Aug 16

A global camera trap network has been used to provide data for the world’s first global camera trap mammal study. Nearly 52,000 images were obtained, documenting 105 different species from 7 protected areas across the Americas, Africa and Asia.

Announced today by an international group of scientists, the results of the study have been published in the article “Community structure and diversity of tropical mammals: data from a global camera trap network“, in the journal Philosophical Transactions of the Royal Society.

Camera trap photo of a Persian leopard at night

Camera trap photo of a Persian leopard at night

First ever global mammal study to use camera traps

Nearly a quarter of all mammal species are threatened, but there is very little information available on global mammal trends. Led by Dr Jorge Ahumada, the team of scientists used camera trap images to look at mammals from protected areas in Brazil, Costa Rica, Indonesia, Laos, Suriname, Tanzania and Uganda.

Between 2008 and 2010, 60 camera traps were set up at each of the 7 locations. One camera trap covered every two square kilometres, and each trap was left for a month.

The photographs the team gathered reveal an amazing variety of animals, including tiny mice, African elephants, gorillas, cougars, giant anteaters and even tourists and poachers.

Photo of a grey-faced elephant-shrew

The grey-faced elephant-shrew was unknown to science until it was captured on film by a camera trap in 2005

‘Protected areas matter’

Analysis of the photographic data has helped the scientists – a team from the Tropical Ecology Assessment and Monitoring (TEAM) Network at Conservation International – to confirm that habitat loss and smaller reserves have a direct and detrimental impact on the diversity and survival of mammal populations.

The scientists found that in general, larger protected areas and continuous areas of forest had a higher diversity of species, a greater variety of animal sizes and more varied diets among the mammals observed.

In contrast, areas with habitat loss and smaller reserves showed a noticeable decline in the diversity of species and less variety in body sizes and diets, with smaller animals and insectivores among the first species to disappear.

Dr Ahumada, lead author of the study, said, “The results of the study are important in that they confirm what we suspected: habitat destruction is slowly but surely killing our planet’s mammal diversity.

We take away two key findings from this research. First, protected areas matter: the bigger the forest they live in, the higher the number and diversity of species, body sizes and diet types. Second, some mammals seem more vulnerable to habitat loss than others: insect-eating mammals — like anteaters, armadillos and some primates, are the first to disappear — while other groups, like herbivores, seem to be less sensitive.

Photo of giant anteater walking

A giant anteater – just one of the species captured by the camera traps in this study

‘Groundbreaking’ scientific methodology

Hailed as a ‘scientifically groundbreaking’ study, using the camera traps means that for the first time there is a way to provide consistent, comparable information for mammals on a global scale. According to Dr Ahumada, by repeating the same methods in the future and comparing the data, scientists will be able to see trends in mammal communities and take specific, targeted action to save them.

Since 2010, the camera trap network has expanded to include a total of 17 sites, with additional cameras now placed in Panama, Ecuador, another site in Brazil, two sites in Peru, Madagascar, Congo, Cameroon, Malaysia and India.

We hope that these data contribute to a better management of protected areas and conservation of mammals worldwide, and a more widespread use of standardized camera trapping studies to monitor these critically important animals,” concluded Dr Ahumada.

Read the full press release at Conservation International and see the camera trap photos taken during the study.

Read the paper in Philosophical Transactions of the Royal Society.

See more camera trap images on ARKive.

Helen Roddis, ARKive Species Text Author