Consistent Individual Differences In Behaviour Research Articles

Personality and social foraging tactic use in free-living Eurasian tree sparrows (Passer montanus)

AbstractGroup-foraging individuals often use alternative behavioral tactics to acquire food: some individuals, the producers, actively search for food, whereas others, the scroungers, look for opportunities to exploit the finders’ discoveries. Although the use of social foraging tactics is partly flexible, yet some individuals tend to produce more, whereas others largely prefer to scrounge. This between-individual variation in tactic use closely resembles the phenomenon of animal personality; however, the connection between personality and social foraging tactic use has rarely been investigated in wild animals. Here, we studied this relationship in free-living Eurasian tree sparrows (Passer montanus) during 2 winters. We found that in females, but not in males, social foraging tactic use was predicted by personality: more exploratory (i.e., more active in a novel environment) females scrounged more. Regardless of sex, the probability of scrounging increased with the density of individuals foraging on feeders and the time of feeding within a foraging bout, that is, the later the individual foraged within a foraging bout the higher the probability of scrounging was. Our results demonstrate that consistent individual behavioral differences are linked, in a sex-dependent manner, to group-level processes in the context of social foraging in free-living tree sparrows, suggesting that individual behavioral traits have implications for social evolution.

Personality is associated with dominance in a social feeding context in the great tit

Abstract Despite the growing interest in consistent individual differences in behaviour (animal personality), the influence of social context on different behavioural types remains poorly understood. The suite of correlated behaviours within and across contexts is called behavioural syndromes. Most personality studies have investigated consistent individual behavioural types and their consequences in a asocial context, however few studies have considered the influence of social context on individual behaviour. In addition, the evolutionary and ecological consequences of personality differences in social context remain unknown. In the present study, we confirm individual personality in Great tits (Parus major) using room exploration and neophobia tests. As a result of these two tests, repeatability and correlational structure of two personality traits were investigated. Additionally we assessed the extent to which personality influences dominance in a social feeding context. Great tits remained consistent in their personality traits (exploration and neophobia). Individuals who explored a novel environment faster also approached a novel object faster, while those who spent more time exploring a novel environment were also slower to approach a novel object. In a social feeding context personality was linked to dominance: with proactive individuals being more likely to be dominant. Our result provides evidence of the importance of social context in a wild population of birds and may have fitness consequence, both for focal individuals and their conspecifics.

Personality and artificial light at night in a semi-urban songbird population: No evidence for personality-dependent sampling bias, avoidance or disruptive effects on sleep behaviour

Light pollution or artificial light at night (ALAN) is an increasing, worldwide challenge that affects many aspects of animal behaviour. Interestingly, the response to ALAN varies widely among individuals within a population and variation in personality (consistent individual differences in behaviour) may be an important factor explaining this variation. Consistent individual differences in exploration behaviour in particular may relate to the response to ALAN, as increasing evidence indicates its relation with how individuals respond to novelty and how they cope with anthropogenic modifications of the environment. Here, we assayed exploration behaviour in a novel environment as a proxy for personality variation in great tits (Parus major). We observed individual sleep behaviour over two consecutive nights, with birds sleeping under natural dark conditions the first night and confronted with ALAN inside the nest box on the second night, representing a modified and novel roosting environment. We examined whether roosting decisions when confronted with a camera (novel object), and subsequently with ALAN, were personality-dependent, as this could potentially create sampling bias. Finally, we assessed whether experimentally challenging individuals with ALAN induced personality-dependent changes in sleep behaviour.Slow and fast explorers were equally likely to roost in a nest box when confronted with either a camera or artificial light inside, indicating the absence of personality-dependent sampling bias or avoidance of exposure to ALAN. Moreover, slow and fast explorers were equally disrupted in their sleep behaviour when challenged with ALAN. Whether other behavioural and physiological effects of ALAN are personality-dependent remains to be determined. Moreover, the sensitivity to disturbance of different behavioural types might depend on the behavioural context and the specific type of challenge in question. In our increasingly urbanized world, determining whether the effects of anthropogenic stressors depend on personality type will be of paramount importance as it may affect population dynamics.

Cortisol during adolescence organises personality traits and behavioural syndromes

Despite the growing evidence for the importance of developmental experiences shaping consistent individual differences in behaviour and physiology, the role of endocrine factors underlying the development and maintenance of such differences across multiple traits, remains poorly understood. Here, we investigated how an experimental manipulation of circulating glucocorticoids during early adolescence affects behavioural and physiological variation and covariation later in life in the precocial cavy (Cavia aperea). Plasma cortisol concentrations were experimentally elevated by administering cortisol via food for 3 weeks. Struggle docility, escape latency, boldness, exploration and social behaviour were then tested three times after individuals attained sexual maturity. In addition, blood samples were taken repeatedly to monitor circulating cortisol concentrations. Exogenous cortisol affected mean trait expression of plasma cortisol levels, struggle docility and escape latency. Repeatability of cortisol and escape latency was increased and repeatability of struggle docility tended to be higher (approaching significance) in treated individuals. Increased repeatability was mainly caused by an increase of among-individual variance. Correlations among docility, escape latency and cortisol were stronger in treated animals compared to control animals. These results suggest that exposure to elevated levels of cortisol during adolescence can alter animal personality traits as well as behavioural syndromes. Social and risk-taking traits showed no correlation with cortisol levels and were unaffected by the experimental manipulation, indicating behavioural modularity. Taken together, our data highlight that cortisol can have organising effects during adolescence on the development of personality traits and behavioural syndromes, adding to the increasing evidence that not only early life but also adolescence is an important sensitive period for behavioural development.

Boldness related to size in the hermit crab Coenobita compressus at undisturbed, but not disturbed beach

AbstractThere is growing interest in the consequences of consistent individual behavioral differences within and between populations. We compared the magnitude, repeatability, and plasticity of boldness in the terrestrial hermit crab Coenobita compressus in three habitats with different degrees of disturbance in Costa Rica. We encourage researchers to test additional sites to assess the generality of our results. Boldness decreased with crab size at the less disturbed sites, while no relationship between size and boldness was found at the disturbed site. Boldness increased with habitat disturbance, perhaps because bolder crabs succeed in exploiting food around people. Repeatability and plasticity were similar across sites. We hypothesize that population differences may be the result of developmental plasticity when aquatic larvae settle on a beach or selection for boldness at the disturbed site acting on each new generation.

Who dares does not always win: risk-averse rockpool prawns are better at controlling a limited food resource

Animal ‘personality’, the phenomenon of consistent individual differences in behaviour within populations, has been documented widely, yet its functional significance and the reasons for its persistence remain unclear. One possibility is that among-individual behavioural variation is linked to fitness-determining traits via effects on resource acquisition. In this study, we tested this idea, using rockpool prawns, Palaemon elegans, to test for a correlation between ‘high-risk exploration’ and the ability to monopolize a limited resource. Modified open field trials (OFTs) confirmed that consistent among-individual (co)variation in high-risk exploratory behaviours does exist in this species, and multivariate analysis showed trait variation is consistent with a major axis of personality variation. Subsequent feeding trials in size-matched groups where competition was possible revealed a high repeatability of feeding duration, used here as a proxy for RHP (resource-holding potential). We found significant negative correlations between feeding duration and two ‘risky’ behaviours, such that individuals that took fewer risks fed more. Our results are not consistent with the widely hypothesized idea of a ‘proactive syndrome’ in which bolder, risk-taking personalities are positively associated with RHP. Rather they suggest the possibility of a trade-off, with some individuals successful at monopolizing limited, high-value resources, while others are more willing to engage in potentially risky exploration (which may increase the likelihood of encountering novel resource patches). We speculate that alternative strategies for acquiring limited resources might thereby contribute to the maintenance of personality variation observed in wild populations.

Personality variation in two predator species does not impact prey species survival or plant damage in staged mesocosms

Mounting evidence suggests that consistent individual differences in behavior, better known as animal personality, can shape aspects of population and community ecology. Yet, the potential for animal personality to affect more complex and non-linear food webs, like those seen in nature, remains understudied. Here, we explore the degree to which the aggregate behaviors of two predator species simultaneously interact to alter prey survival rates and the presence and magnitude of trophic cascades. We set up mesocosms in an old-field habitat containing four different insect prey species and either two Phidippus clarus (Salticidae), two Platycryptus undatus (Salticidae), or one of each predator. Prior to initiating each mesocosm, we assayed the activity level and boldness of each individual predator and included these metrics in our models predicting prey survival and plant damage. We then compared the number of surviving prey and plant damage under each of these conditions and tested for associations between each of these response variables and predator behavior. We found no significant effect of predator community composition or predators’ behavior on prey survival or plant damage. These results suggest that the effects of predator personality on prey survival may be subtle or absent in complex species interaction modules. Although much research suggests that animal personality can influence broader scale ecological phenomena, the ability of animal personality to alter complex species interaction modules remains unresolved. We tested whether pairs of predators of different personality types differentially impacted prey survival rates and plant damage in a tritrophic system, and whether these effects varied based on predator community composition. We recovered no evidence that predator personality types influenced prey survival or plant damage regardless of the predator composition considered. These results suggest that the effects of personality may be absent or undetectable in more complex, realistic ecological settings. The majority of laboratory-based personality studies published to date evaluate only dyadic species interactions in simplified environments. Our findings therefore raise concerns that such studies are prone to overestimate the effects of animal personality.

Consistent individual differences in sea lamprey (Petromyzon marinus) behaviour: Implications for control via trapping

Abstract We tested if consistent individual differences (CIDs) in the behaviour of sea lamprey (Petromyzon marinus) from the Laurentian Great Lakes could influence their vulnerability to trapping. The sea lamprey is invasive in the Upper Laurentian Great Lakes and the target of a binational control program. Trapping could be used for control if trapping efficiency is unbiased and effective. Our test involved comparing the behaviour of sea lamprey collected in the field from a trap (n = 42) at a barrier and electrofished (n = 9) downstream of the barrier. We quantified each individual's latency to exit an enclosure (a measure of exploration), proportion of time spent moving (a measure of general activity), and change in activity in response to a putative predator cue (a measure of boldness). CIDs were detected for each behaviour measured (intraclass correlations: 0.3–0.5). CIDs in behaviour also differed between trapped individuals and those collected downstream using electrofishing, irrespective of size, sex, and maturity status. Trapped individuals decreased their activity in response to a putative predator cue, while individuals collected using electrofishing increased their activity in response to the cue. Trapped individuals also tended to spend a greater proportion of time moving than individuals sampled downstream of the trap. However, the two samples of lamprey did not differ significantly in time taken to exit an enclosure. The behavioural differences between sea lamprey sampled from a trap and those sampled downstream of the trap suggest that CIDs in behaviour can influence an individual's vulnerability to trapping.

A preliminary investigation into personality and pain in dogs

Abstract Adherence to basic animal welfare standards involves effective monitoring and control of pain, especially in a veterinary setting. Assessment relies on behavioral and physiological indicators. However, individual differences in physiology mediate consistent individual differences in behavior, referred to as personality. Therefore, personality may confound measurements of pain. The current work is a preliminary investigation into whether extraversion and neuroticism are associated with differences in individual behavioral and physiological responses to pain. Twenty dogs were observed during recovery from routine castration in a clinical setting. Core temperature was recorded using infrared thermography on admission, 15 minutes after extubation and every 30 minutes thereafter, until the subject was collected by their owner. Behavior during recovery was scored using Short-Form Glasgow Composite Measure Pain Scale at the same intervals as infrared thermography readings. Personality was measured using Monash Canine Personality Questionnaire–Revised, and owners rated their dog's tolerance to pain on a 5-point Likert scale. Pain score did not have an association with eye temperature discrepancy or core temperature changes from control, indicating it may not predict affective response to pain. More highly extravert subjects had significantly higher pain scores ( P = 0.031), despite experiencing similar tissue damage. More extravert subjects showed significantly greater right eye temperature ( P = 0.035), suggesting hemispheric dominance. Neuroticism had no association with physiological or behavioral responses to pain. Finally, owners were not able to predict their dog's behavioral or physiological response to pain. These results indicate that personality may be a useful clinical tool for assessing individual differences in response to pain, whereas owners' ratings of their dog's response are not reliable.

Integrating thermal physiology within a syndrome: Locomotion, personality and habitat selection in an ectotherm

Abstract Physiology and temperature can both have a profound influence on behaviour and metabolism. Despite this, thermal physiology has rarely been considered within the animal personality framework, but could be an inherent mechanism maintaining consistent individual differences in behaviour, particularly in species that need to thermoregulate (i.e. ectotherms). Here, we present evidence for a thermal‐behavioural syndrome and detail how it is linked to variation in habitat selection in an Australian lizard, the delicate skink, Lampropholis delicata. We predicted that individuals would occur along a cold–hot continuum—analogues to the slow–fast continuum proposed by the pace‐of‐life hypothesis—whereby an individual's placement along a thermal physiological axis will correspond with their placement along a personality axis. We first tested the thermal‐behavioural syndrome by measuring the thermal preferences and optimal performance temperature of individual skinks and linking it to their activity, exploratory, social and boldness behaviours. In line with our predictions, we found that individuals with a “hot” thermal type performed optimally at higher temperatures, had faster sprint speeds and were more active, explorative and bold relative to “cold” thermal types. We then monitored each individual's habitat selection within an artificial environment containing three microhabitats differing in their thermal characteristics. We found that an individual's thermal type mediated their use of habitat, in which “hot” individuals utilized a hotter microhabitat more regularly than both “cold” and “intermediate” thermal types, suggesting that the thermal‐behavioural syndrome could drive ecological niche partitioning in this species. We envisage that the thermal‐behavioural syndrome concept is likely to extend to other study systems, particularly to ectothermic organisms that rely heavily on behavioural thermoregulation to maintain optimal body temperature. A plain language summary is available for this article.

Does increasing habitat complexity favour particular personality types of juvenile Atlantic salmon, Salmo salar?

The costs and benefits of a particular behavioural trait, such as boldness or aggression, may vary depending on the physical environment. We tested whether the common practice of adding physical structure (i.e. boulders) to streams to increase salmonid density has behavioural consequences, as open habitats are predicted to favour individuals that are more bold and aggressive. Wild young-of-the-year Atlantic salmon were captured from habitats of varying physical complexity and placed into seminatural stream enclosures for 11 days while their behaviour was observed and tested in both open and structurally complex environments. We found evidence for personality, or consistent individual behavioural differences across contexts, for avoidance and site attachment, with repeatabilities of 0.287 and 0.206, respectively, but not for activity or frequency of aggression. Fish were significantly more active and aggressive in the open habitats, and more site-attached in the complex habitats. Active and aggressive fish also grew more in the wild, while site-attached fish grew less in the wild, but more in the enclosures. However, contrary to our expectation, the complexity of the original habitat was not a significant predictor of personality. Our results suggest stream restorations involving increasing habitat complexity will alter the behaviour of young-of-the-year Atlantic salmon, but will not favour any particular personality types.

Temporal dynamics of the HPA axis linked to exploratory behavior in a wild European songbird (Parus major)

Variation in the reactivity of the endocrine stress axis is thought to underlie aspects of persistent individual differences in behavior (i.e. animal personality). Previous studies, however, have focused largely on estimating baseline or peak levels of glucocorticoids (CORT), often in captive animals. In contrast, the temporal dynamics of the HPA axis—how quickly it turns on and off, for example—may better indicate how an individual copes with stressors. Moreover, these HPA components might be correlated, thereby representing endocrine suites. Using wild-caught great tits (Parus major) we tested birds for exploratory behavior using a standardized novel environment assay that serves as a validated proxy for personality. We then re-captured a subset of these birds (n=85) and characterized four components of HPA physiology: baseline, endogenous stress response, a dexamethasone (DEX) challenge to estimate the strength of negative feedback, and an adrenocorticotropic hormone (ACTH) challenge to estimate adrenal capacity. We predicted that these four HPA responses would be positively correlated and that less exploratory birds would have a more rapid onset of the stress response (a CORT elevation during the baseline bleed) and weaker negative feedback (higher CORT after DEX). We found support for the first two predictions but not the third. All four components were positively correlated with each other and less exploratory birds exhibited an elevation in CORT during the baseline bleed (<3min from capture). Less exploratory birds, however, did not exhibit weaker negative feedback following the DEX challenge, but did exhibit weaker adrenal capacity. Together, our findings provide partial support for the hypothesis that the temporal reactivity of the HPA axis is linked with consistent individual differences in behavior, with more cautious (slower exploring) individuals exhibiting a faster CORT response.

A behavioural syndrome, but less evidence for a relationship with cognitive traits in a spatial orientation context

BackgroundAnimals show consistent individual behavioural differences in many species. Further, behavioural traits (personality traits) form behavioural syndromes, characterised by correlations between different behaviours. Mechanisms maintaining these correlations could be constrained due to underlying relationships with cognitive traits. There is growing evidence for the non-independence of animal personality and general cognitive abilities in animals, but so far, studies on the direction of the relationship between them revealed contradictory results. Still, it is hypothesised that individuals may exhibit consistent learning and decision styles. Fast behavioural types (consistently bolder and more active individuals) are expected to show faster learning styles. Slow behavioural types in contrast are assumed to learn slower but more accurately. This can be caused by a speed-accuracy trade-off that individuals face during decision making. We measured the repeatability of three personality and four spatial cognitive traits in adult Eurasian harvest mice (Micromys minutus). We analysed correlations among personality traits (behavioural syndrome). We further investigated the relationships between personality and spatial cognitive traits as a first step exploring the potential connection between personality and cognition in this species.ResultsOur results showed that exploration, activity and boldness were repeatable in adult mice. Spatial recognition measured in a Y Maze was also significantly repeatable, as well as spatial learning performance and decision speed. We found no repeatability of decision accuracy. Harvest mice showed a behavioural syndrome as we observed strong positive correlations between personality traits. The speed-accuracy trade-off was not apparent within, nor between individuals. Nevertheless, we found weak evidence for a relationship between personality and spatial cognitive traits as fast behavioural types learned a spatial orientation task faster than slow types, and shyer harvest mice made decisions quicker than bolder mice.ConclusionsGiven these correlations, our data provided some first insights into the relationship between personality and spatial cognitive traits in harvest mice and will hopefully stimulate more studies in this field.

Context‐dependent individual behavioral consistency in Daphnia

AbstractThe understanding of consistent individual differences in behavior, often termed “personality,” for adapting and coping with threats and novel environmental conditions has advanced considerably during the last decade. However, advancements are almost exclusively associated with higher‐order animals, whereas studies focusing on smaller aquatic organisms are still rare. Here, we show individual differences in the swimming behavior of Daphnia magna, a clonal freshwater invertebrate, before, during, and after being exposed to a lethal threat, ultraviolet radiation (UVR). We show consistency in swimming velocity among both mothers and daughters of D. magna in a neutral environment, whereas this pattern breaks down when exposed to UVR. Our study also, for the first time, illustrates how the ontogenetic development in swimming and refuge‐seeking behavior of young individuals eventually approaches that of adults. Overall, we show that aquatic invertebrates are far from being identical robots, but instead they show considerable individual differences in behavior that can be attributed to both ontogenetic development and individual consistency. Our study also demonstrates, for the first time, that behavioral consistency and repeatability, that is, something resembling “personality,” is context and state dependent in this zooplankter taxa.

Smaller and bolder prey snails have higher survival in staged encounters with the sea star Pisaster giganteus.

Temporally consistent individual differences in behavior, also known as animal personality, can have large impacts on individual fitness. Here, we explore the degree to which individual differences in anti-predator response (or boldness) influence survival rates in groups of snails Chlorostoma funebralis when they encounter a predatory sea star Pisaster giganteus. The snail C. funebralis shows consistent individual variation in predator response where some fearful snails actively flee bodies of water occupied by predators whereas bolder snails consistently do not. We show here that bold snails are significantly more likely to survive encounters with a predatory sea star and, somewhat counterintuitively, fearful snails actually suffer higher mortality rates. We also found that smaller snails and those occurring at higher experimental densities experienced higher per capita survival rates. Positive effects of prey boldness on survival are not uncommonly reported in the animal personality literature; however, such results are inconsistent with classic animal personality theory borrowed from the optimal foraging literature. The findings herein add to the growing body of evidence that consistent individual differences in behavior can impact predator–prey interactions and that boldness is potentially under positive predator-driven selection in some systems.

Fast-slow life history is correlated with individual differences in movements and prey selection in an aquatic predator in the wild.

Fast and slow life histories are proposed to covary with consistent individual differences in behaviour, but little is known whether it holds in the wild, where individuals experience natural fluctuations of the environment. We investigated whether individual differences in behaviour, such as movement traits and prey selection, are linked to variation in life-history traits in Eurasian perch (Perca fluviatilis) in the wild. Using high-resolution acoustic telemetry, we collected the positional data of fish in a whole natural lake and estimated individual movement traits by fitting a two-state correlated random walk model. Prey selection was inferred from stable isotope analysis using scale samples. Life-history traits were estimated by fitting a biphasic growth model to an individual growth trajectory back-calculated from scale samples. Life-history traits were correlated with behavioural traits such as movements and prey selection. Individuals with higher reproductive effort were found to switch more frequently between active and inactive modes and show greater reliance on prey from pelagic pathways (indicated by lower δ13 C). Further, individuals with faster juvenile growth were found to stay active for a longer time during the adult stage. Our results demonstrate the link between individual behavioural differences and fast-slow life-history traits under ecologically relevant conditions.

Metabolic rates, and not hormone levels, are a likely mediator of between‐individual differences in behaviour: a meta‐analysis

Summary Consistent individual differences in hormone levels and metabolic rates have been proposed to be potential state variables underlying consistent individual differences in behaviour (i.e. animal personality). However, it remains unclear whether either one alone or both of these potential state variables could be an underlying driver of animal personality. We address this question using meta‐analyses of published data from bird species. We hypothesized that state variables that mediate individual differences in behaviour would display similar or higher repeatability estimates than behavioural traits. To test this hypothesis, we quantified repeatability estimates of hormone levels, metabolic rates and behavioural traits. We found moderate to high mean repeatability estimates for both metabolic rates and behavioural traits, but low repeatability estimates for hormone levels. These findings indicate that metabolic rates likely represent an important mechanism for generating adaptive personality differences in behaviour. We also show that: (i) for hormones and behaviour, repeatability decreased with increasing interval time between two measurements; (ii) males and females differed in repeatability for behavioural traits; (iii) stress‐induced hormone levels were more repeatable than baseline levels. Future studies are now required to determine the direction of the association between metabolic rates and behavioural traits. At the same time, these studies should try to investigate which of the proposed mechanisms is responsible for the relationship between state variable and state‐dependent behaviour. In addition, we encourage researchers to report the coefficient of variation for between‐individual variance (CVB) along with repeatability estimates because these two indices carry different information. We discuss how CVB may better facilitate future comparative studies, including meta‐analyses. A lay summary is available for this article.

Personality and urbanization: behavioural traits and DRD4 SNP830 polymorphisms in great tits in Barcelona city

Most examples of adaptation to the urban environment relate to plasticity processes rather than to natural selection. Personality, however, defined as consistent individual differences in behaviour ...

Stress-induced peak (but not resting) metabolism correlates with mating display intensity in male guppies.

Recent empirical and conceptual papers have highlighted the potential for metabolism to act as a proximate mechanism for behavior that could explain animal personality (consistency over time). Under this hypothesis, individuals with consistently high levels of behavioral activity should also have high resting metabolic rate (RMR) as it can reflect capacity to process food and generate energy. We tested for the predicted positive covariance between RMR and three behaviors that differ in energy demands in 30 male guppies, using multivariate mixed models; we repeatedly measured their activity (10 times each), courtship displays (nine times), voracity (10 times), and metabolism (four‐times). Resting metabolic rate (measured overnight in respirometry trials) did not consistently differ among males, whereas initial peak metabolism measured during those same trials (R = 0.42), and all behaviors were repeatable (R = 0.33–0.51). RMR declined over time suggesting habituation to the protocol, whereas peak metabolism did not. Initial peak metabolism was negatively correlated with courtship display intensity, and voracity was positively correlated with activity, but all other among‐individual correlations were not significant. We conclude that RMR does not provide a proximate explanation for consistent individual differences in behavior in male guppies, and therefore the potential for independent evolution of these physiological and behavioral traits seems possible. Finally, we identify peak metabolism as a potential measure of the stress response to confinement, which highlights the value of considering various aspects of metabolic rates recording during respirometry trials.

RETRACTED ARTICLE: Prolonged food restriction decreases body condition and reduces repeatability in personality traits in web-building spiders

Variation in state, which is any factor that alters the value of decision options, is likely one of the most common drivers of personality differences. However, the general relationship between individuals’ body state and various personality metrics/average behavioral type, repeatability of behavior, and behavioral syndrome structure is still poorly resolved. Here, we manipulate body condition in three spider species (Agelenopsis aperta, Latrodectus hesperus, and Anelosimus studiosus) using contrasting feeding schedules. We then assessed the effects of historic feeding regime on individuals’ body condition, boldness, and foraging aggressiveness. We further assessed the effects of feeding regimes on the repeatability of boldness and aggressiveness and the presence/absence of correlations between these two traits. We found that feeding treatment impacted individuals’ average boldness and aggressiveness in two species (A. aperta and A. studiosus). We also noted that among-individual variance in both boldness and aggressiveness was severely reduced when A. aperta and A. studiosus were subjected to prolonged food restriction, steeply reducing repeatability in these traits. Finally, we noted that correlations between boldness and foraging aggressiveness were detectable only in one case, revealing no compelling relationship between food restriction and the presence/absence of behavioral correlations. Taken together, our results suggest that food restriction has only weak, circumstantial effects on individuals’ average personality type and the correlations between behavioral traits. However, there appears to be a robust positive relationship between food availability and the signature of consistent individual differences in behavior. Under laboratory conditions, we found that lower feeding rates sharply decreased the repeatability of aggressiveness and boldness in two spider species. In doing so, we provide the second body of evidence suggesting that a highly prevalent and ecologically relevant state variable, higher body condition, can increase the repeatability of foraging-related behavioral traits. Additionally, under some feeding regimes, we found that hunger levels could alter the average individual aggressiveness and boldness but not correlations between these traits. This work highlights the importance of state variables such as hunger in eroding behavioral repeatability, the defining trait of personality.