological biodiversity is relatively poorly known), during a prolonged drought. Species richness was similar between farms and protected areas, but abundance was greater in protected areas. Farms tend to be dominated by sheep in this region, and the type of dung and paucity of dung diversity, along with use of anthelmintics may explain this reduced abundance. Species richness and abundance increased with mammalian herbivore stocking rates and rainfall. Most recent rainfall best predicted species richness, but abundance was best explained by the long-term measure of rainfall (Mean Annual Precipitation). Functional diversity showed no patterns with the environmental or management variables we measured. Mean body length and size variation did not differ between protected areas and farms, but the spread of beetle sizes was more even as vegetation cover increased and soil clay content decreased. Future climate projections indicate extreme declines in rainfall in this area, and our results suggest that this would dramatically impact dung beetle communities. Maintaining vegetation cover may help mitigate effects of climate change.
Long-term changes in bryophyte diversity of central European managed forests depending on site environmental featuresCacciatori, Cecilia; Czerepko, Janusz; Lech, Paweł
doi: 10.1007/s10531-022-02449-ypmid: N/A
Cryptogamic diversity is a reliable indicator of the state of forest ecosystems. In this study we analysed the variations in both bryophyte species richness overall and number of hemerophobic bryophyte species in Central European managed forests over a 20-year time span, based on data collected in 132 plots scattered across Poland. We tested differences in species richness among five temporal replicates, as well as among site types grouped based on elevation a.s.l., dominant tree species and stand age. The analyses revealed no significant trend in species richness across years. Meanwhile, species richness significantly increased along with elevation a.s.l., especially in broadleaved forests. No significant difference in species number between spruce and pine dominated stands emerged for mature stands, while there was a strong difference for young stands, with spruce forest hosting a much higher number of species. Species richness exhibited a slight, but not significant, increase over time in broadleaved forests, no significant variations in pine dominated stands and significant fluctuations in spruce dominated stands, yet without a significant trend. Out of the tested drivers, dominant tree species exhibited the strongest impact on species community composition. Number of hemerophobic and strongly hemerophobic species did not undergo significant variations across years either. The lack of bryophyte diversity trends highlighted in this study suggests Central European managed forests are in an equilibrium sate, maintained by the opposing effects of climate changes, on one side and of more sustainable forest management and pollutant deposition decline, from the other.
Small mammal diversity of a poorly known and threatened Amazon region, the Tapajós Area of Endemismdo Prado, Joyce Rodrigues; Rocha, Rita G.; Bissoli-Silva, Heitor; Mendes-Oliveira, Ana Cristina; Pontes, Regeane C. L.; de A Maués, Paula Cristina R.; Costa, Leonora Pires
doi: 10.1007/s10531-022-02450-5pmid: N/A
The Amazon region is a mosaic of distinct areas of endemism (AoE), each with its evolutionary relationships and biotic assemblages. Among them, the Tapajós AoE is one of the least sampled, and it has been identified as one of the regions with the lowest conservation value. Here we provide a checklist of small mammals based on field and molecular-based identification. We report small mammal taxa from the Tapajós River region identified at the species level and three only identified at the genus level (including lineages of the genera Oecomys, Mesomys, and Monodelphis). An intense sampling effort using complementary methods was undertaken during which specimens were sampled at twelve sampling units, six on each riverbank, then combined with molecular identification to help species identification. Most of the taxa occurring in the Tapajós region are widely found in the eastern part of the Amazon Forest, and three species are endemic. Here, we highlight the unique and important mammal assembly of the Tapajós region and its significance with conservation priorities, which had been neglected until now due to a deficit of sampling efforts. We also point out that increasing research efforts to sample small mammals in the Amazon is crucial to understanding this biome’s biodiversity patterns and biogeography.