Science

New publication: Acoustic exploration is a repeatable behavioral response in migratory bats

On the 14th of April, my first bat paper came online in the journal Scientific Reports. In this paper, led by the talented Theresa Schabacker, we studied how bats explore novel roost-like environments using a newly developed maze-type testing arena. We here show that individuals differ in how they use echolocation to explore, with some bats consistently under-sampling a novel environment while others over sample.

Through exploration animals gain vital information about the availability of resources, the distribution of conspecifics, and the presence of predators. It also helps them to pick up changes in the environment quicker. Studies on how animals explore novel environments are usually conducted by measuring spatial movements. Yet, when exploring, not only where an animal goes is relevant, but also, or even especially, the information it acquires. Birds get new information primarily by using vision, which is challenging to measure. Bats, on the other hand, primarily use echolocation, which we can measure!

Schematic drawing of the maze used during behavioral assay. A) Opaque start tube where bats were placed at the start of each assay B) Barriers closing entrance to maze C) Gates connecting single chambers D) Position of microphone. ©Rebecca Scheibke

We developed a maze-like test arena in which tree-roosting bats could explore small chambers that were connected through ports. This arena is designed so it can easily be brought to the field, in this case the Pape Ornithological Station in Latvia, and so the bats do not need to be transported away from their habitat. Using a night-vision camera and a sensitive microphone we recorded the spatial and acoustic behavior of migratory Nathusius’ pipistrelles (Pipistrellus nathusii) for two minutes after they voluntarily entered the maze (some never entered). We did this twice for over 50 individual bats and discovered that not only the echolocation behavior and the number of chambers they visited was strongly correlated (more chambers meant more echo calls), individuals also consistently differed in how many calls they made per chamber. Some were just more thorough in sampling these new chambers than others. This sampling behavior was also correlated to another seemingly explorative behavior: the number of times they took peeks (but did not enter) other chambers.

Nathusius pipistrelle. Photo credit: Evgeniy Yakhontov, Creative Commons Attribution-Share Alike 3.0 Unported
Nathusius pipistrelle. These little guys are excellent climbers and crawlers, which helps them in finding suitable new roosts, often in trees and bat boxes. Photo credit: Evgeniy Yakhontov, Creative Commons Attribution-Share Alike 3.0 Unported

These bats remind me of how people differ when going through a museum. Some go and look at every painting in a room while others are satisfied with just a few highlights. Bats are not so different as it turns out. Of course, this raises tons of new questions, like: do more thorough exploring bats indeed detect changes in their environment sooner? Does this bring them a fitness-benefit? Or is it actually very costly to echo-locate this much? And does a quickly changing environment select for more thoroughly exploring bats?

Still so much to explore!

Experimental set-up of maze-type arena for testing exploration behavior in tree-roosting bats. Photo credit: Lysanne Snijders

Reference

Schabacker T, Lindecke O, Rizzi S, Marggraf L, Pētersons G, Voigt CC, Snijders L (2021). In situ novel environment assay reveals acoustic exploration as a repeatable behavioral response in migratory bats. Scientific Reports: Online.

Science

New publication: Don’t forget about your friends

Remember those friends you never see anymore after they got hitched? Not in geese!

In our recently published paper, we show that barnacle geese keep hanging out with there favourite early-life social companions also after they pair up. Females show a break during the breeding season but display their social preferences again in the following winter. Males keep their prefered companions throughout the breeding and wintering season and these companionships were predicted by familiarity and genetic relatedness.

We also show that especially males were aggressive during the breeding season towards both males and females and this possibly hampered their female partners to hang out with their own ‘friends’ during breeding but not winter.

In summary, our study reveals the robustness of social preferences formed early in life, carrying over across pair formation, even after extended temporal disruptions. Our findings thus highlight how the early-life social environment can have life-long consequences on individuals’ social life, even in monogamous species.

Reference
RHJM Kurvers, L Prox, DR Farine, C Jongeling, L Snijders (2019)
Animal Behaviour 164: 25-37
Also as a preprint on BioRxiv 

 

Conservation, Science

New publication: Elephant rewilding

Recently, I received the honourable request to comment on an article about the rewilding of captive Asian elephants. It’s not a topic I am very familiar with, so writing this commentary actually became a wonderful learning experience for me.

Several strong commentaries from cultural, ethical and psychological perspectives were already written. Here I tried to also add a relevant ecological & evolutionary perspective, focussing on the behavioural ecology of Asian elephants and their functional role in the ecosystem.

Abstract: Baker & Winkler make a thought-provoking contribution to the discussion of what role captive animals could play in nature conservation and how we could get there through rewilding. There certainly is potential for captive Asian elephants, Elephas maximus, to become targets of conservation efforts, but there are also many questions: (1) How much do (behavioural) traits of captive-origin animals differ from their free conspecifics? (2) What predicts the likelihood and strength of social reintegration of captive animals into free populations? (3) How much of an Asian elephant’s functional role in the environment can captive animals still fulfil and how may this influence the evolutionary dynamics of Asian elephant populations? These questions are challenging, but also an opportunity to gain crucial knowledge and insight into the elephant’s ecological role, as well as our own.

If you are interested in reading the complete commentary (approx. 1000 words) see here.

Reference
Snijders L (2020) Ecological and evolutionary dynamics of elephant rewilding. Animal Sentience 28(6): 1-4.

Conservation, Science

New publication: Effectiveness of animal conditioning interventions

Our systematic map protocol, outlining the background and methods of our approach to map and review the effectiveness of animal conditioning interventions in reducing human-wildlife conflict, is now online.

SysMap_print

This map is part of a special initiative of a team of behavioural ecologists, who all committed to systematically map and/or review a topic in conservation behaviour. Read more about our plans and the protocols of the other team members here.

SysMap_print2

 

Reference
Snijders L, Greggor A.L., Hilderink F., Doran C. (2019) Effectiveness of animal conditioning interventions in reducing human-wildlife conflict: a systematic map protocol. Environmental Evidence 8: 1-10
https://doi.org/10.1186/s13750-019-0153-7

Communication, Conservation, Science

Exploring Conservation Conflicts

“The art and science of asking questions is the source of all knowledge” – Thomas Berger –

Tanja Straka and I like asking questions. Even more so, we like animals, nature and people. Unfortunately, these three do not always mix well and we want to learn why.

Coming from our respective backgrounds in social sciences and animal sciences, we want to learn about the ins and outs of wildlife conservation conflicts by exploring different perspectives. Because we are convinced that understanding the diverse aspects of conservation conflicts could also open our minds to a diversity of (new) ways to address them.

With that in mind, we are keen to explore Conservation Biology and Animal Behaviour (Ethology), Moral Philosophy (Ethics) and the Human Dimensions of Wildlife (Social Sciences) and their perspectives on real-life conservation conflict situations.

In a blog on Medium (and on Twitter), we would like to share the different viewpoints we encounter in our daily lives and work and to invite people to share their perspectives.

Connect to us and let’s explore together!

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