Gorilla Abundance Estimations within North-East Moukalaba-Doudou National Park, Gabon
Accurate measures of animal population densities are essential to evaluate conservation status and implement action plans to ensure species survival. Gorilla numbers were assessed using the recce survey method within Moukalaba-Doudou National Park (MDNP) in Gabon using fresh nest counts of up to 1 week old. We walked 3,592 km within a 23.01-km2 study site totalling a sampling effort of 297 days. Encounter rate was 0.12 fresh nests per kilometre, and gorilla density estimates generated by home range sizes (by minimal convex polygon) ranged between 1.14 and 1.48 gorillas/km2. Gorillas preferred mixed forest for nesting over ...
Source: Folia Primatologica - January 26, 2021 Category: Physiology Source Type: research
Body Site and Body Orientation Preferences during Social Grooming: A Comparison between Wild and Captive Chimpanzees and Bonobos
This study aimed to explore whether body site and body orientation preferences during social grooming show species-specific differences (bonobos vs. chimpanzees) and environment-specific differences (captivity vs. wild). Results showed that bonobos groomed the head, the front and faced each other more often than chimpanzees, while chimpanzees groomed the back, anogenitals and more frequently in face-to-back positions. Moreover, captive individuals were found to groom facing one another more often than wild ones, whereas wild individuals groomed the back and in face-to-back positions more. While future studies should expand...
Source: Folia Primatologica - January 15, 2021 Category: Physiology Source Type: research
Population Estimates of Hubbard ’s Sportive Lemur ( < b > < i > Lepilemur hubbardorum < /i > < /b > ) at Zombitse-Vohibasia National Park, Madagascar
Estimates of population size are fundamental to setting conservation priorities for threatened primate species. Many taxa in the lemur genusLepilemur remain understudied, and basic population statistics are often dated, incomplete, or absent. Hubbard ’s sportive lemur (Lepilemur hubbardorum) is known only from the Zombitse-Vohibasia National Park region in southwestern Madagascar. It is listed as Endangered by the IUCN owing to its fragmented, declining habitat and limited geographic range. However, this classification has not been confirmed through systematic population estimates. To address this issue, we undertook lin...
Source: Folia Primatologica - January 8, 2021 Category: Physiology Source Type: research
Quantifying Mineral Intake and the Role of Minerals on Food Selection in Angola Black and White Colobus Monkeys ( < b > < i > Colobus angolensis palliatus < /i > < /b > )
We examined the concentration of 9 minerals (Ca, P, Mg, K, Na, Fe, Zn, Cu, and Mn) in foods consumed byColobus angolensis palliatus inhabiting the Diani Forest of Kenya, and test whether individuals preferentially selected leaves in accordance with their mineral concentrations. We also examined the effects of sex, group, and season on daily mineral intake, quantifying both percentage-based and mass-based intakes. We then compared daily mineral intake values to published recommendations. Behavioral data and plant samples were collected from July 2014 to December 2015. We found that individuals preferred leaves with greater ...
Source: Folia Primatologica - December 22, 2020 Category: Physiology Source Type: research
Mantled Howler Monkeys ( < b > < i > Alouatta palliata < /i > < /b > ) in a Costa Rican Forest Fragment Do Not Modify Activity Budgets or Spatial Cohesion in Response to Anthropogenic Edges
Forest fragmentation increases forest edge relative to forest interior, with lower vegetation quality common for primates in edge zones. Because most primates live in human-modified tropical forests within 1 km of their edges, it is critical to understand how primates cope with edge effects. Few studies have investigated how primates inhabiting a fragment alter their behaviour across forest edge and interior zones. Here we investigate how anthropogenic edges affect the activity and spatial cohesion of mantled howler monkeys (Alouatta palliata) at the La Suerte Biological Research Station (LSBRS), a Costa Rican forest fragm...
Source: Folia Primatologica - December 8, 2020 Category: Physiology Source Type: research
Enter the Matrix: Use of Secondary Matrix by Mouse Lemurs
Madagascar is home to many threatened and endemic primate species, yet this island has seen dramatic declines in lemur habitat due to forest loss. This forest loss has resulted in an increasingly fragmented forest landscape, with fragments isolated from each other by grasslands (i.e., matrix). The grassland matrix is not entirely homogeneous containing matrix elements such as isolated trees and shrubs and linear features such as drainage lines. Because most lemurs are predominantly arboreal, they may preferentially use matrix elements to facilitate dispersal between fragments for access to mates or reduce feeding competiti...
Source: Folia Primatologica - December 8, 2020 Category: Physiology Source Type: research
Contents Vol. 91, 2020
Folia Primatol 2020;91:I –IV (Source: Folia Primatologica)
Source: Folia Primatologica - November 27, 2020 Category: Physiology Source Type: research
Sex-Segregated Range Use by Black-and-White Ruffed Lemurs ( < b > < i > Varecia variegata < /i > < /b > ) in Ranomafana National Park, Madagascar
Ranging behavior is one important strategy by which nonhuman primates obtain access to resources critical to their biological maintenance and reproductive success. As most primates live in permanent social groups, their members must balance the benefits of group living with the costs of intragroup competition for resources. However, some taxa live in more spatiotemporally flexible social groups, whose members modify patterns of association and range use as a method to mitigate these costs. Here, we describe the range use of one such taxon, the black-and-white ruffed lemur (Varecia variegata), at an undisturbed primary rain...
Source: Folia Primatologica - November 10, 2020 Category: Physiology Source Type: research
Diet and Activity Budget in < b > < i > Colobus angolensis ruwenzorii < /i > < /b > at Nabugabo, Uganda: Are They Energy Maximizers?
Conclusion: The high-quality diet of this population appears to allow them to utilize an energy maximization strategy. Their reliance on food items that tend to be clumped in space and time likely explains the frequent fission-fusion behaviour that we observe between core units. Our findings demonstrate that the foraging strategies of colobines may be more flexible than was previously thought and illustrate how food availability and distribution can impact primate social organization.Folia Primatol (Source: Folia Primatologica)
Source: Folia Primatologica - October 30, 2020 Category: Physiology Source Type: research
Daily Distance Traveled Is Associated with Greater Brain Size in Primates
This study aimed to test the influence of daily movement on primates ’ brain sizes, controlling for these other behavioral and ecological factors. We used a large comparative dataset of extant primate species and phylogenetic comparative methods. Our results show a significant correlation between daily movement and brain mass, which is not explained by the influenc e of diet, social group size, HR, or body mass. Hence, from an evolutionary timescale, a longer daily movement distance is not a constraining factor for the energetic investment in a larger brain. On the contrary, increased mobility could have contributed to b...
Source: Folia Primatologica - October 27, 2020 Category: Physiology Source Type: research
Shields on Electric Posts Prevent Primate Deaths: A Case Study at Polonnaruwa, Sri Lanka
When monkeys, such as the toque macaques (Macaca sinica) of Sri Lanka, seek food on the ground near human habitation, they may use electrical posts to escape aggression from conspecifics, dogs, or humans. Shields mounted on electrical posts prevented monkeys from reaching the electrical wires, thereby averting their electrocution: the frequency of electrocutions (n = 0) was significantly less (p #x3c; 0.001) in the 12 years after installation of the shields than in the 12 years before (n = 18). Electric shocks were either fatal (n = 14) or caused permanent injury (n = 4) (collectively referred to as electrocutions hereafte...
Source: Folia Primatologica - September 25, 2020 Category: Physiology Source Type: research
Eye Preference for Emotional Stimuli in Sichuan Snub-Nosed Monkeys
This study presents the first evidence of effects of applying both positive and negative stimuli simultaneously on visual laterality in Old World monkeys. Thirteen captive individuals of Sichuan snub-nosed monkeys (Rhinopithecus roxellana) were chosen as focal subjects in the monocular box task. In total, 4 emotional categories (the preferred, the novel, the neutral, and the fearful) of visual stimuli were applied, and eye preference was recorded when individuals looked at each stimulus through an observation hole in the box. We found evidence of visual laterality at the individual level, but not at the group level for eac...
Source: Folia Primatologica - September 16, 2020 Category: Physiology Source Type: research
Interspecific Difference in Seed Dispersal Characteristics between Japanese Macaques ( < b > < i > Macaca fuscata < /i > < /b > ) and Sympatric Japanese Martens ( < b > < i > Martes melampus < /i > < /b > )
We compared the characteristics of seeds within faeces between semi-terrestrial Japanese macaques (Macaca fuscata) and sympatric arboreal Japanese martens (Martes melampus) in Shiga Heights, central Japan. We collected faecal samples of the two mammalian species for 1 year (n = 229 for macaques andn = 22 for martens). We then compared the proportion of seed occurrence, life-form composition, number of seeds and species richness within single faecal samples, and the seed intact ratio between the two mammalian species. We detected seeds from 20 and 7 species from macaque and marten faeces, respectively. Macaque faeces contai...
Source: Folia Primatologica - August 28, 2020 Category: Physiology Source Type: research
Affiliative Contact Calls during Group Travel: Chirp and Wail Vocalization Use in the Male Ring-Tailed Lemur ( < b > < i > Lemur catta < /i > < /b > )
Affiliative vocalizations occur across primate taxa and may be used to maintain spatial cohesion and/or to regulate social interactions in group-living species. For gregarious strepsirhines like the ring-tailed lemur (Lemur catta), with large vocal repertoires and several distinct affiliative vocalizations including the chirp and wail, it is important to understand behavioural usage of these vocalizations to gain insight into their social interactions. To determine whether chirp and wail vocalizations facilitate group cohesion, regulate interactions to achieve socially positive outcomes, and are correlated with differences...
Source: Folia Primatologica - August 5, 2020 Category: Physiology Source Type: research
Prolonged Torpor in Goodman ’s Mouse Lemur ( < b > < i > Microcebus lehilahytsara < /i > < /b > ) from the High-Altitude Forest of Tsinjoarivo, Central-Eastern Madagascar
The nocturnal mouse and dwarf lemurs from Madagascar are known to express heterothermy. Whereas dwarf lemurs (Cheirogaleus) are obligate hibernators, mouse lemurs (Microcebus) can express a great range of heterothermic responses, including daily torpor, prolonged torpor or hibernation, depending on the species, population or individual. Although there is indirect evidence of heterothermy in a handful of mouse lemur species, direct physiological confirmation is currently limited to four:Microcebus berthae(dry forest), M. ravelobensis(dry forest),M. griseorufus(spiny forest), M. murinus(dry forest/littoral forest). We studie...
Source: Folia Primatologica - July 30, 2020 Category: Physiology Source Type: research
