Predation risk increases intraspecific heterogeneity in white-tailed deer diel activity patterns

Abstract Prey species often mitigate predation risk through alteration of spatiotemporal diel activity patterns whereby prey access high-quality resources in risky areas during predator downtimes. However, dominance hierarchies exist in some prey species, and temporal partitioning is a mechanism thought to reduce aggressive intraspecific interactions. How demographic-specific responses to predation risk influence intraspecific temporal partitioning in prey are largely unknown and could be key to understanding the effects of predators on intraspecific interactions in prey. To assess the effects of predation risk on intraspecific interactions in white-tailed deer (Odocoileus virginianus), we monitored deer diel activity during the fawning season in four pairs of predator exclusion and control plots (~40 ha) from 2015 to 2018 using 16 camera traps. We examined the effect of predation risk on diel activity of males, females, and nursery groups by comparing the within-group coefficient of activity overlap (d̂) across predator exclusion and control plots. We then examined within-treatment activity overlap between groups in the predator exclosure and control plots. All groups maintained different diel activity patterns in safe and risky areas. Unconstrained by predation risk, all groups behaved more similarly, and interspecific group overlap was greater in the predator exclusion plots than control plots. Male-nursery group overlap exhibited the strongest treatment effect, increasing 24% in predator exclusion plots (d̂ = 0.91, confidence interval [CI]: 0.87–0.95) relative to control plots (d̂ = 0.67, CI: 0.57–0.76). Our results suggest predators increase heterogeneity in prey behavior and may be important drivers of behavioral processes, such as temporal partitioning, that minimize antagonistic intraspecific interactions of prey.

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Seasonal and diel activity patterns of the endangered taiga bean goose (Anser fabalis fabalis) during the breeding season, monitored with camera traps

PLoS ONE ◽

10.1371/journal.pone.0254254 ◽

2021 ◽

Vol 16 (7) ◽

pp. e0254254

Author(s):

Milaja Nykänen ◽

Hannu Pöysä ◽

Sari Hakkarainen ◽

Tuomas Rajala ◽

Juho Matala ◽

...

Keyword(s):

Breeding Season ◽

Activity Patterns ◽

Time Of Day ◽

Camera Traps ◽

The Arctic ◽

Diel Activity ◽

Ecological Knowledge ◽

Bean Goose ◽

Diel Activity Patterns ◽

Anser Fabalis

Taiga bean goose (Anser fabalis fabalis) is an endangered subspecies that breeds sporadically in remote habitats in the arctic and boreal zones. Due to its elusive behaviour, there is a paucity of knowledge on the behaviour of taiga bean goose during the breeding season, and survey methods for monitoring numbers in the breeding areas are lacking. Camera traps are a useful tool for wildlife monitoring, particularly when there is a need for non-invasive methods due to the shy nature of the species. In this study, we tested the use of camera traps to investigate seasonal and diel activity patterns of taiga bean goose in Finland over two successive breeding seasons, 2018 and 2019. We did this by modelling counts of geese from images with generalized linear and additive mixed models. The camera type (cameras placed by experts specialized in bean goose ecology vs randomly placed cameras) did not influence the count of taiga bean goose (p = 0.386). However, the activity varied significantly by region, Julian day, time of day and temperature, with the study site (individual peatland) and year adding substantial random variation and uncertainty in the counts. Altogether, the best fitting model explained nearly 70% of the variation in taiga bean goose activity. The peak in activity occurred about a month later in the southernmost region compared to the more northern regions, which may indicate behaviours related to migration rather than breeding and moulting. Our results show that long-term monitoring with game camera traps provide a potential unobtrusive approach for studying the behavioural patterns of taiga bean goose and can increase our ecological knowledge of this little-known subspecies. The results can be applied to planning of the annual censuses and finding the optimal time frame for their execution.

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Nonconsumptive Effects of Predation and Impaired Chemosensory Risk Assessment on an Aquatic Prey Species

International Journal of Ecology ◽

10.1155/2015/894579 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 5

Author(s):

Chris K. Elvidge ◽

Grant E. Brown

Keyword(s):

Risk Assessment ◽

Predation Risk ◽

Visual Information ◽

Activity Patterns ◽

Diel Activity ◽

Nonconsumptive Effects ◽

Diel Activity Patterns ◽

Foraging Tactics ◽

Transplant Experiments ◽

Behavioural Strategies

Weak levels of acidity impair chemosensory risk assessment by aquatic species which may result in increased predator mortalities in the absence of compensatory avoidance mechanisms. Using replicate populations of wild juvenile Atlantic salmon (Salmo salar) in neutral and acidic streams, we conducted a series of observational studies and experiments to identify differences in behaviours that may compensate for the loss of chemosensory information on predation risk. Comparing the behavioural strategies of fish between neutral and acidic streams may elucidate the influence of environmental degradation on nonconsumptive effects (NCEs) of predation. Salmon in acidic streams are more active during the day than their counterparts in neutral streams, and are more likely to avoid occupying territories offering fewer physical refugia from predators. Captive cross-population transplant experiments indicate that at equal densities, salmon in acidic streams do not demonstrate relative decreases in growth rate as a result of their different behavioural strategies. Instead, altering diel activity patterns to maximize visual information use and occupying relatively safer territories appear sufficient to offset increased predation risk in acidic streams. Additional strategies such as elevated foraging rates during active periods or adopting riskier foraging tactics are necessary to account for the observed similarities in growth rates.

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Activity patterns of wild Bactrian camels (Camelus bactrianus) in the northern piedmont of the Altun Mountains, China

Animal Biology ◽

10.1163/15707563-00002471 ◽

2015 ◽

Vol 65 (3-4) ◽

pp. 209-217 ◽

Cited By ~ 2

Author(s):

Yadong Xue ◽

Diqiang Li ◽

Wenfa Xiao ◽

Fang Liu ◽

Yuguang Zhang ◽

...

Keyword(s):

Seasonal Variation ◽

Endangered Species ◽

Activity Patterns ◽

Relative Activity ◽

Diel Activity ◽

Arid Areas ◽

Critically Endangered Species ◽

Camelus Bactrianus ◽

Diel Activity Patterns ◽

Bactrian Camels

There are significant gaps in our knowledge of wild camel ecology; especially the activity patterns that allow them to adapt to desert environments. The wild Bactrian camel (Camelus bactrianus) is a critically endangered species that survives in the extreme desert conditions of Central Asia. We conducted camera trapping surveys at seven watering sites in the northern piedmont of the Altun Mountains from 2010 to 2012. We analyzed the frequency of photo-captures to elucidate the wild camels’ diel activity patterns, and the seasonal variation in their activity at watering sites. We found that these wild camels were predominantly diurnal at watering sites, with an increase in relative activity from sunrise, reaching a peak toward midday, and then gradually decreasing in activity until sunset. The camels visited watering sites more often in winter than in summer. These results provide a guide for water development in the conservation of ungulates in arid areas.

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Effects of human settlement and roads on diel activity patterns of elephants (Loxodonta africana )

African Journal of Ecology ◽

10.1111/aje.12552 ◽

2018 ◽

Vol 56 (4) ◽

pp. 872-881 ◽

Cited By ~ 8

Author(s):

Kaitlyn M. Gaynor ◽

Paola S. Branco ◽

Ryan A. Long ◽

Dominique D. Gonçalves ◽

Petter K. Granli ◽

...

Keyword(s):

Activity Patterns ◽

Loxodonta Africana ◽

Diel Activity ◽

Human Settlement ◽

Diel Activity Patterns

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Activity patterns of the small and medium felid (Mammalia: Carnivora: Felidae) guild in northeastern India

Journal of Threatened Taxa ◽

10.11609/jott.4662.11.4.13432-13447 ◽

2019 ◽

Vol 11 (4) ◽

pp. 13432-13447 ◽

Cited By ~ 3

Author(s):

Shomita Mukherjee ◽

Priya Singh ◽

André Pinto Silva ◽

Chandan Ri ◽

Kashmira Kakati ◽

...

Keyword(s):

Activity Patterns ◽

Regional Scale ◽

Diel Activity ◽

Point Scale ◽

Clouded Leopard ◽

Northeastern India ◽

Additional Information ◽

Extant Species ◽

Diel Activity Patterns ◽

Leopard Cat

Fifteen extant species of cats inhabit India, and the northeastern region of the country is among the richest with nine species. Among these are the “standard four”, an assemblage of Clouded Leopard Neofelis nebulosa, Asiatic Golden Cat Catopuma temminckii, Marbled Cat Pardofelis marmorata, and Leopard Cat Prionailurus bengalensis, which also occur across southeastern Asia. Within India, despite several surveys in this region, very little information exists on the ecology of this assemblage to explain their co-occurrence. In this paper, we put together data from several independent camera trapping studies over 10 sites across northeastern India to examine and interpret diel activity patterns of this group. While we present results for all the four species, we focus on two species, the Marbled Cat and Leopard Cat, which are of very similar body size and are potential competitors. We used kernel density estimates to measure diel activity patterns of all four species and overlap in activity between Marbled Cat and Leopard Cat at the regional scale as well as the point scale. We obtained 783 captures of the standard four from >27,500 trap nights. The Asiatic Golden Cat and Marbled Cat were strongly diurnal, Clouded Leopard largely crepuscular and nocturnal, and Leopard Cat largely nocturnal. The degree of overlap between Marbled Cat and Leopard Cat activity was low and in consensus with other studies across southeastern Asia. We interpret this as the differing niche spaces of the two cats due to their specific pre-existing adaptations, not restricted to the effects of competition. The point scale analysis when both cats are captured at the same location and separately show no shift in activity pattern, supporting our hypothesis of pre-existing differences in resources, such as food, playing a major role in facilitating co-existence. Our study, however, is preliminary and additional information with robust analysis is required to test this finding.

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Ontogeny of the diel activity patterns in relation to downstream dispersal in riverine cyprinid fishes

Journal of Fish Biology ◽

10.1111/j.1095-8649.2003.216bk.x ◽

2003 ◽

Vol 63 ◽

pp. 254-254

Author(s):

M. Ondračková ◽

E. Mazurová ◽

M. Reichard ◽

P. Jurajda

Keyword(s):

Activity Patterns ◽

Diel Activity ◽

Diel Activity Patterns ◽

Cyprinid Fishes

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Non-uniform evolutionary response of gecko eye size to changes in diel activity patterns

Biology Letters ◽

10.1098/rsbl.2018.0064 ◽

2018 ◽

Vol 14 (5) ◽

pp. 20180064 ◽

Cited By ~ 10

Author(s):

Lars Schmitz ◽

Timothy E. Higham

Keyword(s):

Phenotypic Diversity ◽

Activity Patterns ◽

Model Fitting ◽

Regime Shifts ◽

Least Square ◽

Diel Activity ◽

Relevant Variable ◽

Eye Size ◽

Evolutionary Response ◽

Diel Activity Patterns

Geckos feature a large range of eye sizes, but what drives this phenotypic diversity is currently unknown. Earlier studies point towards diel activity patterns (DAPs) and locomotory mode, but phylogenetic comparative studies in support of the proposed adaptive mode of eye evolution are lacking. Here, we test the hypothesis of DAPs as the driver of eye size evolution with a dataset on 99 species of gecko. Results from phylogenetic generalized least-square analysis (PGLS) and multivariate model-fitting reveal smaller eyes in diurnal geckos consistent with different phenotypic optima. However, Bayesian analyses of selective regime shifts demonstrate that only two of nine transitions from nocturnal to diurnal activity are coupled with decreases in eye size, and two other regime shifts are not associated with DAP transitions. This non-uniform evolutionary response suggests that eye size is not the only functionally relevant variable. Evolutionary adaptations may therefore include different combinations of several traits (e.g. photoreceptors), all with the same functional outcome. Our results further demonstrate that DAP only partially explains eye size diversity in geckos. As open habitats favour the evolution of large eyes while obstructed habitats favour small eyes, the degree of habitat clutter emerges as another potential axis of eye diversification.

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