Pub Date : 2022-07-29DOI: 10.22621/cfn.v136i1.2791
John Mager, Brooks Wade, Sherry Abts, J. Paruk
Little is known about the behaviour of Common Loon (Gavia immer) during the critical overwintering period, let alone the behaviour of the small, but increasing number of loons that overwinter on freshwater lakes in North America. We examined the diurnal time-activity budgets of Common Loon overwintering on a large reservoir in northwest South Carolina between 2018 and 2020. Similar to previous studies of breeding individuals and individuals that overwinter in marine waters, loons (n = 132) overwintering on this reservoir spent most of their time (52%) foraging. However, we found distinct differences in the activity budgets of individuals associated with their degree of sociality. Solitary birds (individuals spending 0–20% of time within 20 m of conspecifics) spent significantly more time foraging than did those that were either loosely-social (>20–<70% of time within 20 m of conspecifics) or strongly-social (70–100% of time). Although solitary loons made as many foraging dives as social birds, their dives were much longer, likely reflecting dives for larger predatory fish. In contrast, social individuals made much shorter, shallower dives, often foraging on shallower baitfish that they appear to pursue to the water surface and consume collectively. Such findings add to our understanding of loon winter behaviour and raise interesting questions regarding social behaviour and the short- and long-term trade-offs associated with social foraging in this species.
{"title":"Foraging patterns vary with the degree of sociality among Common Loon (Gavia immer) overwintering on a freshwater lake","authors":"John Mager, Brooks Wade, Sherry Abts, J. Paruk","doi":"10.22621/cfn.v136i1.2791","DOIUrl":"https://doi.org/10.22621/cfn.v136i1.2791","url":null,"abstract":"Little is known about the behaviour of Common Loon (Gavia immer) during the critical overwintering period, let alone the behaviour of the small, but increasing number of loons that overwinter on freshwater lakes in North America. We examined the diurnal time-activity budgets of Common Loon overwintering on a large reservoir in northwest South Carolina between 2018 and 2020. Similar to previous studies of breeding individuals and individuals that overwinter in marine waters, loons (n = 132) overwintering on this reservoir spent most of their time (52%) foraging. However, we found distinct differences in the activity budgets of individuals associated with their degree of sociality. Solitary birds (individuals spending 0–20% of time within 20 m of conspecifics) spent significantly more time foraging than did those that were either loosely-social (>20–<70% of time within 20 m of conspecifics) or strongly-social (70–100% of time). Although solitary loons made as many foraging dives as social birds, their dives were much longer, likely reflecting dives for larger predatory fish. In contrast, social individuals made much shorter, shallower dives, often foraging on shallower baitfish that they appear to pursue to the water surface and consume collectively. Such findings add to our understanding of loon winter behaviour and raise interesting questions regarding social behaviour and the short- and long-term trade-offs associated with social foraging in this species.","PeriodicalId":56136,"journal":{"name":"The Canadian Field-Naturalist","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75073825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-29DOI: 10.22621/cfn.v136i1.2951
P. Catling, Sheila Kuja, E. Haber, John Riley, K. Lindsay, Ron Thorpe
{"title":"A tribute to James Edwin Cruise, Ph.D., L.L.D., 1925–2021","authors":"P. Catling, Sheila Kuja, E. Haber, John Riley, K. Lindsay, Ron Thorpe","doi":"10.22621/cfn.v136i1.2951","DOIUrl":"https://doi.org/10.22621/cfn.v136i1.2951","url":null,"abstract":"","PeriodicalId":56136,"journal":{"name":"The Canadian Field-Naturalist","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74005329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-29DOI: 10.22621/cfn.v136i1.2877
Brandon Edwards, A. Binley, Willow B. English, E. Hudgins, Samuel Snow
Red-winged Blackbird (Agelaius phoeniceus) is a highly vocal species with a repertoire of similar, yet acoustically distinct songs. These songs may be altered drastically if, as a nestling, the male goes deaf or becomes acoustically isolated. In deaf Red-winged Blackbirds, these dramatic song alterations may present as songs bearing slight resemblance to the introductory phrase of their normal song. Here, we present a Red-winged Blackbird song observed in Ottawa, Ontario, Canada, that is far outside any normal variation in Red-winged Blackbird songs. Given the individual’s age and the consistency of the anomalous song, it is possible that this is a deaf bird.
{"title":"A highly anomalous Red-winged Blackbird (Agelaius phoeniceus) song","authors":"Brandon Edwards, A. Binley, Willow B. English, E. Hudgins, Samuel Snow","doi":"10.22621/cfn.v136i1.2877","DOIUrl":"https://doi.org/10.22621/cfn.v136i1.2877","url":null,"abstract":"Red-winged Blackbird (Agelaius phoeniceus) is a highly vocal species with a repertoire of similar, yet acoustically distinct songs. These songs may be altered drastically if, as a nestling, the male goes deaf or becomes acoustically isolated. In deaf Red-winged Blackbirds, these dramatic song alterations may present as songs bearing slight resemblance to the introductory phrase of their normal song. Here, we present a Red-winged Blackbird song observed in Ottawa, Ontario, Canada, that is far outside any normal variation in Red-winged Blackbird songs. Given the individual’s age and the consistency of the anomalous song, it is possible that this is a deaf bird.","PeriodicalId":56136,"journal":{"name":"The Canadian Field-Naturalist","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72655322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-29DOI: 10.22621/cfn.v136i1.2769
T. Jung
Canada Lynx (Lynx canadensis) is a specialist predator of Snowshoe Hare (Lepus americanus), which dominates its diet. However, hare populations cycle over 9–11 years, and many lynx disperse or starve during cyclic lows of their prey. Here, I report observations of Canada Lynx scavenging and attempting to prey on Common Raven (Corvus corax). In addition, I provide a brief review of birds as a food item of lynx. These are the first observations of ravens as a food source for lynx and may be a response to lynx being malnourished. The value of these observations is that they highlight the adaptability of some lynx to opportunistically use novel prey species during the decline phase of cyclic Snowshoe Hare.
{"title":"Raven (Corvus corax) as a novel food item for lynx (Lynx canadensis)","authors":"T. Jung","doi":"10.22621/cfn.v136i1.2769","DOIUrl":"https://doi.org/10.22621/cfn.v136i1.2769","url":null,"abstract":"Canada Lynx (Lynx canadensis) is a specialist predator of Snowshoe Hare (Lepus americanus), which dominates its diet. However, hare populations cycle over 9–11 years, and many lynx disperse or starve during cyclic lows of their prey. Here, I report observations of Canada Lynx scavenging and attempting to prey on Common Raven (Corvus corax). In addition, I provide a brief review of birds as a food item of lynx. These are the first observations of ravens as a food source for lynx and may be a response to lynx being malnourished. The value of these observations is that they highlight the adaptability of some lynx to opportunistically use novel prey species during the decline phase of cyclic Snowshoe Hare.","PeriodicalId":56136,"journal":{"name":"The Canadian Field-Naturalist","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82184488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-29DOI: 10.22621/cfn.v136i1.2811
J. Baxter‐Gilbert, Lorne King, J. Riley
The island of Newfoundland has no native amphibian taxa, although six species of Anura (i.e., frogs and toads) have been introduced since European colonisation, four of which have established self-sustaining populations. Here, we document Eastern Red-backed Salamander (Plethodon cinereus) on Newfoundland for the first time, in what appears to be a self-sustaining population near Conception Bay South. This is the first species of Caudata (i.e., newts and salamanders) to have been introduced to the island, as well as the first occurrence of Eastern Red-backed Salamander establishing a population outside its native range. The impact that this non-native species might have on forest ecosystems on Newfoundland is unclear and further study is required to determine whether eradication of the species from Newfoundland is necessary or feasible.
{"title":"First report of Eastern Red-backed Salamander (Plethodon cinereus) on Newfoundland","authors":"J. Baxter‐Gilbert, Lorne King, J. Riley","doi":"10.22621/cfn.v136i1.2811","DOIUrl":"https://doi.org/10.22621/cfn.v136i1.2811","url":null,"abstract":"The island of Newfoundland has no native amphibian taxa, although six species of Anura (i.e., frogs and toads) have been introduced since European colonisation, four of which have established self-sustaining populations. Here, we document Eastern Red-backed Salamander (Plethodon cinereus) on Newfoundland for the first time, in what appears to be a self-sustaining population near Conception Bay South. This is the first species of Caudata (i.e., newts and salamanders) to have been introduced to the island, as well as the first occurrence of Eastern Red-backed Salamander establishing a population outside its native range. The impact that this non-native species might have on forest ecosystems on Newfoundland is unclear and further study is required to determine whether eradication of the species from Newfoundland is necessary or feasible.","PeriodicalId":56136,"journal":{"name":"The Canadian Field-Naturalist","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88213477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-29DOI: 10.22621/cfn.v136i1.2573
C. Schmidt, Jason R. Treberg, R. Kinnunen, C. Garroway
Urban wildlife populations experience human-driven environmental changes that can be both beneficial and detrimental to individual health. We measured body condition and serum chemistry (electrolyte levels, markers of kidney and liver function, protein, glucose, and cholesterol) in a native urban and rural population of Eastern Gray Squirrel (Sciurus carolinensis) to assess whether we could detect physiological responses to environmental stressors or dietary differences. We found no differences in body condition between habitats and no evidence of malnutrition at either site. However, urban squirrels had higher blood glucose, lower potassium, phosphorus, chloride, and albumin:globulin ratios. These results align with previous findings of increased dietary sugar in cities and suggest that urban populations of gray squirrels are under greater environmental stress than rural populations, providing future directions for studying physiological responses to urbanization.
{"title":"Serum biochemistry suggests a physiological response to environmental stress in a native urban Eastern Gray Squirrel (Sciurus carolinensis) population","authors":"C. Schmidt, Jason R. Treberg, R. Kinnunen, C. Garroway","doi":"10.22621/cfn.v136i1.2573","DOIUrl":"https://doi.org/10.22621/cfn.v136i1.2573","url":null,"abstract":"Urban wildlife populations experience human-driven environmental changes that can be both beneficial and detrimental to individual health. We measured body condition and serum chemistry (electrolyte levels, markers of kidney and liver function, protein, glucose, and cholesterol) in a native urban and rural population of Eastern Gray Squirrel (Sciurus carolinensis) to assess whether we could detect physiological responses to environmental stressors or dietary differences. We found no differences in body condition between habitats and no evidence of malnutrition at either site. However, urban squirrels had higher blood glucose, lower potassium, phosphorus, chloride, and albumin:globulin ratios. These results align with previous findings of increased dietary sugar in cities and suggest that urban populations of gray squirrels are under greater environmental stress than rural populations, providing future directions for studying physiological responses to urbanization.","PeriodicalId":56136,"journal":{"name":"The Canadian Field-Naturalist","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84377323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-29DOI: 10.22621/cfn.v136i1.3023
Robin Collins
{"title":"\"A Trillion Trees: Restoring Our Forests by Trusting in Nature\" by Fred Pearce, 2022. [book review]","authors":"Robin Collins","doi":"10.22621/cfn.v136i1.3023","DOIUrl":"https://doi.org/10.22621/cfn.v136i1.3023","url":null,"abstract":"","PeriodicalId":56136,"journal":{"name":"The Canadian Field-Naturalist","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88464235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-29DOI: 10.22621/cfn.v136i1.2861
Nicholas B Sakich
Wing-assisted incline running (WAIR) has been observed in bird taxa from multiple clades. Its wide phylogenetic distribution in modern birds suggests that it is an ancestral trait for class Aves. WAIR as a behaviour is speculated to predate the evolution of full-powered flight, and to have formed a behavioural and physiological stepping stone between terrestrial and aerial life. Here I report an observation of apparent WAIR in a Common Grackle (Quiscalus quiscula) photographed incidentally on a trail camera deployed in an urban backyard in Guelph, Ontario, Canada. To my knowledge this is the first documented observation of apparent WAIR for the family Icteridae. Furthermore, it highlights the value of non-systematic use of trail cameras for making unique natural history observations.
{"title":"Apparent wing-assisted incline running in a Common Grackle (Quiscalus quiscula)","authors":"Nicholas B Sakich","doi":"10.22621/cfn.v136i1.2861","DOIUrl":"https://doi.org/10.22621/cfn.v136i1.2861","url":null,"abstract":"Wing-assisted incline running (WAIR) has been observed in bird taxa from multiple clades. Its wide phylogenetic distribution in modern birds suggests that it is an ancestral trait for class Aves. WAIR as a behaviour is speculated to predate the evolution of full-powered flight, and to have formed a behavioural and physiological stepping stone between terrestrial and aerial life. Here I report an observation of apparent WAIR in a Common Grackle (Quiscalus quiscula) photographed incidentally on a trail camera deployed in an urban backyard in Guelph, Ontario, Canada. To my knowledge this is the first documented observation of apparent WAIR for the family Icteridae. Furthermore, it highlights the value of non-systematic use of trail cameras for making unique natural history observations.","PeriodicalId":56136,"journal":{"name":"The Canadian Field-Naturalist","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86661671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-04-28DOI: 10.22621/cfn.v135i4.2947
J. Way
{"title":"\"Wolves: Western Warriors\" by Julie Argyle, 2022 [book review]","authors":"J. Way","doi":"10.22621/cfn.v135i4.2947","DOIUrl":"https://doi.org/10.22621/cfn.v135i4.2947","url":null,"abstract":"","PeriodicalId":56136,"journal":{"name":"The Canadian Field-Naturalist","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87543243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-04-28DOI: 10.22621/cfn.v135i4.2973
D. Lepitzki
{"title":"The Canadian Field-Naturalist welcomes our new Book Review Editor","authors":"D. Lepitzki","doi":"10.22621/cfn.v135i4.2973","DOIUrl":"https://doi.org/10.22621/cfn.v135i4.2973","url":null,"abstract":"","PeriodicalId":56136,"journal":{"name":"The Canadian Field-Naturalist","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84777357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","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：