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Recent evidence suggests that individuals differ in foraging tactics and this variation is often linked to an individual's behavioural type (BT). Yet, while foraging typically comprises a series of search and handling steps, empirical investigations have rarely considered BT‐dependent effects across multiple stages of the foraging process, particularly in natural settings.In our long‐term sleepy lizard (Tiliqua rugosa) study system, individuals exhibit behavioural consistency in boldness (measured as an individual's willingness to approach a novel food item in the presence of a threat) and aggressiveness (measured as an individual's response to an 'attack' by a conspecific dummy). These BTs are only weakly correlated and have previously been shown to have interactive effects on lizard space use and movement, suggesting that they could also affect lizard foraging performance, particularly in their search behaviour for food.To investigate how lizards' BTs affect their foraging process in the wild, we supplemented food in 123 patches across a 120‐ha study site with three food abundance treatments (high, low and no‐food controls). Patches were replenished twice a week over the species' entire spring activity season and feeding behaviours were quantified with camera traps at these patches. We tracked lizards using GPS to determine their home range (HR) size and repeatedly assayed their aggressiveness and boldness in designated assays.We hypothesised that bolder lizards would be more efficient foragers while aggressive ones would be less attentive to the quality of foraging patches. We found an interactive BT effect on overall foraging performance. Individuals that were both bold and aggressive ate the highest number of food items from the foraging array. Further dissection of the foraging process showed that aggressive lizards in general ate the fewest food items in part because they visited foraging patches less regularly, and because they discriminated less between high and low‐quality patches when revisiting them. Bolder lizards, in contrast, ate more tomatoes because they visited foraging patches more regularly, and ate a higher proportion of the available tomatoes at patches during visits.Our study demonstrates that BTs can interact to affect different search and handling components of the foraging process, leading to within‐population variation in foraging success. Given that individual differences in foraging and movement will influence social and ecological interactions, our results highlight the potential role of BT's in shaping individual fitness strategies and population dynamics. [ABSTRACT FROM AUTHOR]

Host behavior and parasite infection reciprocally interact, but this dynamic is rarely studied experimentally in the field with multiple behaviors. We investigated the interplay between parasitism and host behavior via an in situ experimental tick infestation of a wild population of sleepy lizards, Tiliqua rugosa. Using Bayesian models, we assessed the relationship between experimental infestation and lizard aggression and boldness before and after infestation. First, we tested whether lizard aggression and boldness prior to infestation predicted the probability of tick attachment in the infestation experiment. Second, we evaluated whether experimental infestation affected subsequent lizard aggression and boldness. We found that aggression and boldness related interactively with infestation: for unaggressive lizards, higher boldness was associated with reduced experimental infestation success, but the opposite occurred for aggressive individuals. Second, increased tick infestation did not affect post-infestation aggression, but tended to increase boldness. Taken together, these results highlight the potential for feedbacks between parasites and multi-dimensional host behaviors. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2007.05.008 Byline: David L. Sinn, Samuel D. Gosling, Natalie A. Moltschaniwskyj Abstract: Animals often differ from one another in their willingness to take risks in a number of functional contexts related to fitness (e.g. mating, dispersal, and foraging behaviour). Although several studies have reported life history correlates and selective consequences of this variation in shy/bold behaviour, little attention has been paid to developmental processes resulting in shy/bold phenotypes. Here, we present a lifetime developmental study of shy/bold behaviour in dumpling squid, Euprymna tasmanica. Behaviour was measured in two test contexts, a threat and a feeding test, at five times across the entire life span. Across test contexts, shy/bold behaviour was not correlated at any age; while within a test context, individual shy/bold phenotypes were consistent both before and after sexual maturity. During sexual maturity, different phenotypes displayed different amounts of developmental variation; shyer animals were more plastic in feeding tests, while bolder animals were more plastic in threat ones. Our results suggest that for some animals shy/bold behaviour throughout development is uncorrelated across different contexts related to risk, while within a context, there may still be developmental constraints to changing shy/bold behaviour. This constraint within a functional context, however, may be phenotype-specific, with some phenotypes able to change more than others. These results indicate that a greater understanding of developmental pathways is needed to determine whether shy/bold phenotypes per se are the sole focus of selection. Differences in developmental plasticity between shy/bold phenotypes may also confer differential fitness in fluctuating environments. Author Affiliation: (a) School of Aquaculture, University of Tasmania, Australia (a ) School of Plant Science, University of Tasmania, Australia (a ) Department of Psychology, University of Texas, U.S.A. Article History: Received 24 November 2006; Revised 31 January 2007; Accepted 14 May 2007 Article Note: (miscellaneous) MS. number: 9188R

Personality traits are a major class of behavioral variation often observed within populations of animals. However, little is known of the integration between personality and an individual's underlying biology. To address this, the authors measured personality traits in squid (Euprymna tasmanica) in 2 contexts while also describing trait correlates with biological parameters. Four traits (shy avoidance-bold aggression, activity, bury persistence, and reactivity) were reliably measured; however, trait expression between contexts was not correlated and thus was context-specific. Trait variation was not a function of gender or of somatic or reproductive condition but was explained partially by a squid's sexual maturity and its size. Results are discussed in terms of the interplay between personality variation and resulting life history strategies in animals.

During their 3rd week of life, 73 Octopus bimaculoides were observed to test whether discrete behaviors could be grouped reliably to reflect dimensions of temperament. Frequencies of behaviors during Week 3 were subjected to principal-components analysis (PCA), resulting in 4 components (active engagement, arousal/readiness, aggression, and avoidance/disinterest) that explain 53% of the variance. Levels of temperamental traits were then evaluated for 37 octopuses using composite scores at 3 time points across the first 9 weeks of life. Profile analysis revealed significant change for the testing group as a whole in trait expression levels from Week 3 to Week 6. Results also suggest a significant effect of relatedness on developing temperamental profiles of octopuses. Discussion focuses on how results apply to the life history of O. bimaculoides and what temperament can reveal about adaptive individuality in a protostome.

Individual variation in movement is profoundly important for fitness and offers key insights into the spatial and temporal dynamics of populations and communities. Nonetheless, individual variation in fine‐scale movement behaviours is rarely examined even though animal tracking devices offer the long‐term, high‐resolution, repeatable data in natural conditions that are ideal for studying this variation. Furthermore, of the few studies that consider individual variation in movement, even fewer also consider the internal traits and environmental factors that drive movement behaviour which are necessary for contextualising individual differences in movement patterns.In this study, we GPS tracked a free‐ranging population of sleepy lizards Tiliqua rugosa, each Austral spring over 5 years to examine consistent among‐individual variation in movement patterns, as well as how these differences were mediated by key internal and ecological factors.We found that individuals consistently differed in a suite of weekly movement traits, and that these traits strongly covaried among‐individuals, forming movement syndromes. Lizards fell on a primary movement continuum, from 'residents' that spent extended periods of time residing within smaller core areas of their home range, to 'explorers' that moved greater distances and explored vaster areas of the environment.Importantly, we also found that these consistent differences in lizard movement were related to two ecologically important animal personality traits (boldness and aggression), their sex, key features of the environment (including food availability, and a key water resource), habitat type and seasonal variation (cool/moist vs. hot/drier) in environmental conditions.Broadly, these movement specialisations likely reflect variation in life‐history tactics including foraging and mating tactics that ultimately underlie key differences in space use. Such information can be used to connect phenotypic population structure to key ecological and evolutionary processes, for example social networks and disease‐transmission pathways, further highlighting the value of examining individual variation in movement behaviour. [ABSTRACT FROM AUTHOR]

Translocation of endangered animals is common, but success is often variable and/or poor. Despite its intuitive appeal, little is known with regards to how individual differences amongst translocated animals influence their post-release survival, growth, and reproduction. We measured consistent pre-release responses to novelty in a familiar environment (boldness; repeatability = 0.55) and cortisol response in a group of captive-reared Tasmanian devils, currently listed as 'Endangered' by the IUCN. The devils were then released at either a hard- or soft-release site within their mothers' population of origin, and individual growth, movement, reproduction (females only), and survival across 2-8 months post-release was measured. Sex, release method, cohort, behavior, and cortisol response did not affect post-release growth, nor did these factors influence the home range size of orphan devils. Final linear distances moved from the release site were impacted heavily by the release cohort, but translocated devils' movement overall was not different from that in the same-age wild devils. All orphan females of reproductive age were subsequently captured with offspring. Overall survival rates in translocated devils were moderate (∼42%), and were not affected by devil sex, release method, cohort, release weight, or pre-release cortisol response. Devils that survived during the study period were, however, 3.5 times more bold than those that did not (effect size r = 0.76). Our results suggest that conservation managers may need to provide developmental conditions in captivity that promote a wide range of behaviors across individuals slated for wild release. Zoo Biol. 33:36-48, 2014. © 2013 Wiley Periodicals Inc. [ABSTRACT FROM AUTHOR]