Long‐term declines in nutritional quality of tropical leaves

Rothman, Jessica M.; Chapman, Colin A.; Struhsaker, Thomas T.; Raubenheimer, David; Twinomugisha, Dennis; Waterman, Peter G.

doi:10.1890/14-0391.1

Cited by 60 publications

(43 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…First, foods are complex mixtures of many nutrients parcelled at differing ratios, and each nutrient has its 75 Page 2 of 14 own functional implications for the forager . In addition, the nutritional composition of foods varies geographically (Tait et al 2014;Rothman et al 2015). Second, within populations optimal nutrient intake can be variable, for example where nutrient requirements are sex-or age specific Senior et al 2015).…”

Section: Introductionmentioning

confidence: 99%

Sex-specific macronutrient foraging strategies in a highly successful marine predator: the Australasian gannet

et al. 2016

Self Cite

View full text Add to dashboard Cite

Farewell Spit gannetry in New Zealand. Our results showed intra-and inter-specific variation in the protein, lipid and water composition of prey captured by our sample of 111 Australasian gannets. In addition, we observed significant differences in the Australasian gannets' nutritional niche between seasons. We provide evidence of sex-specific macronutrient foraging strategies in a successful marine predator in the wild. We have shown that in spite of fluctuations in the nutritional composition of foods available to Australasian gannets, males consistently capture prey with higher protein-to-lipid ratios and lower lipid-to-water ratios than females. These results aid to better understand the evolutionary relationship between macronutrient selection and sex-specific traits in wild animals. They also suggest an incentive for these predators to combine individually imbalanced but nutritionally complementary foods to achieve dietary balance, further highlighting the likelihood that prey selection is guided by the balance of macronutrients, rather than energy alone.

show abstract

Section: Introductionmentioning

confidence: 99%

Sex-specific macronutrient foraging strategies in a highly successful marine predator: the Australasian gannet

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…If similar declines have occurred at Ngogo, they could have contributed to the red colobus population decline despite the absence of major changes in stem density for these and other important food species (Lwanga et al 2000;Teelen 2008). However, Rothman et al (2015) also noted that the red colobus population in the Kanyawara study area has apparently remained stable during this time, which makes it unlikely that changed leaf quality alone has accounted for the major population decline at Ngogo. Meanwhile, chimpanzee predation on red colobus has been much less intense at Kanyawara than at Ngogo (Gilby and Wrangham 2007).…”

Section: Discussionmentioning

confidence: 96%

“…Concomitantly, the combined hunting rate for other prey species has increased, as has the likelihood that the chimpanzees hunt their main cercopithecoid prey on encounter, mostly because of an increased likelihood of hunting redtails and mangabeys. Rothman et al (2015) documented declines in leaf quality (lower crude protein and high acid detergent fiber content, hence lower protein-to-fiber ratios) over a 15-to 30-yearr period for several tree species important as red colobus food sources at Kanyawara, another site in Kibale ca. 12 km to the north of Ngogo.…”

Section: Discussionmentioning

confidence: 99%

“…Teelen (2007) found that guereza group density counts varied most among the six species she sampled on her five census transects; this raises the possibility that the change in encounter rates reflects sampling error rather than a real population decline. Alternatively, the population might have declined, but in response to loss of favored habitat as young forest matures (Lwanga 2003) and/or long-term declines in foliage quality (Rothman et al 2015). However, guereza groups are small and the chimpanzees have killed two or more individuals in 46 % of hunts.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Hunting and Prey Switching by Chimpanzees (Pan troglodytes schweinfurthii) at Ngogo

Watts

Mitani

2015

Int J Primatol

View full text Add to dashboard Cite

Predation can have major effects on vertebrate population dynamics, including predator-prey cycles that occur on multiple time scales when predators switch between preferred and alternative prey and changes in the abundance of preferred prey when the availability of alternative prey changes. Predation has been an important selective force in primate social evolution and may regulate some primate populations, but assessing its impact is often difficult. Chimpanzees (Pan troglodytes) provide opportunities for direct collection of data on predation intensity by following habituated predators because they regularly prey on a variety of vertebrates, including other primates. Chimpanzees mostly hunt red colobus monkeys (Procolobus spp.) wherever they live in sympatry. Previous reports have documented heavy predation on red colobus by chimpanzees in the unusually large Ngogo community, in Kibale National Park, Uganda, and have shown an apparent decline in the local red colobus population. Here, we update information on predation at Ngogo, give further evidence of a red colobus population decline, and ask whether the chimpanzees have made more effort to hunt alternative prey in response. Data collected between 1995 and 2014 show that the rate of alternative prey hunts has increased significantly, while the rate of red colobus hunts has declined. Predation on red colobus peaked in 2002; other prey have since accounted for significantly higher proportions of hunts and prey captures. The overall hunting rate has not changed significantly, but per capita meat availability has decreased because hunts of alternative prey lead to fewer captures than hunts of red colobus. The likelihood that the chimpanzees hunt red colobus on encounter has not changed significantly. In contrast, the likelihood of hunting on encounter has increased (redtail monkeys, Cercopithecus ascanius; gray-cheeked mangabeys, Lophocebus albigena) or remained stable (guerezas, Colobus guereza) for other primates that are major alternative prey species. Encounter rates have not changed for redtails and Int J Primatol mangabeys, but the guereza encounter rate has decreased. These results imply that the red colobus population is not recovering and raise the possibility that the chimpanzees are having a negative impact on the guereza population. Chimpanzees are not obligate carnivores, but this may make them prone to cause such impacts because their own populations are probably not limited by those of their prey.

show abstract

“…Finally, we examined the CP/NDF ratio of food items from 70 plant species presented to the monkeys. In several primate studies, the protein‐to‐fiber ratio of leaves has been found to be positively correlated with dietary preference (Matsuda et al, 2017; Rothman et al, 2015; Wasserman & Chapman, 2003). We designated food plant species characterized by leaves with a CP/NDF ratio above the mean value of all tested food items as important candidates for ex‐ and in‐situ forest regeneration programs.…”

Section: Methodsmentioning

confidence: 99%

Cafeteria‐style feeding trials provide new insights into the diet and nutritional strategies of the black snub‐nosed monkey (Rhinopithecus strykeri): Implications for conservation

Yang

Garber

et al. 2020

American J Primatol

View full text Add to dashboard Cite

Anthropogenic changes and fragmentation of natural habitats often exert a negative effect on resource availability and distribution, and the nutritional ecology and feeding behavior of nonhuman primates. The goals of this study are to examine food choice and to identify the nutritional profile of foods consumed by the Critically Endangered black snub‐nosed monkey (Rhinopithecus strykeri). To accomplish our study goals, we presented cafeteria‐style feeding trials of fresh food items collected in the home range of wild black snub‐nosed monkeys to the only two captive R. strykeri, and compared the nutritional profiles of the leafy foods (buds, young, and mature leaves, 100 items from 70 plant species) selected with those avoided (54 items from 48 plant species). Overall, the results indicate that captive R. strykeri selected foods that were higher in moisture (Mo; 77.7%), crude protein (CP; 21.2%), total nonstructural carbohydrates (TNC; 34.9%), and phosphorus (P; 0.37%) while tending to avoid foods with a neutral detergent fiber (NDF) content of greater than 46.8%. Leaves collected in autumn and selected by the monkeys were characterized by a slightly higher amount of metabolizable energy (ME) than those rejected (1,350 kJ/100 g vs. 1,268 kJ/100 g). In contrast, the protein content of foods collected and consumed during the spring was greater (22.9%) than in autumn (16.4%). Random Forests modeling, an ensemble learning method, indicated that the proportion of Mo, NDF, ME, CP, P, and TNC were among the most important factors in predicting which items were consumed by the captive R. strykeri during spring and autumn. On the basis of the nutritional profile of foods consumed across the two seasons, we identified 18 nutrient‐rich native plant species that we recommend for use in ex‐ and in‐situ conservation management and reforestation programs to provide long‐term access to a nutritionally adequate diet.

show abstract

Long‐term declines in nutritional quality of tropical leaves

Cited by 60 publications

References 49 publications

Sex-specific macronutrient foraging strategies in a highly successful marine predator: the Australasian gannet

Sex-specific macronutrient foraging strategies in a highly successful marine predator: the Australasian gannet

Hunting and Prey Switching by Chimpanzees (Pan troglodytes schweinfurthii) at Ngogo

Cafeteria‐style feeding trials provide new insights into the diet and nutritional strategies of the black snub‐nosed monkey (Rhinopithecus strykeri): Implications for conservation

Contact Info

Product

Resources

About