Endozoochorous seed dispersal by Japanese macaques (Macaca fuscata): Effects of temporal variation in ranging and seed characteristics on seed shadows

Abstract

Variation in seed shadows generated by frugivores is caused by daily, seasonal, and inter-annual variation in ranging, as well as inter-specific variability in gut passage times according to seed characteristics. We studied the extent to which seed weight, specific gravity, and daily (morning, afternoon, and evening) and inter-annual (2004 vs. 2005) variation in ranging affected seed shadows generated by wild Japanese macaques (Macaca fuscata) in northern Japan. The macaques ingested fleshy fruits of 11 species during the two year study period; Viburnum dilatatum (Caprifoliaceae: heavier seeds with higher specific gravity) and Rosa multiflora (Rosaceae: lighter seeds with lower specific gravity) were eaten frequently in both years. The travel distances of macaques after feeding on V. dilatatum and R. multiflora fruits were estimated by combining feeding locations and ranging patterns measured in the field with gut passage times of model seeds in captive animals. Median travel distances after fruit feeding were 431 (quantile range: 277-654) and 478 m (265-646), respectively, with a maximum of 1,261 m. Neither year nor time of day affected travel distances. The gut passage time of model V. dilatatum seeds was longer than that of model R. multiflora seed, but this did not affect dispersal distances. Seed shadows for both species over 2 years showed unimodal distribution (peak: 101-500 m) and more than 90%, 20%, and 3% of ingested seeds were estimated to be dispersed >100, >500, and >1000 m, respectively, the longest known distances among macaque species. R. multiflora seeds tended to be dispersed further in 2004 than 2005, but V. dilatatum seeds were not, implying that inter-annual variations in ranging pattern due to the distribution and abundance of nut fruiting could affect dispersal distance.

Neglected seed dispersers: endozoochory by Javan lutungs (Trachypithecus auratus) in Indonesia

“…, Sengupta et al . , Tsuji & Morimoto ), and of other frugivorous animals of similar and smaller size (up to 10 kg body weight), such as frugivorous birds (100–1000 m, Corlett ), gibbons ( Hylobates muelleri × agilis : 220 ± 215 m, McConkey ), and civets (216 m on average, Nakashima & Sukor ).…”

“…We followed Tsuji & Morimoto () to calculate the seed shadow generated by the lutungs: we combined the data on the gut passage times and travel distances between the feeding tree and the potential defecation sites. For the seed passage data, S ti is the proportion of seeds passed in time t (after feeding, h) in a given feeding experiment for lutung i , and…”

“…We evaluated the seed passage time (time between feeding and when the first seeds were defecated) and mean retention time (time between feeding and when half of the ingested seeds were defecated). SEED SHADOW MODELING.-We followed Tsuji & Morimoto (2016) to calculate the seed shadow generated by the lutungs: we combined the data on the gut passage times and travel distances between the feeding tree and the potential defecation sites. For the seed passage data, S ti is the proportion of seeds passed in time t (after feeding, h) in a given feeding experiment for lutung i, and…”

“…We collected the feces opportunistically from multiple locations within each of the primate home ranges. We discriminated between the feces of the two primate species based on previous experience (Tsuji & Morimoto ). We collected 20 fecal samples per month for each species (except for September ( N = 19) and December 2011 ( N = 21) for the long‐tailed macaques), and the total number of fecal samples was 480.…”

Fruit syndromes in Viburnum: correlated evolution of color, nutritional content, and morphology in bird-dispersed fleshy fruits

“…The nutritional content of the fruits of most Viburnum species is unknown, but the few that have been studied have lipid contents ranging from very low (~2% dry weight, e.g., V. opulus) to very high (> 40% dry weight, e.g., V. dentatum) [13,[33][34][35][36][37]. Of the species that have been studied, the vast majority are dispersed by birds although some dispersal by foxes, mustelids, and monkeys has been reported [38][39][40][41][42].…”