March 19, 2020
How do strangers become
This question was the motivation for our latest study published in Current Biology. My boss and friend Gerry Carter introduced vampire bats from different colonies to each other and observed their social interactions. The unfamiliar bats first seemed to 'test the waters' by investing in low-cost allogrooming, then gradually increased their grooming investment, before they finally formed food-sharing relationships. These findings are consistent with the 'raising the stakes' hypothesis for the formation of cooperative relationships. While Gerry was designing the study and led the fieldwork in Panama, I was running the molecular analyses.
This study is also the prequel of our joint paper on the stability of social bonds. The bats in this more recent study that were captured in Tolé were the same individuals that have been released two years later with proximity sensors.
February 2, 2020
Paper on a non-invasive ECG-sensor
The design of a new non-invasive ECG sensor, which has been developed by my colleague from engineering Niklas Duda, has today been accepted for publication in IEEE Sensors Letters. Hanna Wieser is currently analyzing ECG data from 13 bats species that we collected on a field trip in Panama using this novel sensor node. It does not require implanting of electrodes, they are attached to the depilated skin.
A greater spear-nosed bat (Phyllostomus hastatus) carrying a ECG sensor node with two electrodes attached to the skin. The animal was temporarily kept in a flight cage in Panama.
November 1, 2019
Paper on vampire social bonds
Our first paper on proximity sensing in vampire bats came out on Halloween! Gerry Carter studied the social bonds of a group of females for almost 2 years by quantifying social grooming and food sharing in captivity. We then tagged the bats and released them back into their wild colony inside a hollow tree on a cattle pasture. The high-resolution social networks generated by the proximity sensors showed us that many relationships from captivity survived the dramatic change in the social and physical environ-ment when going from the lab back into the wild.
Selected media responses from around the globe:
A common vampire bat carrying a next-generation proximity sensor. Picture by Sherri & Brock Fenton.
September 12, 2019
NASBR 2019 at Kalamazoo
The annual NASBR meeting is approaching, 23-26 of October! I will be presenting our work on proximity sensing in noctule bats and Gerry Carter will give a talk on social bonds in vampire bats. So lots of opportunities to learn about the latest developments in bat biologging!
August 16, 2019
Paper on fruit chemical ecology
Ectophylla alba is a fig specialists and occurs in Central America
I finally got a paper published on data that I collected on the side during my PhD-fieldwork in Costa Rica. We collected scent of fruits of a typical 'bird-fig' during day and night and compared their bouquets. Turns out that the scent differs significantly between day and night. During biotests we found that Ectophylla alba, a bat that eats these 'bird-figs', is able to find ripe fruit with scent as the only cue. We hypothesize that these changes in scent might be an adaptation of the plant to widen the disperser spectrum (bats & birds).
Read the full paper at PlosONE (open access)
August 16, 2019
Paper on seasonality in bat movements
Today, another study was published, which I co-authored. We show that in Lavia frons, a desert-dwelling bat, homerages and activity levels differ between the dry and the rainy season.
Read the paper at Movement Ecology (open access)