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Unique spatial behavior of the Japanese serow (Capricornis crispus) in the open mountains of Mt. Fuji

Abstract

The Japanese serow (Capricornis crispus) exhibits spatial behavior adapted to forest habitats with relatively stable food supply and climatic conditions, such as sedentary habits, small home ranges, and little seasonal variation in habitat selection. However, investigations have not previously been conducted in open mountainous habitats with high seasonal variability. Therefore, I examined spatial behavior of the Japanese serow in an open mountainous region of Mt. Fuji, central Japan, based on GPS location data. These mountain-dwelling serows had much larger annual home ranges (female: 316.5 ha, male: 373.1 ha) compared with forest-dwelling populations. Spring and summer home range sizes were the largest, and winter home range size was the smallest, ranging from 20.3%–56.1% of maximum. Limited forage and harsh climatic conditions in winter seemed to drive such energy-minimizing behavioral strategies. Selection of vegetation types and elevation varied seasonally, likely because of changes in forage availability and climate conditions. These spatial behaviors in mountain-dwelling serows resemble those of several related mountain ungulates, implying that these behaviors are adaptations to highly seasonal open mountainous habitats. My findings suggest that the main factors affecting spatial behavior are habitat characteristics, such as climate, forage abundance, and seasonality. These findings provide support for an ecological pattern in ungulate spatial behavior whereby closed habitats promote small and stable home ranges, whereas open habitats promote large and seasonally fluctuating home ranges.

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Individual features influence the choice to attack in the southern lapwing Vanellus chilensis, but the opponent type dictates how the interaction goes

Abstract

The fight or flight decision (i.e., engage in or evade from an interaction) is one of the most important for animals, occurring in many different ecological contexts and dictating the occurrence of agonistic encounters that could lead to injuries or even death. The southern lapwing Vanellus chilensis is one of the most conspicuous bird species from South America, living in the natural grasslands but frequently found in rural and urban area. The species is known by its typical vocalization and its patterns of aggression and territoriality, considered exaggerated, creating a cultural prejudice towards the species. To better understand the agonistic interaction process in the species, we used general linear models to verify the influence of individual characteristics, environmental characteristics, and opponent features on five different response variables related to the interactions: the time of alert behavior display, probability to attack and evade, total duration of the interaction, and the Behavioral Diversity Index (BDI) of each interaction. Despite the models showing that for each response variables the predictors had different importance and weights, it was possible to note that individual features like age, breeding status, and month impact directly the probability to evade or attack, while the opponent species and distance better explained the other variables related to the interaction. The results also showed that the southern lapwings increase the intensity of responses and sensibility to intruder during the breeding season, displaying a trade-off between self-preservation and the protection of the offspring that is present in other bird species.

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Epimeletic behavior in a free-ranging female Risso’s dolphin (Grampus griseus)

Abstract

Here, we describe the epimeletic behavior of an adult Risso’s dolphin towards a deceased newborn calf of the same species across several days with photographs, acoustic monitoring, and video recordings. Boat-based observation surveys were conducted from April 2014 to October 2021 along the southern coast of Galicia (northwest Spain) as part of a longitudinal study on the ecology of cetacean species. On September 21, 2020, an adult Risso’s dolphin was observed carrying a dead newborn calf in coastal waters. This presumed mother was further sighted with her deceased calf on September 23 and 24 (20 km and 40 km from the first observation site, respectively) and with other adult individuals on September 30, probably after having lost or finally abandoned the carcass. The presumed mother supported the corpse for at least 5 days, which may have had potential consequences for the female health. As direct observations are scarce in the wild, this type of report provides valuable information to better document the occurrence of care-giving behavior in highly mobile marine top predators.

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Non-aggressive inter-group interactions in wild Northern Gray gibbons (Hylobates funereus)

Abstract

Gibbons exhibit territorial behavior, and mated pairs defend exclusive territories. However, reports on contacts with neighbors near or outside the respective range boundaries are scarce because observing unhabituated neighboring groups is difficult. Studies of encounters have yielded a wide range of observations (aggressive, neutral, communicative, or affiliative) across gibbon species and geographic regions. As it is important to understand behavioral ecology and social relationships among gibbon groups, we studied three Northern Gray gibbon groups (Hylobates funereus) in the Danum Valley Conservation Area (DVCA), Malaysia and observed their interactions with neighboring groups. From 2001 to 2020, three groups were followed for 162 days (2236.4 h), and we observed 30 instances of encounters at the range boundary or intrusions between a study group and a respective neighboring group. Neutral or communicative encounters were observed in most cases, with the exception of one instance of aggressive encounter (chasing). Gibbons interacted through particular vocalizations (termed songs) in many cases. We report details of some characteristic interactions among gibbon groups during encounters at the range boundary or intrusions. Regarding intrusions, we observed an unusual instance where a neighboring group intruded deep into the study group’s territory, and the neighboring group did not respond to the songs of the resident group. Considering that no physical fighting occurred during encounters or intrusions, gibbon groups in the DVCA seem to be non-aggressive toward each other. We briefly discuss possible explanations for such non-aggressive relationships among gibbon groups.

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Underground environment increases the differentiation of personality traits between male and female plateau zokors (Eospalax baileyi)

Abstract

Animal personality is defined as behavior that is consistent across time and context. Ecological and evolutionary pressures might exert sexually dimorphic effects on personality traits. In this study, variations in docility and exploratory behaviors of male and female plateau zokor (Eospalax baileyi) in two populations from different geographical sites were quantified during their breeding season, using bag and open field test. We observed significant repeatability of behaviors in the bag and open field test, except for sniffing behavior in zokors from TZ site. We found that sex influences the personality traits of plateau zokors more than geographical variation in both the bag and open field test. Females had a higher docility than males in the bag test. The findings of this study emphasize the importance of considering plateau zokors’ sex and personality traits when assessing their fitness, behavior, or suitability for behavioral future research work.