Peer Community Journal

The recent large-scale circulation of High Pathogenicity Avian Influenza (HP AI) viruses H5Nx of clade 2.3.4.4b has been responsible for massive die-offs in wild species, notably in long-lived seabirds, with unknown implications for the immunity of surviving individuals. In the North Atlantic, northern gannet colonies were heavily affected in 2022, with more than 40% mortality observed among breeding adults and some surviving individuals developing dark irises. Using samples collected in 2023 and 2024 on Rouzic colony (France), we report persistent individual anti-AI antibody levels and seroneutralisation titres, with most of the immune individuals showing dark irises. A modelling approach further stressed the importance of long-lasting immunity in such species by showing that the proportion of individuals which kept their immunity between years strongly limited decreases in population size in case of repeated outbreaks. Overall, our results highlight the existence and importance of long-lasting immunity in long-lived species for population persistence.

Hunt s ancestor-descendant parameterization for fitting of evolutionary models to empirical paleontological sequences assumes independent log-likelihoods for the transitions between populations (Hunt, 2006). This is not quite correct, as he also pointed out in his paper. The reason is that adjacent trait differences share a trait mean value and its sampling error, and ignorance of this fact may give large errors in the estimated step size. Here, the problem is solved by use of the N-1 dimensional normal density for a random vector, where N is the number of samples. This results in a tridiagonal covariance matrix instead of Hunt s diagonal matrix, and the estimated step sizes, and thus prediction slopes, in cases where the estimated step variance is zero will then be identical to those found by weighted least squares estimation.

Reliable population estimates are essential for wildlife management, yet monitoring schemes often do not match the administrative scale at which decisions are made. We illustrate this challenge using the Eurasian lynx in the canton of Valais, Switzerland, where official state monitoring is fragmented across three reference areas surveyed in different years. We analyzed three winters (2023-2026) of independent, canton-wide camera trap data, recording 899 independent lynx captures (27, 31 and 34 adults per winter). Lynx distribution and reproduction concentrated in the Northwest and connected to the thriving Pre-alpine populations. Density modelling for 2025/2026 estimated 37 independent lynx (95% CI: 26-52) on the whole cantonal territory, corresponding to a density of 1.09 (0.77-1.56) individuals per 100 km2. These estimates are substantially below the figures improperly extrapolated from a cross-cantonal reference area and conveyed by political authorities. Future lynx management decisions should be rooted in scientifically sound, scale-relevant information.

The ectoparasitic mite Varroa destructor is the principal threat to managed honey bees, and a test case for the genome-scale methods applied to non-model organisms, nearly all of which infer from orthology. We reconstructed the first genome-wide protein-interaction network for V. destructor (7,080 proteins, 335,914 interactions), whose modular structure exceeds a degree-preserving null by 368 standard deviations, but whose every edge is interolog-transferred and every node conserved at least to Eukaryota. None of the 791 genes lacking an orthologous group enters it - arithmetic rather than discovery - yet the excluded compartment is large and coherent. It comprises 3,161 genes (30.9% of the proteome), shorter and less annotated than the rest; an annotation-free genome search detects orphans in a tick genome at 4.0% against 70.4% for networked genes. Within the orthology-bearing compartment visibility is non monotonic: the Acari-level bin (74.1%) falls below the Arthropoda-level bin (89.9%). The same logic applied to host comparison yields a benchmarked error: of genes called absent from Apis on group identity alone, 67.4% recover a sequence homologue - against zero for a shuffled null and 1.3% in the presence direction - rising to 78.3% in the least panel-biased stratum. Both figures are properties of the calling rule: under an identity floor the error directions cross near 34% identity; orthology cannot be said to err in either direction without fixing the criterion first. Host divergence resolves into gene absence and residue level substitution, falling in those two compartments respectively. A bee-sparing target map follows as broader impact.

The ocean tides influence key Earth system processes at a range of spatial and temporal scales. It is known that the geometry of ocean basins is the leading controller of tidal energetics, so well-constrained palaeogeographic reconstructions and tidal properties for Earths past are imperative when investigating other Earth system processes. Here, we present a novel way to constrain both deep-time tidal model results and reconstructions, by combining palaeoecology with sedimentology. We compare new palaeo-tidal model simulations for the Cambrian period, significant for the early origin and radiation of major animal fauna, to tidal proxies. One of the most abundant soft-bodied organisms preserved during this time are cnidarian medusae (jellyfish). A total of 17 cnidarian medusae localities were obtained through the literature, which had an adequate global distribution and occurred at regular intervals throughout the period of study. In some locations there were also estimates of palaeo-tidal range. Our results show a good agreement between the simulations and proxy data. In the few locations where there is disagreement, it is proposed that the palaeogeographic reconstructions are missing details, e.g., island chains, and our results allow for the palaeogeographic reconstructions to be improved. The proxy method presented is promising and can be applied to other time-periods with different marine fossils, particularly at evolutionary and extinction periods where the marginal marine environment is of importance.

The convergent lady beetle Hippodamia convergens is widespread in the Americas and considered an important beneficial insect due to its use in pest control. Early work on this species characterized the beetles as freeze-avoidant (freeze-intolerant), suggesting they survive low winter temperatures by physiologically preventing ice formation to temperatures as low as -15{degrees}C. Here, we show that H. convergens can be freeze-tolerant if ice formation occurs at relatively high temperatures. There was 100% survival following inoculative freezing at -0.5{degrees}C and exposure to -3{degrees}C for 20 hours, as well as freezing that spontaneously occurred in fed beetles exposed to -4{degrees}C for 4 hours. Males exposed to 0{degrees}C or -4{degrees}C for 4 hours had similar mating behaviours (latency to first mating, copulation duration) as control beetles exposed to 4{degrees}C, although sample sizes were too small to determine whether freezing itself had an effect on these behaviours. Several putative cryoprotectants were detected in fat body tissue of H. convergens: glycerol, proline, trehalose, and myo-inositol - in order of abundance. Exposure to -3{degrees}C for 20 hours, whether frozen or unfrozen, did not statistically affect cryoprotectant accumulation, although there was a trend towards increased glycerol following freezing. This study is the first to describe inoculative freeze tolerance in a lady beetle and establishes a baseline for future studies that examine the mechanisms underlying this freeze tolerance and the effects of freezing on reproductive behaviour. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=69 SRC="FIGDIR/small/744689v1_ufig1.gif" ALT="Figure 1"> View larger version (16K): org.highwire.dtl.DTLVardef@1c0382org.highwire.dtl.DTLVardef@12a5932org.highwire.dtl.DTLVardef@145f4adorg.highwire.dtl.DTLVardef@1c2cb22_HPS_FORMAT_FIGEXP M_FIG C_FIG O_LIHippodamia convergens can tolerate freezing at high subzero temperatures C_LIO_LIMating behaviour of males is normal after chilling or freezing C_LIO_LICryoprotectant accumulation may support overwintering survival C_LI

The vast majority of birds are diurnal and concentrate their vocal activity during daylight hours. However, some diurnal birds can also be vocally active at night, although the functions of this phenomenon remain poorly understood. We conducted playback experiments in the Warta Landscape Park (central Poland) to determine whether nocturnal singing by diurnal birds serves breeding-related functions by analysing responses to playback of songs from unfamiliar conspecific males. The sedge warbler (Acrocephalus schoenobaenus) was selected as the focal species because it exhibits relatively high levels of nocturnal song activity, while nine additional diurnal species detected near focal sedge warbler territories were included to explore whether responsiveness to nocturnal conspecific song extended across a broader taxonomic range. Playback experiments were conducted during the early and late stages of the breeding season and during the early and late parts of the nautical night. Out of 10 species tested, three responded vocally: sedge warbler, Savi s warbler (Locustella luscinioides), and common snipe (Gallinago gallinago). Sedge warblers did not modify song rate and song duration but increased flight activity after nocturnal playback. Savi s warblers and common snipes produced more vocalisations after playback than before in May, a pattern consistent with territorial defence function. General nocturnal vocal activity was higher at the beginning of the season, suggesting that birds motivation to establish territories and form pairs can extend into the night, providing additional benefits. Moreover, the probability of singing by the sedge warbler was higher in the latter part of the night. Our study demonstrates that nocturnal stimulation of foreign male playback of diurnal birds can elicit vocal responses from conspecifics, suggesting that nocturnal singing can occur in the absence of obvious artificial light pollution, but in the case of some species and environmental conditions, it may contribute to nocturnal social communication, especially in the early breeding season.

EU has reclassified the sika deer (Cervus nippon) as an undesirable invasive species based on reports that hybridization with the indigenous red deer (C. elaphus) may produce fertile offspring. Since sika-derived DNA previosuly introduced into the red deer population (introgression) cannot be removed, the crucial question is whether new (F1) hybridisation occur. To address this, we analysed the chromosomes in 56 sika and 22 red deer. All red deer had a chromosome number 2n=68. In contrast, the chromosome number in sika ranged from 64 to 67, due to the variable presence of two sika-specific Robertsonian translocations (ROB1,ROB2). In the free-ranging sika population in Jutland, >90% of the sika deer were homozygote for at least one of these ROBs, excluding that they could be F1-hybrids. Moreover, ROB2 was in Hardy-Weinberg equilibrium, further supporting the absence of gene flow between the two species. In contrast, ROB1 was in Hardy-Weinberg disequilibrium, suggesting negative fitness of heterozygotes, including potential F1-hybrids. In Jaegersborg Deer Park, the eight examined sika deer had the same genotype (absence of ROB1, homozygosity of ROB2), supporting that it is a founder population which may have been isolated for [~]100 years. Again, none of these can be F1-hybrids due to the homozygosity of ROB2. We conclude that F1-hybridisation between sika and red deer either does not occur or occur very rarely in Denmark. The study establish the Danish sika-populations as unique models for adressing important biological questions: What underlies the absence of hybridisation? Why are ROBs frequent in sika deer but not in the closely related red deer? How fast do new species/subspecies develop in isolated founder populations? Which factors determine, that some ROBs have little heterozygous effects, whereas others are selected against, with implications for the role of ROBs as genetic barriers promoting speciation, and for fertility problems in some human ROB carriers.

Network centrality is the workhorse of gene prioritisation, yet what a ranking omits is rarely audited. Scoring each selection against an annotation-count-matched maximum-entropy reference--asking whether a selected gene set covers the genomes functional space or collapses it-reveals that the criterion in standard use has a measurable blind spot in exactly the class it is meant to surface. Degree, the most widely used criterion, returns the cross-module bridges that are also locally dominant--connector hubs--and omits the non-hub connectors: where 26% of the genome occupies these coordinating roles, a degree-ranked list holds 18% and an EDVS-ranked list 55%, and degrees top-1% collapses functional coverage below the reference on all five networks tested. We repurpose EDVS (Entropy of Degree-Vector Sums), an information-theoretic diversity measure, as an annotation-free, partition-free centrality that recovers this omitted class. The coverage it preserves is carried by cross-module participation P, which cannot be computed without a community partition; EDVS matches P-level coverage on all five networks using none, and retains 0.84 of its selection under edge perturbation that leaves partition-based selections at 0.21-0.46. The deficit is general: the collapse holds in the same direction on the two networks built without functional annotation (0.5-1.1 bit; co-expression, physical interaction) as on the three supervised by it (1.6-3.3 bit; RiceNet, AraNet, STRING), so supervision amplifies it rather than creates it. The remedy is bounded: EDVS ceases to preserve coverage on the sparse physical-interaction network. And the class EDVS isolates is organizational, not an importance signal: pre-registered probes--essentiality, transcription-factor identity, tissue-specificity, date/party-hub character, phenotype co-localisation--return null or reversed throughout. The conclusive ones are equivalent to their degree-matched nulls within {+/-}5 percentage points (demonstrated, not merely undetected), and the classical coupling of centrality to importance itself holds only network-dependently. Author SummaryGenes rarely act alone: many diseases and agricultural traits are shaped by genes that coordinate several biological processes rather than specialising in one. The standard way to find such genes in a network of gene interactions is to count each genes connections--its "centrality"--and rank genes by that count. We show this standard approach has a blind spot: it favours genes that dominate one process over genes that quietly bridge several processes without dominating any, and this blind spot appears across rice, thale cress, and yeast gene networks. We repurpose a diversity measure from an unrelated field (originally used to compare citation patterns) as a new way to rank genes that finds these bridging genes from network structure alone, without needing gene-function annotations--which are themselves incomplete and biased toward well-studied genes--or a prior, unstable step of splitting the network into modules. We are careful to show where the new approach also falls short: on sparse, noisy networks it stops working, and the genes it recovers are not shown to be more biologically important than other genes, only differently positioned. What that position is for is a question this work leaves open.

Among Madagascar primates, the sportive lemurs (family Lepilemuridae) have seen their species diversity increase from eight in 2005 to 26 in 2009 mostly by applying the phylogenetic species concept to DNA barcode data. Despite the genus being speciose, only one case of sympatry is known from northern Madagascar, where two sportive lemur species described based on low mtDNA divergence, Lepilemur ankaranensis and Lepilemur milanoii, were found to co-occur at the center of their joint distribution range. Here, to clarify the taxonomy of these two species and examine their sympatry, we apply an integrative taxonomic framework to genomic and morphological data from 84 individuals of L. ankaranensis and L. milanoii, encompassing their entire distribution range and the forest of Analafiana, beyond their southernmost limit. Using clustering, multivariate, and isolation by distance analyses, we find no evidence of a sympatric zone and show that despite clear genetic differentiation between regions, the genomic and morphological diversity of the L. ankaranensis, L. milanoii-Analafiana group is clinal and explained by geographic distance. These results clarify that L. milanoii is a junior synonym of L. ankaranensis and that the Analafiana forest population belongs to L. ankaranensis, extending its distribution. It further implies that the 'sympatric' zone, the Andrafiamena forest, hosts conspecific individuals with slightly differentiated mtDNA backgrounds, rather than slightly differentiated sympatric species. Lastly, we re-evaluate the IUCN conservation metrics of L. ankaranensis, which continue to qualify as Endangered (EN) under the B1ab(i-v) criteria.

Global Biodiversity Information Facility (GBIF) occurrence retrievals for an irregularly shaped region are limited by the API spatial query capabilities - rectangular envelopes or size/vertex-limited WKT polygons - neither of which conform to protected areas, sacred groves, wetlands, panchayat or municipal boundaries or any other arbitrary KML polygon of interest queried by users. This paper presents and validates an open, self-contained, adaptive spatial-tiling protocol that (i) ingests any KML polygon of any shape, size and location on earth, breaks it into a set of GBIF API-compatible rectangular tiles, (ii) queries, cleans and clips the individual records to the target polygon, and (iii) summarises the inventory with a generic diversity-completeness-rarefaction module, with minimal manual re-parameterisation between sites. The protocol implements an iterative quadtree refinement algorithm that adapts tile number, size and location to the target polygon geometry, is combined with a fault-tolerant pagination/retry query system, a boundary-exact two-step clipping procedure and a Chao1-based completeness assessment to ensure statistical comparability between sites of different spatial extent and sampling intensity. The algorithm is implemented in open R source (sf, terra, rgbif, tidyverse) with the tiling algorithm controlled by the four parameters only (initial cell size, area floor, tile overlap threshold, recursion limit), with default settings on a new site by simply changing the input file path. This paper describes in detail its five main components - (i) polygon input and validation, (ii) quadtree adaptive tiling, (iii) polygon coverage verification, (iv) tile-wise GBIF query with retry/shrink pagination and partial data retention, (v) boundary-exact deduplication, clipping and diversity estimation. A downstream generic module estimates diversity, Chao1 richness/completeness and Hurlbert rarefaction, for each taxonomic rank and generates rank-ordered diversity tables as output. The generalisability of algorithm to multiple sites has been demonstrated with second polygon (Sonamukhi Sal forest dominated stretch, Bankura district, West Bengal; approx. 610 sq km) that differs from the first (Bishnupur Sal forest dominated stretch; 938 sq km) in both size and complexity (10 vs 34 KML vertices) and report the tiling and diversity metrics comparable results across the two polygons. With no parameter changes, the algorithm generated 135 adaptive query tiles for Sal forest dominated stretch adjoining Bishnupur, and 86 tiles for Sal forest dominated stretch Sonamukhi SDFP, covering completely the area of both polygons. The number of tiles per 100 sq km is comparable between the two runs (14.4 vs 14.1 tiles) despite the 35% difference in polygon size and 3.4x vertex count. The tile-wise querying with retry/shrink pagination retrieved 6,169 GBIF records (excluding errors) with boundary-exact clipping across 404 species for Bishnupur and 1,222 GBIF records (excluding errors) across 271 species for Sonamukhi; the generic diversity module processed the records without further parameter changes and generated comparable metrics for each rank at both sites. The protocol addresses a general bioinformatic challenge in polygon-based GBIF queries, is provided as an open, reusable, documented method which has been validated on two sites. Because the protocol has so far been validated on only two polygons that differ markedly in size, shape and observer regime, it may be regarded as an initial cross-site validation rather than a comprehensive benchmark, and recommend testing on a broader, globally distributed set of polygons before the approach is treated as a general-purpose standard.

Barley (Hordeum vulgare) is a key cereal crop with exceptional adaptation to diverse environments. With a large, highly repetitive diploid genome, barley presents challenges for pangenome representation. Starting from the reference genome MorexV3, we describe the construction of a barley graph (Pan20) representing the global diversity of landraces and cultivars captured in the public pangenome V1. For mapping arbitrary sequences, a greedy strategy is proposed that combines GMAP alignment followed by intersection with a Practical Haplotype Graph (PHG). This enables presence-absence variation detection and provides a consistent MorexV3 physical coordinate system across genotypes, enabling comparative analysis and visualization. For imputation of genomic data, the PHG approach relies on k-mer pseudo-alignment against the graph. Benchmarks show that Pan20 can accurately align barley genomic and transcriptomic sequences, including those not present in the Morex reference, revealing that a third of long genomic sequences map on non-reference genomes. Moreover, experiments with Genotyping by Sequencing and low-pass sequencing data indicate that FASTQ files can be efficiently mapped and imputed against the graph, preserving local haplotype context. This flexible and scalable graph framework allows barley researchers to explore genetic diversity beyond a single reference and facilitates analysis of diversity panels at the haplotype level, going beyond SNPs. Documentation and a Docker container are available at https://github.com/eead-csic-compbio/barleygraph. The graph sequence mapping utility was added to the Web application https://barleymap.eead.csic.es.

Dense semilandmarks describe 3D surfaces with hundreds to thousands of points, and sliding them by bending energy or Procrustes distance is a near-universal default. Three questions remain open: does dense sampling add shape beyond fixed landmarks, how many points are needed, and does sliding help or harm? Real specimens cannot answer them: the true correspondence is unknown. We tested two workflows, ALPACA (single-template registration) and DeCAL (landmark-anchored correspondence), on 496 mouse skulls at 250-1,000 points, with and without sliding, scored by surface reconstruction. We repeated it on 500 synthetic skulls with exact correspondence, measuring each point's distance to its true homologue. Dense semilandmarks lowered error for almost every specimen; the fixed landmarks added little but supplied anchoring the semilandmarks could not, and the anchored method was more accurate. The benefit saturated near 250 points for ALPACA but kept improving to 1,000 for DeCAL. Procrustes-distance sliding harmed every configuration; bending-energy sliding helped only a poor, landmark-free correspondence, vanishing once anatomical anchors spanned the form. Match the sliding decision to the correspondence in hand: relax a poor one, leave a good one alone, never slide toward the mean. Known-correspondence specimens offer a general test of landmarking and sliding against ground truth.

Cultivar susceptibility strongly influences the epidemiology of vector-borne plant diseases, and understanding cultivar-specific variation can inform management strategies. This is particularly relevant for flavescence doree, an incurable grapevine disease associated with a phytoplasma and transmitted by the leafhopper Scaphoideus titanus. In this study, we investigated the susceptibility of the main Swiss varieties, by combining controlled insect-mediated inoculation experiments with complementary field analyses conducted at progressively finer spatial scales. Together, these approaches allowed us to compare both infection probability and phytoplasma relative titre under standardised transmission conditions with disease incidence and relative titre under natural epidemiological conditions. For most cultivars, laboratory results were broadly consistent with field observations. However, a marked discrepancy emerged in the relative infection pattern between the two main grapevine cultivars grown in Switzerland: Chasselas and Pinot Noir. Under controlled conditions, they did not differ significantly in either their probability of infection or the phytoplasma relative titre, indicating no detectable difference in susceptibility to phytoplasma infection. In contrast, Pinot Noir consistently showed higher disease incidence than Chasselas under natural conditions. This pattern was observed across all spatial scales examined, from regional surveys to neighbouring vineyard plots, and was mirrored by higher phytoplasma relative titres. Importantly, under controlled conditions, S. titanus mortality during the one-week inoculation period was significantly higher on Chasselas than on Pinot Noir, indicating that Chasselas may provide a less favourable host for S. titanus. Together, these findings support the hypothesis that differences in field disease incidence between these cultivars may arise from differences in vector performance rather than intrinsic susceptibility to phytoplasma infection. This highlights the importance of considering plant-vector interactions, alongside susceptibility to infection, when assessing cultivar-specific vulnerability to vector-borne plant diseases.

The performance of any natural population in variable environments depends on contemporaneous changes in its vital rates (e.g., survival, reproduction) as well as legacies carried by its population structure. Yet whether the relative contribution of these two pathways can be predicted from life history remains unknown. Here, we use stochastic simulations of 1,986 matrix population models from 137 species to quantify the contribution of transient dynamics to variation in population growth rate, and test its associations with key life history traits. Longer generation times were associated with reductions in transient contributions, contrary to theoretical expectations. Greater stage-specific survival heterogeneities were associated with increases in transient contributions, whereas greater iteroparity was associated with decreases in plants but increases in animals. These associations were robust to body size, phylogenetic relationships, and vital-rate variability. Life history traits therefore provide a strong predictor for when population structure shapes population responses to environmental variability.

Originating at the base of the bilaterian tree of life, the monoaminergic (MOA) system is a pivotal and evolutionarily conserved regulator of animal development and of responses to changing environmental conditions. Investigating the ontogeny of monoaminergic modulation in model systems such as marine bivalve molluscs is therefore particularly relevant, as their life cycle and developmental transitions are strongly influenced by environmental cues. Here, we characterized the spatio-temporal and tissue-specific expression of components of the MOA system during early larval development of the Mediterranean mussel Mytilus galloprovincialis using both time resolved transcriptomics and in situ Hybridization Chain Reaction (HCR). Our results identify serotonin and dopamine as the predominant and interconnected monoaminergic pathways deployed during early mussel development, with receptors, enzymes, and selective transporters broadly expressed across both neuronal and non-neuronal tissues. Notably, the expression of receptors preceding that of the corresponding biosynthetic enzymes indicates early, non-neuronal roles of monoaminergic signalling, supported by their localization in peripheral tissues such as ciliated epithelia. Altogether, These findings support the hypothesis that the MOA system acts as a pervasive and tightly regulated modulator of larval morphogenesis and could therefore play an evolutionary conserved role in mediating development and environmental plasticity in developing bilaterian organisms.

The impact of invasive species on marine ecosystems is rapidly increasing, where they often outcompete native species in the absence of natural enemies. The parasite release hypothesis states that the success of invasive species relates partly to the loss of natural parasites during introduction and lower susceptibility to native parasites. Barnacles are highly successful invaders due to broad environmental tolerance and dispersal via shipping, but whether parasite release also participates in this success remains unknown. In this study, we analyse parasite infection patterns in native and invasive barnacles in the Wadden Sea by surveying communities across tidal zones. Additionally, year-round molecular monitoring of larval stages and a literature review were used to track the distribution of the invasive Pacific barnacle Balanus glandula in Europe and document its appearance in the Wadden Sea. The long-established invasive Austrominius modestus dominated the high and middle intertidal zone, whereas native species (Balanus crenatus and Amphibalanus improvisus) prevailed in lower zones. Native and invasive barnacles differed in parasite infection frequency (mostly cestodes and trematodes). The native Semibalanus balanoides had the highest prevalence (27%), followed by the invasive A. modestus (11%), and no infections were found in B. glandula. Lower parasite prevalence in invasive barnacles is consistent with the hypothesis that parasite release supports invasion success. In the absence of competent parasites, B. glandula could impact native barnacles through competition. Continued monitoring of B. glandula is recommended to track its distribution, interactions with native species, and parasite acquisition, providing further insight into the parasite release hypothesis.

Managers must make decisions in the face of uncertainty, especially when available resources are limiting. Identifying thresholds when certain conditions are met or exceeded enable the potential to mitigate risks. In 2005, sustainable harvest levels of willow ptarmigan were identified to avoid harvest efforts exceeding three hunter days km2. Here we evaluate these recommendations by analyzing line transect counts and harvest data from six areas forming three open/closed pairs in a region of state managed willow ptarmigan harvest. We developed three sets of Bayesian hierarchical models, one static distance model, and two dynamics models. One mechanistic hazard model and a Gompertz phenomenological model. Adult and juvenile density showed pronounced year-to-year variation that was largely synchronous across all six sites regardless of hunting status. The harvest effort parameter shows a striking difference between the two models. In the Hazard model, is positive, and excludes zero with near certainty, but in the Gompertz model, the parameter is highly uncertain. However, the two models do not contradict each other but answer complementary questions with different sensitivity to the harvest signal, harvest mortality is additive at the individual level, but this additive mortality is masked at the level of population abundance. The demographic cost of harvest is therefore real and quantifiable through the survival chain, but bounded in the long run by the stabilizing dynamics. A fixed limit anchored to monitored effort and bag is not a crude substitute for adaptive management but the appropriate design under the information commonly at hand. It will be a precautionary instrument grounded in the one relationship this study establishes firmly, the translation of hunter effort into harvest mortality.

1. Natal dispersal is a key process in population ecology because it links local demographic processes to broader-scale population dynamics by redistributing individuals. When using capture-recapture data, multistate capture-recapture models using discrete spatial units as states are the gold standard for estimating natal dispersal among spatial units while accounting for spatial variation in survival, recruitment and imperfect detection. However, because their computational cost increases rapidly with the number of spatial units, applications have been limited to a small number of units. Therefore, in practice, these models cannot provide spatially detailed inference on natal dispersal across large landscapes. 2. We develop a computationally efficient Bayesian capture-recapture model, called the efficient natal dispersal (END) model, to estimate natal dispersal among discrete spatial units jointly with spatial variation in demographic parameters and detection probabilities. The END model relies on two key structural features: juveniles and breeders are separated into two arrays, and resightings outside the natal spatial unit are aggregated over time for individuals released as juveniles. 3. Using simulations, we show that the END model is considerably (up to 30 times) more computationally efficient than a conventional multistate model, while maintaining comparable parameter accuracy. We then apply the END model to white stork (Ciconia ciconia) capture-recapture data from Germany across 101 hexagonal spatial units, a spatial resolution at which a conventional multistate model is computationally infeasible. We estimate natal dispersal among units jointly with spatial variation in survival and recruitment. This allows us to identify areas of lower or higher survival, earlier or delayed recruitment, and dispersal probabilities among all units. By combining estimated dispersal probabilities with existing data on the number of juveniles born in each spatial unit, we estimate natal dispersal in terms of numbers of individuals and identify units with positive or negative net migration, sources and sinks. 4. Overall, our approach moves capture-recapture analyses from estimating natal dispersal among a few spatial units to inferring dispersal networks and assessing their demographic consequences across large domains. Our approach is applicable to many spatially structured capture-recapture datasets, opening new opportunities for studying spatial population dynamics.

The global expansion of Black Soldier Fly (BSF), Hermetia illucens (L.), production systems for organic waste management has increased the need to better understand its reproductive biology in order to optimize mass-rearing programs. In this study, we macroscopically characterized chronological morphological changes in the internal genitalia of adult H. illucens reared on a sustainable alternative larval diet based on coffee pulp and corn bran. Morphological assessments and dissections were conducted on female and male reproductive tracts at 3, 6, and 9 days after adult emergence. Overall, the general organization of both reproductive systems was consistent with previous descriptions. A notable observation was the presence of a tripartite fertilization chamber in females, composed of three distinct compartments apparently associated with the three spermathecae. The functional significance of this anatomical organization remains to be determined. Females showed progressively advanced ovarian development and reached the clearest morphological indicators of reproductive maturity at 9 days, while males showed the greatest testicular distention and opacity at the same age. Compared with maturation times reported in previous studies using conventional larval diets, these observations suggest a later pattern of reproductive maturation under the coffee pulp-based diet. The observed differences may be associated with the nutritional composition and carbohydrate-to-protein balance of the larval diet. These results provide chronological and iconographic information that may contribute to the optimization of laboratory rearing protocols and the use of coffee by-products in H. illucens bioconversion systems.