Abstract - Caterpillars (Lepidoptera, Hymenoptera: Symphyta) are a critical food that breeding passerines use for raising young and serve as an important source of carotenoids that support nestling growth and feather pigmentation. When non-native, invasive plants grow abundant enough to reduce native plant diversity they can cause a reduction in caterpillar abundance. The goal of this study was to determine whether a reduction in caterpillars caused by non-native, invasive shrubs affects nestling health and/or the reproductive success of a shrubland-dependent passerine, Geothlypis trichas trichas (Common Yellowthroat). I first quantified caterpillar abundance on the dominant native and nonnative shrubs comprising Common Yellowthroat territories in shrubby transmission-line rights-of-way and estimated total caterpillar abundance in each territory based on the shrub species composition. I then determined if differences in shrub species composition and caterpillar abundance affected: (1) adult Common Yellowthroat reproductive success, (2) nestling Common Yellowthroat diet composition, or (3) nestling Common Yellowthroat growth rate, plasma carotenoids, and carotenoid-based plumage color. Nonnative, invasive shrubs did not reduce caterpillar abundance until they comprised ≥55% of the shrub volume and significantly reduced the diversity and abundance of native shrubs in bird territories. Differences in caterpillar abundance among sites did not result in differences in Common Yellowthroat productivity, but where non-native shrubs comprised ≥55% of the shrub volume, adults increased their frequency of feeding visits to nestlings and fed nestlings the greatest proportion of non-caterpillar prey. Daily surveys of shrubland bird presence/absence at study sites indicated that most shrubland-dependent bird species were absent where non-native shrubs comprised ≥55% of the shrub cover; such conditions likely equated to habitat loss for bird species less able than Common Yellowthroats to adapt to low shrub diversity and low caterpillar abundance.
{"title":"Effects of Non-Native Shrubs on Caterpillars and Shrubland-Dependent Passerines within Three Transmission Line Rights-of-Way in Southeastern New Hampshire","authors":"Matthew Tarr","doi":"10.1656/045.029.m2001","DOIUrl":"https://doi.org/10.1656/045.029.m2001","url":null,"abstract":"Abstract - Caterpillars (Lepidoptera, Hymenoptera: Symphyta) are a critical food that breeding passerines use for raising young and serve as an important source of carotenoids that support nestling growth and feather pigmentation. When non-native, invasive plants grow abundant enough to reduce native plant diversity they can cause a reduction in caterpillar abundance. The goal of this study was to determine whether a reduction in caterpillars caused by non-native, invasive shrubs affects nestling health and/or the reproductive success of a shrubland-dependent passerine, Geothlypis trichas trichas (Common Yellowthroat). I first quantified caterpillar abundance on the dominant native and nonnative shrubs comprising Common Yellowthroat territories in shrubby transmission-line rights-of-way and estimated total caterpillar abundance in each territory based on the shrub species composition. I then determined if differences in shrub species composition and caterpillar abundance affected: (1) adult Common Yellowthroat reproductive success, (2) nestling Common Yellowthroat diet composition, or (3) nestling Common Yellowthroat growth rate, plasma carotenoids, and carotenoid-based plumage color. Nonnative, invasive shrubs did not reduce caterpillar abundance until they comprised ≥55% of the shrub volume and significantly reduced the diversity and abundance of native shrubs in bird territories. Differences in caterpillar abundance among sites did not result in differences in Common Yellowthroat productivity, but where non-native shrubs comprised ≥55% of the shrub volume, adults increased their frequency of feeding visits to nestlings and fed nestlings the greatest proportion of non-caterpillar prey. Daily surveys of shrubland bird presence/absence at study sites indicated that most shrubland-dependent bird species were absent where non-native shrubs comprised ≥55% of the shrub cover; such conditions likely equated to habitat loss for bird species less able than Common Yellowthroats to adapt to low shrub diversity and low caterpillar abundance.","PeriodicalId":49742,"journal":{"name":"Northeastern Naturalist","volume":"29 1","pages":"1 - 43"},"PeriodicalIF":0.4,"publicationDate":"2022-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48969777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Petroelje, N. Fowler, E. K. Orning, B. Patterson, M. Romanski, J. Belant
Abstract Canis lupus (Gray Wolf or Wolf) have killed subordinate canids that scavenge on Wolf-killed prey, but little evidence is available for antagonistic behavior of Wolves toward other canids at interspecific den sites. We investigated clusters of locations from a global positioning system (GPS)collared male Wolf, translocated to Isle Royale National Park, MI, on 23 March 2019. On 17 May 2019, we investigated a GPS cluster of the Wolf and observed 3 Vulpes vulpes (Red Fox) kit carcasses at an excavated Red Fox den site. We report details from this event and evidence for interspecific aggression and implications for Wolf–Red Fox interactions. To our knowledge, this represents the first reported killing of Red Fox kits at their den by a Wolf. Limited reports of interspecific killings by Wolves of Red Foxes suggests this interaction was opportunistic and rare.
{"title":"Interspecific Killing of Vulpes vulpes (Red Fox) Kits at a Den Site by Canis lupus (Gray Wolf) in Isle Royale National Park, Michigan","authors":"T. Petroelje, N. Fowler, E. K. Orning, B. Patterson, M. Romanski, J. Belant","doi":"10.1656/045.029.0113","DOIUrl":"https://doi.org/10.1656/045.029.0113","url":null,"abstract":"Abstract Canis lupus (Gray Wolf or Wolf) have killed subordinate canids that scavenge on Wolf-killed prey, but little evidence is available for antagonistic behavior of Wolves toward other canids at interspecific den sites. We investigated clusters of locations from a global positioning system (GPS)collared male Wolf, translocated to Isle Royale National Park, MI, on 23 March 2019. On 17 May 2019, we investigated a GPS cluster of the Wolf and observed 3 Vulpes vulpes (Red Fox) kit carcasses at an excavated Red Fox den site. We report details from this event and evidence for interspecific aggression and implications for Wolf–Red Fox interactions. To our knowledge, this represents the first reported killing of Red Fox kits at their den by a Wolf. Limited reports of interspecific killings by Wolves of Red Foxes suggests this interaction was opportunistic and rare.","PeriodicalId":49742,"journal":{"name":"Northeastern Naturalist","volume":"29 1","pages":"N18 - N26"},"PeriodicalIF":0.4,"publicationDate":"2022-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47548607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. C. Magidow, A. DiTommaso, Anna S. Westbrook, Matthew J. Kwok, Q. Ketterings, L. Milbrath
Abstract Vincetoxicum nigrum (Black Swallow-wort) and V. rossicum (Pale Swallowwort) are non-native, perennial vines that are spreading across North America. We collected soil samples from invaded sites in the northeastern United States and southeastern Canada. We also performed GIS analyses using the site locations, locations from iMapInvasives, and soil data from SSURGO. We found that Black Swallow-wort tended to occupy Inceptisols while Pale Swallow-wort occupied soils with more silt and clay, including Alfisols. Mean soil pH was lower at Black Swallow-wort sites compared to Pale Swallow-wort sites. However, both species colonized soils that varied widely in pH, fertility, texture, and taxonomy. We conclude that abiotic soil characteristics do not strongly constrain swallow-wort distributions in North America.
{"title":"Soil Characteristics of North American Sites Colonized by the Non-Native, Invasive Vines Black Swallow-Wort and Pale Swallow-Wort","authors":"L. C. Magidow, A. DiTommaso, Anna S. Westbrook, Matthew J. Kwok, Q. Ketterings, L. Milbrath","doi":"10.1656/045.029.0111","DOIUrl":"https://doi.org/10.1656/045.029.0111","url":null,"abstract":"Abstract Vincetoxicum nigrum (Black Swallow-wort) and V. rossicum (Pale Swallowwort) are non-native, perennial vines that are spreading across North America. We collected soil samples from invaded sites in the northeastern United States and southeastern Canada. We also performed GIS analyses using the site locations, locations from iMapInvasives, and soil data from SSURGO. We found that Black Swallow-wort tended to occupy Inceptisols while Pale Swallow-wort occupied soils with more silt and clay, including Alfisols. Mean soil pH was lower at Black Swallow-wort sites compared to Pale Swallow-wort sites. However, both species colonized soils that varied widely in pH, fertility, texture, and taxonomy. We conclude that abiotic soil characteristics do not strongly constrain swallow-wort distributions in North America.","PeriodicalId":49742,"journal":{"name":"Northeastern Naturalist","volume":"29 1","pages":"108 - 132"},"PeriodicalIF":0.4,"publicationDate":"2022-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44501700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Chemical treatments are used to protect Tsuga canadensis (Eastern Hemlock) from Adelges tsugae (Hemlock Woolly Adelgid), yet little is known about how avian communities respond. We tested the efficacy of imidacloprid soil drenches on hemlocks and its impact on avian indicator species in the Appalachian Mountains of Kentucky at 65 sites (37 treated) in 2009 and 2018. Percent dead hemlock increased 11%, regardless of chemical treatment. Hemlock had higher vigor in treated sites, but a hemlock-decline index did not differ by treatment. None of 6 indicator bird species showed a significant population response to chemical treatments. Setophaga virens (Black-throated Green Warbler) declined between years across treated and untreated sites, whereas Contopus virens (Eastern Wood-Pewee) increased between years. Treatments positively affected individual hemlocks, but this did not carry over to influence avian species. Hemlock health may need to decline below some threshold before avian species respond.
{"title":"Abundance of Songbirds in Eastern Hemlock Stands Following Chemical Treatments for Hemlock Woolly Adelgid","authors":"Natalie M. Bekins, David R. Brown","doi":"10.1656/045.029.0112","DOIUrl":"https://doi.org/10.1656/045.029.0112","url":null,"abstract":"Abstract Chemical treatments are used to protect Tsuga canadensis (Eastern Hemlock) from Adelges tsugae (Hemlock Woolly Adelgid), yet little is known about how avian communities respond. We tested the efficacy of imidacloprid soil drenches on hemlocks and its impact on avian indicator species in the Appalachian Mountains of Kentucky at 65 sites (37 treated) in 2009 and 2018. Percent dead hemlock increased 11%, regardless of chemical treatment. Hemlock had higher vigor in treated sites, but a hemlock-decline index did not differ by treatment. None of 6 indicator bird species showed a significant population response to chemical treatments. Setophaga virens (Black-throated Green Warbler) declined between years across treated and untreated sites, whereas Contopus virens (Eastern Wood-Pewee) increased between years. Treatments positively affected individual hemlocks, but this did not carry over to influence avian species. Hemlock health may need to decline below some threshold before avian species respond.","PeriodicalId":49742,"journal":{"name":"Northeastern Naturalist","volume":"29 1","pages":"133 - 152"},"PeriodicalIF":0.4,"publicationDate":"2022-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48268819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract - Hirundo rustica (Barn Swallow) belongs to a suite of aerial insectivores that are showing serious population declines in northeastern North America. Various causes of these declines have been postulated, especially including agricultural intensification, declining insect populations, and/or increased mortality associated with climate changes. In this study, we examined foraging behavior of Barn Swallows nesting in a large breeding colony located in western Massachusetts. Swallows foraged primarily within 1 km of their nesting site. Most of the nearby agricultural areas used by foraging swallows were broadly characterized as pasture/hay or cultivated land uses; we found no significant difference in foraging activity levels between these habitat categories. In addition to the availability of suitable nesting structures, successful conservation of Barn Swallows likely requires that breeding colonies have access to nearby fields which provide foraging opportunities. Further study is needed to clarify specific habitat management that will enhance populations of flying insects preyed upon by swallows and other aerial insectivores.
{"title":"A Preliminary Study of Foraging Habitat Use by Nesting Barn Swallows in Massachusetts","authors":"J. Atwood, Marie Rhodes","doi":"10.1656/045.029.0109","DOIUrl":"https://doi.org/10.1656/045.029.0109","url":null,"abstract":"Abstract - Hirundo rustica (Barn Swallow) belongs to a suite of aerial insectivores that are showing serious population declines in northeastern North America. Various causes of these declines have been postulated, especially including agricultural intensification, declining insect populations, and/or increased mortality associated with climate changes. In this study, we examined foraging behavior of Barn Swallows nesting in a large breeding colony located in western Massachusetts. Swallows foraged primarily within 1 km of their nesting site. Most of the nearby agricultural areas used by foraging swallows were broadly characterized as pasture/hay or cultivated land uses; we found no significant difference in foraging activity levels between these habitat categories. In addition to the availability of suitable nesting structures, successful conservation of Barn Swallows likely requires that breeding colonies have access to nearby fields which provide foraging opportunities. Further study is needed to clarify specific habitat management that will enhance populations of flying insects preyed upon by swallows and other aerial insectivores.","PeriodicalId":49742,"journal":{"name":"Northeastern Naturalist","volume":"29 1","pages":"97 - 107"},"PeriodicalIF":0.4,"publicationDate":"2022-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44868619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kyle M. Knysh, Mark D. Saunders, Leah P. Macintyre, S. Courtenay, M. R. van den Heuvel
Abstract - Along the river–ocean transition, few freshwater species persist into polyhaline zones. Among those insect species capable of living in estuaries, it is unclear which Odonata, Trichoptera, and Coleoptera species can occur at intermittent or average salinities above 18 PSU. During surveys of fish and crustaceans in Prince Edward Island (PEI), we noted 3 unexpected insect species from within subtidal-channels. Multiple instars of Coenagrionidae n. det. and Enallagma civile (Familiar Bluet) were collected around marine macroalgae at 5 localities with 6-26 PSU salinities and observed emerging atop macroalgae. Also, collections of the larvae of the caddisfly Limnephilus externus (Limniphilidae), and adult Haliplus cribrarius (Haliplidae) beetles at sites with maxima of 23 and 20 PSU, respectively, suggest rare occurrences of these species within estuarine ecotones.
{"title":"Sometimes You Can Add a Bit of Salt: Additional Freshwater Insect Species in Canadian Estuaries","authors":"Kyle M. Knysh, Mark D. Saunders, Leah P. Macintyre, S. Courtenay, M. R. van den Heuvel","doi":"10.1656/045.029.0110","DOIUrl":"https://doi.org/10.1656/045.029.0110","url":null,"abstract":"Abstract - Along the river–ocean transition, few freshwater species persist into polyhaline zones. Among those insect species capable of living in estuaries, it is unclear which Odonata, Trichoptera, and Coleoptera species can occur at intermittent or average salinities above 18 PSU. During surveys of fish and crustaceans in Prince Edward Island (PEI), we noted 3 unexpected insect species from within subtidal-channels. Multiple instars of Coenagrionidae n. det. and Enallagma civile (Familiar Bluet) were collected around marine macroalgae at 5 localities with 6-26 PSU salinities and observed emerging atop macroalgae. Also, collections of the larvae of the caddisfly Limnephilus externus (Limniphilidae), and adult Haliplus cribrarius (Haliplidae) beetles at sites with maxima of 23 and 20 PSU, respectively, suggest rare occurrences of these species within estuarine ecotones.","PeriodicalId":49742,"journal":{"name":"Northeastern Naturalist","volume":"29 1","pages":"N9 - N17"},"PeriodicalIF":0.4,"publicationDate":"2022-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43023754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Restoration of degraded ecosystems requires assessing the status of the recovery and identifying key factors limiting the recovery. Nearly 4 decades of the reduction in smelter emissions, soil amelioration, and planting of ∼10 million trees and shrubs have led to extensive revegetation of emission-denuded landscapes in the Sudbury area, ON, Canada. To evaluate the state of recovery and identify factors affecting it, we surveyed woody plants and environmental correlates (soil pH, soil nutrient content, and soil metal content) along gradients of historical smelting impacts. Species richness declined from reference sites to high-impact sites, with impact sites having 23–33% fewer species compared to reference sites. Species composition varied along gradients of historical smelting impacts, with the difference attributable to low abundances or absences of one third of the 43 species found in the reference sites. Species richness and composition were associated with soil toxicity (as measured by metal content and pH) but not soil nutrients. However, the negative relationships between soil toxicity and plant community were attributable to the mediation effect of canopy cover, rather than the direct effect of soil toxicity. Sixty three percent of species that were uncommon or absent in impact sites (Abies balsamea [Balsam Fir], Acer pensylvanicum [Striped Maple], Acer spicatum [Mountain Maple], Betula alleghaniensis [Swamp Birch], Fraxinus nigra [Black Ash], Gaultheria procumbens [American Wintergreen], Linnaea borealis [Twinflower], Lonicera canadensis [Fly Honeysuckle], Lonicera hirsute [Hairy Honeysuckle], and Ostrya virginiana [American Hophornbeam]) were shade-tolerant and declined with declining canopy cover. These species were reported to be absent or uncommon in impact sites nearly 4 decades ago. Together, these results suggest that woody plant community has undergone limited recovery and that the recovery is hampered by poorly developed canopy cover rather than direct soil toxicity or nutrient deficiency. Accordingly, strategic interventions of canopy cover-mediated processes (e.g., shading and soil moisture) is needed to facilitate the recovery of the woody plant community in the smelter-denuded landscapes.
{"title":"Woody Plant Communities after 40 Years of Pollution Control and Restoration in Smelter-Denuded Landscapes","authors":"Kiyoshi Sasaki, Fumiko Shirakura, F. Mallory","doi":"10.1656/045.029.0108","DOIUrl":"https://doi.org/10.1656/045.029.0108","url":null,"abstract":"Abstract Restoration of degraded ecosystems requires assessing the status of the recovery and identifying key factors limiting the recovery. Nearly 4 decades of the reduction in smelter emissions, soil amelioration, and planting of ∼10 million trees and shrubs have led to extensive revegetation of emission-denuded landscapes in the Sudbury area, ON, Canada. To evaluate the state of recovery and identify factors affecting it, we surveyed woody plants and environmental correlates (soil pH, soil nutrient content, and soil metal content) along gradients of historical smelting impacts. Species richness declined from reference sites to high-impact sites, with impact sites having 23–33% fewer species compared to reference sites. Species composition varied along gradients of historical smelting impacts, with the difference attributable to low abundances or absences of one third of the 43 species found in the reference sites. Species richness and composition were associated with soil toxicity (as measured by metal content and pH) but not soil nutrients. However, the negative relationships between soil toxicity and plant community were attributable to the mediation effect of canopy cover, rather than the direct effect of soil toxicity. Sixty three percent of species that were uncommon or absent in impact sites (Abies balsamea [Balsam Fir], Acer pensylvanicum [Striped Maple], Acer spicatum [Mountain Maple], Betula alleghaniensis [Swamp Birch], Fraxinus nigra [Black Ash], Gaultheria procumbens [American Wintergreen], Linnaea borealis [Twinflower], Lonicera canadensis [Fly Honeysuckle], Lonicera hirsute [Hairy Honeysuckle], and Ostrya virginiana [American Hophornbeam]) were shade-tolerant and declined with declining canopy cover. These species were reported to be absent or uncommon in impact sites nearly 4 decades ago. Together, these results suggest that woody plant community has undergone limited recovery and that the recovery is hampered by poorly developed canopy cover rather than direct soil toxicity or nutrient deficiency. Accordingly, strategic interventions of canopy cover-mediated processes (e.g., shading and soil moisture) is needed to facilitate the recovery of the woody plant community in the smelter-denuded landscapes.","PeriodicalId":49742,"journal":{"name":"Northeastern Naturalist","volume":"29 1","pages":"82 - 96"},"PeriodicalIF":0.4,"publicationDate":"2022-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45357774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jason F. Cessna, R. L. Raesly, Jay V. Kilian, Staton M. Klein
Abstract - We examined aspects of the ecology of an isolated population of critically imperiled Enneacanthus chaetodon (Blackbanded Sunfish) in the only known extant locality in Maryland and made comparisons with an abundant and widespread sympatric congener, E. gloriosus (Bluespotted Sunfish). For Blackbanded Sunfish, we found population sizes were small, with abundance and age structure fluctuating throughout the course of the 9 years of observation, very low genetic diversity, and elevated levels of inbreeding. Habitat associations revealed a strong association of Blackbanded Sunfish with aquatic vegetation. We estimated a lifespan of 3–4 years for Blackbanded Sunfish, based on modal decomposition of length–frequency histograms. Bluespotted Sunfish exhibited much more stable population dynamics, larger population size, and a longer lifespan of 4–5 years. Our results indicate isolated Blackbanded Sunfish populations exhibit a clear susceptibility to environmental stochasticity and are unlikely to persist without intervention. More broadly, our results suggest that the long-term persistence of this species in much of its range is likely dependent on increasing connectivity between existing populations, (re)establishing populations in viable localities, maintaining suitable habitat, and reducing pressures from introduced centrarchids.
{"title":"Population Dynamics of an Isolated Population of Blackbanded Sunfish, Enneacanthus chaetodon, in Eastern Maryland","authors":"Jason F. Cessna, R. L. Raesly, Jay V. Kilian, Staton M. Klein","doi":"10.1656/045.029.0106","DOIUrl":"https://doi.org/10.1656/045.029.0106","url":null,"abstract":"Abstract - We examined aspects of the ecology of an isolated population of critically imperiled Enneacanthus chaetodon (Blackbanded Sunfish) in the only known extant locality in Maryland and made comparisons with an abundant and widespread sympatric congener, E. gloriosus (Bluespotted Sunfish). For Blackbanded Sunfish, we found population sizes were small, with abundance and age structure fluctuating throughout the course of the 9 years of observation, very low genetic diversity, and elevated levels of inbreeding. Habitat associations revealed a strong association of Blackbanded Sunfish with aquatic vegetation. We estimated a lifespan of 3–4 years for Blackbanded Sunfish, based on modal decomposition of length–frequency histograms. Bluespotted Sunfish exhibited much more stable population dynamics, larger population size, and a longer lifespan of 4–5 years. Our results indicate isolated Blackbanded Sunfish populations exhibit a clear susceptibility to environmental stochasticity and are unlikely to persist without intervention. More broadly, our results suggest that the long-term persistence of this species in much of its range is likely dependent on increasing connectivity between existing populations, (re)establishing populations in viable localities, maintaining suitable habitat, and reducing pressures from introduced centrarchids.","PeriodicalId":49742,"journal":{"name":"Northeastern Naturalist","volume":"29 1","pages":"73 - 81"},"PeriodicalIF":0.4,"publicationDate":"2022-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47941001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Lapin, N. Anich, Laura L. Jaskiewicz, A. J. DeValk, Michele P. Woodford
Abstract - We report the observation of a male Setophaga kirtlandii (Kirtland's Warbler) feeding nestlings in a Setophaga coronata (Yellow-rumped Warbler) nest in Vilas County, WI. To our knowledge, this is the first documented report of interspecific feeding in Kirtland's Warbler, adding to the list of species known to have exhibited this behavior.
{"title":"A Male Kirtland's Warbler Observed Feeding Yellow-Rumped Warbler Nestlings","authors":"C. Lapin, N. Anich, Laura L. Jaskiewicz, A. J. DeValk, Michele P. Woodford","doi":"10.1656/045.029.0107","DOIUrl":"https://doi.org/10.1656/045.029.0107","url":null,"abstract":"Abstract - We report the observation of a male Setophaga kirtlandii (Kirtland's Warbler) feeding nestlings in a Setophaga coronata (Yellow-rumped Warbler) nest in Vilas County, WI. To our knowledge, this is the first documented report of interspecific feeding in Kirtland's Warbler, adding to the list of species known to have exhibited this behavior.","PeriodicalId":49742,"journal":{"name":"Northeastern Naturalist","volume":"29 1","pages":"N6 - N8"},"PeriodicalIF":0.4,"publicationDate":"2022-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44759923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract - Bombus spp. (Bumble bees) face population declines, in part due to habitat loss. Roadside rights-of-way (ROWs) are potential habitats; however, they are highly disturbed due to roadside mowing and on-road traffic. We investigated whether these factors are associated with variation in abundance of bumble bees in highway roadside ROWs across New York State. We used sweep netting and photography along 30 highways with different mowing pattern (control, reduced) and traffic level (low, medium, high) treatments in 2019 and 2020. Very few bumble bees were observed (98% of n = 916 observations found 0). This result was potentially due to insufficient foraging plants or nesting areas. Further investigation is needed to understand how highway roadside ROWs can be high quality habitat for bumble bees.
{"title":"Bumble Bee (Bombus spp.) Abundance in New York Highway Roadsides across Levels of Roadside Mowing and Road Traffic","authors":"Alyssa Schoenfeldt, K. Whitney","doi":"10.1656/045.029.0105","DOIUrl":"https://doi.org/10.1656/045.029.0105","url":null,"abstract":"Abstract - Bombus spp. (Bumble bees) face population declines, in part due to habitat loss. Roadside rights-of-way (ROWs) are potential habitats; however, they are highly disturbed due to roadside mowing and on-road traffic. We investigated whether these factors are associated with variation in abundance of bumble bees in highway roadside ROWs across New York State. We used sweep netting and photography along 30 highways with different mowing pattern (control, reduced) and traffic level (low, medium, high) treatments in 2019 and 2020. Very few bumble bees were observed (98% of n = 916 observations found 0). This result was potentially due to insufficient foraging plants or nesting areas. Further investigation is needed to understand how highway roadside ROWs can be high quality habitat for bumble bees.","PeriodicalId":49742,"journal":{"name":"Northeastern Naturalist","volume":"29 1","pages":"55 - 72"},"PeriodicalIF":0.4,"publicationDate":"2022-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44416897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}