T. Shimamoto, T. Taki, A. Kumaki, A. Motohashi, H. Tamatani, G. Oshima, J. Tanaka, T. Yamamoto
Hair hormone analysis has received increasing attention in the fields of wildlife management and conservation over the last decade. However, few studies focused on sex steroid hormones, even though hair sex steroid hormone analysis has the potential to provide information on an individual's reproductive health, leading to a better understanding of animal reproductive biology and the assessment of individual and population health. Here, we tested the assay validation and examined whether hair progesterone concentration (HPC) differs between different sexes and age classes in the Asian black bear, Ursus thibetanus. We also investigated the effects of reproductive condition, age, and body condition index (BCI) on HPC to determine the utility of hair progesterone analysis in bears. The assay validation was reported in our study. We found a significantly higher HPC in adult females than in juvenile females and juvenile and adult males. In addition, we found no effects of age and BCI on HPC but a significant positive effect of reproductive condition, as the HPC in breeding adult females was significantly higher than in nonbreeding adult females. These results suggest that hair progesterone analysis has the potential to evaluate the reproductive condition of Asian black bears.
{"title":"Reproductive health from hair: Validation and utility of hair progesterone analysis in the Asian black bear, Ursus thibetanus","authors":"T. Shimamoto, T. Taki, A. Kumaki, A. Motohashi, H. Tamatani, G. Oshima, J. Tanaka, T. Yamamoto","doi":"10.1111/jzo.13213","DOIUrl":"https://doi.org/10.1111/jzo.13213","url":null,"abstract":"Hair hormone analysis has received increasing attention in the fields of wildlife management and conservation over the last decade. However, few studies focused on sex steroid hormones, even though hair sex steroid hormone analysis has the potential to provide information on an individual's reproductive health, leading to a better understanding of animal reproductive biology and the assessment of individual and population health. Here, we tested the assay validation and examined whether hair progesterone concentration (HPC) differs between different sexes and age classes in the Asian black bear, <jats:italic>Ursus thibetanus</jats:italic>. We also investigated the effects of reproductive condition, age, and body condition index (BCI) on HPC to determine the utility of hair progesterone analysis in bears. The assay validation was reported in our study. We found a significantly higher HPC in adult females than in juvenile females and juvenile and adult males. In addition, we found no effects of age and BCI on HPC but a significant positive effect of reproductive condition, as the HPC in breeding adult females was significantly higher than in nonbreeding adult females. These results suggest that hair progesterone analysis has the potential to evaluate the reproductive condition of Asian black bears.","PeriodicalId":17600,"journal":{"name":"Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142179727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Gregorič, S. G. Quiñones‐Lebrón, M. Kuntner, I. Agnarsson
The ideal free distribution (IFD) theory predicts that individuals are free to move among habitat patches and distribute among them “ideally,” in order to maximize individual evolutionary fitness. Size and quality of habitat patches then should directly impact the number of individuals occupying them, and connectivity of habitat patches likely plays a role if dispersal is limited. However, habitat patches can be distributed so that movement no longer can be considered free, for example, when patches are isolated. Challenges stemming from patch delimitation and detection rate of occupants further complicate efforts attempting to resolve such patterns. Here, we utilize as habitat patches the orb webs of four different populations belonging to three golden orb weaver spider species, Nephila pilipes (Fabricius, 1793), Nephilingis livida (Vinson, 1863), and Trichonephila clavipes (Linnaeus, 1767), and the obligate spider kleptoparasites (Argyrodinae, Theridiidae) that are associated with their webs. We examine how the IFD predicts the abundance of kleptoparasites under different patterns of patch size and distribution. We found that larger host webs, that is, habitat patches that contain more resources, are occupied by a higher number of kleptoparasitic spiders, regardless of their degree of isolation. Although the free movement prediction is often violated in natural systems, we find no evidence for habitat patch connectivity affecting the abundance of kleptoparasites, indicating that their dispersal ability facilitates the location and colonization of habitat patches regardless of their isolation. Therefore, our results support the interaction between argyrodine kleptoparasitic spiders and the webs of golden orb weavers to be a suitable natural system for studying the IFD.
{"title":"Exploring resource patch occupancy: patch size, but not connectivity, explains the abundance of spider kleptoparasites in golden orb webs","authors":"M. Gregorič, S. G. Quiñones‐Lebrón, M. Kuntner, I. Agnarsson","doi":"10.1111/jzo.13212","DOIUrl":"https://doi.org/10.1111/jzo.13212","url":null,"abstract":"The ideal free distribution (IFD) theory predicts that individuals are free to move among habitat patches and distribute among them “ideally,” in order to maximize individual evolutionary fitness. Size and quality of habitat patches then should directly impact the number of individuals occupying them, and connectivity of habitat patches likely plays a role if dispersal is limited. However, habitat patches can be distributed so that movement no longer can be considered free, for example, when patches are isolated. Challenges stemming from patch delimitation and detection rate of occupants further complicate efforts attempting to resolve such patterns. Here, we utilize as habitat patches the orb webs of four different populations belonging to three golden orb weaver spider species, <jats:italic>Nephila pilipes</jats:italic> (Fabricius, 1793), <jats:italic>Nephilingis livida</jats:italic> (Vinson, 1863), and <jats:italic>Trichonephila clavipes</jats:italic> (Linnaeus, 1767), and the obligate spider kleptoparasites (Argyrodinae, Theridiidae) that are associated with their webs. We examine how the IFD predicts the abundance of kleptoparasites under different patterns of patch size and distribution. We found that larger host webs, that is, habitat patches that contain more resources, are occupied by a higher number of kleptoparasitic spiders, regardless of their degree of isolation. Although the free movement prediction is often violated in natural systems, we find no evidence for habitat patch connectivity affecting the abundance of kleptoparasites, indicating that their dispersal ability facilitates the location and colonization of habitat patches regardless of their isolation. Therefore, our results support the interaction between argyrodine kleptoparasitic spiders and the webs of golden orb weavers to be a suitable natural system for studying the IFD.","PeriodicalId":17600,"journal":{"name":"Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142223629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Many animals communicate using multiple sensory modes (e.g., vibratory, visual, chemical), and there is current interest in the role of multimodal signals in mate choice. We tested the hypotheses that male Gladicosa bellamyi wolf spiders (Lycosidae) court females using multimodal signals and that these signals were related to male mating success. Using a laser Doppler vibrometer and video camera, we characterized the vibratory and visual courtship signals of male G. bellamyi. Males courted females with a vibratory signal made of three components: pulses of stridulation, abdominal percussion, and a third unknown percussive element (presumed to arise from rapid abdomen tapping), along with two unique visual displays, a foreleg extension/tap and squared leg arch. Female G. bellamyi show no apparent vibratory signals, but possess visual receptivity displays comparable to some other female lycosid species. We found a strong correlation between the vibratory stridulation component and the visual foreleg extension/tapping display of males, suggesting a multimodal signal. Higher rates of courtship signaling, both visual and vibratory, were associated with increased copulatory success. We conclude that male G. bellamyi exhibits multimodal courtship communication, with simultaneous complex vibratory signals and visual displays, and that higher rates of these signals increase the probability of mating in this species.
{"title":"Multimodal courtship communication in a wolf spider","authors":"M. M. Lallo, G. W. Uetz","doi":"10.1111/jzo.13209","DOIUrl":"https://doi.org/10.1111/jzo.13209","url":null,"abstract":"Many animals communicate using multiple sensory modes (e.g., vibratory, visual, chemical), and there is current interest in the role of multimodal signals in mate choice. We tested the hypotheses that male <jats:italic>Gladicosa bellamyi</jats:italic> wolf spiders (Lycosidae) court females using multimodal signals and that these signals were related to male mating success. Using a laser Doppler vibrometer and video camera, we characterized the vibratory and visual courtship signals of male <jats:italic>G. bellamyi</jats:italic>. Males courted females with a vibratory signal made of three components: pulses of stridulation, abdominal percussion, and a third unknown percussive element (presumed to arise from rapid abdomen tapping), along with two unique visual displays, a foreleg extension/tap and squared leg arch. Female <jats:italic>G. bellamyi</jats:italic> show no apparent vibratory signals, but possess visual receptivity displays comparable to some other female lycosid species. We found a strong correlation between the vibratory stridulation component and the visual foreleg extension/tapping display of males, suggesting a multimodal signal. Higher rates of courtship signaling, both visual and vibratory, were associated with increased copulatory success. We conclude that male <jats:italic>G. bellamyi</jats:italic> exhibits multimodal courtship communication, with simultaneous complex vibratory signals and visual displays, and that higher rates of these signals increase the probability of mating in this species.","PeriodicalId":17600,"journal":{"name":"Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142223627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mouse‐like rodents often take cover in natural shelters or burrow underground where they build simple nests. A few species build extensive shelters above ground, called lodges, mounds or houses. Here, we present the first phylogenetically controlled comparative study on the ecological factors of habitat heterogeneity, environmental aridity and fire risk related to nesting habits in mouse‐like rodents (Myomorpha, 326 genera). Twenty species from seven genera were found to build lodges, and they mainly occur in arid environments with low fire risk. Most lodge‐building species (14 out of 20) belong to the pack rats (genus Neotoma), which in phylogeny only represent one event of evolution of lodge building and therefore limit the statistical power of the phylogenetically controlled analysis. The Bayesian phylogenetic mixed‐effects models show a phylogenetic signal of 0.43 for 515 Myomorpha species. Under this moderate to strong phylogenetic relatedness, we did not find specific factors being associated to the evolution of sheltering habit in Myomorpha. We suggest studying the importance of aridity combined with low fire risk for lodge building on the species level, for example, by studying the limits of species distribution ranges depending on these factors.
{"title":"Lodge‐building in rodents: relationships with ecological and natural history factors","authors":"J. Qiu, C. Schradin","doi":"10.1111/jzo.13207","DOIUrl":"https://doi.org/10.1111/jzo.13207","url":null,"abstract":"Mouse‐like rodents often take cover in natural shelters or burrow underground where they build simple nests. A few species build extensive shelters above ground, called lodges, mounds or houses. Here, we present the first phylogenetically controlled comparative study on the ecological factors of habitat heterogeneity, environmental aridity and fire risk related to nesting habits in mouse‐like rodents (Myomorpha, 326 genera). Twenty species from seven genera were found to build lodges, and they mainly occur in arid environments with low fire risk. Most lodge‐building species (14 out of 20) belong to the pack rats (genus <jats:italic>Neotoma</jats:italic>), which in phylogeny only represent one event of evolution of lodge building and therefore limit the statistical power of the phylogenetically controlled analysis. The Bayesian phylogenetic mixed‐effects models show a phylogenetic signal of 0.43 for 515 Myomorpha species. Under this moderate to strong phylogenetic relatedness, we did not find specific factors being associated to the evolution of sheltering habit in Myomorpha. We suggest studying the importance of aridity combined with low fire risk for lodge building on the species level, for example, by studying the limits of species distribution ranges depending on these factors.","PeriodicalId":17600,"journal":{"name":"Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142179726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The temporomandibular joint (TMJ) is a distinguishing feature of mammals, and in most mammals includes an articular disc that buffers the loads placed on it by mastication. The disc is well developed in mammals with significant lateral masticatory jaw movements but is absent in toothless mammals, including extant monotremes, although histological studies of developing monotremes have shown rudimentary discs that fail to mature. Platypus (Ornithorhynchus anatinus) grind their food between keratinous pads in the maxillae and lower jaws and are the only edentulate mammals that masticate their food. In this study, we characterize the anatomy of the TMJ of the adult platypus to see if we can reconcile the anatomy, including the absence of the articular disc, with the mandibular movements observed in video recordings. We studied the gross anatomy of the maxillofacial region and the microstructure using microcomputed tomography (micro‐CT) and histological examination. Platypuses had well‐developed masticatory muscles but lacked an articular disc between the mandibular condyle and glenoid fossa. The surface of the glenoid fossa was slightly concave than that of the condylar head was correspondingly slightly convex. The pre‐ and postglenoid processes were not well developed. Micro‐CT showed dense trabecular bone in the anterior part of the condyle, where the lateral pterygoid muscle attached. Histological analysis showed that the surfaces of the condyle and glenoid fossa consisted of dense, avascular and thickened fibrous connective tissue. In addition, well‐developed synovial folds were present. These anatomical characteristics are consistent with both anterior and lateral movements of the mandible, while the thick layer of connective tissue substitutes for a disc by absorbing the mechanical stresses associated with mastication. The failure of the disc primordium to develop cannot be attributed to a lack of muscle development, but the distribution of stresses in the toothless platypus jaw is likely to be different from those in a masticating eutherian.
{"title":"The anatomy of mastication in a toothless mammal: Morphological characteristics of the temporomandibular joint in the platypus (Ornithorhynchus anatinus)","authors":"K. Hayashi, S. C. Nicol, M. Sugisaki, T. Amemiya","doi":"10.1111/jzo.13208","DOIUrl":"https://doi.org/10.1111/jzo.13208","url":null,"abstract":"The temporomandibular joint (TMJ) is a distinguishing feature of mammals, and in most mammals includes an articular disc that buffers the loads placed on it by mastication. The disc is well developed in mammals with significant lateral masticatory jaw movements but is absent in toothless mammals, including extant monotremes, although histological studies of developing monotremes have shown rudimentary discs that fail to mature. Platypus (<jats:italic>Ornithorhynchus anatinus</jats:italic>) grind their food between keratinous pads in the maxillae and lower jaws and are the only edentulate mammals that masticate their food. In this study, we characterize the anatomy of the TMJ of the adult platypus to see if we can reconcile the anatomy, including the absence of the articular disc, with the mandibular movements observed in video recordings. We studied the gross anatomy of the maxillofacial region and the microstructure using microcomputed tomography (micro‐CT) and histological examination. Platypuses had well‐developed masticatory muscles but lacked an articular disc between the mandibular condyle and glenoid fossa. The surface of the glenoid fossa was slightly concave than that of the condylar head was correspondingly slightly convex. The pre‐ and postglenoid processes were not well developed. Micro‐CT showed dense trabecular bone in the anterior part of the condyle, where the lateral pterygoid muscle attached. Histological analysis showed that the surfaces of the condyle and glenoid fossa consisted of dense, avascular and thickened fibrous connective tissue. In addition, well‐developed synovial folds were present. These anatomical characteristics are consistent with both anterior and lateral movements of the mandible, while the thick layer of connective tissue substitutes for a disc by absorbing the mechanical stresses associated with mastication. The failure of the disc primordium to develop cannot be attributed to a lack of muscle development, but the distribution of stresses in the toothless platypus jaw is likely to be different from those in a masticating eutherian.","PeriodicalId":17600,"journal":{"name":"Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142223628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. E. Spencer, C. R. Dickman, A. Greenville, P. Barton, E. G. Ritchie, T. M. Newsome
Carcass scavenging by vertebrates is a critical ecosystem service that is influenced by environmental factors such as season and habitat. However, there is limited understanding of the role that these factors play in shaping scavenging patterns across different bioregions. We used camera traps to monitor vertebrate scavengers at 120 kangaroo (Family: Macropodidae) carcasses that were positioned across different seasons (warm/cool) and habitats (open/closed canopy) in three disparate desert, subalpine and temperate bioregions in Australia. Our survey identified 27 species that scavenged carcasses and revealed clear differences in scavenging patterns across the three bioregions. Carcass use was highest for feral cats, birds of prey, corvids and red foxes in the desert bioregion; for reptiles and dingoes in the temperate bioregion and for feral pigs, possums and dingoes in the subalpine bioregion. Bioregional differences in scavenger guild composition explained >4.6 times more variation in scavenger guild dissimilarity than season and >9.8 times more variation than habitat. Further, habitat had few effects on scavenger communities or carcass detection and use, whereas season was a strong predictor of these responses. Across bioregions, there were some general seasonal and habitat scavenging trends, with mammals and birds often using carcasses more frequently in cooler seasons and birds detecting carcasses faster in open habitat. However, there was also extensive within‐bioregion seasonal variation. For example, depending on bioregion, some animals scavenged more frequently or detected carcasses faster in warmer seasons (i.e. birds and reptiles). Our results show that vertebrate scavenging is mediated by a complex interplay of environmental variables, especially seasonality, which may operate differently across bioregions. These findings have implications for understanding variability in vertebrate scavenging patterns and, in turn, functionally redundant or complementary scavenging processes.
{"title":"Vertebrate scavenging in Australia is shaped by a complex interplay of bioregional, seasonal and habitat factors","authors":"E. E. Spencer, C. R. Dickman, A. Greenville, P. Barton, E. G. Ritchie, T. M. Newsome","doi":"10.1111/jzo.13200","DOIUrl":"https://doi.org/10.1111/jzo.13200","url":null,"abstract":"Carcass scavenging by vertebrates is a critical ecosystem service that is influenced by environmental factors such as season and habitat. However, there is limited understanding of the role that these factors play in shaping scavenging patterns across different bioregions. We used camera traps to monitor vertebrate scavengers at 120 kangaroo (Family: Macropodidae) carcasses that were positioned across different seasons (warm/cool) and habitats (open/closed canopy) in three disparate desert, subalpine and temperate bioregions in Australia. Our survey identified 27 species that scavenged carcasses and revealed clear differences in scavenging patterns across the three bioregions. Carcass use was highest for feral cats, birds of prey, corvids and red foxes in the desert bioregion; for reptiles and dingoes in the temperate bioregion and for feral pigs, possums and dingoes in the subalpine bioregion. Bioregional differences in scavenger guild composition explained >4.6 times more variation in scavenger guild dissimilarity than season and >9.8 times more variation than habitat. Further, habitat had few effects on scavenger communities or carcass detection and use, whereas season was a strong predictor of these responses. Across bioregions, there were some general seasonal and habitat scavenging trends, with mammals and birds often using carcasses more frequently in cooler seasons and birds detecting carcasses faster in open habitat. However, there was also extensive within‐bioregion seasonal variation. For example, depending on bioregion, some animals scavenged more frequently or detected carcasses faster in warmer seasons (i.e. birds and reptiles). Our results show that vertebrate scavenging is mediated by a complex interplay of environmental variables, especially seasonality, which may operate differently across bioregions. These findings have implications for understanding variability in vertebrate scavenging patterns and, in turn, functionally redundant or complementary scavenging processes.","PeriodicalId":17600,"journal":{"name":"Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142179728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I. Belardi, J. Borkowski, L. Lazzeri, R. Banul, G. Pacini, A. Poerling, F. Ferretti
Under an optimal foraging scenario, prey selection would be expected to occur when food resources are abundant. A positive frequency‐dependent prey selection would elicit prey switching when the abundance of main food resources decreases, potentially favouring community resilience to the effects of intensive, selective predation on a single prey. We assessed whether a positive frequency‐dependent prey selection by the wolf Canis lupus occurred in two areas hosting abundant populations of wild ungulates, one in northern (Słowiński National Park, Poland) and the other one in southern (Maremma Regional Park, Italy) Europe, throughout a cold semester. In Słowiński, ungulate community was dominated by red deer Cervus elaphus (57% availability) over wild boar Sus scrofa (35%) and roe deer Capreolus capreolus (8%); wild boar and fallow deer Dama dama (43–37%) were more abundant than roe deer (20%) in Maremma. In both areas, wolf diet was dominated by wild ungulates, with a major use of red deer in Słowiński and wild boar in Maremma. Prey selection occurred in both areas, and it was addressed towards the most abundant prey in Słowiński, that is, the red deer, but only towards the wild boar in Maremma, where the fallow deer was used according to availability. In Slowinski, high red deer density may have driven wolf prey selection, while the shifting of activity rhythms of the fallow deer in the Maremma as antipredator response to wolf presence may have reduced predation. Despite its comparable densities between the two areas, the wild boar was selected in Maremma and under‐used in Słowiński. Results provide partial support to positive frequency‐dependent selection, emphasising the spatiotemporal plasticity of wolf–prey relationships. The relative role of prey density and other factors (e.g., antipredator behavioural responses) should be assessed at longer temporal scales.
{"title":"Spatiotemporal plasticity of prey selection in the wolf","authors":"I. Belardi, J. Borkowski, L. Lazzeri, R. Banul, G. Pacini, A. Poerling, F. Ferretti","doi":"10.1111/jzo.13205","DOIUrl":"https://doi.org/10.1111/jzo.13205","url":null,"abstract":"Under an optimal foraging scenario, prey selection would be expected to occur when food resources are abundant. A positive frequency‐dependent prey selection would elicit prey switching when the abundance of main food resources decreases, potentially favouring community resilience to the effects of intensive, selective predation on a single prey. We assessed whether a positive frequency‐dependent prey selection by the wolf <jats:italic>Canis lupus</jats:italic> occurred in two areas hosting abundant populations of wild ungulates, one in northern (Słowiński National Park, Poland) and the other one in southern (Maremma Regional Park, Italy) Europe, throughout a cold semester. In Słowiński, ungulate community was dominated by red deer <jats:italic>Cervus elaphus</jats:italic> (57% availability) over wild boar <jats:italic>Sus scrofa</jats:italic> (35%) and roe deer <jats:italic>Capreolus capreolus</jats:italic> (8%); wild boar and fallow deer <jats:italic>Dama dama</jats:italic> (43–37%) were more abundant than roe deer (20%) in Maremma. In both areas, wolf diet was dominated by wild ungulates, with a major use of red deer in Słowiński and wild boar in Maremma. Prey selection occurred in both areas, and it was addressed towards the most abundant prey in Słowiński, that is, the red deer, but only towards the wild boar in Maremma, where the fallow deer was used according to availability. In Slowinski, high red deer density may have driven wolf prey selection, while the shifting of activity rhythms of the fallow deer in the Maremma as antipredator response to wolf presence may have reduced predation. Despite its comparable densities between the two areas, the wild boar was selected in Maremma and under‐used in Słowiński. Results provide partial support to positive frequency‐dependent selection, emphasising the spatiotemporal plasticity of wolf–prey relationships. The relative role of prey density and other factors (e.g., antipredator behavioural responses) should be assessed at longer temporal scales.","PeriodicalId":17600,"journal":{"name":"Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142179729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. I. Hernández‐Herrera, H. A. Pérez‐Mendoza, J. Fornoni
Understanding how species respond to environmental changes, particularly in the context of climate change, is crucial for biodiversity conservation. This study focuses on the plastic responses of canyon tree frog (Dryophytes arenicolor) larvae to variations in temperature and pond‐drying, examining potential consequences of climate change. Frog larvae serve as an excellent model due to their high responsiveness to environmental cues during development. We analysed the impact of temperature and pond‐drying on morphological and life‐history traits, via a common garden experiment with individuals from three distinct populations with different ecological conditions. The experiments revealed significant differences in responses among populations, indicating geographic variation in plasticity. Pond‐drying treatments led to reduced survival and reduction of morphological traits and growth, challenging the assumption that tadpoles have adaptive responses to drying conditions. In contrast, temperature treatments showed variable effects, with elevated temperatures generally favouring growth rates, reducing metamorphosis time, and having population‐specific morphological shifts. We emphasize the importance of considering both morphological and life‐history traits, as well as geographic variation, in assessing species' vulnerability to climate change. Furthermore, the integration of environmental standardized plasticity index (ESPI) and relative distances plasticity index (RDPI) in amphibian developmental plasticity will allow to quantify and compare plastic responses among populations and even other amphibian species in which these metrics are obtained in the future. Our results underscore the complexity of phenotypic plasticity, revealing genotype–environment interactions. These findings contribute valuable insights into the potential adaptability of D. arenicolor populations to ongoing climate changes, highlighting the need for comprehensive inter‐population studies for a more nuanced understanding of species' responses to environmental change, and suggest that certain populations may be more vulnerable to extinction or better equipped to handle climate change based on their ability to adapt to environmental change.
{"title":"Geographic variation in developmental plasticity among populations of the canyon treefrog in response to temperature and pond‐drying","authors":"C. I. Hernández‐Herrera, H. A. Pérez‐Mendoza, J. Fornoni","doi":"10.1111/jzo.13202","DOIUrl":"https://doi.org/10.1111/jzo.13202","url":null,"abstract":"Understanding how species respond to environmental changes, particularly in the context of climate change, is crucial for biodiversity conservation. This study focuses on the plastic responses of canyon tree frog (<jats:italic>Dryophytes arenicolor</jats:italic>) larvae to variations in temperature and pond‐drying, examining potential consequences of climate change. Frog larvae serve as an excellent model due to their high responsiveness to environmental cues during development. We analysed the impact of temperature and pond‐drying on morphological and life‐history traits, via a common garden experiment with individuals from three distinct populations with different ecological conditions. The experiments revealed significant differences in responses among populations, indicating geographic variation in plasticity. Pond‐drying treatments led to reduced survival and reduction of morphological traits and growth, challenging the assumption that tadpoles have adaptive responses to drying conditions. In contrast, temperature treatments showed variable effects, with elevated temperatures generally favouring growth rates, reducing metamorphosis time, and having population‐specific morphological shifts. We emphasize the importance of considering both morphological and life‐history traits, as well as geographic variation, in assessing species' vulnerability to climate change. Furthermore, the integration of environmental standardized plasticity index (ESPI) and relative distances plasticity index (RDPI) in amphibian developmental plasticity will allow to quantify and compare plastic responses among populations and even other amphibian species in which these metrics are obtained in the future. Our results underscore the complexity of phenotypic plasticity, revealing genotype–environment interactions. These findings contribute valuable insights into the potential adaptability of <jats:italic>D. arenicolor</jats:italic> populations to ongoing climate changes, highlighting the need for comprehensive inter‐population studies for a more nuanced understanding of species' responses to environmental change, and suggest that certain populations may be more vulnerable to extinction or better equipped to handle climate change based on their ability to adapt to environmental change.","PeriodicalId":17600,"journal":{"name":"Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The random encounter model (REM) is a camera trapping method to estimate population density (i.e. number of individuals per unit area) without the need for individual recognition. The REM can be applied considering camera trap data only by tracking the passages of animals in front of the camera (i.e. sequences). However, it has not been assessed how the number of sequences tracked (i.e. trajectory of the animal reconstructed) influences the REM estimates. In this context, we aimed to gain further insights into the relationship between the number of sequences tracked and reliability in REM estimates to optimize its applicability. We monitored multiple species using camera traps, and we applied REM to estimate population density. We considered red fox Vulpes vulpes, roe deer Capreolus capreolus, fallow deer Dama dama, red deer Cervus elaphus and wild boar Sus scrofa as model species. We tracked from a minimum of 154 (red fox) to a maximum of 527 (red deer) sequences per species, and we then sampled the dataset to simulate different scenarios in which a lower number of sequences were tracked (20, 40, 80 and 160). We also assessed the effect of adjusting the survey period to the minimum necessary to record the desired number of sequences. Our results suggest that tracking around 100 sequences returns a precision level equivalent to the one obtained by tracking a considerably higher number of sequences and reduced and optimized the human effort necessary to apply REM. Tracking less than 40 sequences could result in low precise density estimates. Our results also highlighted the relevance of considering study periods of ca. 2 months to increase the number of sequences recorded and tracking a random sample of them. Our results contribute to the optimization and harmonization of REM as a reference method to estimate wildlife population density without the need for individual identification. We make clear recommendations on the cost‐effective sample size for estimating REM parameters, optimizing the human effort when applying REM, and discouraging REM applications based on low sample sizes.
随机相遇模型（REM）是一种照相机诱捕法，用于估算种群密度（即单位面积内的个体数量），无需识别个体。随机相遇模型只能通过追踪动物在相机前的移动轨迹（即序列）来应用于相机捕获数据。然而，跟踪序列的数量（即重建的动物轨迹）对 REM 估计值的影响还没有进行过评估。在这种情况下，我们的目标是进一步深入了解跟踪序列数与 REM 估计可靠性之间的关系，以优化其适用性。我们使用相机陷阱监测了多个物种，并应用 REM 估算种群密度。我们将赤狐（Vulpes vulpes）、狍子（Capreolus capreolus）、秋鹿（Dama dama）、马鹿（Cervus elaphus）和野猪（Sus scrofa）作为模型物种。我们对每个物种的序列进行了追踪，从最少的 154 个（赤狐）到最多的 527 个（赤鹿），然后我们对数据集进行了取样，模拟了追踪序列数量较少的不同情况（20、40、80 和 160）。我们还评估了将调查时间调整到记录所需序列数所需的最短时间的效果。我们的结果表明，跟踪 100 个左右的序列所获得的精度水平与跟踪更多序列所获得的精度水平相当，并且减少和优化了应用 REM 所需的人力。跟踪少于 40 个序列可能会导致精确度较低的密度估算。我们的研究结果还突出表明，考虑用约 2 个月的研究时间来增加记录序列的数量，并对其中的随机样本进行跟踪是有意义的。我们的研究结果有助于优化和统一 REM，将其作为无需个体识别即可估算野生动物种群密度的参考方法。我们对估算 REM 参数的成本效益样本量、应用 REM 时的人力优化以及基于低样本量的 REM 应用提出了明确的建议。
{"title":"How many sequences should I track when applying the random encounter model to camera trap data?","authors":"P. Palencia, P. Barroso","doi":"10.1111/jzo.13204","DOIUrl":"https://doi.org/10.1111/jzo.13204","url":null,"abstract":"The random encounter model (REM) is a camera trapping method to estimate population density (i.e. number of individuals per unit area) without the need for individual recognition. The REM can be applied considering camera trap data only by tracking the passages of animals in front of the camera (i.e. sequences). However, it has not been assessed how the number of sequences tracked (i.e. trajectory of the animal reconstructed) influences the REM estimates. In this context, we aimed to gain further insights into the relationship between the number of sequences tracked and reliability in REM estimates to optimize its applicability. We monitored multiple species using camera traps, and we applied REM to estimate population density. We considered red fox <jats:italic>Vulpes vulpes</jats:italic>, roe deer <jats:italic>Capreolus capreolus</jats:italic>, fallow deer <jats:italic>Dama dama</jats:italic>, red deer <jats:italic>Cervus elaphus</jats:italic> and wild boar <jats:italic>Sus scrofa</jats:italic> as model species. We tracked from a minimum of 154 (red fox) to a maximum of 527 (red deer) sequences per species, and we then sampled the dataset to simulate different scenarios in which a lower number of sequences were tracked (20, 40, 80 and 160). We also assessed the effect of adjusting the survey period to the minimum necessary to record the desired number of sequences. Our results suggest that tracking around 100 sequences returns a precision level equivalent to the one obtained by tracking a considerably higher number of sequences and reduced and optimized the human effort necessary to apply REM. Tracking less than 40 sequences could result in low precise density estimates. Our results also highlighted the relevance of considering study periods of ca. 2 months to increase the number of sequences recorded and tracking a random sample of them. Our results contribute to the optimization and harmonization of REM as a reference method to estimate wildlife population density without the need for individual identification. We make clear recommendations on the cost‐effective sample size for estimating REM parameters, optimizing the human effort when applying REM, and discouraging REM applications based on low sample sizes.","PeriodicalId":17600,"journal":{"name":"Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Within the breeding sites of anurans, factors at the microhabitat scale can exhibit variations over the years, resulting in temporal fluctuations within these sites. These fluctuations may lead to modifications in “normal larval development” and observable phenotypic changes. These developmental alterations appear to have evolved as shared strategies for achieving reproductive success and ensuring the survival of offspring. In a population of Boana cordobae inhabiting the Central Pampean Sierras (Córdoba, Argentina), the coexistence of pre‐ and prometamorphic tadpoles throughout the year, coupled with variations in size and shape within the same developmental stage, has led us to question about the duration of the larval period, variations in the timing of developmental events, and the possible existence of distinct larval morphs for this species. Utilizing data collected over four consecutive years from various locations, we described the development, growth, and larval morphology using both linear and geometric morphometrics during the pre‐ and prometamorphic stages. Our aim was to comprehend how anuran larvae in predictable environments synchronize the timing of their phenotypic transformations with external conditions. We identified two distinct cohorts: spring–summer and autumn–spring, each exhibiting distinct rates of growth and development until metamorphosis, resulting in size discrepancies. Moreover, the physical attributes of the breeding sites influenced the size of the tadpoles. However, the observed variation in shape was not related to the ontogenetic period, cohort, or developmental site. Ultimately, the observed variations had no impact on the morphology at metamorphosis. The comprehensive data gathered from our observations in B. cordobae yield valuable insights that contribute to a deeper comprehension of anuran larval development under natural conditions where changes are predictable and follow a regular pattern throughout the year, ultimately maximizing reproductive success.
{"title":"Living in a predictable environment: Intraspecific variation in tadpole size and shape of the Sierra's treefrog","authors":"A. Bonino, J. Lescano, J. Goldberg, S. I. Quinzio","doi":"10.1111/jzo.13201","DOIUrl":"https://doi.org/10.1111/jzo.13201","url":null,"abstract":"Within the breeding sites of anurans, factors at the microhabitat scale can exhibit variations over the years, resulting in temporal fluctuations within these sites. These fluctuations may lead to modifications in “normal larval development” and observable phenotypic changes. These developmental alterations appear to have evolved as shared strategies for achieving reproductive success and ensuring the survival of offspring. In a population of <jats:italic>Boana cordobae</jats:italic> inhabiting the Central Pampean Sierras (Córdoba, Argentina), the coexistence of pre‐ and prometamorphic tadpoles throughout the year, coupled with variations in size and shape within the same developmental stage, has led us to question about the duration of the larval period, variations in the timing of developmental events, and the possible existence of distinct larval morphs for this species. Utilizing data collected over four consecutive years from various locations, we described the development, growth, and larval morphology using both linear and geometric morphometrics during the pre‐ and prometamorphic stages. Our aim was to comprehend how anuran larvae in predictable environments synchronize the timing of their phenotypic transformations with external conditions. We identified two distinct cohorts: <jats:italic>spring–summer</jats:italic> and <jats:italic>autumn–spring</jats:italic>, each exhibiting distinct rates of growth and development until metamorphosis, resulting in size discrepancies. Moreover, the physical attributes of the breeding sites influenced the size of the tadpoles. However, the observed variation in shape was not related to the ontogenetic period, cohort, or developmental site. Ultimately, the observed variations had no impact on the morphology at metamorphosis. The comprehensive data gathered from our observations in <jats:italic>B. cordobae</jats:italic> yield valuable insights that contribute to a deeper comprehension of anuran larval development under natural conditions where changes are predictable and follow a regular pattern throughout the year, ultimately maximizing reproductive success.","PeriodicalId":17600,"journal":{"name":"Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141872947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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