Variation in animal social interactions emerges from individual responses to social and physical environments and plays a key role in shaping pathogen transmission, gene flow and information transfer. Although hunting can induce changes in contact patterns through disruption of the social environment, the non‐consumptive effects of hunting have not received much attention compared to demographic effects of harvest. We examined the effects of hunting activities on contact rates in wild boar, a species particularly exposed to social disruptions owing to its high sociality and intense management. Using GPS‐telemetry data from 21 populations across Europe (435 unique dyads), we analysed how hunting activities impact social contacts within and between wild boar groups while accounting for confounders potentially shaping contact heterogeneity (e.g. habitat productivity, population density, predation, seasonality, individuals' sex and spatial proximity). We found that drive hunts, but not individual hunts, lowered contact rates within wild boar groups. Contact rates tended to be negatively related to drive hunts' frequency. We did not observe the effect of hunting mode on contact rates between members of different groups, which was mainly shaped by a positive relationship with spatial proximity. Contact probability among females from different groups was lower compared to male–male or mixed‐sex dyads. Synthesis and applications . Our study showcases how hunting disturbance influences social contact rates in a group‐living wild mammal. Along with other biotic and abiotic drivers, hunting modality plays a significant role in shaping intra‐group, but not inter‐group, contacts. Reduced group cohesion induced by drive hunts could negatively impact survival, foraging efficiency, and resource utilization. Hunting management could mitigate those negative impacts by spatially spreading driven areas throughout the season and targeting different groups each time. Our results suggest that hunting disturbances should not enhance disease spread through increased inter‐group contacts. Yet, hunting‐induced escape movements could still pose a risk of transmission into new areas. Inter‐group connectedness appeared to be maintained predominantly by males which could be targeted if disease transmission was a major management objective. Spatial proximity between individuals can be a reliable index of the amount of direct contacts within wild boar populations.

Diseases circulating at the wild-domestic animal interface are increasingly difficult to control due to human encroachment into wildlife habitats. Understanding the factors driving wild animals to visit livestock farms is crucial for reducing the risk of disease outbreaks with severe economic and social consequences. In this study, we quantified the contact rate at the wild boar-domestic pig interface across Europe using a large-scale dataset of wild boar GPS tracking and domestic pig farm geolocations. We estimated wild boar contact rate with pig farms at hourly and monthly scales and analysed the influence of environmental, wild boar- and farm-related variables. Across 187 tracked wild boars and 457 pig farms, we detected 3322 contact events, with a highly skewed contact distribution: only 5% of wild boars and 1% of farms accounted for 50% of all events. On average, each wild boar had 1.59 contacts per month with a given farm (95% CI: 1.33-1.85) and 2.58 contacts per month when considering all farms located within its monthly home range (95% CI: 1.62-3.53). Seasonal variation differed between sexes, with a bimodal distribution for males with contact rates peaking in March and August-September, and a slight increase in contact rate throughout winter for females. Monthly contact rate increased with forest cover, human footprint, wild boar population density and individual proximity to pig farms. Farms with more built infrastructure faced fewer contacts, and larger farms had higher contact rates. Contacts occurred mostly after sunset and around sunrise. Synthesis and applications. Our results highlight the need to incorporate wild boar spatio-temporal behaviour and farm context into strategies aimed at reducing contact at the wild-domestic pig interface. While physical barriers and avoiding unintentional feeding remain essential, targeted measures during high-risk periods, such as night-time surveillance in summer and autumn, especially around large farms in wooded landscapes or areas with high wild boar density, could help reduce contact occurrence.

In temperate Europe, forests faced climate change and at the same time an important increase of ungulates densities and sympatric context, inducing an alteration of vegetation. Ungulates usually showed diverse foraging behaviour permitting co-existence, but during shortage periods as winter, significant food competition may occur. However, hot periods can be also detrimental and are not very documented in temperate Europe. Furthermore, ungulates mostly relied on plants, but fungi may also complete the diet. In this study, we investigated the diet of three sympatric ungulates (red deer, roe deer and wild boar) during cool and hot periods using faecal eDNA metabarcoding to detect plant and fungi. We compared the diet composition and diversity of three sympatric forest ungulates and calculated diet overlap using pianka index. We observed a high overlap in the diet of roe and red deer in both periods, whereas diet overlap was lower for both deer with wild boar. Overlap tends to be higher during the hot period than cool. The composition of diet was different among ungulates, and the diet of roe deer less diverse than other ungulates. However, we did not detect any effect of the period on diet composition or diversity, but our study still represented one of the few that investigated such potential hot period resources shortage for ungulates. Nevertheless, the combined effect of increased ungulate densities and global change may be detrimental for forest stands regeneration if resources become scarce.

Urbanization is rapidly increasing, transforming ecosystems and favoring generalist species that adapt to human-modified environments. The wild boar, a highly adaptable species, is expanding its range and increasingly observed in urban and peri-urban areas, where it can cause accidents, damage, and health concerns. To mitigate their presence, non-lethal control strategies such as vegetation clearing in peri-urban parks and wastelands are being implemented to reduce the number of suitable resting sites. However, the ecological consequences of such habitat modifications on other wildlife species remain poorly understood. This knowledge gap limits the development of effective urban wild boar management strategies that seek to balance ecological, social and economic considerations without lethal control of wild boar populations. In this context, we used 48 camera-traps deployed over a year to study the covariation between wild boars and other mammal species in a peri-urban area, with the aim of guiding targeted and effective management strategies. Here, we show a widespread presence of wild boars but no spatial or temporal covariation between the wild boars and the other species. In contrast, we found strong spatial structuring but little temporal variation of the mammal community, confirming that spatial factors, rather than seasonal changes, largely shaped species distributions. The study of the temporal variation across months indicated minimal seasonal structuring but revealed substantial within-site variability in month-to-month species abundance, with a general abundance gradient driven by common species like wild boar, cat, and fox. In conclusion, our results show that the lack of spatial covariation between wild boar and other species prevents reliable predictions, supporting a targeted rather than general approach to vegetation management.

Natal dispersal is a key process in ecology and evolution. Similarities of dispersal patterns between relatives can lead to small-scale kin structure within populations with consequences for population dynamics and genetics. Most studies have focused on birds, lizards, and small mammals. How family effects may shape sex-specific natal dispersal patterns in a large-sized social mammal remains unexplored. We fill this gap thanks to a 30-year-long monitoring of a wild boar population. This polytocous, polygynous, and size dimorphic species displays a matrilineal social organization. From the monitoring of individuals from early life to adulthood, we characterized natal dispersal patterns by investigating the propensity to disperse and the dispersal distance. As expected for a species subjected to strong sexual selection, offspring males dispersed more often and farther than females. Looking specifically at similarities of dispersal patterns among relatives within a group, we found that offspring females from the same family displayed more similar dispersal propensity and distance than females from different groups, highlighting family effects. However, this dispersal pattern did not hold for males. Family effects can thus shape natal dispersal patterns in a sex-specific way in social mammals and are key to understanding individual variation in dispersal patterns.

Capture-recapture (CR) models have been used for decades to estimate population size and demographic rates in natural populations from the monitoring of individuals. One of the most frequent deviations from assumptions required in CR studies is the immediate trap-dependence that corresponds to the correlation between capture events. We review empirical evidence of immediate trap-dependence across vertebrate populations where several capture types exist, record possible variation in the occurrence and the sign of trap-dependence and discuss its biological meaning. We highlight that when trap-dependence occurs, trap-happiness, the higher probability for an individual to be captured again at i + 1 if captured at i, is the rule rather than the exception, whatever the type of capture. However, the occurrence of trap-dependence varies among populations of a given species and only displays a moderate repeatability in a given species. It also varies within a population depending on sex, age, or type of mark, and reflects among-individual variation in personality (bold versus shy), social status, or ecological context. We argue that immediate trap-dependence can be seen as a form of dynamic heterogeneity, reflecting clear among-individual differences. Although trap-dependence is generally considered simply as a noise to account for, it has a clear biological meaning in terms of among-individual differences.

For many animal species, resting and activity happen at distinct sites. As animals are limited in how far they can travel between resting and foraging sites, the spatial layout of those sites may constrain animal movements across the landscape. In anthropized landscapes, suitable resting sites are often scarce and dispersed, and movements between them are generally more constrained than in natural landscapes. In this context, animals may not be able to travel between any pair of resting sites in one single phase of activity. Thus, it is likely that in anthropized landscapes, some resting sites have a central position in the movement patterns of animals, serving as 'stepping-stones' allowing them to travel between different sectors of their home range. We tested this hypothesis by investigating the resting site selection and movement patterns of wild boars Sus scrofa along wide gradients of anthropization and forest cover across Europe. First, we characterized the dynamics of resting site utilization by the wild boar in response to anthropization, on a continental scale. Then, using network analysis applied to animal movements, and betweenness centrality as a metric, we investigated the relative contribution of resting and activity sites in connecting different parts of the home range. We found that the importance of resting sites in structuring movement patterns depended on the characteristics of the landscape, and notably on the level of anthropization. Our results suggest that in anthropized landscapes, where resting sites are sometimes a limiting resource for many animals, their spatial layout may play an often unnoticed yet important role in allowing animal movements across the landscape.

Wild boar (Sus scrofa) populations have been steadily increasing across Europe in the last decades, due to the synergy between landscape modifications, the ecological plasticity of the species and global warming. However, since 2014, an increasing number of these populations have also been affected by African swine fever (ASF) and have experienced increased mortality. Moreover, in 2020 and 2021, wild boar hunting regimes were temporarily changed due to restrictions in response to COVID-19. There is therefore a need for a pan-European assessment of the long-term trend in wild boar populations. We analysed wild boar hunting bags from 21 European countries, as a proxy of population abundance, to estimate long-term trends between 2000 and 2022. We also identified possible changes in harvests due to COVID-19. Finally, we summarized changes in the number of hunters between 2018 and 2023 in 19 European countries. Wild boar harvest has increased steadily over the last two decades, peaking at over 3.6 million harvested individuals in 2019. Since the appearance of ASF in Europe, hunting bags in most affected countries decreased, i.e. either immediately after the first outbreak or following a short-term increase of the harvest after the outbreak. Restrictions due to COVID-19 did not have any clear impact on the total number of harvested wild boar. Over the past six years, in spite of mixed trends between the countries, the overall number of hunters has decreased across Europe.

Host and pathogen dynamics are driven by seasonal variation, leading to complex epidemic patterns which are not well understood. Here, we linked demography and epidemiology in a single framework to reach a mechanistic understanding of disease dynamics in natural populations characterized by seasonality. We applied this approach to depict the interplay between a host, the wild boar, and a viral disease, African swine fever. This virus spreads in wild boar by direct-contact among living individuals or though contacts with infected carcasses. In this system, both host and pathogen show seasonal patterns: survival and reproduction probabilities vary across the year in the wild boar, and virus persistence in the environment is affected by temperature which influences the speed of carcasses degradation. Using a stochastic individual-based model, we showed that virus invasion success strongly varies according to the time of introduction due to the seasonal specific interaction between the virus and host. Furthermore, the shape of the following epidemic varies across seasons, with variation in speed and magnitude of the outbreak. Consequently, the host population response was also season-specific, both regarding the speed of the decline and the change in population structure. Overall, our study highlights the inextricable connections between host, pathogen and the environmental dynamics, and the importance to consider each component to understand disease dynamics.

Biased birth sex ratios have been documented in many mammalian populations, but it is often difficult to know whether they result from biases in the sex ratio at conception and/or sex differences in prenatal mortality. It is generally admitted that there is an excess of males at conception and a higher level of mortality during gestation for males because of a positive relationship between size and vulnerability. Here, we challenge this classical prediction in a wild boar (Sus scrofa) population facing highly variable food resources (mast seeding) and in which male fetuses are heavier than females. Using long-term hunting and mast seeding data, we show that sex ratio at conception is balanced and that females suffer from higher embryonic mortality particularly in large litters, whatever the level and the type of food resources. One possible explanation is that a female embryo is ready for implantation later than an identically aged male because of slower development and is more likely to miss the implantation window. To what extent a lower survival of female embryos is a common feature in mammals remains to be carefully explored.

1. African swine fever (ASF) poses a serious threat to domestic pigs and wild boar populations. Wild boar can disperse the virus, making effective containment crucial. One of the main control strategies involves establishing restricted zones around detected cases, i.e., areas with temporary restrictions on access and hunting; however, determining the appropriate size of these zones remains a major challenge. 2. To inform the size of restricted zones, we analyzed GPS data from 527 wild boar across 46 European study sites using a two-step approach combining first-passage time analysis and survival modelling to quantify the risk of wild boar leaving areas of different radii (i.e., spatial scales). We investigated how the risk of leaving varied over time and across environmental gradients. To go further, we used our model findings to develop an online application that generates predictive maps of optimal buffer sizes for ASF management at the European scale, based on a given risk threshold (the maximum acceptable probability that a wild boar leaves the area). 3. We found that the relationship between radius and the risk of leaving is negative exponential, and the risk of leaving increased over time, with a more rapid increase for smaller radii. Landscape homogeneity, terrain ruggedness and human impact increased the risk of leaving, with stronger effects at small scales. Contrary to other predictors, agricultural cover exerted a strong negative effect on movement over large spatial scales, especially when it was abundant. 4. Across Europe, a buffer radius of ~8 km is likely sufficient around high-risk infection zones in most areas (considering an infectious period of 14 days and a risk threshold of 5%); however, in certain areas, a radius of up to 20 km may be needed to effectively limit wild boar movement. 5. Synthesis and applications: Our results highlight the need for adaptive, context-specific restricted zones. Buffers of 8 km around ASF-affected areas can limit the risk of infected wild boar dispersal, but they may be reduced to 5 km in highly heterogeneous landscapes or high-human impacted areas. Larger buffers may be required in agricultural landscapes. We provide spatially explicit outputs (optimal buffer sizes) that can directly inform policy and wildlife disease response strategies. The approach can be adapted to any other infectious diseases. ### Competing Interest Statement The authors have declared no competing interest. Bavarian State Ministry of the Environment and Consumer Protection Bavarian Health and Food Safety Authority François Sommer foundation University of Montpellier, ANR-16IDEX-0006 BoundaryBoar project, ANR-22-CE03-0002 Spanish Ministry of Science, Innovation and Universities, CPP2023-010878 Thuringian Ministry of Environment, Energy and Nature Conservation Swedish Environmental Protection Agency, https://ror.org/02y7nf053 Marie-Claire Cronstedts Stiftelse, https://ror.org/018g1zw27 Önnesjös foundation

Commonly used two-sex discrete-time population projection models rely on mating functions developed for continuous-time frameworks that overestimate the number of unions between reproductive individuals. This has important consequences for our understanding of the evolution and demography of two-sex populations and consequently for management and conservation. Here, we propose a novel mating function that is robust by obeying all properties necessary to be ecologically valid and flexible by accommodating all mating systems and efficiency in mating encounters. We illustrate the usefulness of this novel function with an application to the sexually size-dimorphic and polygynous wild boar (Sus scrofa). We show that the population growth rate depends on the harem size, the operational sex ratio, and the mating efficiency. This novel function can be applied to all mating systems and tactics and is highly relevant in the context of global changes under which mating systems and mating efficiency are expected to change.

Temporal autocorrelation in environmental conditions influences population dynamics through its effects on vital rates. However, a comprehensive understanding of how and to what extent temporal autocorrelation shapes population dynamics is still lacking because most empirical studies have unrealistically assumed that environmental conditions are temporally independent. Mast seeding is a biological event characterized by highly fluctuating and synchronized seed production at the tree population scale as well as a marked negative temporal autocorrelation. In the current context of global change, mast seeding events are expected to become more frequent, leading to strengthened negative temporal autocorrelations and thereby amplified cyclicality in mast seeding dynamics. Theory predicts that population growth rates are maximized when the environmental cyclicality of consumer resources and their generation times are closely matched. To test this prediction, we took advantage of the long-term monitoring of a wild boar population, a widespread seed consumer species characterized by a short generation time (∼2 years). As expected, simulations indicated that its stochastic population growth rate increased as mast seeding dynamics became more negatively autocorrelated. Our findings demonstrate that accounting for temporal autocorrelations in environmental conditions relative to the generation time of the focal population is required, especially under conditions of global warming, where the cyclicality in resource dynamics is likely to change.

European wildlife has been subjected to intensifying levels of anthropogenic impact throughout the Holocene, yet the main genetic partitioning of many species is thought to still reflect the late-Pleistocene glacial refugia. We analyzed 26,342 nuclear SNPs of 464 wild boar ( Sus scrofa ) across the European continent to infer demographic history and reassess the genetic consequences of natural and anthropogenic forces. We found that population fragmentation, inbreeding and recent hybridization with domestic pigs have caused the spatial genetic structure to be heterogeneous at the local scale. Underlying local anthropogenic signatures, we found a deep genetic structure in the form of an arch-shaped cline extending from the Dinaric Alps, via Southeastern Europe and the Baltic states, to Western Europe and, finally, to the genetically diverged Iberian peninsula. These findings indicate that, despite considerable anthropogenic influence, the deeper, natural continental structure is still intact. Regarding the glacial refugia, our findings show a weaker signal than generally assumed, but are nevertheless suggestive of two main recolonization routes, with important roles for Southern France and the Balkans. Our results highlight the importance of applying genomic resources and framing genetic results within a species’ demographic history and geographic distribution for a better understanding of the complex mixture of underlying processes.

African Swine Fever (ASF) has been slowly but steadily increasing its endemic range throughout Europe, posing an imminent risk to the pig industry. ASF transmission among wild boar occurs mainly through wild boar population movements, hence wild boar presence and density are important risk factors for introducing, maintaining, and spreading the disease. The understanding of wild boar population dynamics and their role in ASF transmission and persistence remains limited. It is crucial to gain knowledge in this area to improve wildlife management while minimizing the risks for ASF introduction and spread. We adapted an individual-based spatio-temporal stochastic model developed by Halasa et al. (2019) and tailored it to two regions in France. The model assessed yearly hunting activity, the carcass persistence seasonality, and the specific landscape characteristics of the Franco-Belgian border region and the Pyrénées-Atlantiques department. Following the establishment of local population dynamics through preliminary runs of the model, the model was run 100 iterations over 8 years in the two study areas where ASF was randomly seeded after the 2nd year of simulation. For each scenario, the model was initiated with 500 wild boar groups randomly spread across the study areas. Hunting activities were included and excluded to assess the impact on population growth and ASF spread. Results showed an ever-growing wild boar population for all scenarios, which was balanced when hunting activities were included. When introducing ASF, the wild boar populations were dramatically impacted in both areas with a decrease of 63 % of the population at the Franco-Belgian border and 86 % in the Pyrénées-Atlantiques department. Habitat fragmentation and landscape connectivity were highlighted as important factors shaping ASF propagation. The Franco-Belgian border, which had the most fragmented habitat with unsuitable areas for wild boars, was shown to limit wild boar movements, reducing the probability, and spread of ASF across the landscape. The lack of connectivity was reflected in a less effective transmission and lower number of infected groups (406 versus 467). In contrast, the epidemic duration was lengthened in the fragmented habitat compared to the homogenous area (2.6 years vs 1.6 years). This study provided information on defining and implementing control measures in case of an ASF incursion, since delimitation of the area via fences artificially induces landscape fragmentation, which is important for controlling ASF outbreaks.

In seasonal environments, the timing of reproduction often matches with the peak of food resources. One well-known effect of global warming is an earlier phenology of resources, leading to a possible mismatch between the timing of reproduction for consumers and food peak. However, global warming may also change the dynamics of food resources, such as the intensity and frequency of pulsed mast seeding. How quantitative changes in mast seeding influence the timing of reproduction of seed consumers remains unexplored. Here, we assess how yearly variation in mast seeding influences mating time in wild boar (Sus scrofa), a widespread seed consumer species. We took advantage of the intensive monitoring of both female reproduction (1636 females) and acorn production over 6 consecutive years across 15 populations of wild boar in the wild. We found that mating time occurs earlier when acorn production increases in most but not all populations. In two out of 15 populations, heavy females mated earlier than light ones. Our findings demonstrate that mast seeding advances the mating time in some populations, which could perhaps impact how boars respond to climate change.

Intraspecific variations in mating systems have been reported in numerous species, especially when they live in varying ecological contexts. This leads to variability between populations with regard to the proportion of females engaging in multiple male mating, which depends on the number of males available. For hunted ungulate species, hunting is known to influence population structure, especially when males are preferentially targeted for trophy hunting. Here, we investigated how variations in hunting pressure and the yearly proportion of heavy males removed have impacted multiple paternity rates in five wild boar ( Sus scrofa scrofa ) populations located in similar ecological contexts. We found high rates of multiple paternity in all studied populations, confirming the recently reported promiscuous mating system of wild boar. However, variations in hunting pressure and removal of heavy males did not significantly influence multiple paternity rates, contrary to our expectation. Nonetheless, a slight tendency for a decreasing multiple paternity rate with increasing hunting pressure and for increasing multiple paternity rate with increasing removal of heavy males from the population was detected. Based on these results, we discuss an alternative hypothesis on the ecological processes sustaining the influence of hunting regimes on the mating system. Overall, hunting pressure and management rules might be sufficient to disrupt the mating system in any of the populations, so it is important to continue the sampling of wild boar populations at the European scale, especially in populations with little hunting pressure.

Abstract Mast seeding is a well‐known example of pulsed resources in terrestrial ecosystems. Despite the large literature available so far on the effects of mast seeding on the dynamics of seed consumer populations, it remains unknown whether heterogeneity in demographic responses to mast seeding exists both within a population of consumers and among consumer populations. Here, we fill this knowledge gap by assessing the effects of acorn production (i.e., oak mast) on all stage‐specific demographic rates (i.e., survival, growth, reproduction) in several consumer populations. From long‐term capture–mark–recapture data collected in three wild boar populations in Europe and detailed information on annual acorn production, we quantified the effects of acorn production on body mass‐specific demographic rates in these populations. We then built a body mass‐structured population model for each population and assessed the effect of acorn production on generation time—the mean age of mother at childbirth—and population growth rate using a combination of prospective and retrospective demographic analyses. Within populations, acorn production had a positive effect on reproduction (proportion of breeding females) and growth of small‐sized females. Survival remained buffered against environmental variation, in accordance with the demographic buffering hypothesis. Thus, all stage‐specific demographic rates were not influenced in the same way by acorn production. In turn, higher reproduction and growth probabilities involved higher population growth rates and shorter generation times. Despite these common demographic responses to mast seeding among populations, we highlighted marked among‐population variation in the magnitude of these responses. Also, while populations inhabiting resource‐rich environments took advantage of current acorn conditions, populations under resource‐poor environments stored and allocated acorns produced the preceding year to reproduction indicating contrasting breeding tactics along the capital–income continuum. Our results suggest heterogeneity in demographic responses to mast seeding, within and among populations. This is an important finding for our understanding of the effects of mast seeding on the dynamics of seed consumer populations.

Despite their importance in shaping life history tactics and population dynamics, individual growth trajectories have only been rarely explored in the wild because their analysis requires multiple measurements of individuals throughout their lifetime and some knowledge of age, a key timer of body growth. The availability of long-term longitudinal studies of two wild boar populations subjected to contrasting environments (rich vs. poor) provided an opportunity to analyze individual growth trajectories. We quantified wild boar growth trajectories at both the population and the individual levels using standard growth models (i.e., Gompertz, logistic, and monomolecular models) that encompass the expected range of growth shapes in determinate growers. Wild boar is a rather altricial species, with a polygynous mating system and is strongly sexually dimorphic in size. According to current theories of life history evolution, we thus expect wild boar to display a sex-specific Gompertz type growth trajectory and lower sexual size dimorphism in the poorer environment. While wild boar displayed the expected Gompertz type trajectory in the rich site at the population level, we found some evidence for potential differences in growth shapes between populations and individuals. Asymptotic body mass, growth rate and timing of maximum growth rate differed as well, which indicates a high flexibility of growth in wild boar. We also found a cohort effect on asymptotic body mass, which suggests that environmental conditions early in life shape body mass at adulthood in this species. Our findings demonstrate that body growth trajectories in wild boar are highly diverse in relation to differences of environmental context, sex and year of birth. Whether the intermediate ranking of wild boar along the precocial-altricial continuum of development at birth may explain the ability of this species to exhibit this high diversity of growth patterns remains to be investigated.

Many animal populations are subject to hunting or fishing in the wild. Detailed knowledge of demographic parameters (e.g. survival, reproduction) and temporal dynamics of such populations is crucial for sustainable management. Despite their relevance for management decisions, structure and size of exploited populations are often not known, and data limited. Recently, joint analysis of different types of demographic data, such as population counts, reproductive data and capture–mark–recapture data, within integrated population models (IPMs) has gained much popularity as it may allow estimating population size and structure, as well as key demographic rates, while fully accounting for uncertainty. IPMs built so far for exploited populations have typically been built as age‐structured population models. However, the age of harvested individuals is usually difficult and/or costly to assess and therefore often not available. Here, we introduce an IPM structured by body size classes, which allows making efficient use of data commonly available in exploited populations for which accurate information on age is often missing. The model jointly analyzes size‐at‐harvest data, capture–mark–recapture–recovery data and reproduction data from necropsies, and we illustrate its applicability in a case study involving heavily hunted wild boar. This species has increased in abundance over the last decades despite intense harvest, and the IPM analysis provides insights into the roles of natural mortality, body growth, maturation schedules and reproductive output in compensating for the loss of individuals to hunting. Early maturation and high reproductive output contributed to wild boar population persistence despite a strong hunting pressure. We thus demonstrate the potential of size‐class‐structured IPMs as tools to investigate the dynamics of exploited populations with limited information on age, and highlight both the applicability of this framework to other species and its potential for follow‐up analyses highly relevant to management.