Science

What will 2022 bring?

The end of the year is approaching which makes me think about the science that 2022 will have in store. And maybe you can be a part of it?

Research in the pipeline

I am excited to finish a variety of projects by submitting their preprints and manuscripts next year. Be prepared to see some (more) science on exploration behavior in bats, social foraging in guppies, and aversive conditioning in human-wildlife conflicts. The most rewarding aspect is that all these projects will be followed up, either by me or by the wonderful collaborators I am working with! Keep an eye on these promising young scientists: Theresa Schabacker (Museum fur Naturkunde Berlin, Germany), Gabrielle Lajeunesse (University of Alberta, Canada), and Stefanie White (University of the West Indies, Trinidad & Tobago).

Foraging guppies in the wild

New research

My primary research focus next year will be social foraging in guppies. There are many ideas, too many to execute them myself. So if you are experienced in, or very excited to learn about, applying modeling, video tracking, database queries, and/or machine learning techniques on exciting social foraging data from the wild, please let me know! Of course, our research team is also hoping to make it back to Trinidad next year, so I am keeping my fingers crossed.

I am also very open to new projects about conservation behavior. So if you have a conservation challenge and think that an animal behavior approach would be of added benefit, please contact me!

Trailer recording MOOC
Trailer recording MOOC ‘Introduction to Animal Behaviour’

A new MOOC on Conservation Behavior

2022 will also be the year we design and publish a new Massive Open Online Course (MOOC). This course will be on the relevant topic of Conservation Behavior, related to our 2016 MOOC Introduction to Animal Behaviour. We will discuss conservation challenges related to Human-Induced Rapid Environmental Change (HIREC), Human-Wildlife Conflicts, and Reintroduction or Translocation and highlight when a behavioral perspective can make a difference (and when probably not). For this, I am very excited to work again with the same 2016 team: James Savage and Marc Naguib.

Editor for Animal Behaviour

In January 2022, I will start as an editor for the wonderful ASAB/ABS society journal: Animal Behaviour. I am looking forward to seeing the latest discoveries in animal behavior and to my chance to contribute to the quality of our scientific field! And if you, as ECR, are looking for more reviewing experience, please let me know!

Conservation, Science

New publication: Conditioned taste aversion in human-wildlife conflicts

On the 13th of October, our review on an animal behaviour-based conservation intervention appeared online in Frontiers in Conservation Science. In this review, we visually, quantitatively and narratively synthesize the existing (English) evidence-base on the effectiveness of conditioned taste aversion (CTA) in human-wildlife conflict contexts. By evaluating this literature in the view of learning principles we were able to compose a decision-support table to guide future applications of this technique. Working with all coauthors for the first time, this project has taught me a lot about learning theory and the state-of-the-art application of it in conservation.

Modern wildlife management has dual mandates to reduce human-wildlife conflict (HWC) for burgeoning populations of people while supporting conservation of biodiversity and the ecosystem functions it affords. These opposing goals can sometimes be achieved with non-lethal intervention tools that promote coexistence between people and wildlife.

CTA has been applied to a wide range of animal taxa (57 (sub)species, 26 families and 11 orders)

One such tool is conditioned taste aversion (CTA), the application of an evolutionary relevant learning paradigm in which an animal associates a transitory illness to the taste, odor or other characteristic of a particular food item, resulting in a long-term change in its perception of palatability. Despite extensive support for the power of CTA in laboratory studies, field studies have exhibited mixed results, which erodes manager confidence in using this tool.

Application of CTA in various human-wildlife conflict categories across time

In this paper, we review the literature on CTA in the context of wildlife conservation and management and discuss how success could be increased with more use of learning theory related to CTA, particularly selective association, stimulus salience, stimulus generalization, and extinction of behavior. We apply learning theory to the chronological stages of CTA application in the field and illustrate them by synthesizing and reviewing past applications of CTA in HWC situations. Specifically, we discuss (1) when CTA is suitable, (2) how aversion can be most effectively (and safely) established, (3) how generalization of aversion from treated to untreated food can be stimulated and (4) how extinction of aversion can be avoided.

For each question, we offer specific implementation suggestions and methods for achieving them, which we summarize in a decision-support table that might be used by managers to guide their use of CTA across a range of contexts. Additionally, we highlight promising ideas that may further improve the effectiveness of CTA field applications in the future. With this review, we aspire to demonstrate the diverse past applications of CTA as a non-lethal tool in wildlife management and conservation and facilitate greater application and efficacy in the future.

Reference
Snijders, L., Thierij, N. M., Appleby, R., St Clair, C. C., & Tobajas, J. (2021) Conditioned taste aversion as a tool for mitigating human-wildlife conflicts. Frontiers in Conservation Science, 72: 744704

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.

Communication, Science

New publication: Causal evidence for the adaptive benefits of social foraging in the wild

On 20-01-2021 the latest fruit of our Trinidadian guppy research project came online in the Open Access journal Communications Biology. With this experimental field study, we provide rare causal evidence for the adaptive benefits of social foraging in the wild. For both sexes!

For the complete story, check out the paper here.
For the popular science summary, check below (Dutch version here)

Guppies with friends eat more

Guppies that socialise with more conspecifics get more food. This applies to both males and females, despite the common assumption that males are not very social. This is revealed through a unique field study conducted by Wageningen University & Research in Trinidad in collaboration with Leibniz-Institute of Freshwater Ecology and Inland Fisheries.

‘Much research has already been done under lab conditions on the impact of group size on animals’, says Lysanne Snijders. ‘Still, you never know whether the results such studies show, apply equally in nature’. Moreover, in the wild, other factors such as predators’ presence also influence animals’ social behaviour.

Three female Trinidadian guppies

Benefits of social behaviour

As far as we know, this is the first time a causal relationship was found between the number of animals of the same vertebrate species and it’s benefits to individuals. In Trinidad, Snijders and her colleagues were able to get a close look at the influence of size and composition of groups under natural circumstances by distributing the guppies over different pools. The behaviour of the fish in different group sizes was extensively analysed and recorded.

Snijders and her team showed that guppies living in larger groups were often more successful at obtaining food. From an evolutionary perspective this is interesting: apparently, an increased food intake is a direct benefit of being social in the wild (as is protection from predators), and may thus partly explain why we often see guppies engage in social associations.

Our fieldwork site in the Trinidad rainforest

Males

Moreover, the study, published in Communication Biology, shows that males and females alike benefit from larger groups. This is remarkable, as females are generally perceived as more social.

Snijders: ‘In the vast majority of guppy research, the study is limited to females because males are thought to be predominantly occupied with mating opportunities. This study, under natural circumstances, clearly shows that males also benefit from social behaviour and that this advantage is not solely restricted to them obtaining females. Assumptions about a lower level of sociability do thus not necessarily translate into fewer social benefits.’

Guppies eating a berry they just found

Reference

Snijders, L., Krause, S., Tump, A.N. et al. Causal evidence for the adaptive benefits of social foraging in the wild. Commun Biol 4, 94 (2021). https://doi.org/10.1038/s42003-020-01597-7