Seed Dispersal(Endozoochory)by Golden Snub-nosed Monkeys(Rhinopithecus Roxellana)in Shennongjia National Park,central China

Colobine monkeys are primarily folivorous as they have specialized digestion and dental traits.They are usually assumed to be seed predators as consume fruits.However,a considerable proportion of colobine diet is composed of fleshy fruits.They appear to be both mild seed predators and potential dispersers.To examine the role of colobine monkeys as endozoochorous seed dispersers,we studied the wild golden snub-nosed monkeys(Rhinopithecus roxellana),collected their feces and investigated whether seeds were still able to germinate after being ingested by them.In order to acquire seed destruction percentage,retention time and their foraging preferences(food color and size),we conducted feeding experiments using the fruits of twelve tree species and artificial fruits on captive individuals of golden snub-nosed monkey at the breeding center in Shennongjia National Park,Hubei Province,central China.Our research showed that:(1)in the field,a total of 1806 seeds(9 species of plant)were found in their feces from July to November in 2018;intact seeds(number=1336;account for 73.98%)were found in all samples;and the two most abundant species were Actinidia arguta(73.0%)and Rosa caudata(15.0%).This study is the first to conduct germination trials on seed defecated by golden snub-nosed monkeys.The germination rates of Rosa caudata seeds(9.0%)ingested by golden snub-nosed monkeys were higher than that of the control seeds(6.0%and 0.0%).And the other plants' seeds did not germinate.(2)In the captive condition,a large proportion of seeds were destructed(mean:70.1±20.9%;range:34.7-100.0%)on passing through the digestive tract of the monkeys.They had a long retention time:the mean retention time(MRT)of twelve kinds of seeds in the gut of the monkeys was approximately 36±3.8 h(range:28.4-41.7 h).(3)Feeding experiments used the artificial fruits(cooked dough)to verify the preference for food color and size of the captive monkey from June to September in 2019.There were no significant differences in preference index about food color,including five colors:red,yellow,black,brown and green.But they prefer the large size among the three kinds of artificial fruits(5 mm,25 mm,45 mm).Our research explored the seed dispersal(endozoochory)by golden snub-nosed monkey and their preference for the fruit color and size,provided an important case study on the role of colobines in endozoochory.Even if the contribution of each golden snub-nosed monkey is low,the total amount of seeds they disperse via their feeding and the number of seedlings that survive could show that they are not the complete seed predator.Our research has significantly increased understanding of the role of golden snub-nosed monkeys as seed dispersal vectors in temperate forests.