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The establishment and spread of invasive species are directly related to intersexual interactions as dispersal and reproductive success are related to distribution, effective population size, and population growth. Accordingly, populations established by r‐selected species are particularly difficult to suppress or eradicate. One such species, the red swamp crayfish (Procambarus clarkii) is established globally at considerable ecological and financial costs to natural and human communities. Here, we develop a single nucleotide polymorphism (SNP) loci panel for P. clarkii using restriction‐associated DNA‐sequencing data. We use the SNP panel to successfully genotype 1800 individuals at 930 SNPs in southeastern Michigan, USA. Genotypic data were used to reconstruct pedigrees, which enabled the characterization of P. clarkii's mating system and statistical tests for associations among environmental, demographic, and phenotypic predictors and adult reproductive success estimates. We identified juvenile cohorts using genotype‐based pedigrees, body size, and sampling timing, which elucidated the breeding phenology of multiple introduced populations. We report a high prevalence of multiple paternity in each surveyed waterbody, indicating polyandry in this species. We highlight the use of newly developed rapid genomic assessment tools for monitoring population reproductive responses, effective population sizes, and dispersal during ongoing control efforts. [ABSTRACT FROM AUTHOR]

Parallel laser photogrammetry (PLP), which consists of attaching two or three parallel laser beams at a known inter‐beam distance to a camera, can be used to collect morphological measurements of organisms noninvasively. The lasers project onto the photo being taken, and because the inter‐beam distance is known, they act as a scale for image analysis programs like ImageJ. Traditionally, this method has been used to measure larger morphological traits (e.g., limb length, crown‐rump length) to serve as proxies for overall body size, whereas applications to smaller anatomical features remain limited. To that end, we used PLP to measure the testes of 18 free‐living mantled howler monkeys (Alouatta palliata) at La Selva Biological Station, Costa Rica. We tested whether this method could reliably measure this relatively small and globular morphology, and whether it could detect differences among individuals. We tested reliability in three ways: within‐photo (coefficient of variation [CV] = 4.7%), between‐photo (CV = 5.5%), and interobserver (intraclass correlation = 0.92). We found an average volume of 36.2 cm3 and a range of 16.4–54.4 cm3, indicating variation in testes size between individuals. Furthermore, these sizes are consistent with a previous study that collected measurements by hand, suggesting that PLP is a useful method for making noninvasive measurements of testes. Research Highlights: Testes measurements are a critical data type that can elucidate key questions related to sperm competition and endocrine disruption, and deriving the measurements noninvasively is a great benefit to conservation effortsWe collected and measured photos of 18 individual adult mantled howler monkeys (Alouatta palliata) from La Selva, Costa Rica via parallel laser photogrammetryWe used three tests of repeatability to provide evidence that parallel laser photogrammetry can be used to measure the testes of a large‐bodied nonhuman primate noninvasively while being precise and accurate [ABSTRACT FROM AUTHOR]

Abstract This study analyses body condition and digestive/metabolic parameters of Odontesthesargentinensis from Mar Chiquita Coastal Lagoon (MChCL) during different ovary maturity phases (II: developing; III: spawning capable; IIIas: actively spawning subphase). Silverside individuals in phases II and III maintained their body condition, while it improved in actively spawning subphase. Total weight and Fulton’s condition factor increase in 70% and 50%, respectively. No changes were observed during the ovary maturation phases in hepatosomatic index and intestinal coefficient. Maltase activity in the intestine remained unchanged, while Aminopeptidase-N was higher, about 300%, in the spawning capable phase (III). Alkaline phosphatase in the intestine was unchanged pointing out the maintenance of intestinal homeostasis. Liver glycogen concentration decreased, about 40%, in the actively spawning subphase (IIIas), while muscle glycogen abruptly decreased in phase III and recovered in subphase IIIas. In intestinal fat, triglycerides concentration was lower 70% in subphase IIIas, while no changes occurred in liver and muscle. Muscle protein concentration decreased about 50% in actively spawning subphase. The findings shed light on the remarkable adaptability of this population of O. argentinensis from MChCL to support its gonadal maturation and active spawning maintaining and even improving its physical condition.

Sand tigers are frequently observed at shipwrecks and other artificial reef habitats off North Carolina (USA), but data about occupancy, movement ecology, and site fidelity are lacking. Spot A Shark USA researchers used Wildbook© photoidentification software to spot map sand tigers in images provided by recreational SCUBA divers, or collected from remotely operated vehicles, and an offshore live-streaming camera. We uniquely identified 1837 sand tigers, 101 of which were resighted on more than one date between 2005-2021. Sand tigers of both sexes and various ages were found year-round along the northern, central and southern coast. We identified shipwrecks or artificial reef sites with consistently high numbers of shark encounters reported, sometimes with seasonal occupancy patterns. Resighted sharks were often encountered at the same or nearby locations, confirming high levels of residency and site fidelity to specific locations. Together, the mating scars seen on 121 female sand tigers and 202 females documented with rotund abdomens consistent with pregnancy highlight the importance of NC waters for reproduction. We also quantified other characteristics of the sand tigers visible in the photographs including wounds, parasitic copepods, and attached fishing gear. Our results reflect the importance of habitats off the NC coast to the movement and reproductive ecology of sand tigers at multiple life history stages. Sand tiger populations have declined in the Northwest Atlantic, so information about residence at specific locations, seasonal patterns of occupancy, and sexdependent behaviors associated with migration and reproduction are important to future management and conservation of the species. [ABSTRACT FROM AUTHOR]

Summary: Serotiny is an adaptive trait that allows certain woody plants to persist in stand‐replacing fire regimes. However, the mechanisms by which serotinous cones avoid seed necrosis and nonserotinous species persist in landscapes with short fire cycles and serotinous competitors remain poorly understood.To investigate whether ovulate cone traits that enhance seed survival differ between serotinous and nonserotinous species, we examined cone traits in 24 species within Pinaceae and Cupressaceae based on physical measurements and cone heating simulations using a computational fluid dynamics model.Fire‐relevant cone traits were largely similar between cone types; those that differed (e.g. density and moisture) conferred little seed survival advantage under simulated fire. The most important traits influencing seed survival were cone size and seed depth within the cone, which was found to be an allometric function of cone mass for both cone types.Thus, nonserotinous cones should not suffer significantly greater seed necrosis than serotinous cones of equal size. Closed nonserotinous cones containing mature seeds may achieve substantial regeneration after fire if they are sufficiently large relative to fire duration and temperature. To our knowledge, this is the most comprehensive study of the effects of fire‐relevant cone traits on conifer regeneration supported by physics‐based fire simulation. [ABSTRACT FROM AUTHOR]

Context: Human activities are having a significant impact on biodiversity worldwide, to the extent that we are in the midst of the sixth mass extinction event. Although a substantial proportion of species globally have an elevated risk of extinction, some species are poorly known and there is insufficient information available to adequately assess their risk of extinction. Aims and methods: One such species is the glossy grass skink (Pseudemoia rawlinsoni), a widespread but enigmatic lizard species in south-eastern Australia. In order to improve our knowledge of its life history, and particularly its generation length, we examined museum specimens collected from across the range of the species, supplemented with measurements from field-caught individuals. Key results: We estimated that the species reaches sexual maturity in 3 years, at approximately 40 mm snout–vent length. Its generation length was estimated as 5 years. Sexual dimorphism was evident, and female body size was positively related to litter size. Although there was no evidence for substantial variation in morphology across the range of the glossy grass skink, a phylogeographic analysis using mitochondrial DNA sequence data (ND4) revealed the presence of seven genetic sublineages (up to 5.1% genetic divergence) within the species. Conclusions: The glossy grass skink appears to be a single, but widespread and genetically variable, species. Implications: Our study demonstrates how a targeted, multifaceted study can be effective at rapidly gathering data that can be used to contribute vital information to the assessment of extinction risk in Data Deficient species. Conservation efforts are often inhibited by a lack of information on a species; but we show it is possible to inform extinction risk with rapidly gathered data. We found that the glossy grass skink (Pseudemoia rawlinsoni) is a widespread, geographically variable species that matures in 3 years and has a generation length of 5 years. This information, in combination with other field-based studies, indicates that the glossy grass skink meets the criteria for listing as a threatened species. [ABSTRACT FROM AUTHOR]

Abstract Background Energy demands associated with pregnancy and lactation are significant forces in mammalian evolution. To mitigate increased energy costs associated with reproduction, female mammals have evolved behavioural and physiological responses. Some species alter activity to conserve energy during pregnancy and lactation, while others experience changes in metabolism and fat deposition. Restructuring of gut microbiota with shifting reproductive states may also help females increase the energy gained from foods, especially during pregnancy. The goal of this study was to examine the relationships among behaviour, gut microbiota composition, and reproductive state in a wild, non-human primate to better understand reproductive ecology. We combined life history data with > 13,000 behavioural scans and 298 fecal samples collected longitudinally across multiple years from 33 white-faced capuchin monkey (Cebus imitator) females. We sequenced the V4 region of the 16S rRNA gene and used the DADA2 pipeline to analyze microbial diversity. We used PICRUSt2 to assess putative functions. Results Reproductive state explained some variation in activity, but overall resting behaviours were relatively stable across pregnancy and lactation. Foraging was less frequent among females in the early stage of nursing compared to the cycling stage, though otherwise remained at comparable levels. Maximum temperature was a strong, significantly positive predictor of resting, while social dominance had a small but significantly negative effect on resting. Ecological variables such as available fruit biomass and rainfall had a small but significantly positive effects on measures of foraging time. Gut microbial community structure, including richness, alpha diversity, and beta diversity remained stable across the reproductive cycle. In pairwise comparisons, pregnant females exhibited increased relative abundances of multiple microbial ASVs, suggesting small changes in relation to reproductive state. Reproductive state was not linked to differential abundance of putative metabolic pathways. Conclusions Previous data suggest that activity budget and the gut microbiome shifts considerably during reproduction. The present study finds that both activity and gut microbial communities are less associated with reproduction compared to other predictors, including ecological contexts. This suggests that behavioural flexibility and gut microbial community plasticity is contrained by ecological factors in this population. These data contribute to a broader understanding of plasticity and stability in response to physiological shifts associated with mammalian reproduction.

The black rat (Rattus rattus) poses a severe threat to food security and public health in Madagascar, where it is a major cause of pre‐ and post‐harvest crop losses and an important reservoir for many zoonotic diseases, including plague. Elsewhere, ecologically based rodent management (EBRM) strategies have been developed using ecological information to inform decisions on where and when to target control. EBRM could deliver improved health and well‐being outcomes in Madagascar if adapted to the local ecological context. Using data collected from removal studies, we explored spatio‐temporal patterns in the breeding activity of the black rat (R. rattus) in domestic and agricultural habitats across Madagascar and investigated to what extent these trends are influenced by rainfall and rat density. We identified clear spatio‐temporal variation in the seasonality of R. rattus reproduction. Reproduction was highly seasonal both inside and outside of houses, but seasonal trends varied between these two habitats. Seasonal trends were explained, in part, by variation in rainfall; however, the effect of rainfall on reproductive rates did itself vary by season and habitat type. A decline in breeding intensity with increasing rat density was recorded outside of houses. This has important implications for control, as populations may compensate for removal through increased reproduction. We recommend that sustained control initiated before the main breeding season, combined with improved hygiene and adequate rodent‐proofing in homes and grain stores, could curtail population growth and reduce pre‐ and post‐harvest losses provided that these measures overcome the compensatory response of rodent populations. [ABSTRACT FROM AUTHOR]

Background: Energy demands associated with pregnancy and lactation are significant forces in mammalian evolution. To mitigate increased energy costs associated with reproduction, female mammals have evolved behavioural and physiological responses. Some species alter activity to conserve energy during pregnancy and lactation, while others experience changes in metabolism and fat deposition. Restructuring of gut microbiota with shifting reproductive states may also help females increase the energy gained from foods, especially during pregnancy. The goal of this study was to examine the relationships among behaviour, gut microbiota composition, and reproductive state in a wild, non-human primate to better understand reproductive ecology. We combined life history data with > 13,000 behavioural scans and 298 fecal samples collected longitudinally across multiple years from 33 white-faced capuchin monkey (Cebus imitator) females. We sequenced the V4 region of the 16S rRNA gene and used the DADA2 pipeline to analyze microbial diversity. We used PICRUSt2 to assess putative functions. Results: Reproductive state explained some variation in activity, but overall resting behaviours were relatively stable across pregnancy and lactation. Foraging was less frequent among females in the early stage of nursing compared to the cycling stage, though otherwise remained at comparable levels. Maximum temperature was a strong, significantly positive predictor of resting, while social dominance had a small but significantly negative effect on resting. Ecological variables such as available fruit biomass and rainfall had a small but significantly positive effects on measures of foraging time. Gut microbial community structure, including richness, alpha diversity, and beta diversity remained stable across the reproductive cycle. In pairwise comparisons, pregnant females exhibited increased relative abundances of multiple microbial ASVs, suggesting small changes in relation to reproductive state. Reproductive state was not linked to differential abundance of putative metabolic pathways. Conclusions: Previous data suggest that activity budget and the gut microbiome shifts considerably during reproduction. The present study finds that both activity and gut microbial communities are less associated with reproduction compared to other predictors, including ecological contexts. This suggests that behavioural flexibility and gut microbial community plasticity is contrained by ecological factors in this population. These data contribute to a broader understanding of plasticity and stability in response to physiological shifts associated with mammalian reproduction. [ABSTRACT FROM AUTHOR]

Genetic diversity in over-exploited and threatened species has important, but often neglected, implications for conservation. In South Africa, the bark of the regionally endangered pepper-bark tree, Warburgia salutaris, is extensively harvested for subsistence medicine. We developed 11 polymorphic microsatellite markers to examine the genetic diversity and structure among 227 W. salutaris individuals sampled from across much of its range in South Africa's Kruger National Park (KNP) and 31 trees growing in local nurseries. We also tested the cross-amplification success of these markers in two closely related species, Warburgia elongata (IUCN listed as Endangered) and W. stuhlmannii (IUCN listed as Vulnerable). Contrary to our expectations, we found evidence of clonality and for high genetic diversity in all wild KNP sub-populations of W. salutaris. We identified between 114 and 149 unique multi-locus genotypes in the 258 individuals included in our analyses. Bayesian assignment tests identified three distinct genetic clusters that are represented by the sampled KNP sub-population of W. salutaris, with minimal geographic structure and some admixture. Three genetic clusters were also identified among all sampled individuals, i.e., KNP and nursery trees. Nursery W. salutaris germplasm comprised unique genotypes with similar levels of observed heterozygosity to the wild population. High levels of clonality and reported self-incompatibility, along with short distance pollination, likely explain the lack of recent sexual recruitment (i.e., reduced fruit set and lack of seedlings) in the wild population. These findings will be useful to identify sub-populations where genets may be sampled to maximize genetic diversity within subpopulations for restoration throughout KNP. [ABSTRACT FROM AUTHOR]

Sand tigers are frequently observed at shipwrecks and other artificial reef habitats off North Carolina (USA), but data about occupancy, movement ecology, and site fidelity are lacking. Spot A Shark USA researchers used Wildbook© photoidentification software to spot map sand tigers in images provided by recreational SCUBA divers, or collected from remotely operated vehicles, and an offshore live-streaming camera. We uniquely identified 1837 sand tigers, 101 of which were resighted on more than one date between 2005–2021. Sand tigers of both sexes and various ages were found year-round along the northern, central and southern coast. We identified shipwrecks or artificial reef sites with consistently high numbers of shark encounters reported, sometimes with seasonal occupancy patterns. Resighted sharks were often encountered at the same or nearby locations, confirming high levels of residency and site fidelity to specific locations. Together, the mating scars seen on 121 female sand tigers and 202 females documented with rotund abdomens consistent with pregnancy highlight the importance of NC waters for reproduction. We also quantified other characteristics of the sand tigers visible in the photographs including wounds, parasitic copepods, and attached fishing gear. Our results reflect the importance of habitats off the NC coast to the movement and reproductive ecology of sand tigers at multiple life history stages. Sand tiger populations have declined in the Northwest Atlantic, so information about residence at specific locations, seasonal patterns of occupancy, and sex-dependent behaviors associated with migration and reproduction are important to future management and conservation of the species.

The influence of abiotic and biotic factors on the temporal pattern of calling and breeding for many temperate anurans is well understood. However, few studies have documented patterns of reproduction in explosive-breeding tropical frogs or incorporated multiple environmental factors in their analyses, especially across multiple breeding seasons. We combine long-term natural history observations and automated data collection methods with boosted regression tree (BRT) analysis to determine the phenology and determinants of explosive breeding in the gliding treefrog, Agalychnis spurrelli. We monitored breeding for a total of 418 days across three breeding seasons and determined the relative importance of several environmental factors on the probability of calling and breeding activity. Our study population of A. spurrelli on Costa Rica's Osa Peninsula forms breeding aggregations up to 11 times per year during 1–2-day long explosive-breeding events, from late May to mid-September. Calling and breeding activity are strongly and positively related to accumulated rainfall during the previous 24 and 48–24 h before, particularly rainfall during the afternoon and evening. Day-of-year, days since breeding occurred, and lunar phase also influence reproductive activity. This study provides the first description and analysis of the phenology and factors that predict explosive breeding in A. spurrelli and illustrates the value of using automated data collection paired with BRTs for the analysis of complex ecological data. La influencia de factores abióticos y bióticos en el patrón temporal de cantos y reproducción de muchos anuros de zonas templadas es bien conocida. Sin embargo, pocos estudios han documentado patrones de reproducción en ranas tropicales, que se reproducen de manera explosiva, o han incorporado múltiples factores ambientales en sus análisis, especialmente a lo largo de múltiples temporadas de reproducción. Combinamos observaciones de historia natural a largo plazo y métodos automatizados de recolectar datos con análisis de árboles de regresión y técnicas de remuestreo ('boosted regression trees', BRT) para determinar la fenología y los determinantes de la reproducción explosiva en la rana planeadora, Agalychnis spurrelli. Monitoreamos la reproducción durante un total de 418 días a través de tres temporadas de reproducción y determinamos la importancia relativa de varios factores ambientales en la probabilidad de cantos y reproducción. Nuestra población de estudio de A. spurrelli en la Península de Osa en Costa Rica forma agregaciones reproductivas hasta 11 veces por año, los eventos de reproducción explosiva tienen 1 a 2 días de duración, desde finales de mayo hasta mediados de septiembre. Los cantos y la reproducción están fuerte y positivamente relacionados con la acumulación de lluvia en las 24 y 48 a 24 horas anteriores, particularmente durante la tarde y la noche. El día del año, los días desde la última reproducción, y la fase lunar también influyen la reproducción. Este estudio es la primera descripción y análisis de la fenología y los factores que predicen la reproducción explosiva en A. spurrelli e ilustra el valor de utilizar la recolección de datos automatizada junto con BRT para el análisis de datos ecológicos complejos. [ABSTRACT FROM AUTHOR]

Objective: Three competing hypotheses might explain the widely documented intrapopulation larger‐fish‐upstream phenomenon. The age‐phased recruitment hypothesis posits that fish spawn downstream and move upstream as they age and grow, the static population with growth and mortality gradients hypothesis posits that fish spawn throughout a riverscape and growth is greater upstream while recruitment is greater downstream, and the colonization cycle hypothesis posits that fish spawn upstream, larvae drift downstream, and individuals move upstream as they age and grow. Methods: We tested for the larger‐fish‐upstream pattern using populations of Silver Chub Macrhybopsis storeriana in the Arkansas and Ohio rivers, as well as investigated longitudinal variation in reproductive investment (Arkansas River), age structure for adult fish (Arkansas River), and number and occurrence of age‐0 fish (Ohio River). Result: The larger‐fish‐upstream pattern was temporally persistent in both riverscapes. In the Arkansas River, reproductive investment was greatest upstream, where initiation of spawning likely occurred based on gonadosomatic indices. Adult fish were most numerous in the Arkansas River 125–175 km upstream from Kaw Reservoir, with age‐2 fish numbers peaking farther upstream compared with age‐1 fish. In the Ohio River, age‐0 fish counts increased downstream and were rare among the shortest river fragments (<100 km) between lock‐and‐dam structures. These findings are inconsistent with the age‐phased recruitment hypothesis based on upstream spawning in the Arkansas River and inconsistent with the static population with growth and mortality gradients hypothesis based on virtual absence of age‐2 fish downstream (Arkansas River) and age‐0 fish upstream (Ohio River). The most likely explanation for longitudinal variation in Silver Chub size distribution is downstream drift of ichthyoplankton followed by net upstream movement (i.e., colonization cycle hypothesis), but formal assessments of movement and ova characteristics require more research. Conclusion: Managing multidimensional riverscapes requires insight into the mechanisms that regulate upstream‐to‐downstream patterns in fish populations, and our work underscores a potential size‐related benefit to maintaining broadscale longitudinal connectivity. Impact statementLarger Silver Chub occur farther upstream in two North American rivers and tests of competing hypotheses suggest this pattern is maintained by broad‐scale movement. Indices based on fish lengths could be used to inform management of longitudinal connectivity in large rivers. [ABSTRACT FROM AUTHOR]

Parental investment in offspring provides fitness benefits for progeny but incurs costs for parents. However, in birds there is a paucity of information on the foraging behaviors of altricial young once they leave the nest. Here we report a novel form of food acquisition in an altricial bird that is driven by a fledgling itself rather than its parents. In a population of densely nesting Red-winged Blackbirds (Agelaius phoeniceus) in Eastern Illinois, USA, we encountered multiple instances of a free-moving fledgling present in a focal nest that also had chicks too young to fly. We observed this behavior six different times in the field and obtained detailed video footage of six total instances at three independent nests, with two of these resulting in an apparent acceptance (i.e., feeding) of the focal fledgling by the attending parental adults. In one of the two nests where the fledgling(s) were accepted, feeding adults provisioned the fledgling as much as the average chick in the nest while at the other nest attending adults fed the fledgling above random expectations. Nest integration appears to be a novel form of food acquisition that is distinct from other fledgling self-maintenance behaviors. [ABSTRACT FROM AUTHOR]

Premise of research. Intraspecific differences in plant reproductive traits affect ecological interactions at the population level, leading to evolutionary shifts. Abiotic and biotic factors exert strong selective pressures on functional traits, such as phenology, affecting reproductive success and thereby plant fitness. Here we evaluated the occurrence of intraspecific variation in the reproductive ecology and reproductive success among three naturally isolated populations of Microlicia laniflora , a narrow-endemic shrub from Brazilian campo rupestre. We asked (i) do isolated populations of M. laniflora differ in their reproductive phenology, floral biology, pollination, and reproductive success and (ii) which abiotic and biotic factors are related to interpopulation differences in reproductive success? Methodology. We sampled three sites varying in altitude and local environment in a tropical mountain vegetation system, the campos rupestres of Serra do Cipó, and tested for interpopulation differences in reproductive phenology, floral biology, pollination interactions, and reproductive success. Pivotal results. Microlicia laniflora populations differed in their reproductive phenology, pollination (frequency of visits and pollinators), and reproductive success, mainly between the lowest-altitude site and the two higher-altitude sites. Flowering and fruiting phenology were strongly seasonal, driven primarily by temperature variation during the reproductive season, with earlier flowering at the higher-altitude sites. There, lower temperatures, larger floral displays, and a higher frequency of pollinator visits positively influenced reproductive success. Conclusions. Our results support the assumption that abiotic and biotic factors jointly act as selective pressures driving phenology and shaping plant reproductive ecology. Our findings evidence the central role played by interpopulation variability in flowering phenology and in pollinator attraction in the evolution of floral and reproductive traits of plant species that are spatially isolated in stressful and megadiverse environments. [ABSTRACT FROM AUTHOR]

The first breeding of osprey (Pandion haliaetus) on Jeju Island, South Korea, were observed in 2015, and ospreys bred on three sites. We found a total of three nests and observed that A site nest bred on successfully from 2017 to 2020. The number of eggs per clutch ranged from two to four, with a mean ± SD of 3.16 ± 0.75. The nesting period varied from 71 days to 79 days, with an average duration of 76.2 ± 3.18 days. The incubation period ranged from 34 days to 38 days, averaging 35.8 ± 1.72 days. Fledging dates ranged from July 4th to 13th. The nest tree species was Pinus thunbergii, and the average tree height was 16.2 ± 3.12 m. On average, the nest height from the ground was 14.8 ± 2.57 m. The average diameter at breast height of the nesting trees was 36.1 ± 2.02 cm. Of the total 19 eggs produced, the hatching rate was 91.4% ± 10.2%, fledgling rate was 68.6% ± 26.9%, and breeding success was 65.6% ± 25.1%. Little ecological information is available on osprey living in South Korea; therefore, this study makes a meaningful contribution to provide baseline ecological data from South Korea for this species.

Temporal patterns in spawning and juvenile recruitment can have major effects on population size and the demographic structure of coral reef fishes. For harvested species, these patterns are crucial in determining stock size and optimizing management strategies such as seasonal closures. For the commercially important coral grouper (Plectropomus spp.) on the Great Barrier Reef, histological studies indicate peak spawning around the summer new moons. Here we examine the timing of spawning activity for P. maculatus in the southern Great Barrier Reef by deriving age in days for 761 juvenile fish collected between 2007 and 2022, and back-calculating settlement and spawning dates. Age-length relationships were used to estimate spawning and settlement times for a further 1002 juveniles collected over this period. Unexpectedly, our findings indicate year-round spawning activity generates distinct recruitment cohorts that span several weeks to months. Peak spawning varied between years with no clear association with environmental cues, and little to no alignment with existing seasonal fisheries closures around the new moon. Given the variability and uncertainty in peak spawning times, this fishery may benefit from additional and longer seasonal closures, or alternative fisheries management strategies, to maximize the recruitment contribution from periods of greatest reproductive success. [ABSTRACT FROM AUTHOR]

Species of Chamaelirium are known to be highly diversified in sexual characters, but there has been no detailed empirical approach to elucidate the mechanism and process of sexual diversification in the genus. This paper reports the results of population‐based analyses on various sexual aspects of C. hisauchianum endemic to Japan. Of the 20 populations surveyed, eight (40%) were composed of facultative hermaphrodites highly labile in sexual expression, exhibiting a wide range of gradational variation from hermaphroditism through andromonoecy to male. The remaining 12 populations (60%) consisted of females and facultative hermaphrodites. In them, 11.8–30.9% (mean 22.2%) of the individuals were female. With no reciprocal sex changes, females and facultative hermaphrodites were regarded as, plausibly genetically determined, discrete sex morphs. In contrast, sexual expression in both sex morphs appeared resource dependent. Besides the difference in floral sexual traits, the average ratio of ovuliferous flowers in females was higher than that in facultative hermaphrodites. The production of ovuliferous flowers by females was less susceptible to both field and cultivated conditions and tended to be significantly relatively higher under unfavorable growing conditions. Females were thus less plastic (or more persistent) in producing ovuliferous flowers (or female organs) than facultative hermaphrodites irrespective of internal and external conditions. In all populations, andromonoecious plants dominated (50.8–100%), which appeared to reflect the high plasticity in sex allocation of facultative hermaphrodites. The different modes of sex allocation were regarded as secondary sex characters and presumably stem from a difference in easiness or attainability of sexual reproduction between the two sex morphs. [ABSTRACT FROM AUTHOR]

The reproductive ecology of the Andean Condor Vultur gryphus is poorly known. This note describes reproductive events of individual breeding pairs. We describe the minimum distances between nest sites, breeding success, elevation and the use of nesting cliffs of different breeding pairs of Andean Condors in the north-central Andes of Ecuador. We undertook 840 hours of observations of eight nesting events in areas on an elevational gradient from 2500 m to 4500 m during 2018 and 2019. Nesting events in Ecuador since 1996, were also reviewed which provided us a total of 21 breeding attempts at 16 nest sites. Minimum distances between the sites of breeding attempts were 25 m (since 1996) and 310 m (during the fieldwork). The nearest neighbour distance of Andean Condors simultaneously sharing the same cliff during partially overlapping breeding was 550 m and in different cliffs 2720 m. Breeding success was 0.75 and higher in reused nests. The results present previously unknown information that contributes to reproductive ecology and emphasizes the importance of the cliffs as critical areas for the conservation and permanence of the Andean Condor where management actions are urgent. [ABSTRACT FROM AUTHOR]

Understanding the reproductive biology is of great importance in the development of novel hybrids in ornamental plants. Pollen fitness-related traits are crucial for the pollination success in any plant species including dendrobiums. The aim of the study was to determine and compare the fitness traits of ten commercial Dendrobium hybrids and two indigenous Dendrobium species, D. crumenatum and D. anosmum found in Sri Lanka. We measured pollen viability, pollen germinability, and fruit production after controlled pollination. The effect of storage temperature on D. crumenatum pollen viability was evaluated to establish a suitable pollen storage method to improve future breeding programmes, as the flowering of dendrobiums is seasonal. The reproductive ecology of selected dendrobiums was studied by the observations of visits of natural pollinators and by assessing floral morphology to predict their potential pollinators. Six commercial hybrids had non-viable pollen while D. crumenatum showed the highest pollen germinability under both in vivo and in vitro conditions. Ninety percent of the commercial hybrids failed in vitro pollen germination whereas under in vivo conditions 50% were successful. Self-incompatibility in D. crumenatum was observed in both hand-pollination and under natural pollination. Pollen of D. crumenatum can be stored for two weeks at 9°C maintaining viability and germinability. Selected dendrobiums have shown adaptations to melittophily, suggesting the pollination by bees. Findings indicated a reduction of male fitness in most of the commercial Dendrobium hybrids and a higher fruit set is seen in selfing than cross-pollination. The present study provides information for developing conservation strategies and future hybridization programmes in paleotropical dendrobiums.

Plant–animal mutualisms such as seed dispersal are key interactions for sustaining plant range shifts. It remains elusive whether the organization of interactions with seed dispersers is reconfigured along the expansion landscape template and, if so, whether its effects accelerate or slow colonization. Here we analyse plant–frugivore interactions in a scenario of rapid population expansion of a Mediterranean juniper. We combined network analyses with field surveys, sampling interactions between individual plants and frugivores by DNA-barcoding and phototrapping over two seasons. We assess the role of intrinsic and extrinsic intraspecific variability in shaping interactions and we estimate the individual plant contributions to the seed rain. The whole interaction network was highly structured, with a distinct set of modules including individual plants and frugivore species arranged concordantly along the expansion gradient. The modular configuration was partially shaped by individual neighbourhood context (density and fecundity) and phenotypic traits (cone size). Interaction reconfiguration resulted in a higher and more uneven propagule contribution, with most effective dispersers having a prominent role at the colonization front stand, where a distinct subset of early arriving plants dominated the seed rain. Our study offers new insights into the key role of mutualistic interactions in colonization scenarios by promoting fast plant expansion processes. [ABSTRACT FROM AUTHOR]

Traits related to reproduction and dispersal drive the assembly and dynamics of species communities and can explain and predict how species respond to habitat loss and fragmentation and to the changing climate. For fungi, such links remain poorly known.We examine how spore production rate, a key demographic trait, is influenced by the interaction between environmental conditions and species traits. We monitored the spore production of 97 wood‐inhabiting fungal species on 107 decaying logs for 2 years and analysed the data with a hierarchical community model.Our analysis demonstrates clear species differences in seasonal patterns, with spring and summer release dominating in perennial species, contrary to the commonly held view of autumn as the primary "mushroom season". Many species follow a diurnal pattern with a higher spore release rate during the night. Such patterns in release timing have important implications for dispersal, as shown by recent model simulations.The overall level of spore release was negatively correlated with spore size, providing new evidence that fungi face the classic trade‐off of investing either in the number or size of offspring.We found that different species within the functional group of wood‐inhabiting fungi display alternative strategies in spore release timing and along the trade‐off between offspring size and number. Linking our findings to previously reported correlations between spore size and other traits, we propose a new conceptualization of life history strategies in wood‐inhabiting fungi, with implications for species' ability to survive the ongoing biodiversity crisis. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

In this study, we report the observation of potential seed dispersers of the endemic to Mexico and narrowly distributed Ceratozamia norstogii (Zamiaceae). Camera traps were installed in front of two plants of Ceratozamia norstogii and cone phenology until their maturity and disintegration was determined. The female cone of Ceratozamia norstogii has a development of ten months, from the time it emerges until it disintegrates. We were able to identify three stages of cone development: 1) Pre-pollination phase, 2) Pollination phase and 3) Seed maturation phase. Our results support an animal-dispersal hypothesis in Ceratozamia. Three mammals [a mouse (Pteromiscus sp.), a southern spotted skunk (Spilogale angustifrons) and a kinkajou (Potus flavus)] were recorded biting, carrying or removing seeds of Ceratozamia norstogii. The camera traps recorded no evidence of birds or other mammals coming to the cones to feed. Thus, interaction of frugivores with seeds occurs at night. The most frequent visitor was the mouse, followed by the southern spotted skunk and the kinkajou. Significant differences (GLM, p< 0.05) in visitor frequency and time for interaction were found between species. We believe that the mouse is probably the most effective seed disperser for Ceratozamia norstogii. The results presented here have evolutionary implications that can be scaled to the entire genus Ceratozamia. Specifically, short-distance dispersal promotes allopatric speciation in this group of plants.

Shifts in flowering phenology have been studied in detail in the northern hemisphere and are a key plant response to climate change. However, there are relatively fewer data on species' phenological shifts in the southern hemisphere.We combined historic field data, data from herbarium specimens dating back to 1842 and modern field data for 37 Australian species to determine whether species were flowering earlier in the year than they had in the past. We also combined our results with data compiled in the southern and northern hemispheres, respectively, to determine whether southern hemisphere species are showing fewer advances in flowering phenology through time.Across our study species, we found that 12 species had undergone significant shifts in flowering time, with four species advancing their flowering and eight species delaying their flowering. The remaining 25 species showed no significant shifts in their flowering phenology. These findings are important because delays or lack of shifts in flowering phenology can lead to mismatches in trophic interactions between plants and pollinators or seed dispersers, which can have substantial impacts on ecosystem functioning and primary productivity. Combining our field results with data compiled from the literature showed that only 58.5% of southern hemisphere species were advancing their flowering time, compared with 81.6% of species that were advancing their flowering time in the northern hemisphere. Our study provides further evidence that it is not adequate for ecologists to assume that southern hemisphere ecosystems will respond to future climate change in the same way as ecosystems north of the Equator.Synthesis. Field data and data from the literature indicate that southern hemisphere species are showing fewer advances in their flowering phenology through time, especially in comparison to northern hemisphere species. [ABSTRACT FROM AUTHOR]

The seasonal timing of flowering and fruiting is crucial for the reproductive success of plants and for resource availability to animals. Although plants synchronize their reproductive timing to coincide with appropriate seasons by responding to environmental cues, seasonal variations in temperature and precipitation vary minimally in very wet tropical environments. To explore the latitudinal cline in the reproductive phenology of the Fagaceae in Asia, we analyzed phenology data for a total of 94, 121, and 219 species from Thailand, Malesia, and China, respectively, in the three genera of Fagaceae, Quercus, Castanopsis, and Lithocarpus. We found that Quercus and Castanopsis showed flowering peaks in April in China. In Thailand, the peak shifted to an earlier month, and the peak disappeared in Malesia. The flowering period lengthened with decreasing latitude in the animal-pollinated genera Castanopsis and Lithocarpus. However, this was not the case for the wind-pollinated genus Quercus. The fruiting period lengthened with decreasing latitude in all three genera. We examined the relationship between reproductive phenology and climatic factors. The combination of monthly temperature and precipitation best explained the monthly change in the proportion of flowering and fruiting species in China in all three genera. However, climatic factors had almost no impact on the predictive ability of the model in Malesia. Our results on phenological shifts in the family Fagaceae, from the temperate climates and seasonal tropics to the humid tropics, provide valuable information for predicting phenological changes in future climate change. [ABSTRACT FROM AUTHOR]

Warburgia salutaris (pepperbark tree) is an endangered species greatly valued in South Africa for use in traditional medicine. In one of the few remaining W. salutaris conserved sites, the Kruger National Park (KNP), fruit production is extremely low, with a relatively low proportion of juveniles in the population. This study aimed firstly, to understand the reproductive ecology of W. salutaris and, secondly, to investigate factors that may contribute to the limited fruit (and seed) output in KNP by comparing results from KNP with a reproductively successful orchard in Eston, KwaZulu-Natal Province. In the first part of the study, potential pollinators were observed and collected for further analysis; four pollination treatments (i.e. autonomous self-, geitonogamous self-, cross- and natural pollination) were set-up to elucidate the breeding system; pollen viability was assessed; and pollen tube growth for self-, cross- and natural pollination was compared. In the second part of the study, fruit production and maturation was assessed; seed dispersers were identified; and germination success of seeds from natural and cultivated populations were compared. Pollination trials revealed that W. salutaris is likely self-incompatible as self-pollinated flowers in neither KNP nor Eston resulted in mature fruit. In addition, the majority of flowers that began to form fruit in the natural-bagged treatment (i.e. naturally pollinated flowers bagged to protect from seed predation) were aborted. Pollen viability was high across both the KNP sub-populations and Eston, while percentage pollen tube occurrence for self- and cross-pollination was higher in Eston than KNP. Mature KNP fruit were only present on three trees in one sub-population during the two-year study period. Ceratitis cosyra, the marula fly, was the only seed predator in W. salutaris fruit, and 20% of collected KNP fruit were affected by seed predation. Frugivore observations in a supplemental population at Leshiba Mountain Retreat (Limpopo Province) revealed that baboons (Papio ursinus) and vervet monkeys (Chlorocebus aethiops pygerythrus) eat W. salutaris fruit (but not the exocarp) and possibly orally discard the seeds at a later stage. Seeds from KNP fruit were viable and had the highest percentage germination, followed by Eston, and Leshiba. Overall, W. salutaris has many floral visitors, with Lepidoptera the most likely pollinators, pollen viability is high, and seeds that are produced germinate successfully. Therefore, the impaired reproductive output in KNP appears to be in the high occurrence of aborted fruit, supporting the hypothesis that the species relies on clonal reproduction and resprouting to persist in KNP. However, long-term reliance on clonal reproduction may impair the ability to reproduce sexually, which is ultimately necessary to establish genetically diverse genets that can adapt to environmental changes.

Parental care is extremely diverse but, despite much research, why parental care evolves is poorly understood. Here we address this outstanding question using egg attendance, the simplest and most common care form in many taxa. We demonstrate that, in amphibians, terrestrial egg deposition, laying eggs in hidden locations and direct development promote the evolution of female egg attendance. Male egg attendance follows the evolution of hidden eggs and is associated with terrestrial egg deposition but not with direct development. We conclude that egg attendance, particularly by females, evolves following changes in reproductive ecology that are likely to increase egg survival, select for small clutches of large eggs and/or expose eggs to new environmental challenges. While our results resolve a long‐standing question on whether reproductive ecology traits are drivers, consequences or alternative solutions to caring, they also unravel important, yet previously unappreciated, differences between the sexes. [ABSTRACT FROM AUTHOR]

Genus Asarum (Aristolochiaceae) shows diverse floral morphology and is hypothesized to have diversified as a result of pollinator‐mediated selection. Yet most aspects of their reproductive ecology, including pollinators, remain unclear. This study focuses on A. costatum and A. minamitanianum in Japan, a sister species pair having remarkable differences in calyx lobe length (10–20 mm and 70–180 mm, respectively). The objectives of this study are to elucidate multiple aspects of reproductive ecology of these two species and obtain evolutionary insights into floral organ elongation.We adopted combined approaches, including field observations, molecular analyses and cultivation experiments, such as pollinator observation for 3 years, fine‐scale spatial genetic analysis of 769 individuals, paternity analysis based on 566 seeds over 4 years, and control pollination experiments.Both Asarum species had strong spatial genetic structures, indicating limited seed dispersal. Pollinator observation revealed that flies and ground‐dwelling insects visited flowers of both species, but that the pollinator fauna differed between the species. The visitation rate of flies was extremely low but was more than twice as high in the species with an elongated floral appendage. Paternity analysis revealed A. minamitanianum was predominantly outcrossing, while A. costatum showed a wide range of selfing rates among fruits.These two Asarum species are likely adapted to fly pollination in the shady forest understorey, where available pollinator fauna is limited. In addition, although its function remains unclear, the elongated calyx lobe of A. minamitanianum could have evolved for effective pollen dispersal by attracting fly visitors. [ABSTRACT FROM AUTHOR]

1. The animal dispersal hypothesis predicts that mast seeding can increase dispersal rate of seeds by dispersers and enhance reproductive success of plants. However, in contrast to pollination efficiency and predator satiation hypothesis, the animal dispersal hypothesis has received mixed support. 2. Using 12-year data on fruit production and seedling recruitment of a fleshy-fruited tree rowan (Sorbus aucuparia, Rosaceae), we tested if an increase in the fruit production at the population level results in higher proportion of fruits recruiting into seedlings. Recruitment was recorded near (under rowans) and far (under heterospecifics) from conspecifics. Higher recruitment rates under rowans would support predator satiation hypothesis. Higher recruitment rates under heterospecific trees, where fruits can only arrive with animal assistance, would support animal dispersal hypothesis. 3. High population-level fruit production increased the proportion of fruits recruiting into seedlings both near and far from rowans. In contrast, high individuallevel fruit production did not have a positive effect on the proportion of fruits recruiting into seedlings. 4. Synthesis. Population-level synchronisation of fruit production is required to generate a more effective plant regeneration. Our findings show that masting enhances seedling recruitment through predator satiation and increased seed dispersal by frugivores. The results provide support for both animal dispersal and predator satiation hypotheses indicating that both mechanisms can operate simultaneously. [ABSTRACT FROM AUTHOR]

Range expansion in plant populations, especially at the colonization front, can be either limited by disproportionately large effects of antagonistic interactions or facilitated by their release. How the strength of antagonistic interactions changes along successional gradients during range expansion is still poorly documented, especially when diverse assemblages of plant antagonists (rodents, invertebrates and birds) combine within interaction networks.We study the changes in individual‐based, predispersal seed–pulp predator networks along a colonization gradient in a rapidly expanding Juniperus phoenicea population in Doñana National Park (SW Spain). Additionally, we analysed the role of individual plant traits and neighbourhood attributes in network configuration by using Exponential Random Graph Models.Seven seed–pulp consumer animal species varied significantly in their frequency of interaction and prevalence. While invertebrate species were well‐established in old and intermediately mature stands, greenfinch Chloris chloris was dominant at the colonization front. Variable species roles and spread of interactions among individual plants generated changes in the configuration of interactions during plant expansion.Individual plant traits strongly determined the topology of these networks, although with differences between stands. Increasing individual crop size and seeds per cone increased the interaction odds of individual plants, while seed viability showed the opposite effect. The network topology at the colonization front appeared less driven by individual traits, possibly because of the short interaction history of this recently established area. The disproportionately large effect of C. chloris in these recently established stands, potentially resulted in large seed losses during range expansion.Synthesis. Turnover of antagonistic interactions, characterized the colonization front, resulting in more heterogeneous interaction strengths among individual plants. We found no evidence for a complete or sizeable antagonistic release of J. phoenicea at the colonization front promoting this rapid expansion. It becomes necessary to explore interactions with seed dispersers to understand how antagonistic and mutualistic plant–animal interactions balance during range expansion. Our study highlights the importance of an individual‐based approach in understanding how interactions are structured and driven in natural changing landscapes. [ABSTRACT FROM AUTHOR]

Background: The pollen ornate surface of flowering plants has long fascinated and puzzled evolutionary biologists for their variety. Each pollen grain is contained within a pollen wall consisting of intine and exine, over which the lipoid pollen coat lies. The cytology and molecular biology of the development of the intine and exine components of the pollen wall are relatively well characterised. However, little is known about the pollen coat, which confers species specificity. We demonstrate three types of pollen coat in Zingiberaceae, a mucilage-like pollen coat and a gum-like pollen coat, along with a pollen coat more typical of angiosperms. The morphological differences between the three types of pollen coat and the related molecular mechanisms of their formation were studied using an integrative approach of cytology, RNA-seq and positive selection analysis. Results: Contrary to the 'typical' pollen coat, in ginger species with a mucilage-like (Caulokaempferia coenobialis, Cco) or gum-like (Hornstedtia hainanensis, Hhn) pollen coat, anther locular fluid was still present at the bicellular pollen (BCP) stage of development. Nevertheless, there were marked differences between these species: there were much lower levels of anther locular fluid in Hhn at the BCP stage and it contained less polysaccharide, but more lipid, than the locular fluid of Cco. The set of specific highly-expressed (SHE) genes in Cco was enriched in the 'polysaccharide metabolic process' annotation term, while 'fatty acid degradation' and 'metabolism of terpenoids and polyketides' were significantly enriched in SHE-Hhn. Conclusions: Our cytological and comparative transcriptome analysis showed that different types of pollen coat depend on the residual amount and composition of anther locular fluid at the BCP stage. The genes involved in 'polysaccharide metabolism' and 'transport' in the development of a mucilage-like pollen coat and in 'lipid metabolism' and 'transport' in the development of a gum-like pollen coat probably evolved under positive selection in both cases. We suggest that the shift from a typical pollen coat to a gum-like or mucilage-like pollen coat in flowering plants is an adaptation to habitats with high humidity and scarcity of pollinators. [ABSTRACT FROM AUTHOR]

In this study, we report the observation of potential seed dispersers of the endemic to Mexico and narrowly distributed Ceratozamia norstogii (Zamiaceae). Camera traps were installed in front of two plants of Ceratozamia norstogii and cone phenology until their maturity and disintegration was determined. The female cone of Ceratozamia norstogii has a development of ten months, from the time it emerges until it disintegrates. We were able to identify three stages of cone development: 1) Pre-pollination phase, 2) Pollination phase and 3) Seed maturation phase. Our results support an animal-dispersal hypothesis in Ceratozamia. Three mammals [a mouse (Pteromiscus sp.), a southern spotted skunk (Spilogale angustifrons) and a kinkajou (Potus flavus)] were recorded biting, carrying or removing seeds of Ceratozamia norstogii. The camera traps recorded no evidence of birds or other mammals coming to the cones to feed. Thus, interaction of frugivores with seeds occurs at night. The most frequent visitor was the mouse, followed by the southern spotted skunk and the kinkajou. Significant differences (GLM, p< 0.05) in visitor frequency and time for interaction were found between species. We believe that the mouse is probably the most effective seed disperser for Ceratozamia norstogii. The results presented here have evolutionary implications that can be scaled to the entire genus Ceratozamia. Specifically, short-distance dispersal promotes allopatric speciation in this group of plants. [ABSTRACT FROM AUTHOR]

The Orange-fronted Parakeet, Eupsittula canicularis, nests in arboreal termite mounds during the dry season, but little is known of the species' biology and reproductive ecology. This study reports the nest-site characteristics and reproductive behavior of the Orange-fronted Parakeet at one nest in secondary succession vegetation at the Puerto Escondido Botanical Garden of the Universidad del Mar, Oaxaca coastal region. The nest-termitaria had 117 liters volume, and was located in a live Ceiba parvifolia tree, at 6.32 m above the ground. The nesting cycle comprised from December 2021 with nest construction, to April 2022 when the young fledged. Throughout incubation and in the early days of chick rearing, the female remained inside the nest and depended on the male for food. Subsequently, both the male and female fed the chicks at least twice a day, spending a few minutes per visit. During late chick rearing, the pair increased the frequency of visits to the nest to a maximum of four visits over the observation intervals. These finding highlight the importance of promoting regeneration of natural vegetation in successional forests that may supply resources for species with specific nesting characteristics. [ABSTRACT FROM AUTHOR]

Wood turtles (Glyptemys insculpta) have been suffering range-wide population declines since the 1900s. Most monitoring efforts of these turtles involve population surveys to assess population size and viability but relatively few investigate rates of reproductive success. We collected four consecutive years (2013–2016) of wood turtle nesting data at a nesting site in northwestern New Jersey; population-level hatching success was unusually low. Furthermore, annual, intra-individual hatch rates and comparisons between natural and artificial incubation revealed that approximately half of all females usually produced clutches with low (50%) or highly variable, ranging from 0 to 100%. Thus, some adult females are potentially making much larger contributions to the next generation than others. A repeatability analysis suggested that approximately 60% of the hatch rate variability observed in this population can be attributed to maternal identity. The remaining 40% may be attributed to the random environmental factors that are often theorized to be potential reasons for reduced hatch rates in turtle populations (e.g., unsuitable incubation conditions, flooding, desiccation, egg infertility, egg damage due to improper handling by researchers, root and insect predation, and microbial infection). The ultimate causes of this population’s hatching success variability are uncertain, but maternally-linked hatching failure in turtle populations could be associated with inbreeding, infertility, senescence, inadequate maternal diets, or environmental contamination. This study indicates that commonly suggested hypotheses for hatching failure, such as unsuitable incubation conditions or infertility, are unlikely to explain all of the hatch rate variability in some turtle populations. This study also reveals a cryptic conservation implication for vulnerable turtle populations: that the presence of many nesting females and nests does not necessarily assure high or even sustainable reproductive rates. When coupled with the high rates of nest predation and low juvenile survival rates that are common in most turtle populations, the exceedingly low hatch rates observed in this population suggest that recruitment in some turtle populations could be severely hindered even when nests are protected in the field or incubated in laboratory settings.

Abstract Testosterone is strongly associated with the annual development of antlers in cervids, but endocrine research on wild, freely breeding ungulates is often done without repeated capture of known‐aged individuals. As a result, our knowledge on how testosterone fluctuates over the course of a lifetime and variation in lifetime patterns among individuals is limited. We investigated patterns of testosterone in a freely breeding population of white‐tailed deer (Odocoileus virginianus) in Alabama, USA, that breeds in January. Testosterone peaked during the height of the breeding season, despite this period occurring approximately 2 months later than in most temperate‐region white‐tailed deer populations. Age‐related differences in testosterone were only prevalent during the breeding season, with bucks ≥3.5 years old having greater testosterone (853 ng/dl ± 96 SE; p = 0.012) than bucks 1.5–2.5 years old (364 ng/dl ± 100 SE). Additionally, an individual's testosterone level as a yearling was not positively associated with their lifetime maximum testosterone level (p = 0.583), and an individual's mean testosterone level was positively associated with lifetime testosterone variation (p

The terminal investment hypothesis (TIH) predicts that individuals with favorable prospects for future reproduction (i.e., high residual reproductive value, RRV) should moderate current reproductive investment in favor of growth, survival, and future reproduction, whereas those with low RRV should "terminally invest" by diverting somatic resources towards current reproduction at the expense of future reproduction. However, support for the TIH in wild animal populations is fragmentary, and the ecological contexts of terminal investment remain poorly known. We report a remarkable case of simultaneous terminal investment involving five sympatric species of the electric knifefish genus Brachyhypopomus, from Amazonian floodplain and terra firme stream habitats. We found that terminal investment is synchronized by seasonal breeding, in response to circannual environmental variation in mortality risk. Four species exhibit a uniseasonal iteroparous (annual) life history with complete post‐reproductive mortality after a single breeding season. One species (Brachyhypopomus beebei) exhibits a 2‐year multiseasonal iteroparous life history with breeding in two seasons and post‐reproductive mortality after the second. In mature females and (most) males of the annual species, as well as in both mature female and male second‐year (but not first‐year) B. beebei, we documented an increase in two metrics of reproductive effort (size‐adjusted gonad mass and electric signal amplitude) and a concomitant reduction in somatic condition (size‐adjusted somatic mass), all in response to proximity to the end of the common breeding season, when RRV approximates zero. In mature first‐year B. beebei, we documented neither an increase in reproductive effort nor a decline in somatic condition, implying an alternative strategy of reproductive restraint. Our findings support Kirkwood's disposable soma theory, which posits that death by reproductive exhaustion can be delayed if terminal investment is replaced by reproductive restraint, allowing individuals to survive and breed in a subsequent season. Deferral of the terminal investment response in annual species, and the origin of a gonadal regression‐regeneration sequence, may open pathways for rapid evolutionary transitions to multiseasonal iteroparity. Excepting the age (year‐group) dependency of terminal investment in B. beebei, we were unable to identify intrinsic cues or extrinsic environmental cues for the terminal investment response in Brachyhypopomus. [ABSTRACT FROM AUTHOR]

Many plant species have floral morphologies that restrict access to floral resources, such as pollen or nectar, and only a subset of floral visitors can perform the handling behaviors required to extract restricted resources. Due to the time and energy required to extract resources from morphologically complex flowers, these plant species potentially compete for pollinators with co‐flowering plants that have more easily accessible resources. A widespread floral mechanism restricting access to pollen is the presence of tubular anthers that open through small pores or slits (poricidal anthers). Some bees have evolved the capacity to remove pollen from poricidal anthers using vibrations, giving rise to the phenomenon of buzz‐pollination. These bee vibrations that are produced for pollen extraction are presumably energetically costly, and to date, few studies have investigated whether buzz‐pollinated flowers may be at a disadvantage when competing for pollinators' attention with plant species that present unrestricted pollen resources. Here, we studied Cyanella hyacinthoides (Tecophilaeaceae), a geophyte with poricidal anthers in the hyperdiverse Cape Floristic Region of South Africa, to assess how the composition and relative abundance of flowers with easily accessible pollen affect bee visitation to a buzz‐pollinated plant. We found that the number of pollinator species of C. hyacinthoides was not influenced by community composition. However, visitation rates to C. hyacinthoides were reduced when the relative abundances of flowers with more accessible resources were high. Visitation rates were strongly associated with petal color, showing that flower color is important in mediating these interactions. We conclude that buzz‐pollinated plants might be at a competitive disadvantage when many easily accessible pollen sources are available, particularly when competitor species share its floral signals. [ABSTRACT FROM AUTHOR]

Biodiversity is in global decline during the Anthropocene. Declines have been caused by multiple factors, such as habitat removal, invasive species, and disease, which are often targets for conservation management. However, conservation interventions are under threat from climate change induced weather extremes. Weather extremes are becoming more frequent and devastating and an example of this was the 2019/2020 Australian drought and mega-fires. We provide a case study the impacts of these extreme weather events had on a population of the threatened frog Litoria aurea that occurs in a constructed habitat which was designed to reduce the impact of introduced fish and chytrid-induced disease. We aimed to determine what factors influenced persistence so that the design of wetlands can be further optimised to future-proof threatened amphibians. We achieved this with 4 years (2016–2020) of intensive capture–recapture surveys during austral spring and summer across nine wetlands (n = 94 repeat surveys). As hypothesized, drought caused a sharp reduction in population size, but persistence was achieved. The most parsimonious predictor of survival was an interaction between maximum air temperature and rainfall, indicating that weather extremes likely caused the decline. Survival was positively correlated with wetland vegetation coverage, positing this is an important feature to target to enhance resilience in wetland restoration programs. Additionally, the benefits obtained from measures to reduce chytrid prevalence were not compromised during drought, as there was a positive correlation between salinity and survival. We emphasize that many species may not be able to persist under worse extreme weather scenarios. Despite the potential for habitat augmentation to buffer effects of extreme weather, global action on climate change is needed to reduce extinction risk. [ABSTRACT FROM AUTHOR]

Thermal extremes alter population processes, which can result in part from temperature-induced movement at different spatial and temporal scales. Thermal thresholds for animal movement likely change based on underlying thermal physiology and life-history stage, a topic that requires greater study. The intertidal porcelain crab Petrolisthes cinctipes currently experiences temperatures that can reach near-lethal levels in the high-intertidal zone at low tide. However, the thermal thresholds that trigger migration to cooler microhabitats, and the extent to which crabs move in response to temperature, remain unknown. Moreover, the influence of reproductive status on these thresholds is rarely investigated. We integrated demographic, molecular, behavioral, and physiological measurements to determine if behavioral thermal limits varied due to reproductive state. Demographic data showed a trend for gravid, egg bearing, crabs to appear more often under rocks in the cooler intertidal zone where crab density is highest. In situ expression of 31 genes related to stress, metabolism, and growth in the field differed significantly based on intertidal elevation, with mid-intertidal crabs expressing the gene for the reproductive yolk protein vitellogenin (vg) earlier in the season. Furthermore, VG protein levels were shown to increase with density for female hemolymph. Testing for temperatures that elicit movement revealed that gravid females engage in heat avoidance behavior at lower temperatures (i.e., have a lower voluntary thermal maximum, VTmax) than non-gravid females. VTmax was positively correlated with the temperature of peak firing rate for distal afferent nerve fibers in the walking leg, a physiological relationship that could correspond to the mechanistic underpinning for temperature dependent movement. The vulnerability of marine organisms to global change is predicated by their ability to utilize and integrate physiological and behavioral strategies in response to temperature to maximize survival and reproduction. Interactions between fine-scale temperature variation and reproductive biology can have important consequences for the ecology of species, and is likely to influence how populations respond to ongoing climate change. [ABSTRACT FROM AUTHOR]

So far, oil‐rewarding flowers are known to be pollinated only by oil‐collecting bees, which gather and use lipids for larval feed and nest building. As honeybees do not have oil‐collecting appendages on their legs, they have not been associated with pollination of such flowers. In a predominantly Apis pollinated and food deceptive clade of wild Cymbidiums, we investigated the reproductive strategy of Cymbidium aloifolium, hitherto unknown for its floral oil reward. Our study demonstrates the requisites for establishment of mutualistic interaction between the oil flower and Apis cerana indica, a corbiculate bee. Success in pollination requires learning by honeybees to access the food reward, thereby displaying cognitive ability of the pollinator to access the customized reward. Morphometric matching between orchid flowers and the pollinator, and that between pollinia and stigmatic cavity also appear to be essential in the pollination success. Absence of pollinator competition and prolonged flower‐handling time are suggested to promote floral constancy. The present study highlights the need to explore the spectrum of pollination rewards pursued by honeybees, which may include unconventional composition of floral resources. [ABSTRACT FROM AUTHOR]

Abstract Many plant species have floral morphologies that restrict access to floral resources, such as pollen or nectar, and only a subset of floral visitors can perform the handling behaviors required to extract restricted resources. Due to the time and energy required to extract resources from morphologically complex flowers, these plant species potentially compete for pollinators with co‐flowering plants that have more easily accessible resources. A widespread floral mechanism restricting access to pollen is the presence of tubular anthers that open through small pores or slits (poricidal anthers). Some bees have evolved the capacity to remove pollen from poricidal anthers using vibrations, giving rise to the phenomenon of buzz‐pollination. These bee vibrations that are produced for pollen extraction are presumably energetically costly, and to date, few studies have investigated whether buzz‐pollinated flowers may be at a disadvantage when competing for pollinators’ attention with plant species that present unrestricted pollen resources. Here, we studied Cyanella hyacinthoides (Tecophilaeaceae), a geophyte with poricidal anthers in the hyperdiverse Cape Floristic Region of South Africa, to assess how the composition and relative abundance of flowers with easily accessible pollen affect bee visitation to a buzz‐pollinated plant. We found that the number of pollinator species of C. hyacinthoides was not influenced by community composition. However, visitation rates to C. hyacinthoides were reduced when the relative abundances of flowers with more accessible resources were high. Visitation rates were strongly associated with petal color, showing that flower color is important in mediating these interactions. We conclude that buzz‐pollinated plants might be at a competitive disadvantage when many easily accessible pollen sources are available, particularly when competitor species share its floral signals.

Thermal extremes alter population processes, which can result in part from temperature-induced movement at different spatial and temporal scales. Thermal thresholds for animal movement likely change based on underlying thermal physiology and life-history stage, a topic that requires greater study. The intertidal porcelain crab Petrolisthes cinctipes currently experiences temperatures that can reach near-lethal levels in the high-intertidal zone at low tide. However, the thermal thresholds that trigger migration to cooler microhabitats, and the extent to which crabs move in response to temperature, remain unknown. Moreover, the influence of reproductive status on these thresholds is rarely investigated. We integrated demographic, molecular, behavioral, and physiological measurements to determine if behavioral thermal limits varied due to reproductive state. Demographic data showed a trend for gravid, egg bearing, crabs to appear more often under rocks in the cooler intertidal zone where crab density is highest. In situ expression of 31 genes related to stress, metabolism, and growth in the field differed significantly based on intertidal elevation, with mid-intertidal crabs expressing the gene for the reproductive yolk protein vitellogenin (vg) earlier in the season. Furthermore, VG protein levels were shown to increase with density for female hemolymph. Testing for temperatures that elicit movement revealed that gravid females engage in heat avoidance behavior at lower temperatures (i.e., have a lower voluntary thermal maximum, VTmax) than non-gravid females. VTmax was positively correlated with the temperature of peak firing rate for distal afferent nerve fibers in the walking leg, a physiological relationship that could correspond to the mechanistic underpinning for temperature dependent movement. The vulnerability of marine organisms to global change is predicated by their ability to utilize and integrate physiological and behavioral strategies in response to temperature to maximize survival and reproduction. Interactions between fine-scale temperature variation and reproductive biology can have important consequences for the ecology of species, and is likely to influence how populations respond to ongoing climate change.

Environmental changes, for example, in rainfall and land use, lead to changes in the environment experienced by subsequent generations of plant species. Environmental conditions of maternal plants can influence the fitness and phenotypes of subsequent generations via non‐genetic mechanisms: transgenerational plasticity (TGP). However, relevant empirical evidence remains scarce and ambiguous. What are the adaptive consequences of TGP for plants in the face of environmental change? For how many generations does the TGP effect remain?We tried to answer these questions by measuring life‐history traits and reproductive characteristics of progeny plants of the diaspore‐heteromorphic annual halophyte Atriplex centralasiatica in a 3‐year TGP experiment covering F0, F1 and F2 and partly F3. Plants from diaspore types A (low dispersal and high germination ability) and C (high dispersal and low germination ability) were grown in favourable versus stressful salinities over three generations in a fully factorial design.Transgenerational plasticity of plants grown in favourable versus stressful salinities decreased from F2 → F1 → F0. Compared to the favourable condition, the stressful condition decreased the length of the vegetative period, increased the length of reproductive time, reproductive allocation and progeny diaspore size. Salinity tolerance and phenotypic plasticity were higher in plants from diaspore A than in those from diaspore C. In the stressful condition, plants produced less plant biomass, larger diaspores, a higher proportion of diaspore C, but lower proportion of diaspore A. Production of the proportion of diaspore C increased with increase in number of previous generations that experienced stress. The stress experience of the great‐great grandmother (F0) continued into the lower A:C ratio of the F3 diaspores.Synthesis. Our findings provide evidence for the 'escape strategy' of A. centralasiatica: TGP could spread the risk of environmental adversity by delaying seed germination temporally and broadening seed dispersal spatially, thus allowing plants to cope with environmental heterogeneity. Specifically, the trade‐off in reproductive allocation between diaspores A and C enables plants to develop divergent strategies. New research should reveal the extent to which wide‐ranging taxa can benefit from TGP and whether even (great)‐great grandmother might be the starting point of TGP. [ABSTRACT FROM AUTHOR]

A vast majority of angiosperms are pollinated by animals, and a decline in the number and diversity of insects often affects plant reproduction through pollen limitation. This phenomenon may be particularly severe in rare plant species, whose populations are shrinking. Here, we examined the variability in factors shaping reproductive success and pollen limitation in red-listed Polemonium caeruleum L. During a 5-year study in several populations of P. caeruleum (7–15, depending on year), we assessed the degree of pollen limitation based on differences in seed set between open-pollinated (control) and hand-pollinated flowers. We analysed the effects of flower visitors, population size, and meteorological data on plant reproductive success and pollen limitation. Our study showed that pollen limitation rarely affected P. caeruleum populations, and was present mainly in small populations. Pollen limitation index was negatively affected by the size of population, visitation frequency of all insects, and when considering the visitation frequency of individual groups, also by honeybee visits. Seed production in control treatment was positively influenced by the population size, average monthly precipitation in June and visits of hoverflies, while visits of honeybees, average monthly temperature in September, and average monthly precipitation in August influenced seed production negatively. As generalist plant P. caeruleum can be pollinated by diverse insect groups, however, in small populations their main visitors, the honeybees and bumblebees, may be less attracted, eventually leading to the disappearance of these populations. In pollination of P. caeruleum managed honeybees may play a dual role: while they are the most frequent and efficient flower visitors, their presence decreases seed set in open-pollinated flowers, which is most probably related to efficient pollen collection by these insects. [ABSTRACT FROM AUTHOR]

A vast majority of angiosperms are pollinated by animals, and a decline in the number and diversity of insects often affects plant reproduction through pollen limitation. This phenomenon may be particularly severe in rare plant species, whose populations are shrinking. Here, we examined the variability in factors shaping reproductive success and pollen limitation in red-listed Polemonium caeruleum L. During a 5-year study in several populations of P. caeruleum (7–15, depending on year), we assessed the degree of pollen limitation based on differences in seed set between open-pollinated (control) and hand-pollinated flowers. We analysed the effects of flower visitors, population size, and meteorological data on plant reproductive success and pollen limitation. Our study showed that pollen limitation rarely affected P. caeruleum populations, and was present mainly in small populations. Pollen limitation index was negatively affected by the size of population, visitation frequency of all insects, and when considering the visitation frequency of individual groups, also by honeybee visits. Seed production in control treatment was positively influenced by the population size, average monthly precipitation in June and visits of hoverflies, while visits of honeybees, average monthly temperature in September, and average monthly precipitation in August influenced seed production negatively. As generalist plant P. caeruleum can be pollinated by diverse insect groups, however, in small populations their main visitors, the honeybees and bumblebees, may be less attracted, eventually leading to the disappearance of these populations. In pollination of P. caeruleum managed honeybees may play a dual role: while they are the most frequent and efficient flower visitors, their presence decreases seed set in open-pollinated flowers, which is most probably related to efficient pollen collection by these insects.