Find research datasets worth reusing

Data from: The costs of kleptoparasitism: a study of mixed-species seabird breeding colonies

Mixed-species assemblages are common in nature, providing mutual benefits to associating species including anti-predator advantages or resource facilitation. However, associating with other species may also impose costs through kleptoparasitism (food theft). Identification of these costs, and how they vary when different species breed alongside one another, is essential to understand the payoffs of mixed-species assemblages. We explore the costs of kleptoparasitism for greater crested terns Thalasseus bergii provisioning offspring at a single-species colony, where individuals suffer kleptoparasitism from conspecifics, and at a mixed colony where terns breed alongside Hartlaub's gulls Chroicocephalus hartlaubii and are vulnerable to both intra- and interspecific kleptoparasitism. Gull presence increased both kleptoparasitic attacks and the proportion of prey lost or stolen during provisioning, relative to the single-species colony. Provisioning adults suffered additional energetic costs in response to gull kleptoparasitism, requiring more attempts to deliver prey, taking longer to do so, and swallowing more prey (to the detriment of their offspring). Gulls also increased the duration of tern vulnerability to kleptoparasitism, because they continued to steal food from adults and chicks after precocial chicks left the nest, when intraspecific kleptoparasitism is negligible. Terns breeding in a mixed colony therefore suffer direct and indirect costs through decreased provisioning and increased provisioning effort, which may ultimately impact reproductive success, resulting in colony decline where kleptoparasitism is frequent. This study illustrates how forming a mixed-species seabird breeding assemblage has costs as well as benefits, potentially fluctuating between a parasitic and a mutualistic relationship.

opencc-zeroDec 2014View details →

Data from: Breeding system evolution influenced the geographic expansion and diversification of the core Corvoidea (Aves: Passeriformes)

Birds vary greatly in their life-history strategies, including their breeding systems, which range from brood parasitism to a system with multiple non-breeding helpers at the nest. By far the most common arrangement, however, is where both parents participate in raising the young. The traits associated with parental care have been suggested to affect dispersal propensity and lineage diversification, but to date tests of this potential relationship at broad temporal and spatial scales have been limited. Here, using data from a globally distributed group of corvoid birds in concordance with state-dependent speciation and extinction models, we suggest that pair breeding is associated with elevated speciation rates. Estimates of transition between breeding systems imply that cooperative lineages frequently evolve biparental care, whereas pair breeders rarely become cooperative. We further highlight that these groups have differences in their spatial distributions, with pair breeders over-represented on islands, and cooperative breeders mainly found on continents. Finally, we find that speciation rates appear to be significantly higher on islands compared to continents. These results imply that the transition from cooperative breeding to pair breeding was likely a significant contributing factor facilitating dispersal across tropical archipelagos, and subsequent world-wide phylogenetic expansion among the core Corvoidea.

Data from: Genomic characterisation of the indigenous Irish Kerry cattle breed

Kerry cattle are an endangered landrace heritage breed of cultural importance to Ireland. In the present study we have used genome-wide SNP array data to evaluate genomic diversity within the Kerry population and between Kerry cattle and other European breeds. Patterns of genetic differentiation and gene flow among breeds using phylogenetic trees with ancestry graphs highlighted historical gene flow from the British Shorthorn breed into the ancestral population of modern Kerry cattle. Principal component analysis (PCA) and genetic clustering emphasised the genetic distinctiveness of Kerry cattle relative to comparator British and European cattle breeds. Modelling of genetic effective population size (Ne) revealed a demographic trend of diminishing Ne over time and that recent estimated Ne values for the Kerry breed may be less than the threshold for sustainable genetic conservation. In addition, analysis of genome-wide autozygosity (FROH¬) showed that genomic inbreeding has increased significantly during the 20 years between 1992 and 2012. Finally, signatures of selection revealed genomic regions subject to natural and artificial selection as Kerry cattle adapted to the climate, physical geography and agro-ecology of southwest Ireland.

opencc-zeroDec 2018View details →

Data from: Haemosporidian parasites depress breeding success and plumage coloration in female barn swallows (Hirundo rustica)

Parasites are major effectors of natural selection and also play a role in sexual selection processes. Haemosporidian blood parasites are common in vertebrates and have been shown to vary in their effects depending on both the parasite and host species, on the host trait investigated as well as on host condition and stage of infection. Here we investigated infection of adult barn swallows (Hirundo rustica) by Plasmodium, Leucocytozoon and Haemoproteus species during the chronic stage of infection and the consequences for host fitness traits. Prevalence was higher than 10% only for Plasmodium. Chronic stage infection by Plasmodium was associated with reduced female breeding success, but did not affect breeding dates. Infection did not affect the expression of male secondary sexual traits (tail length and melanin‐based plumage coloration), but was associated with paler coloration of females. Finally, we found a negative effect of infection by Plasmodium on feather growth rate in older but not in yearling individuals. Because feathers are moulted during wintering in sub‐Saharan Africa where infection of barn swallows by Plasmodium occurs, our results suggest that male secondary sexual traits have little potential to reveal acute‐stage infection whereas plumage coloration of females may advertise their infection status. In addition, these results suggest that infection by Plasmodium can influence the course of plumage moult. Thus, our results add to the observations of negative effects of haemosporidian infection on fitness traits in birds and provides evidence that these effects can vary among traits and in relation to age and sex.

Data from: QuLinePlus: extending plant breeding strategy and genetic model simulation to cross-pollinated populations – case studies in forage breeding

Plant breeders are supported by a range of tools that assist them to make decisions about the conduct or design of plant breeding programs. Simulations are a strategic tool that enable the breeder to integrate the multiple components of a breeding program into a number of proposed scenarios that are compared by a range of statistics measuring the efficiency of the proposed systems. A simulation study for the trait growth score compared two major strategies for breeding forage species, among half-sib family selection and among and within half-sib family selection. These scenarios highlighted new features of the QuLine program, now called QuLinePlus, incorporated to enable the software platform to be used to simulate breeding programs for cross pollinated species. Each strategy was compared across three levels of HS family mean heritability (0.1, 0.5 and 0.9), across three sizes of the initial parental population (10, 50, and 100), and across three genetic effects models (fully additive model, a mixture of additive, partial and over dominance model, and a mixture of partial dominance and over dominance model). Among and within half-sib selection performed better than among half-sib selection for all scenarios. The new tools introduced into QuLinePlus should serve to accurately compare among methods and provide direction on how to achieve specific goals in the improvement of plant breeding programs for cross breeding species.

opencc-zeroDec 2014View details →

Data from: Body reserves influence allocation to immune responses in capital breeding female northern elephant seals

Mounting an immune response requires substantial energy. Ecological immunology theory predicts allocation trade-offs between reproductive effort and immune responses under conditions of energy limitation. Little is known about the impact of capital breeding strategies on energy allocation to immune function in mammals. Northern elephant seals (NES) forage in the marine environment, breed in dense terrestrial colonies and exhibit high rates of energy expenditure for lactation while fasting. Body reserves strongly influence reproductive effort and lactation requires elevation of plasma cortisol for energy mobilization. We characterized immune response by measuring a suite of immune markers including cytokines, an acute phase protein, and immunoglobulins early and late in breeding and moult haul-outs in 197 samples from 129 female NES. We explored potential impacts of breeding, body condition and plasma cortisol on immune function. Immune responses were greater and more varied during breeding. Adiposity had positive associations with innate immune responses across all life-history stages. Body mass had positive associations with both adaptive and innate immune responses early in fasts. Females with lower fat reserves showed reduced innate immune responses at the end of lactation. Immunoglobulin E, a marker of immune response to parasitic infection, exhibited a significant negative association with cortisol across all life-history stages. These data suggest that breeding carries an immune cost and provide evidence for allocation trade-offs between immune function and breeding effort. These trade-offs may reflect a compromise between immune costs inherent in colonial breeding and energetic limitations that arise in use of capital breeding strategies. Variation in evidence for immunosuppressive effects of cortisol suggests that decoupling of these effects may be limited to specific aspects of the immune response during terrestrial fasting. Immune responses that are required for survival may be modulated relative to the energetic demands required for successful reproduction.

Data from: Partial incubation during egg laying reduces eggshell microbial loads in a temperate‐breeding passerine

Incubation prior to clutch completion may be adaptive if it maintains egg viability by inhibiting eggshell microbial growth, thus reducing the likelihood that the embryo becomes infected. To test this hypothesis, we examined the effect of partial incubation during egg laying on eggshell microbial loads in eastern bluebirds Sialia sialis breeding at a temperate‐zone site. We sampled eggshell microbes prior to and following four days of exposure to either partial incubation during the laying period or ambient environmental conditions without incubation (experimental eggs). Microbial colony counts declined significantly for eggs left in the nest during the laying period but did not vary significantly for eggs exposed to ambient conditions. Initial microbial loads were more similar to those previously reported from tropical than temperate environments, and microbes from potentially pathogenic groups were detected on 88% of first‐laid eggs on the day of laying. Egg viability was maintained when eggs were held indoors for four days without incubation but declined sharply thereafter. Our results suggest that partial incubation during egg laying may enhance egg viability in eastern bluebirds by reducing eggshell microbial loads; these effects appear stronger than those usually reported from the temperate zone.

opencc-zeroDec 2012View details →

Data from: Extra-group mating increases inbreeding risk in a cooperatively breeding bird

In many cooperatively-breeding species females mate extra-group, the adaptive value of which remains poorly understood. One hypothesis posits that females employ extra-group mating to access mates whose genotypes are more dissimilar to their own than their social mates', so as to increase offspring heterozygosity. We test this hypothesis using life-history and genetic data from 36 cooperatively-breeding white-browed sparrow weaver (Plocepasser mahali) groups. Contrary to prediction, a dominant female's relatedness to her social mate did not drive extra-group mating decisions and, moreover, extra-group mating females were significantly more related to their extra-group sires than their social mates. Instead, dominant females were substantially more likely to mate extra-group when paired to a dominant male of low heterozygosity, and their extra-group mates (typically dominants themselves) were significantly more heterozygous than the males they cuckolded. The combined effects of mating with extra-group males of closer relatedness but higher heterozygosity resulted in extra-group-sired offspring that were no more heterozygous than their within-group-sired half-siblings. Our findings are consistent with a role for male-male competition in driving extra-group mating and suggest that the local kin structure typical of cooperative breeders could counter potential benefits to females of mating extra-group by exposing them to a risk of inbreeding.

Data from: Cohabitation with farm animals rather than breeding effort increases the infection with feather-associated bacteria in the barn swallow Hirundo rustica

Feather-associated bacteria are widespread inhabitants of avian plumage. However, the determinants of the between-individual variation in plumage bacterial loads are less well understood. Infection intensities can be determined by ecological factors, such as breeding habitat, and can be actively regulated by hosts via preening. Preening, yet, is a resource intensive activity, and thus might be traded-off against reproductive investment in breeding birds. Here, we studied barn swallows Hirundo rustica to assess the bacterial cost of reproduction in relation to nesting site micro-habitats. Barn swallows prefer to breed in the company of large-sized farm animals, although the presence of mammalian livestock in barns assures a warm and humid micro-climate that favours bacterial proliferation. Thus, we experimentally manipulated brood sizes of birds breeding in barns with, or without, farm animals and measured total cultivable bacteria (TCB) and feather-degrading bacteria (FDB) from the plumage. We found that the abundance of feather-associated bacteria (i.e. both TCB and FDB) in females, but not males, breeding in barns with livestock were significantly higher than in conspecifics breeding in empty barns. Plumage bacterial loads, however, were not affected by brood size manipulations in either sex. In addition, we report a negative relationship between both TCB and FDB and hatching date in females, and several sex and seasonal differences in plumage bacterial abundances. Our study is the first to show that breeding micro-habitat (i.e. livestock co-tenancy) has consequences for the abundance of feather-associated bacteria.

opencc-zeroDec 2014View details →

Data from: Using branch-and-bound algorithms to optimize selection of a fixed-size breeding population under a relatedness constraint

Tree breeders often face the challenge of conserving genetic diversity, while at the same time maximizing response to selection. When selecting advanced-generation breeding populations, the best-performing candidates will quite often be closely related and selecting them without consideration of their relatedness will very quickly erode genetic diversity. Optimal selection will not completely avoid kinship, but rather maximize gain while imposing a constraint on average relatedness. Genetic contributions are most easily optimized if breeders can manage a real, continuous distribution of contributions from parents. While generally possible when establishing seed orchards, unequal contributions to a breeding population may present difficult and time-consuming operational constraints. In these situations, a specified number of parents contributing equally may be a preferred configuration for the breeding population. Here we formulate the selection of a fixed-size breeding population while imposing a constraint on relatedness of the population members. The problem is expressed as a Mixed Integer Quadratically Constrained Optimization (MIQCO) and solved using branch-and-bound techniques (BB). An open-source solver, dsOpt, was developed and embedded into a user-friendly tool, OPSEL, designed to simplify the process of optimizing selection of breeding populations. Case studies optimizing selection of breeding populations for Scots pine and loblolly pine illustrate the superiority of the BB solution compared with selection from ranked lists with restrictions on numbers of genotypes contributed by each full-sib family, and with solutions from GENCONT, a publically available optimum selection program using an algorithm with Lagrangian multipliers. The case studies also illustrate the extreme differences that can occur with respect to time required to confirm the optimality of solutions found by BB.

opencc-zeroDec 2018View details →

Data from: Examining carry‐over effects of winter habitat on breeding phenology and reproductive success in prairie warblers (Setophaga discolor)

Winter habitat quality can influence breeding phenology and reproductive success of migratory birds. Using stable isotope ratios of carbon (δ13C) from bird claws and red blood cells collected in Massachusetts, USA, we assessed if winter habitat occupancy carried over to affect prairie warbler (Setophaga discolor) breeding arrival dates, body condition upon arrival, pairing success, first-egg dates, and reproductive success. In two of three years (in 2011 and 2012, but not in 2013), after-second-year (ASY) males wintering in drier habitat, as indicated by enriched δ13C values, arrived later on the breeding grounds. Based on the North Atlantic Oscillation index, there was likely less rainfall in the Caribbean wintering grounds during the winters of 2011 and 2012 compared to the winter of 2013, suggesting increased winter rainfall in 2013 may have diminished the influence of winter habitat occupancy on arrival date. We did not find any effects of winter habitat on breeding season phenomena for second-year (SY) males or females, but our sample sizes for these age/sex classes were relatively low. Although winter habitat quality influenced arrival dates of ASY males, there was no evidence that it affected reproductive performance, perhaps because of high rates of nest depredation in our system. Our study adds to a growing body of research that shows the influence of carry-over effects can differ among species and within populations, and also can be modulated by other environmental conditions. This information enriches our understanding of the role of carry-over effects in population limitation for migratory birds.

Data from: Age, condition and dominance-related sexual ornament size before and during the breeding season in the black grouse Lyrurus tetrix

Male ornaments function as honest cues of male quality in many species and are subject to intra- and intersexual selection. These ornaments are generally studied during peak expression, however their size outside the breeding season may determine ultimate ornament size and costliness, and as such reproductive success. We investigated whether male black grouse Lyrurus tetrix eye comb size was related to age, condition and measures of male dominance before and during the breeding season. Total combined eye comb size began to increase ~70 days before the start of the breeding season. Adult males (aged ≥ 2 years old) had consistently larger eye combs than younger males (1 year old) both before and during the breeding season. Heavier and more dominant adult males (attending the lek more frequently and successfully reproducing) had larger eye combs. For younger males, those that were heavier had larger eye combs. Additionally, males that spent more time on the lek showed increased eye comb size as the breeding season approached. Overall we find that ornament size is positively related to dominance and condition before and during the breeding season. Since dominance is accrued through year-round interactions in many species, the ability to maintain larger signals over prolonged periods,

Data from: Spring weather conditions influence breeding phenology and reproductive success in sympatric bat populations.

1. Climate is known to influence breeding phenology and reproductive success in temperate zone bats, but long-term population level studies and interspecific comparisons are rare. 2. Investigating the extent to which intrinsic (i.e. age), and extrinsic (i.e. spring weather conditions), factors influence such key demographic parameters as the proportion of females becoming pregnant, or completing lactation, each breeding season, is vital to understanding of bat population ecology and life-history traits. 3. Using data from twelve breeding seasons (2006 - 2017), encompassing the reproductive histories of 623 Myotis daubentonii and 436 M. nattereri adult females, we compare rates of recruitment to the breeding population, and show that these species differ in their relative sensitivity to environmental conditions and climatic variation, affecting annual reproductive success at the population level. 4. We demonstrate that i) Spring weather conditions influence breeding phenology, with warm, dry and calm conditions leading to earlier parturition dates and advanced juvenile development, whilst cold, wet and windy weather delays birth timing and juvenile growth, ii) Reproductive rates in first-year females are influenced by spring weather conditions in that breeding season and in the preceding breeding season when each cohort was born. Pregnancy and lactation rates were both higher when favourable spring foraging conditions were more prevalent, iii) Reproductive success increases with age in both species, but at different rates, iv) Reproductive rates were consistently higher, and showed less inter-annual variation, in second-year and older M. daubentonii (mean 91.55% ± 0.05 SD) than M. nattereri (mean 72.74% ± 0.15 SD), v) Estimates of reproductive success at the population level were highly correlated with the size of the juvenile cohort recorded each breeding season. 5. Improving understanding of the influence of environmental conditions, especially extreme climatic fluctuations, and the identification of critical periods (i.e. spring for reproductive female bats in temperate zones), which have disproportionate and lasting impacts on breeding phenology and reproductive success at a population level, is critical for improving predictions of the likely impact of climate change on bat populations.

opencc-zeroJun 2019View details →

Data from: Heritabilities, social environment effects and genetic correlations of social behaviours in a cooperatively breeding vertebrate

Social animals interact frequently with conspecifics, and their behaviour is influenced by social context, environmental cues and the behaviours of interaction partners, allowing for adaptive, flexible adjustments to social encounters. This flexibility can be limited by part of the behavioural variation being genetically determined. Furthermore, behaviours can be genetically correlated, potentially constraining independent evolution. Understanding social behaviour thus requires carefully disentangling genetic, environmental, maternal and social sources of variations as well as the correlation structure between behaviours. Here, we assessed heritability, maternal, common environment and social effects of eight social behaviours in Neolamprologus pulcher, a cooperatively breeding cichlid. We bred wild-caught fish in a paternal half-sibling design and scored ability to defend a resource against conspecifics, to integrate into a group and the propensity to help defending the group territory ('helping behaviour'). We assessed genetic, social and phenotypic correlations within clusters of behaviours predicted to be functionally related, namely 'competition', 'aggression', 'aggression-sociability', 'integration' and 'integration-help'. Helping behaviour and two affiliative behaviours were heritable, whereas there was little evidence for a genetic basis in all other traits. Phenotypic social effects explained part of the variation in a sociable and a submissive behaviour, but there were no maternal or common environment effects. Genetic and phenotypic correlation within clusters were mostly positive. A group's social environment influenced covariances of social behaviours. Genetic correlations were similar in magnitude but usually exceeding the phenotypic ones, indicating that conclusions about the evolution of social behaviours in this species could be provisionally drawn from phenotypic data in cases where data for genetic analyses are unobtainable.

Data from: Selective breeding and selection mapping using a novel wild-derived heterogeneous stock mice revealed two closely-linked loci for tameness

Tameness is a major behavioral factor for domestication, and can be divided into two potential components: motivation to approach humans (active tameness) and reluctance to avoid humans (passive tameness). We identified genetic loci for active tameness through selective breeding, selection mapping, and association analysis. In previous work using laboratory and wild mouse strains, we found that laboratory strains were predominantly selected for passive tameness but not active tameness during their domestication. To identify genetic regions associated with active tameness, we applied selective breeding over 9 generations for contacting, a behavioural parameter strongly associated with active tameness. The prerequisite for successful selective breeding is high genetic variation in the target population, so we established and used a novel resource, wild-derived heterogeneous stock (WHS) mice from eight wild strains. The mice had genetic variations not present in other outbred mouse populations. Selective breeding of the WHS mice increased the contacting level through the generations. Selection mapping was applied to the selected population using a simulation based on a non-selection model and inferred haplotype data derived from single-nucleotide polymorphisms. We found a genomic signature for selection on chromosome 11 containing two closely linked loci.

Data from: Long term on-farm participatory maize breeding by stratified mass selection retains molecular diversity while improving agronomic performance

Modern maize breeding programs gave rise to genetically uniform varieties that can affect maize's capacity to cope with increasing climate unpredictability. Maize populations, genetically more heterogeneous, can evolve and better adapt to a broader range of edaphic-climatic conditions. These populations usually suffer from low yields; it is therefore desirable to improve their agronomic performance while maintaining their valuable diversity levels. With this objective, a long-term participatory breeding/on-farm conservation program was established in Portugal. In this program maize populations were subject to stratified mass selection. The current work aims to estimate the effect of on-farm stratified mass selection on the agronomic performance, quality, and molecular diversity of two historical maize populations. Multi-location field trials, comparing the initial populations with the derived selection cycles, showed that this selection methodology led to agronomic improvement for one of the populations. The molecular diversity analysis, using microsatellites, revealed that overall genetic diversity in both populations was maintained throughout selection. The comparison of quality parameters between the initial populations and the derived selection cycles was done using kernel from a common garden experiment. This analysis showed that the majority of the quality traits evaluated progressed erratically over time. In conclusion, this breeding approach, through simple and low-cost methodologies, proved to be an alternative strategy for genetic resources' on-farm conservation.

Data from: Testing the heat dissipation limit theory in a breeding passerine

The maximum work rate of animals has recently been suggested to be determined by the rate at which excess metabolic heat generated during work can be dissipated (heat dissipation limitation theory; HDL). As a first step towards testing this theory in wild animals, we experimentally manipulated brood size in breeding marsh tits (Poecile palustris) to change their work rate. Parents feeding nestlings generally operated at above-normal body temperatures. Body temperature in both males and females increased with maximum ambient temperature and with manipulated work rate, sometimes even exceeding 45 °C, which is close to suggested lethal levels for birds. Such high body temperatures have previously only been described for birds living in hot and arid regions. Thus, reproductive effort in marsh tits may potentially be limited by the rate of heat dissipation. Females had lower body temperatures, a possible consequence of their brood patch serving as a thermal window facilitating heat dissipation. Because increasing body temperatures are connected to somatic costs, we suggest that the HDL theory may constitute a possible mediator of the trade-off between current and future reproduction. It follows that globally increasing, more stochastic, ambient temperatures may restrict the capacity for sustained work of animals in the future.

opencc-zeroDec 2015View details →

Data from: Delayed dispersal and the costs and benefits of different routes to independent breeding in a cooperatively breeding bird

Why sexually mature individuals stay in groups as nonreproductive subordinates is central to the evolution of sociality and cooperative breeding. To understand such delayed dispersal, its costs and benefits need to be compared with those of permanently leaving to float through the population. However, comprehensive comparisons, especially regarding differences in future breeding opportunities, are rare. Moreover, extraterritorial prospecting by philopatric individuals has generally been ignored, even though the factors underlying this route to independent breeding may differ from those of strict philopatry or floating. We use a comprehensive predictive framework to explore how various costs, benefits and intrinsic, environmental and social factors explain philopatry, prospecting, and floating in Seychelles warblers (Acrocephalus sechellensis). Not only floaters more likely obtained an independent breeding position before the next season than strictly philopatric individuals, but also suffered higher mortality. Prospecting yielded similar benefits to floating but lower mortality costs, suggesting that it is overall more beneficial than floating and strict philopatry. While prospecting is probably individual-driven, although limited by resource availability, floating likely results from eviction by unrelated breeders. Such differences in proximate and ultimate factors underlying each route to independent breeding highlight the need for simultaneous consideration when studying the evolution of delayed dispersal.

opencc-zeroDec 2015View details →

Data from: Male breeding experience, not mate familiarity, affects reproductive output in black brant geese

Individuals in species with long-term social monogamy often incur fitness costs after mate change. We evaluated the relative contributions of mate familiarity and male breeding experience to the costs of mate change of female black brant geese (Branta bernicla nigricans). We assessed the effects of mate change on relative nest initiation date, clutch size, brood size at hatch, growth rates of goslings, and prefledging survival of offspring. We modeled variation in relative nest initiation dates, clutch size, initial brood size, and gosling growth rates using generalized linear mixed models in Program R. We estimated prefledging survival with Cormack–Jolly–Seber models in Program MARK using reencounters of webtagged goslings. Mate change had a small effect on relative nest initiation date, clutch size, and initial brood size, but no effect on growth rates of brant goslings. Females breeding with an unfamiliar, but experienced male had goslings with higher prefledging survival rates (ϕ = 0.44±0.11 [95% confidence interval]) than those breeding with a familiar, experienced mate (ϕ = 0.30±0.04). However, females that changed mates and re-paired with an inexperienced male had goslings with substantially lower prefledging survival rates (ϕ = 0.20±0.04) than any other group of females. Our findings indicate that reproductive output by female brant is affected by male experience rather than mate familiarity. We believe that female brant typically benefit from mate retention because most will not acquire an experienced partner after mate change.

Data from: The role of visual cues in mother–pup reunions in a colonially breeding mammal

Parental care is an important factor influencing offspring survival and adult reproductive success in many vertebrates. Parent-offspring recognition ensures care is only directed to filial young, avoiding the costs of misallocated resource transfer. It is essential in colonial mammal species, such as otariids (fur seals and sea lions), in which repeated mother-offspring separations increase the risk of misdirecting maternal effort. Identification of otariid pups by mothers is known to be multimodal, yet the role of visual cues in this process remains uncertain. We used 3-dimensional visual models to investigate the importance of visual cues in maternal recognition of pups in Australian sea lions (Neophoca cinerea). We showed that the colour pattern of pup pelage in the absence of any other sensory cues served to attract the attention of females and prompt investigation. Furthermore, females were capable of accurately distinguishing between models imitating the age-class of their own pup and those resembling older or younger age-classes. Our results suggest that visual cues facilitate age-class discrimination of pups by females and so are likely to play an important role in mother-pup reunions and recognition in otariid species.