Long-term trends in a forest ungulate community: park establishment increases numbers, but poaching is a constant threat

DEAR EDITOR Deforestation represents one of the greatest threats to tropical forest mammals, and the situation is greatly exacerbated by bushmeat hunting. To construct informed conservation plans,information must be gathered about responses to habitat degradation, regeneration, and hunting over a sufficiently long period to allow demographic responses.

A 40-year evaluation of drivers of African rainforest change

Background:Tropical forests are repositories of much of the world’s biodiversity and are critical for mitigation of climate change.Yet,the drivers of forest dynamics are poorly understood.This is in large part due to the lack of long-term data on forest change and changes in drivers.Methodology:We quantify changes in tree abundance,diversity,and stand structure along transects first enumerated in 1978 and resampled 2019 in Kibale National Park,Uganda.We tested five predictions.First,based on the purported role of seed dispersal and herbivory and our quantification of changes in the abundance of frugivores and herbivores,we tested two predictions of how faunal change could have influenced forest composition.Second,based on an evaluation of life history strategies,we tested two predictions concerning how the forest could have changed following disturbance that happened prior to written history.Finally,based on a 50-year climate record,we evaluate the possible influence of climate change on forest dynamics.Results:More trees were present on the assessed transects in 2019(508)than in 1978(436),species richness remained similar,but diversity declined as the number of dominant species increased.Rainfall increased by only 3 mm over the 50 years but this had not significant effect on forest changes measured here.Annual average monthly maximum temperature increased significantly by 1.05℃ over 50 years.The abundance of frugivorous and folivorous primates and elephants increased over the 50 years of monitoring.Neither the prediction that an increase in abundance of seed dispersing frugivores increases the abundance of their preferred fruiting tree species,nor that as an increase in folivore abundance causes a decline in their preferred species were supported.As predicted,light-demanding species decreased in abundance while shade-tolerant species increased as expected from Kibale being disturbed prior to historical records.Finally,while temperature increased over the 50 years,we found no means to predict a priori how individual species would respond.Conclusions:Our study revealed subtle changes in the tree community over 40 years,sizable increases in primate numbers,a substantial increase in the elephant population and an increase in local temperature.Yet,a clear picture of what set of interactions impact the change in the tree community remains elusive.Our data on tree life-history strategies and frugivore/herbivore foraging preferences suggest that trees species are under opposing pressures.

Comparison of gastrointestinal parasite communities in vervet monkeys

Globally,habitat degradation is accelerating,especially in the tropics.Changes to interface habitats can increase environmental overlap among nonhuman primates,people,and domestic animals and change stress levels in wildlife,leading to changes in their risk of parasite infections.However,the direction and consequences of these changes are unclear,since animals may benefit by exploiting human resources(e.g.,improving nutrition­al health by eating nutritious crops)and decreasing susceptibility to infection,or interactions with humans may lead to chronic stress and increased susceptibility to infection.Vervet monkeys are an excellent model to under­stand parasitic disease transmission because of their tolerance to anthropogenic disturbance.Here we quantify the gastrointestinal parasites of a group of vervet monkeys(Chlorocebus aethiops)near Lake Nabugabo,Ugan­da,that frequently overlaps with people in their use of a highly modified environment.We compare the parasites found in this population to seven other sites where vervet monkey gastrointestinal parasites have been identi­fied.The vervets of Lake Nabugabo have the greatest richness of parasites documented to date.We discuss how this may reflect differences in sampling intensity or differences in the types of habitat where vervet parasites have been sampled.