Diel Activity Patterns of Three Sympatric Medium-Sized Carnivores during Winter and Spring in a Heavy Snowfall Area in Northeastern Japan

Temporal niche partitioning between carnivores differs depending on the analytical method: comparison between temporal overlap and co-occurrence, and time-to-encounter analyses

“…To assess the reliability of the D statistic and its 95% con dence intervals (CI), we performed a smoothed bootstrap with 10,000 bootstrap samples 25 . To reduce duplicate counts of the same individual, when we collected consecutive detections of the same species at a camera-trap site within 30 min, we treated it as a single sample (e.g., 19,21,28,30,57 ). These analyses were performed using the 'overlap' package 25 in R.…”

“…1b). We only analyzed nighttime because the three target species were nocturnal in this study area 30,57 . We used two methods: the probabilistic co-occurrence analysis 45 that compares the observed data with simulated data generated by combinatorics, and the checkerboard score 44 that compares the observed data with simulated data generated through 1,000 randomizations.…”

“…In the MRPP, the time-to-encounter data between two species may span multiple days 34 . However, our focal species are typically nocturnal 30,57 and the time-to-encounter data may include daytime when they are inactive or at the resting sites. Considering these factors, we performed the MRPP with an upper limit on the time-to-encounter data to focus on a more detailed scale.…”

Seasonal variation in dietary patterns and trophic niche overlap among three sympatric medium-sized carnivores in a cool-temperate zone

“…The study mainly focused on red foxes ( Vulpes vulpes ), Japanese martens ( Martes melampus ), and raccoon dogs ( Nyctereutes procyonoides ), which co-occur in the cool-temperate zone of Japan (Watabe & Saito 2021, 2022, Suzuki & Saito 2023). They are likely to be potentially competitive interactions (Donadio & Buskirk 2006) because of their taxonomy, body size (Ohdachi et al 2015), and dietary similarities (raccoon dog: Sutor et al 2010, red fox: Hisano et al 2021, Japanese marten: Hisano et al 2019, Tsuji et al 2019).…”

“…They are likely to be potentially competitive interactions (Donadio & Buskirk 2006) because of their taxonomy, body size (Ohdachi et al 2015), and dietary similarities (raccoon dog: Sutor et al 2010, red fox: Hisano et al 2021, Japanese marten: Hisano et al 2019, Tsuji et al 2019). Their temporal niche overlap is also relatively high (Watabe & Saito 2021, 2022, Watabe et al 2022). Therefore, it is suitable for evaluating how trophic niche partitioning facilitates carnivore coexistence in the cool-temperate zones of Japan.…”