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Harten, L.

Publications and source records attributed to Harten, L..

3 recordsLinked to original sources

Seasonal challenges of tropical bats (Rousettus aegyptiacus) in temperate zones

Egyptian fruit bats (Rousettus aegyptiacus) manage to survive and flourish in a large geographic range despite the variability of natural and anthropogenic conditions in this range. To examine the challenges faced by free-ranging R.aegyptiacus living at the northern edge of their distribution, we performed a retrospective analysis of [~]1500 clinical cases reported by a bat rescue NGO over 25 months, from all over Israel. All cases of injured or stranded bats were evaluated and categorized according to date, place, sex, age, and etiology of the morbidity. The analysis of the data showed an increase in all types of morbidity during the wintertime, with more than twice the number of cases in comparison with the summertime, over two consecutive years. Moreover, we found that the number of abandoned pups peaks during spring till autumn when adult morbidity is minimal. We characterize two prominent types of previously undescribed morbidity in R.aegyptiacus, one in the form of bacterial illness, and the other associated with feet deformation which affects bats in addition to major anthropogenic-related threats related to synanthropic predators. We analyze the reasons driving winter morbidity and conclude that winter weather and specifically low temperature best explains this morbidity. We hypothesize that R.aegyptiacus, a fruit-bat of tropical origin is facing major seasonal difficulties near the northern edge of its distribution, probably limiting its further spread northward.

ecology↗

Sick Bats Stay Home Alone: Social distancing during the acute phase response in Egyptian fruit bats (Rousettus aegyptiacus)

Along with its many advantages, social roosting imposes a major risk of pathogen transmission. How social animals, and especially free-ranging mammals, reduce this risk is poorly documented. We used lipopolysaccharide injection to imitate bacterial sickness in both a captive and a free-ranging colony of an extremely social, long lived mammal - the Egyptian fruit bat. We monitored behavioral and physiological responses using an arsenal of methods, including on-board GPS and acceleration, video, temperature and weight measurements, and blood samples. Sick-like bats exhibited an increased immune response, as well as classical illness symptoms including fever, weight loss, anorexia, and lethargy. Notably, they also isolated themselves from the group by leaving the social cluster and avoiding contact. Free-ranging individuals ceased foraging outdoors for at least two nights. Together, these sickness behaviors demonstrate a strong, integrative immune response which promotes recovery of infected individuals while protecting their group members from transmission of pathogens, and at the same time, reducing spillover events outside the roost.

zoology↗

Who is the host of the host-associated microbiome? Colony-level dynamics overshadow individual-level characteristics in the fur microbiome of a social mammal, the Egyptian fruit-bat

In the first longitudinal study of bat microbiomes, we find that unlike the pattern described in humans and other mammals, the prominent dynamics in Egyptian fruit bats fur microbiomes are those of change over time at the level of the colony as a whole. Thus, on average, a pair of fur microbiome samples from different individuals in the same colony collected on the same date are more similar to one another than a pair of samples from the same individual collected at different time points. This pattern suggests that the whole colony may be the appropriate biological unit for understanding some of the roles of the host microbiome in social bats ecology and evolution. This pattern of synchronized colony changes over time is also reflected in the profile of volatile compounds in the bats fur, but differs from the more individualized pattern found in the bats gut microbiome.

ecology↗