Biology subjects

Snijders, L.

Publications and source records attributed to Snijders, L..

11 recordsLinked to original sources

bioRxiv2026

Sensitive period for song learning outlasts parent-offspring cohesion in wild zebra finches

Communication is central to social behaviour, with vocalisations playing a crucial role in many species. In some species, vocalisations are learned, with songbirds being key to understanding vocal learning. The Australian zebra finch (Taeniopygia castanotis) is the most studied model organism for vocal learning. In captivity, juveniles are typically housed with their father, where males learn their father song and females develop a preference for that song. In nature, however, the social structure of zebra finches is more dynamic across space and time. To identify the natural social conditions during song learning, we followed zebra finch families across their early life in the wild using automated radio-tracking. The distance between juveniles and their parents increased post-fledging and became similar to the distance between juveniles and unrelated adults by the second half of the song learning period. These findings indicate a highly dynamic social environment during the song learning period and suggest that juvenile males could learn from many tutors and that females may develop broader song preferences. Thus, studies based on one-tutor paradigms should be interpreted carefully with respect to functional implications and highlight that future vocal learning studies could better reflect the social conditions under which song develops.

animal behavior and cognition↗

bioRxiv2026

Local nutrient hotspots shape red deer habitat selection in a nutrient-poor landscape

Nutrient availability in many temperate ecosystems is shaped by soil properties and historical land use. Especially in otherwise nutrient-poor landscapes human-induced, local fertilisation can generate fine-scale mosaics of nutrient hotspots. Whether and how large herbivores respond to such heterogeneity remains poorly understood. We tested whether spatial variation in soil-derived nutrient availability structures habitat selection by large herbivores, using full-year GPS tracking data from 7 red deer (Cervus elaphus) in the Veluwe, the Netherlands. We used soil types as a proxy for nutrient availability and assigned nutrient scores based on soil pH, cation exchange capacity and soil structure. We then evaluated habitat selection across multiple components of space use: (i) home range size; (ii) use of relatively nutrient-rich parts within home ranges; (iii) selection among soil types; and (iv) selection of locally enriched former agricultural patches. Red deer used relatively nutrient-rich within their home range more than expected based on availability, including local patches enriched by former agricultural use. However, site selection did not consistently follow nutrient scores among soil types. These results show that nutrient availability does shape habitat selection, but primarily through fine-scale, localised nutrient enrichment rather than broad-scale variation in soil properties. Our findings demonstrate that nutrient-related foraging contributes to habitat selection in a large wild herbivore, while also revealing that this process is scale- and context-dependent. By repeatedly concentrating their foraging in nutrient-rich patches, large herbivores may contribute to nutrient redistribution across the landscape, with the potential to reinforce or modify existing spatial heterogeneity in resource availability and ecosystem functioning.

ecology↗

bioRxiv2025

Communication networks of wild zebra finches (Taeniopygia castanotis)

Communication networks are widespread across species, permitting information flow and facilitating social connections across space and time. In birds, communication networks are well studied in territorial species with long-range songs connecting individuals across space, where unintended listeners extract information from others signalling interactions. Yet, acoustic signals also play important social roles at short range, forming communication networks that connect individuals within larger social units. Wild zebra finches (Taeniopygia castanotis) provide a unique model system to examine such communication networks in a non-territorial species. Zebra finches breed in loose colonies in the Australian arid zone, move around in pairs or small groups, and gather at social hotspots, thus forming dynamic, potentially multi-level, societies. Here, we quantified singing activity and connectivity using the individually distinctive male song recorded at two breeding sub-colonies and three social hotspots over one to three days. We identified 1,835 song bouts from 163 males based on spectrographic similarities and we assessed within and between individual song assignments with a deep learning model (BirdNET). We constructed communication networks based on temporal singing proximity at shared locations: social hotspots and breeding colonies. We reveal higher singing activity at social hotspots than at breeding sites, with almost no dawn song at either site. Singing peaked later, yet at different times of day between breeding sites and social hotspots. Communication networks, with distinct males singing in close temporal proximity, were apparent in both contexts, with larger networks at hotspots. These networks included some individuals that sang together repeatedly at either site, but overall networks were not strongly nested, with only very few males maintaining associations across breeding colonies and hotspots. These networks may facilitate synchronised foraging and breeding as adaptations to a harsh and unpredictable environment. Additionally, our approach offers a novel road map for widening the understanding of communication networks.

animal behavior and cognition↗

bioRxiv2024

Vocalisations indicate behavioural type in Glossophagine bats

Vocalisations play a crucial role in the social systems of many animals, and may inadvertently reveal behavioural characteristics of the sender. Bats, the second largest mammalian order, rely extensively on vocalisations due to their nocturnal lifestyle and complex social systems, making them ideal for studying links between vocalisations and consistent behavioural traits. In this study, we developed a new testing regime to investigate if consistent individual vocalisation differences in nectarivorous bats are associated with specific behavioural types. We exposed 60 wild, male Glossophaga soricina handleyi bats to novel and risky stressors, and assessed their behavioural and vocal responses. Proactive, exploratory, and bold bats were more likely to produce social calls, and among the vocalising bats, more agitated bats produced higher numbers of social calls. We thus show that bat vocalisation behaviour can be indicative of a certain behavioural type, potentially allowing conspecifics to assess personalities from a distance, which in turn could impact subsequent social interactions, group dynamics, and reproductive success. Our results, in combination with previous findings in birds, suggest that advertent or inadvertent long-distance broadcasting of personality may be widespread, thus opening up new exciting questions about the links between vocalisations and sociality.

animal behavior and cognition↗

bioRxiv2022

Migration strategy varies with novel environment response in common noctule bats

Global ecosystems are changing dramatically due to land transformation and climate change. Global change is a particular challenge for migratory animals that rely on multiple stepping stones on their journeys. Migratory animals have a range of strategies to accomplish this, but not all of these strategies may be appropriate for the challenges ahead. Understanding the variation in migratory strategies and their behavioural correlates is therefore critical to understand how vulnerable species will be in the future, especially in endangered and elusive taxa such as bats. Here, we combined isotopic geolocation with an in-situ behavioural assay to investigate whether behavioural responses to a roost-like novel environment correlated with variation in migration strategies (local or distant origin based on isotopic geographic assignments), in the partially migratory bat, Nyctalus noctula. We quantified emergence behaviour, spatial activity, and echolocation call activity. Local bats were more likely to emerge into the novel environment than bats from more distant origins. However, local and distant bats did not differ in spatial activity and acoustic exploration (relative call activity per space unit). Our findings indicate that local bats may more pro-actively cope with novelty, but that acoustic exploration is equally important for local and migratory bats during explorations.

animal behavior and cognition↗

bioRxiv2022

Ephemeral Resource Availability Makes Wild Guppies More Social

Sociality can facilitate the discovery of novel resources, yet it can also entail costs, including increased competition, aggression, sexual harassment and disease transmission. Selection should therefore favour social flexibility as a response to changes in resource conditions, allowing individuals to adjust their social associations optimally. Quantifying these social adjustments and how they allow individuals to benefit in dynamically changing resource environments can provide insight into the adaptive capacity of wild animal populations. We experimentally studied social flexibility in wild guppies (Poecilia reticulata) by examining their fission-fusion dynamics. Using mixed-sex sets of individually marked fish, we manipulated recent foraging experience by presenting them with unpredictable, ephemeral food patches or control patches in the wild. Guppies exposed to ephemeral food patches significantly increased their sociality, doubling the proportion of time spent social compared to controls. This shift was driven by an increase in the probability of starting social contact and a decrease in the probability of ending social contact. Stronger increases in sociality were associated with individuals more often locating ephemeral food patches, mediated by foraging motivation. Importantly, increased sociality was not merely the result of local aggregation, as exposure to ephemeral food patches increased, rather than reduced, spatial activity. And stronger spatial activity did not result in more time spent social. In a second experiment, fish were briefly presented with food patches they could see and smell but not actually consume. Again, fish increased their level of sociality compared to control, indicating that the observed social response was not merely driven by satiation-related changes in activity budgets. Together, our results highlight the adaptive and dynamic nature of fission-fusion social systems and support the view that wild animals adaptively shape their social environment in response to fluctuations in resource variability.

animal behavior and cognition↗

bioRxiv2020

In situ novel environment assay reveals acoustic exploration as a repeatable behavioral response in migratory bats

Integrating information on species-specific sensory perception together with spatial activity provides a high-resolution understanding of how animals explore environments, yet frequently used exploration assays commonly ignore sensory acquisition as a measure for exploration. Echolocation is an active sensing system used by hundreds of mammal species, primarily bats. As echolocation call activity can be reliably quantified, bats present an excellent animal model to investigate intra-specific variation in environmental cue sampling. Here, we developed an in situ roost-like novel environment assay for tree-cave roosting bats. We repeatedly tested 52 individuals of the migratory bat species, Pipistrellus nathusii, across 24 hours, to examine the role of echolocation when crawling through a maze-type arena and test for consistent intra-specific variation in sensory-based exploration. We reveal a strong correlation between echolocation call activity and spatial activity. Moreover, we show that during the exploration of the maze, individuals consistently differed in spatial activity as well as echolocation call activity given their spatial activity, a behavioral response we term acoustic exploration. Acoustic exploration was correlated with other exploratory behaviors, but not with emergence latency. We here present a relevant new measure for exploration behavior and provide evidence for consistent (short-term) intra-specific variation in the level at which wild bats collect information from a novel environment.

animal behavior and cognition↗

bioRxiv2020

Causal evidence for the adaptive benefits of social foraging in the wild

Sociality is a fundamental organizing principle across taxa, thought to come with a suite of adaptive benefits. However, making causal inferences about these adaptive benefits requires experimental manipulation of the social environment, which is rarely feasible in the field. Here we manipulated the number of conspecifics in Trinidadian guppies (Poecilia reticulata) in the wild, and quantified how this affected a key benefit of sociality, social foraging, by investigating several components of foraging success. As adaptive benefits of social foraging may differ between sexes, we studied males and females separately, expecting females, the more social and risk-averse sex, to benefit more from conspecifics than males. Conducting over 1,600 foraging trials, we found that in both sexes, increasing the number of conspecifics led to faster detection of novel food patches and a higher probability of feeding following detection of the patch, resulting in greater individual resource consumption. The slope of the latter relationship differed between the sexes, with males unexpectedly exhibiting a stronger social benefit. Our study provides rare causal evidence for the adaptive benefits of social foraging in the wild, and highlights that sex differences in sociality do not necessarily imply an unequal ability to profit from the presence of others.

animal behavior and cognition↗

bioRxiv2019

Season-specific carry-over of early-life associations in a monogamous bird species

Social relationships can have important fitness consequences. Although there is increasing evidence that social relationships carry over across contexts, few studies have investigated whether relationships formed early in life are carried over to adulthood. For example, juveniles of monogamous species go through a major life-history stage transition--pair formation--during which the pair bond becomes a central unit of the social organization. At present, it remains unclear if pair members retain their early-life relationships after pair formation. We investigated whether same-sex associations formed early in life carry over into adulthood and whether carry-over was dependent on season, in a monogamous species. Moreover, we investigated the role of familiarity, genetic relatedness and aggression on the perseverance of social associations. We studied the social structure before and after pair formation in captive barnacle geese (Branta leucopsis), a highly social, long-lived, monogamous species. We constructed association networks of groups of geese before pair formation, during the subsequent breeding season, and in the following wintering season. Next, we studied how these associations carried over during seasonal changes. We found that early-life associations in females were lost during the breeding season, but resurfaced during the subsequent wintering season. In males, the early-life associations persisted across both seasons. Association persistence was not mediated by genetic relatedness or familiarity. The high level of aggressiveness of males, but not females, in the breeding season suggests that males may have played a key role in shaping both their own social environment and that of their partners. We show that early-life social relationships can be maintained well into later life. Such relationships can be sustained even if they are temporarily disrupted, for example due to reproductive behaviour. Our findings therefore highlight that the early-life social environment can have life-long consequences on individuals social environment.

animal behavior and cognition↗

bioRxiv2018

Females facilitate male patch discovery in a wild fish population

When individuals are more socially responsive to one sex than the other, the benefits they get from foraging socially are likely to depend on the sex composition of the social environment. We tested this hypothesis by performing experimental manipulations of guppy, Poecilia reticulata, sex compositions in the wild. Males found fewer novel food patches in the absence of females than in mixed-sex compositions, while female patch discovery did not differ between compositions. We argue that these results were driven by sex-dependent mechanisms of social association: Markov chain-based fission-fusion modeling revealed that males reduced sociality when females were absent, while less social individuals found fewer patches. Females were similarly social with or without males. Finally, males, but not females, preferred to join females over males at patches. Our findings reveal the relevance of considering how individual and population-level traits interact in shaping the adaptive value of social living in the wild.

animal behavior and cognition↗

bioRxiv2018

Individual- and population-level drivers of consistent foraging success across environments

Individual foraging is under strong natural selection. Yet, whether individuals differ consistently in their foraging success across environments, and which individual and population-level traits might drive such differences, is largely unknown. We addressed this question in a field experiment, conducting over 1,100 foraging trials with nine subpopulations of guppies, Poecilia reticulata, translocating them across environments in the wild. A-priori, we determined the individual social phenotypes. We show that individuals consistently differed in reaching food, but not control, patches across environments. Social individuals reached more food patches than less social ones and males reached more food patches than females. Overall, individuals were, however, more likely to join females at patches than males, which explains why individuals in subpopulations with relatively more females reached, on average, more food patches. Our results provide rare evidence for individual differences in foraging success across environments, driven by individual and population level (sex ratio) traits.

animal behavior and cognition↗