Spatial, Temporal, and Dietary Niche Partitioning Among Apex Carnivores and Mesocarnivores in Qilian Mountain National Park, China

Kernekoncepter

Spatial niche partitioning is the key driver facilitating the coexistence of apex carnivore species, while spatial and temporal niche partitioning likely facilitate the coexistence of mesocarnivore species, and spatial and dietary niche partitioning facilitate the coexistence between apex and mesocarnivore species in Qilian Mountain National Park, China.

Resumé

The study explored the spatial, temporal, and dietary niche partitioning among apex carnivores (wolf, snow leopard, Eurasian lynx) and mesocarnivores (Pallas's cat, red fox, Tibetan fox) in Qilian Mountain National Park, China using camera trapping and DNA metabarcoding data.
Key findings:

Apex carnivore species had more overlap temporally or trophically, while mesocarnivore species had high dietary overlap with each other.
Apex carnivore and mesocarnivore species had high temporal overlap.
Spatial niche partitioning is likely the key driver facilitating the coexistence of apex carnivore species.
Spatial and temporal niche partitioning likely facilitate the coexistence of mesocarnivore species.
Spatial and dietary niche partitioning facilitate the coexistence between apex and mesocarnivore species.
Large dietary overlap was observed between wolf and snow leopard, and Pallas's cat and Tibetan fox, suggesting potential for increased resource competition.
Pika, blue sheep and livestock were found to make up a large proportion of carnivore diet.
The findings provide important insights into the mechanisms of niche partitioning among sympatric carnivores and offer helpful information for biodiversity conservation in the region.

Statistik

Occupancy probability of wolf declined with increasing roughness index and increased with prey availability.
Occupancy probability of snow leopard declined with increasing distance to roads and NDVI.
Occupancy probability of red fox increased with higher human disturbance and greater prey availability.
Detection probability of wolf, snow leopard, red fox, and Tibetan fox increased with elevation.

Citater

"Spatial niche partitioning is likely to key driver in facilitating the coexistence of apex carnivore species, while spatial and temporal niche partitioning likely facilitate the coexistence of mesocarnivore species, and spatial and dietary niche partitioning facilitate the coexistence between apex and mesocarnivore species."
"Large dietary overlap was observed between wolf and snow leopard (Pianka's index=0.892) and Pallas's cat and Tibetan fox (Pianka's index=0.997), suggesting the potential for increased resource competition for these species pairs."

Vigtigste indsigter udtrukket fra

Different coexistence patterns between apex carnivores and mesocarnivores based on temporal, spatial, and dietary niche partitioning analysis in Qilian Mountain National Park, China

by Cong,W., Li,... kl. www.biorxiv.org 08-16-2023

https://www.biorxiv.org/content/10.1101/2023.08.14.553226v2

Dybere Forespørgsler

How might climate change and habitat fragmentation impact the niche partitioning and coexistence mechanisms observed in this study?

Climate change and habitat fragmentation can have significant impacts on the niche partitioning and coexistence mechanisms observed in this study.

Climate Change:

Shifts in Habitat: Climate change can lead to shifts in habitat suitability for different species. As temperatures rise, certain habitats may become less suitable for species like the snow leopard or Tibetan fox, forcing them to move to higher elevations where they may encounter new competitors or face challenges in finding suitable prey.
Altered Prey Availability: Changes in climate can also impact the distribution and abundance of prey species, which in turn can affect the dietary preferences and competition among carnivores. For example, if the population of blue sheep, a primary prey for snow leopards, declines due to climate-related factors, it could intensify competition between snow leopards and other predators like wolves.

Habitat Fragmentation:

Reduced Habitat Connectivity: Habitat fragmentation can lead to isolated patches of suitable habitat, making it difficult for species to move between areas. This can disrupt natural movement patterns and lead to increased competition as species are confined to smaller ranges.
Increased Human-Wildlife Conflict: Fragmentation can also bring carnivores into closer contact with human settlements, leading to increased human-wildlife conflict. This can further impact the availability of resources for carnivores and influence their coexistence strategies.

In summary, climate change and habitat fragmentation can disrupt the delicate balance of niche partitioning and coexistence mechanisms among carnivore species by altering habitat suitability, prey availability, and increasing competition and conflict.

What are the potential cascading effects on the broader ecosystem if the resource competition between wolf-snow leopard and Pallas's cat-Tibetan fox intensifies?

If the resource competition between apex carnivores like the wolf and snow leopard, as well as between mesocarnivores like Pallas's cat and Tibetan fox, intensifies, it can have several cascading effects on the broader ecosystem:

Changes in Prey Populations:

Intensified competition for shared prey species can lead to declines in their populations. This can disrupt the trophic cascade within the ecosystem, impacting vegetation dynamics and other species dependent on these prey.

Altered Predator-Prey Dynamics:

Increased competition can alter predator-prey dynamics, potentially leading to fluctuations in predator populations. If one species outcompetes another, it can result in population declines or shifts in distribution patterns.

Impacts on Mesocarnivores:

Mesocarnivores like Pallas's cat and Tibetan fox may face increased pressure from apex predators, affecting their survival and reproductive success. This can have ripple effects on the mesocarnivore population and their interactions with other species in the ecosystem.

Changes in Habitat Use:

Intensified competition may force carnivores to alter their habitat use patterns, potentially leading to habitat degradation or changes in ecosystem structure. This can impact other species sharing the same habitat and disrupt the overall balance of the ecosystem.

Human-Wildlife Conflict:

As competition intensifies, carnivores may encroach more on human settlements in search of resources, leading to increased human-wildlife conflict. This can have negative consequences for both wildlife and human communities in the area.

In essence, intensified resource competition among carnivores can have far-reaching effects on the ecosystem, influencing species interactions, population dynamics, and ecosystem stability.

What other factors, beyond spatial, temporal and dietary dimensions, could influence the coexistence of carnivore species in this region?

In addition to spatial, temporal, and dietary dimensions, several other factors could influence the coexistence of carnivore species in this region:

Reproductive Strategies:

Differences in reproductive strategies, such as breeding seasons, litter sizes, and parental care, can impact the population dynamics and interactions among carnivore species. Species with overlapping reproductive periods may face increased competition for resources.

Communication and Behavior:

Communication methods, social structures, and behavior patterns can influence how carnivores interact and coexist. Dominance hierarchies, territoriality, and communication signals can play a role in reducing conflict and facilitating coexistence.

Human Disturbance:

Human activities, such as habitat destruction, poaching, and disturbance, can disrupt carnivore populations and their coexistence strategies. Increased human presence can lead to habitat loss, fragmentation, and altered behavior in carnivores.

Disease and Parasites:

Disease outbreaks and parasite infestations can impact carnivore populations, affecting their health, reproduction, and behavior. Disease transmission among species can also influence their interactions and coexistence patterns.

Climate Variability:

Beyond long-term climate change, short-term climate variability, such as extreme weather events, can impact carnivore behavior, prey availability, and habitat conditions. Adapting to unpredictable climate patterns can influence coexistence strategies.

Considering these additional factors alongside spatial, temporal, and dietary dimensions can provide a more comprehensive understanding of the complex interactions and mechanisms shaping carnivore coexistence in the region.