John M. Green, Dustin Schornagel, Khanh Nguyen, Curtis Pennell, Corey Morris
Atlantic cod (Gadus morhua Linnaeus, 1758) can experience mortality at sub-zero (<0°C) temperatures in ice-infested waters, and many populations migrate to deeper and warmer areas during winter. An exception is the resident population in Gilbert Bay, Labrador, which annually experiences six months of sub-zero temperatures. We used the VEMCO Positioning System (VPS) to estimate fish locations to determine depth utilization, and seasonal movements of tagged Gilbert Bay cod ranging in size from 43 to 75 cm. This is the first study to directly monitor the movements of adult Atlantic cod for extended periods (months) in sub-zero temperatures. Gilbert Bay cod remained active under an ice-covered surface during the six months of sub-zero temperatures. During both warm (>0°C) and cold (≤0°C) periods, fish spent similar amounts of time not moving, moving slowly, and moving at medium and fast rates. They tended to utilize shallow depths, <10 m, beneath surface ice during winter, while utilizing deeper depths as well during other times of the year. Surprisingly, fish that resided within our tracking array year-round had greater cumulative swimming distances during sub-zero periods compared to warmer periods. No tracked fish died during winter further highlighting the cold-adaptiveness of this population, and its importance to biodiversity conservation.
{"title":"Field observations of the movements of locally adapted Atlantic cod (Gadus morhua) living in zero and sub-zero centigrade temperatures for half the year","authors":"John M. Green, Dustin Schornagel, Khanh Nguyen, Curtis Pennell, Corey Morris","doi":"10.1139/cjz-2023-0067","DOIUrl":"https://doi.org/10.1139/cjz-2023-0067","url":null,"abstract":"Atlantic cod (Gadus morhua Linnaeus, 1758) can experience mortality at sub-zero (<0°C) temperatures in ice-infested waters, and many populations migrate to deeper and warmer areas during winter. An exception is the resident population in Gilbert Bay, Labrador, which annually experiences six months of sub-zero temperatures. We used the VEMCO Positioning System (VPS) to estimate fish locations to determine depth utilization, and seasonal movements of tagged Gilbert Bay cod ranging in size from 43 to 75 cm. This is the first study to directly monitor the movements of adult Atlantic cod for extended periods (months) in sub-zero temperatures. Gilbert Bay cod remained active under an ice-covered surface during the six months of sub-zero temperatures. During both warm (>0°C) and cold (≤0°C) periods, fish spent similar amounts of time not moving, moving slowly, and moving at medium and fast rates. They tended to utilize shallow depths, <10 m, beneath surface ice during winter, while utilizing deeper depths as well during other times of the year. Surprisingly, fish that resided within our tracking array year-round had greater cumulative swimming distances during sub-zero periods compared to warmer periods. No tracked fish died during winter further highlighting the cold-adaptiveness of this population, and its importance to biodiversity conservation.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135385676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Emily Wright, Jacob Bayouth, Joseph Bayouth, Asha Worsham, Grant McDaniel, Tess Hollinger, Vivienne Lacy, Emma Johnston, David Pipkin, Emma Roberts, Robert D. Bradley
Introgressive hybridization between members of Odocoileus was examined using the mitochondrial cytochrome-b (maternal marker) and paternal sex-determining region Y ( Sry) genes. Eight out of 130 free-ranging individuals from the Panhandle and Trans-Pecos regions of Texas were determined to possess the mitochondrial haplotype of mule deer ( Odocoileus hemionus (Rafinesque, 1817)) and the paternal haplotype of white-tailed deer ( Odocoileus virginianus Rafinesque, 1832). Results indicated that hybridization between deer species in Texas (6.15%) was more broadly distributed than previously reported. Previous studies demonstrated that ancient hybridization events (1.32 mya) involved the capture of the white-tailed deer mitochondrial genome by mule deer, indicating a male mule deer × a female white-tailed deer directionality relevant to hybridization. Alternatively, contemporary hybridization events indicated a reversal in directionality and suggested a cross between a female mule deer × a male white-tailed deer. The Sry gene and species assignment based on morphological characters consistently were in agreement. Further, phylogenetic relationships between Odocoileus virginianus couesi and Odocoileus hemionus eremicus warrant additional investigation as recent hybridization (>200 years) may be a mechanism that allowed these two subspecies to evolve a unique evolutionary trajectory.
{"title":"Contemporary hybridization between female mule deer and male white-tailed deer in west Texas differs from the hypothesized sex mating patterns recovered from ancient hybridization events","authors":"Emily Wright, Jacob Bayouth, Joseph Bayouth, Asha Worsham, Grant McDaniel, Tess Hollinger, Vivienne Lacy, Emma Johnston, David Pipkin, Emma Roberts, Robert D. Bradley","doi":"10.1139/cjz-2023-0082","DOIUrl":"https://doi.org/10.1139/cjz-2023-0082","url":null,"abstract":"Introgressive hybridization between members of Odocoileus was examined using the mitochondrial cytochrome-b (maternal marker) and paternal sex-determining region Y ( Sry) genes. Eight out of 130 free-ranging individuals from the Panhandle and Trans-Pecos regions of Texas were determined to possess the mitochondrial haplotype of mule deer ( Odocoileus hemionus (Rafinesque, 1817)) and the paternal haplotype of white-tailed deer ( Odocoileus virginianus Rafinesque, 1832). Results indicated that hybridization between deer species in Texas (6.15%) was more broadly distributed than previously reported. Previous studies demonstrated that ancient hybridization events (1.32 mya) involved the capture of the white-tailed deer mitochondrial genome by mule deer, indicating a male mule deer × a female white-tailed deer directionality relevant to hybridization. Alternatively, contemporary hybridization events indicated a reversal in directionality and suggested a cross between a female mule deer × a male white-tailed deer. The Sry gene and species assignment based on morphological characters consistently were in agreement. Further, phylogenetic relationships between Odocoileus virginianus couesi and Odocoileus hemionus eremicus warrant additional investigation as recent hybridization (>200 years) may be a mechanism that allowed these two subspecies to evolve a unique evolutionary trajectory.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135535169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Travis Durhack, Melanie Aminot, Jason Treberg, Eva Enders
Understanding how metabolic costs change in relation to increasing temperature under future climate changes is important to predict how ectotherms will be affected across the globe. In fish, whole body respiration is traditionally used to estimate aerobic performance via an organism’s minimum and maximum oxygen consumption rates. However, mitochondria play a crucial role in the aerobic cascade and may be a useful surrogate of aerobic performance. To test whether whole body oxygen consumption and mitochondrial capacity are correlated, we estimated whole body metabolic and mitochondrial respiration rates (using permeabilized red muscle fibres) in brook trout ( Salvelinus fontinalis (Mitchill, 1814)) at 10, 15, and 20 °C. Standard metabolic rate increased with acclimation temperature, while maximum rates were less sensitive. All mitochondrial respiration rates increased with acclimation temperature, suggesting that red muscle mitochondrial preparations may correlate to the minimal metabolic demands in this species. When expressed as relative rates of electron flow, the red muscle fibres showed no effect of temperature on mitochondrial coupling efficiency. However, there was a pattern of declining capacity to augment respiration via complex II with increasing temperature with a concomitant increase in the capacity of the phosphorylating system relative to maximal rates of mitochondrial electron flow.
{"title":"Comparing whole body and red muscle mitochondrial respiration in an active teleost fish, Brook Trout (Salvelinus fontinalis)","authors":"Travis Durhack, Melanie Aminot, Jason Treberg, Eva Enders","doi":"10.1139/cjz-2023-0045","DOIUrl":"https://doi.org/10.1139/cjz-2023-0045","url":null,"abstract":"Understanding how metabolic costs change in relation to increasing temperature under future climate changes is important to predict how ectotherms will be affected across the globe. In fish, whole body respiration is traditionally used to estimate aerobic performance via an organism’s minimum and maximum oxygen consumption rates. However, mitochondria play a crucial role in the aerobic cascade and may be a useful surrogate of aerobic performance. To test whether whole body oxygen consumption and mitochondrial capacity are correlated, we estimated whole body metabolic and mitochondrial respiration rates (using permeabilized red muscle fibres) in brook trout ( Salvelinus fontinalis (Mitchill, 1814)) at 10, 15, and 20 °C. Standard metabolic rate increased with acclimation temperature, while maximum rates were less sensitive. All mitochondrial respiration rates increased with acclimation temperature, suggesting that red muscle mitochondrial preparations may correlate to the minimal metabolic demands in this species. When expressed as relative rates of electron flow, the red muscle fibres showed no effect of temperature on mitochondrial coupling efficiency. However, there was a pattern of declining capacity to augment respiration via complex II with increasing temperature with a concomitant increase in the capacity of the phosphorylating system relative to maximal rates of mitochondrial electron flow.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135534634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Stephen Dobson, Claire Saraux, Vincent A. Viblanc
Phenotypic plasticity of life-history traits is well known among vertebrate species. We estimated reproductive and somatic efforts of female Columbian ground squirrels ( Urocitellus columbianus (Ord, 1815)) to test for plasticity of these important resource allocations. We examined a 27-year dataset of life-history traits on these long-living (8–10 years), hibernating, montane-living mammals. Environmental variation was estimated from two important traits of mothers, their relative timing of breeding and spring maternal body mass (initial “capital” for use in subsequent reproduction). Results from 183 known-aged mothers and 508 litters revealed considerable variation in the relative timing of breeding, initial maternal mass, and reproductive and somatic efforts, as well as significant variation among ages and years. Results from 125 mothers that reproduced more than once (and 450 litters) revealed significant plasticity of reproductive and somatic efforts with respect to relative timing of breeding and spring maternal mass. A within-subject centering statistical approach showed that phenotypically plastic reproductive and somatic efforts were due to variation within individuals, but were not always reflected by the pattern of responses among individuals in the population. The plastic responses of different mothers appeared to be similar in strength.
{"title":"PHENOTYPIC PLASTICITY IN REPRODUCTIVE AND SOMATIC EFFORTS OF FEMALE COLUMBIAN GROUND SQUIRRELS","authors":"F. Stephen Dobson, Claire Saraux, Vincent A. Viblanc","doi":"10.1139/cjz-2023-0108","DOIUrl":"https://doi.org/10.1139/cjz-2023-0108","url":null,"abstract":"Phenotypic plasticity of life-history traits is well known among vertebrate species. We estimated reproductive and somatic efforts of female Columbian ground squirrels ( Urocitellus columbianus (Ord, 1815)) to test for plasticity of these important resource allocations. We examined a 27-year dataset of life-history traits on these long-living (8–10 years), hibernating, montane-living mammals. Environmental variation was estimated from two important traits of mothers, their relative timing of breeding and spring maternal body mass (initial “capital” for use in subsequent reproduction). Results from 183 known-aged mothers and 508 litters revealed considerable variation in the relative timing of breeding, initial maternal mass, and reproductive and somatic efforts, as well as significant variation among ages and years. Results from 125 mothers that reproduced more than once (and 450 litters) revealed significant plasticity of reproductive and somatic efforts with respect to relative timing of breeding and spring maternal mass. A within-subject centering statistical approach showed that phenotypically plastic reproductive and somatic efforts were due to variation within individuals, but were not always reflected by the pattern of responses among individuals in the population. The plastic responses of different mothers appeared to be similar in strength.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135534946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jacob L. Seguin, Melanie R. Boudreau, Sophia Lavergne, Ryan Lamoureux, Charles J. Krebs, Rudy Boonstra
Perceived predation risk alters prey behaviour and physiology, but few studies have examined downstream consequences on prey demography in wild populations. Perceived predation risk could alter adult reproductive performance via reduced investment in offspring quality and post-birth care. We manipulated perceived predation risk in snowshoe hare ( Lepus americanus Erxleben, 1777) by exposing pregnant mothers to chases by a domestic dog ( Canis familiaris Linnaeus, 1758). Litter size was comparable between risk-augmented and control groups, but treated females had more stillbirths and gave birth to leverets of lower body condition. Leverets from risk-augmented females had 88% higher 40-day mortality rate. Maternally preventable causes of death like starvation or predation by red squirrel ( Tamiasciurus hudsonicus (Erxleben, 1777)) caused this difference, particularly during the nursing period. Risk-augmented mothers were always more active than controls, but the difference was greatest during the nursing period. We found that perceived predation risk reduces maternal productivity pre- and post-partum, implying downstream consequences to populations. Because our treatment ended before parturition, we can link offspring performance such as survival and behaviour specifically to maternal life-history trade-offs, which has not been shown in a wild mammal.
感知到的捕食风险会改变猎物的行为和生理，但很少有研究调查野生种群对猎物数量的下游影响。感知到的捕食风险可以通过减少对后代质量和产后护理的投资来改变成人的生殖表现。我们通过将怀孕的雪鞋兔暴露于家犬(Canis familiaris Linnaeus, 1758)的追逐中，来操纵雪鞋兔(Lepus americanus Erxleben, 1777)的感知捕食风险。产仔数在风险增加组和对照组之间是相当的，但治疗过的雌性有更多的死产，产下的小白鼠身体状况较低。来自风险增强雌性的小杠杆40天死亡率高出88%。母亲可预防的死亡原因，如饥饿或被红松鼠(Tamiasciurus hudsonicus (Erxleben, 1777))捕食造成了这种差异，特别是在哺乳期。风险增加的母亲总是比对照组更活跃，但在哺乳期间差异最大。我们发现，感知到的捕食风险降低了产前和产后的孕产妇生产力，这意味着对种群的下游后果。因为我们的治疗在分娩前就结束了，我们可以将后代的表现，如生存和行为，具体地与母亲的生活史权衡联系起来，这在野生哺乳动物中还没有显示出来。
{"title":"Experimental manipulation of perceived predation risk alters survival, cause of death, and demographic patterns in juvenile snowshoe hares","authors":"Jacob L. Seguin, Melanie R. Boudreau, Sophia Lavergne, Ryan Lamoureux, Charles J. Krebs, Rudy Boonstra","doi":"10.1139/cjz-2023-0046","DOIUrl":"https://doi.org/10.1139/cjz-2023-0046","url":null,"abstract":"Perceived predation risk alters prey behaviour and physiology, but few studies have examined downstream consequences on prey demography in wild populations. Perceived predation risk could alter adult reproductive performance via reduced investment in offspring quality and post-birth care. We manipulated perceived predation risk in snowshoe hare ( Lepus americanus Erxleben, 1777) by exposing pregnant mothers to chases by a domestic dog ( Canis familiaris Linnaeus, 1758). Litter size was comparable between risk-augmented and control groups, but treated females had more stillbirths and gave birth to leverets of lower body condition. Leverets from risk-augmented females had 88% higher 40-day mortality rate. Maternally preventable causes of death like starvation or predation by red squirrel ( Tamiasciurus hudsonicus (Erxleben, 1777)) caused this difference, particularly during the nursing period. Risk-augmented mothers were always more active than controls, but the difference was greatest during the nursing period. We found that perceived predation risk reduces maternal productivity pre- and post-partum, implying downstream consequences to populations. Because our treatment ended before parturition, we can link offspring performance such as survival and behaviour specifically to maternal life-history trade-offs, which has not been shown in a wild mammal.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134886639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Dinn, Bruce Ott, Mariève Bouchard Marmen, Royce Steeves, Geneviève Côté, Vonda Hayes, C. Nozères, Meredith V. Everett, Abigail Powell, Jackson W.F. Chu
Mycale ( Mycale) loveni (Fristedt, 1887) is a very large structure-forming sponge that has previously been reported in the North Pacific, North Atlantic, and Arctic oceans. Through morphological and molecular examination, North Atlantic and Eastern Canadian Arctic specimens are now described as a new species, Mycale ( Mycale) lorea sp. nov. The two species have similar external morphology; however, the spicules that make up their skeletons differ in size and shape, and the species are also separated phylogenetically by multiple genetic markers.
{"title":"Two large structure-forming sponges from opposite North American coasts: a taxonomic review of Arctic–Pacific Mycale (Mycale) loveni and the description of a new Arctic–Atlantic Mycale","authors":"C. Dinn, Bruce Ott, Mariève Bouchard Marmen, Royce Steeves, Geneviève Côté, Vonda Hayes, C. Nozères, Meredith V. Everett, Abigail Powell, Jackson W.F. Chu","doi":"10.1139/cjz-2023-0011","DOIUrl":"https://doi.org/10.1139/cjz-2023-0011","url":null,"abstract":"Mycale ( Mycale) loveni (Fristedt, 1887) is a very large structure-forming sponge that has previously been reported in the North Pacific, North Atlantic, and Arctic oceans. Through morphological and molecular examination, North Atlantic and Eastern Canadian Arctic specimens are now described as a new species, Mycale ( Mycale) lorea sp. nov. The two species have similar external morphology; however, the spicules that make up their skeletons differ in size and shape, and the species are also separated phylogenetically by multiple genetic markers.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45275781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The willistoni group of Drosophila is subdivided into the alagitans, bocainensis and willistoni subgroups, and has been an important model for studying evolutionary processes in the Neotropics for decades. Phylogenetic studies place the bocainensis subgroup as a grade in relation to the monophyletic willistoni subgroup, although these included molecular or morphological data for up to four species of the 12 species included in the first subgroup. Here, we characterized the first nucleotide sequences for three mitochondrial and five nuclear genes of Drosophila bocainensis Pavan & da Cunha, 1947, and employed these for addressing the paraphyly of this subgroup under a coalescent approach. Our results still recovered this paraphyletic relationship, placing D. bocainensis, D. capricorni Dobzhansky & Pavan, 1943 and D. sucinea Patterson & Mainland, 1944 in a basal clade, which diverged around 6.81 million years ago. The relationship of D. nebulosa Sturtevant, 1916 and D. fumipennis Duda, 1925 as a sister clade to the willistoni subgroup was recovered. The possible causes of such paraphyly are discussed.
{"title":"Phylogenetic position of Drosophila bocainensis (Diptera, Drosophilidae) in the willistoni group and the paraphyletic status of the bocainensis subgroup","authors":"Henrique R.M. Antoniolli, M. Deprá, V. Valente","doi":"10.1139/cjz-2023-0054","DOIUrl":"https://doi.org/10.1139/cjz-2023-0054","url":null,"abstract":"The willistoni group of Drosophila is subdivided into the alagitans, bocainensis and willistoni subgroups, and has been an important model for studying evolutionary processes in the Neotropics for decades. Phylogenetic studies place the bocainensis subgroup as a grade in relation to the monophyletic willistoni subgroup, although these included molecular or morphological data for up to four species of the 12 species included in the first subgroup. Here, we characterized the first nucleotide sequences for three mitochondrial and five nuclear genes of Drosophila bocainensis Pavan & da Cunha, 1947, and employed these for addressing the paraphyly of this subgroup under a coalescent approach. Our results still recovered this paraphyletic relationship, placing D. bocainensis, D. capricorni Dobzhansky & Pavan, 1943 and D. sucinea Patterson & Mainland, 1944 in a basal clade, which diverged around 6.81 million years ago. The relationship of D. nebulosa Sturtevant, 1916 and D. fumipennis Duda, 1925 as a sister clade to the willistoni subgroup was recovered. The possible causes of such paraphyly are discussed.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47207898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Animal distributions continue to undergo dramatic shifts in response to environmental change as many ecosystems become altered or transition away from their historic states. The North American Great Plains was historically a vast prairie ecosystem that has been heavily altered into a patchwork of remnant grasslands, industrial agriculture and tracts invaded by woody vegetation. We studied the habitat selection of a forest-dwelling bird, the American woodcock (Scolopax minor Gmelin, 1789), at the westward periphery of the species’ range to determine how this species uses resources in this modified landscape. During the migratory and breeding season (March – May), woodcock tracked using GPS transmitters in Nebraska selected areas with higher proportions of young forest and forests with moist soils, exhibiting similar selection to birds occupying core areas of their range in eastern North America. During the summer, woodcock routinely used (46% of diurnal points) irrigated agricultural fields during the day, which was unexpected for a species that is known to summer in forest-dominated ecosystems. Our study provides evidence for flexible and atypical woodcock habitat selection at the edge of their range. These results add to the growing body of evidence pointing to regional shifts in avian community structure and further underscore the threats of agricultural conversion and woody encroachment to the Great Plains.
随着许多生态系统发生变化或从其历史状态转变，动物分布继续发生巨大变化，以应对环境变化。北美大平原在历史上是一个巨大的草原生态系统，已被严重改变为残余草原、工业农业和被木本植被入侵的大片土地的拼凑。我们研究了一种居住在森林中的鸟类——美国山鸡（Scolopax minor Gmelin，1789）在该物种范围的西部边缘的栖息地选择，以确定该物种如何在这种改良的景观中利用资源。在迁徙和繁殖季节（3月至5月），woodcock在内布拉斯加州使用GPS发射机进行跟踪，选择了幼林比例较高的地区和土壤湿润的森林，表现出与北美东部占据其活动范围核心区域的鸟类相似的选择。在夏季，woodcock通常在白天使用（46%的日间点）灌溉农田，这对于一个已知在森林主导的生态系统中避暑的物种来说是出乎意料的。我们的研究为在其范围边缘灵活和非典型的伍德科克栖息地选择提供了证据。这些结果增加了越来越多的证据，表明鸟类群落结构发生了区域性变化，并进一步强调了农业转型和木材侵占大平原的威胁。
{"title":"Industrial agricultural and woody encroachment associated with American Woodcock habitat selection in an altered grassland ecosystem","authors":"Stephen J. Brenner, J. Jorgensen","doi":"10.1139/cjz-2023-0123","DOIUrl":"https://doi.org/10.1139/cjz-2023-0123","url":null,"abstract":"Animal distributions continue to undergo dramatic shifts in response to environmental change as many ecosystems become altered or transition away from their historic states. The North American Great Plains was historically a vast prairie ecosystem that has been heavily altered into a patchwork of remnant grasslands, industrial agriculture and tracts invaded by woody vegetation. We studied the habitat selection of a forest-dwelling bird, the American woodcock (Scolopax minor Gmelin, 1789), at the westward periphery of the species’ range to determine how this species uses resources in this modified landscape. During the migratory and breeding season (March – May), woodcock tracked using GPS transmitters in Nebraska selected areas with higher proportions of young forest and forests with moist soils, exhibiting similar selection to birds occupying core areas of their range in eastern North America. During the summer, woodcock routinely used (46% of diurnal points) irrigated agricultural fields during the day, which was unexpected for a species that is known to summer in forest-dominated ecosystems. Our study provides evidence for flexible and atypical woodcock habitat selection at the edge of their range. These results add to the growing body of evidence pointing to regional shifts in avian community structure and further underscore the threats of agricultural conversion and woody encroachment to the Great Plains.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43350987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anthropogenic influences caused depletion and subsequent recovery of marine predators, but ecological consequences of altered predator abundance are not well-understood. Although many methods are used to study predator diets, methodological biases and logistical challenges preclude robust sampling schemes. We aimed to compare two non-invasive methods: metabarcoding scat-derived DNA and hard parts analysis of scat for the Northwest Atlantic grey seal (Halichoerus grypus (Fabricius, 1791)), a species that rebounded after near extirpation. We hypothesized metabarcoding would detect a greater diversity and frequency of prey, and that notable differences in diet will be detected since prior studies. Grey seal scat samples (N = 247) were collected between 2018¬-2019 from Monomoy Island, Massachusetts, USA. Metabarcoding detected greater prey richness on average, with more frequent detections of clupeids (Clupeidae) and flatfish (Pleuronectiformes) whereas hard parts analysis more frequently detected phycid hakes (Urophycis spp. Gill, 1863). Combining methods increased detections of 13 prey taxa, with 32 prey taxa identified overall. Skates (Rajidae), flatfish, clupeids, and sand lance (Ammodytes spp. Linnaeus, 1758) were top-occurring prey. Our study highlights the importance of using multiple methods to characterize generalist predator diets using non-invasive techniques and suggests grey seal diet has changed since the early 2000s.
{"title":"A comparative methodological approach to studying the diet of a recovering marine predator, the grey seal (Halichoerus grypus)","authors":"Christina M McCosker, Z. Olson, K. Ono","doi":"10.1139/cjz-2023-0104","DOIUrl":"https://doi.org/10.1139/cjz-2023-0104","url":null,"abstract":"Anthropogenic influences caused depletion and subsequent recovery of marine predators, but ecological consequences of altered predator abundance are not well-understood. Although many methods are used to study predator diets, methodological biases and logistical challenges preclude robust sampling schemes. We aimed to compare two non-invasive methods: metabarcoding scat-derived DNA and hard parts analysis of scat for the Northwest Atlantic grey seal (Halichoerus grypus (Fabricius, 1791)), a species that rebounded after near extirpation. We hypothesized metabarcoding would detect a greater diversity and frequency of prey, and that notable differences in diet will be detected since prior studies. Grey seal scat samples (N = 247) were collected between 2018¬-2019 from Monomoy Island, Massachusetts, USA. Metabarcoding detected greater prey richness on average, with more frequent detections of clupeids (Clupeidae) and flatfish (Pleuronectiformes) whereas hard parts analysis more frequently detected phycid hakes (Urophycis spp. Gill, 1863). Combining methods increased detections of 13 prey taxa, with 32 prey taxa identified overall. Skates (Rajidae), flatfish, clupeids, and sand lance (Ammodytes spp. Linnaeus, 1758) were top-occurring prey. Our study highlights the importance of using multiple methods to characterize generalist predator diets using non-invasive techniques and suggests grey seal diet has changed since the early 2000s.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48698323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Paulina Agata Idczak-Figiel, M. Ostrowski, A. Nowakowska
Snails are often exposed to high variability of ambient temperatures, thus in response to that, they function for prolonged periods in a dormant state. It is known that molecular chaperones (like HSPs) fulfill important functions in maintaining cell homeostasis and the cellular responses to stress and that they are activated in many different species upon exposition to various environmental stressors. HSPs defend organisms from the harmful consequences of heat shock and potentially alternative stressors too. After thorough consideration, we decided to identify proteins that interact with HSP70 and HSP90 in Helix pomatia Linnaeus, 1758 snails under extreme thermal (low and high) and photoperiod (short and long) conditions and at hypometabolic/active states as a response to environmental stress. Identification of proteins that interact with HSPs can define a new tool in molecular basis of adaptation to temperature stress in snails. After performing Co-immunoprecipitation and Western blot we obtained results showing that HSP70 interacts with hemocyanin alphaN and alphaD, and with other isoforms of hemocyanin - hemocyanin beta as well as with Na+/K+-ATPase, whereas HSP90 interacts with hemocyanin alphaN. It means that the chaperones are likely to affect the most important life-supporting systems of snails like respiration and ionic conductivity.
{"title":"The influence of environmental stressful conditions on the interaction between Heat Shock Proteins and chaperone-assisted proteins in land snails, Helix pomatia L.","authors":"Paulina Agata Idczak-Figiel, M. Ostrowski, A. Nowakowska","doi":"10.1139/cjz-2023-0118","DOIUrl":"https://doi.org/10.1139/cjz-2023-0118","url":null,"abstract":"Snails are often exposed to high variability of ambient temperatures, thus in response to that, they function for prolonged periods in a dormant state. It is known that molecular chaperones (like HSPs) fulfill important functions in maintaining cell homeostasis and the cellular responses to stress and that they are activated in many different species upon exposition to various environmental stressors. HSPs defend organisms from the harmful consequences of heat shock and potentially alternative stressors too. After thorough consideration, we decided to identify proteins that interact with HSP70 and HSP90 in Helix pomatia Linnaeus, 1758 snails under extreme thermal (low and high) and photoperiod (short and long) conditions and at hypometabolic/active states as a response to environmental stress. Identification of proteins that interact with HSPs can define a new tool in molecular basis of adaptation to temperature stress in snails. After performing Co-immunoprecipitation and Western blot we obtained results showing that HSP70 interacts with hemocyanin alphaN and alphaD, and with other isoforms of hemocyanin - hemocyanin beta as well as with Na+/K+-ATPase, whereas HSP90 interacts with hemocyanin alphaN. It means that the chaperones are likely to affect the most important life-supporting systems of snails like respiration and ionic conductivity.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42658879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：