Males of a feather flock together

Behavioral scientists tested biological principle on free-living Assamese macaques

Date:August 14, 2019

Source:Deutsches Primatenzentrum (DPZ)/German Primate Center

"Birds of a feather flock together" or rather "opposites attract"? The recently published study on male macaques in Thailand speaks for the former: Behavioral biologists from the German Primate Centre -- Leibniz Institute for Primate Research and psychologists from the University of Göttingen have observed that the more similar male Assamese macaques are in their personality, the closer they get and the stronger their social bonds. The scientists were able to rule out the possibility that the causality works the other way round, i.e. that close partners would become more and more similar over time, because the males' personality remained stable even if they migrated between groups and thus changed their social partners. It is suggested that this behavior provides an evolutionary advantage: If the friend has a similar personality, this facilitates communication and coordination and thus cooperation in critical situations (Animal Behaviour).

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Rare antelopes and black cats

Date: August 14, 2019

Source: University of Würzburg

Tanzania is home to a very elusive antelope species that cannot be found anywhere else in the world. According to the Red List, it can be classified as endangered. The first photograph of one of these antelopes was taken by researches as recently as the year 2003. So far, the distribution of this species on Mt. Kilimanjaro has not been documented. Its scientific name: Abbott's duiker (Cephalophus spadix).

However, now there are numerous videos showing this antelope. The film sequences were taken by a research group of Julius-Maximilians-Universität (JMU) Würzburg in Bavaria, Germany. The group has been doing research on biodiversity at Kilimanjaro for years. Current research has focused, among other things, on the question of how the biodiversity of larger mammals is influenced by climate change and human activities.

"We recorded the Abbott's Duiker with our video traps at eleven locations at altitudes between 1920 and 3849 meters for a total of 105 times," says doctoral student Friederike Gebert from the JMU Biocenter. "There's even a video of a mating attempt," says the scientist. And that's not the only special feature that has now been captured on film.

Tens of thousands of video sequences evaluated

The team led by JMU Professor Ingolf Steffan-Dewenter and Dr. Marcell Peters installed a total of five camera traps each on 66 study plots at Kilimanjaro -- from the savannah in the lowlands to the forest regions at medium altitudes to the bush landscape at altitudes of up to 4550 metres. The cameras remained on site for two weeks, after which they were collected and evaluated.

Friederike Gebert had 80,000 film snippets to go through, of which 1,600 were actually showing mammals. Among them were a total of 33 wild mammal species -- in addition to the Abbott's duiker, species like bush pig and porcupine, lesser kudu and yellow baboon were documented. Serval cats were also recorded. These yellow-black patterned predators are about the size of lynxes, but more daintily built. The videos also show a very special kind of serval: an animal whose coat is completely black.

Protected areas are important for biodiversity

The results of the JMU research group will be published in the Journal of Animal Ecology. "All in all, we were able to show that the species richness of large mammals is greatest at mid-elevations of the mountain, i.e. in the forest regions," says Friederike Gebert. The more plant biomass and potential prey there are, the greater the biodiversity.

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Tiny GPS backpacks uncover the secret life of desert bats

Date: August 16, 2019

Source: University of Helsinki

A new study from the University of Helsinki using miniaturized satellite-based tags revealed that during drier periods desert bats must fly further and longer to fulfil their nightly needs. According to researchers this signals their struggle in facing dry periods.

Wildlife tracking has revolutionized the study of animal movement and their behavior. Yet, tracking small, flying animals such as desert bats remained challenging. Now a new generation of miniaturized satellite-based tags is allowing unique insights into the life of these mysterious mammals.

Researchers used 1 g GPS devices to reconstruct the movements of yellow-winged bats, one of two false vampire bats occurring in Africa and one of the few desert bats large enough to carrying this innovative technology. "GPS tags have seen up to now a limited use with insectivorous bats due to weight constraints and low success in data collection -- we achieved great results in tracking such a light species," says Irene Conenna, a PhD candidate at the University of Helsinki and the lead author of the study.

Future under the changing climate?

"Bats are some of the most successful desert mammals. Powered flight allows them to efficiently track scarce resources and their nocturnal lifestyle buffers them from the baking sun. However, they still struggle to find enough resources during the drier periods of the year," says Ricardo Rocha, one of the co-authors of the paper.

The study was conducted in Sibiloi National Park, Northern Kenya, along the shores of Lake Turkana, the world's largest desert lake. Researchers placed GPS loggers in 29 bats, 15 in the rainy season and 14 in the dry and, for one week. Their whereabouts were recorded every 30 to 60 minutes every night. This revealed that during dry periods bats used larger home ranges and had extended activity periods, potentially to compensate for a shortage in food resources.

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African elephants demonstrate movements that vary in response to ecological change

Date: August 20, 2019

Source: Colorado State University

Wild African elephants, known for their intelligence, show markedly different movements and reactions to the same risks and resources. A new study led by Colorado State University and Save the Elephants reveals the magnitude and complexity of this variation in behavior and how it occurs in space and time, and among individual animals.

The findings, published in the September issue of Ecology Letters, indicate how elephants employ a diverse array of strategies that they adjust based on ecological changes. In particular, poaching causes elephants to switch their movements. The study results indicate that landscape conservation efforts should consider the needs of the different tactics elephants display.

The research team used GPS tracking data from more than 150 individual elephants followed over 17 years in the Samburu and Buffalo Springs National Reserve in northern Kenya as part of Save the Elephants' long-term monitoring project. The scientists evaluated individual behavior of elephants to identify how each animal used various food and water resources. They then developed new analytical approaches to understand what drives variations among individual elephant behaviors.

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Poo transplants to help save koalas

AUGUST 21, 2019

Poo transplants are helping expand koala microbiomes, allowing the marsupials to eat a wider range of eucalypts and possibly survive habitat loss.

A study featuring University of Queensland researchers has analysed and altered microbes in koalas' guts, finding that a faecal transplant may influence what species of eucalypt koalas can feed on.

UQ School of Chemistry and Molecular Biosciences Dr. Michaela Blyton was inspired to conduct the research after a devastating drop in the koala population on Cape Otway in Victoria.

"In 2013 the koala population reached very high densities, leading them to defoliate their preferred food tree species, manna gum," Dr. Blyton said.

"This led to 70 per cent mortality due to starvation, which was very distressing.

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