Characteristics of buckbrush shrubs exposed to herbivores after seven years of protection

In dense ponderosa pine (Pinus ponderosa Laws.) forests of northern Arizona, forage limitations may lead to severe herbivory by large ungulates on certain plant species. In 1999, we fenced 76 buckbrush (Ceanothus fendleri Gray) shrubs to protect them from herbivores and study growth and reproduction in response to forest restoration treatments implemented on the Fort Valley Experimental Forest. After seven years, we removed fences from around half the plants and examined herbivore impacts on vegetative characteristics. In spring, and again in fall, we measured stem heights and took photographs of exposed shrubs and protected controls. In fall, we also collected stems to analyze size, biomass, and leaf area. Plants exposed to herbivores had significantly less leaf area and total leaf weight than protected control plants. Stem length, diameter, and weight were statistically similar between exposed and control groups. Results from this study suggest that temporary protection from herbivores during the early stages of forest restoration may enhance rates of development and persistence of native plants such as buckbrush

Determinants of reproductive performance among female Gray-cheeked mangabeys (Lophocebus albigena) in Kibale National Park, Uganda

International audienceIdentifying the causes of differential reproductive success is key to understanding natural selection and the forces of selection operating on animals. Here we present results from a 9-yr (2004–2012) study of female reproductive performance in relation to mother’s age and rank, presence of immigrant males, rainfall, and fig fruit abundance in four groups of gray-cheeked mangabeys (Lophocebus albigena) in Kibale National Park, Uganda. We found that females had a rank- and age-specific reproductive pattern, with high-ranking females maturing earlier, having their first births earlier, and exhibiting significantly slower reproductive aging than low-ranking females. We also found that both immigrant and resident males were associated with higher birth rates. Finally, we found that reproduction was aseasonal and did not correlate with rainfall, but that births correlated positively with the abundance of fruits of Ficus spp. Our results show broad similarities between arboreal, forest-dwelling gray-cheeked mangabeys and their more terrestrial, open habitat-dwelling papionin relatives in the importance of dominance rank in estrous cycle initiation, first reproduction, and reproductive aging