John David Lloyd
Research Subjects
Research Interests
John David Lloyd has a total of 725 co-authors. Here are the top co-authors by number of shared publications:
Gary L. Slater
J.D. Lloyd: Ecostudies Institute, P.O. Box 106, South Strafford, Vermont 05070
6 shared publications- Kent P. McFarland
Vermont Center for Ecostudies
4 shared publications - Thomas E. Martin
Montana Cooperative Wildlife Research Unit University of Montana Missoula Montana USA
4 shared publications Christopher C. Rimmer
Vermont Center for Ecostudies, Norwich, VT, United States of America
3 shared publications- Alecia Bellgrove
School of Life and Environmental Sciences, Deakin Marine Research and Innovation Centre, Deakin University Warrnambool Victoria Australia
2 shared publications - Alessandra Fidelis
Lab of Vegetation Ecology, Instituto de Biociências Universidade Estadual Paulista (UNESP) Rio Claro Brazil
2 shared publications
Latest Publications
- Top Cited PapersOpen Access
- 14 May 2025
- Published by Wiley in Global Ecology and Biogeography
- Vol. 34 (5)
BioTIME 2.0: Expanding and Improving a Database of Biodiversity Time Series
Motivation: Here, we make available a second version of the BioTIME database, which compiles records of abundance estimates for species in sample events of ecological assemblages through time. The updated version expands version 1.0 of the database by doubling the number of studies and includes substantial additional curation to the taxonomic accuracy of the records, as well as the metadata. Moreover, we now provide an R package (BioTIMEr) to facilitate use of the database.Main Types of Variables Included: The database is composed of one main data table containing the abundance records and 11 metadata tables. The data are organised in a hierarchy of scales where 11,989,233 records are nested in 1,603,067 sample events, from 553,253 sampling locations, which are nested in 708 studies. A study is defined as a sampling methodology applied to an assemblage for a minimum of 2 years.Spatial Location and Grain: Sampling locations in BioTIME are distributed across the planet, including marine, terrestrial and freshwater realms. Spatial grain size and extent vary across studies depending on sampling methodology. We recommend gridding of sampling locations into areas of consistent size.Time Period and Grain: The earliest time series in BioTIME start in 1874, and the most recent records are from 2023. Temporal grain and duration vary across studies. We recommend doing sample‐level rarefaction to ensure consistent sampling effort through time before calculating any diversity metric.Major Taxa and Level of Measurement: The database includes any eukaryotic taxa, with a combined total of 56,400 taxa.Software Format: csv and. SQL.
- 14 May 2025
- Published by Wiley in Global Ecology and Biogeography
- Vol. 34 (5)
Top Cited PapersOpen AccessBioTIME 2.0: Expanding and Improving a Database of Biodiversity Time Series
Motivation: Here, we make available a second version of the BioTIME database, which compiles records of abundance estimates for species in sample events of ecological assemblages through time. The updated version expands version 1.0 of the database by doubling the number of studies and includes substantial additional curation to the taxonomic accuracy of the records, as well as the metadata. Moreover, we now provide an R package (BioTIMEr) to facilitate use of the database.Main Types of Variables Included: The database is composed of one main data table containing the abundance records and 11 metadata tables. The data are organised in a hierarchy of scales where 11,989,233 records are nested in 1,603,067 sample events, from 553,253 sampling locations, which are nested in 708 studies. A study is defined as a sampling methodology applied to an assemblage for a minimum of 2 years.Spatial Location and Grain: Sampling locations in BioTIME are distributed across the planet, including marine, terrestrial and freshwater realms. Spatial grain size and extent vary across studies depending on sampling methodology. We recommend gridding of sampling locations into areas of consistent size.Time Period and Grain: The earliest time series in BioTIME start in 1874, and the most recent records are from 2023. Temporal grain and duration vary across studies. We recommend doing sample‐level rarefaction to ensure consistent sampling effort through time before calculating any diversity metric.Major Taxa and Level of Measurement: The database includes any eukaryotic taxa, with a combined total of 56,400 taxa.Software Format: csv and. SQL.
- Open Access
- 10 May 2023
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 18 (5) , e0284778
Seasonal patterns of bird and bat collision fatalities at wind turbines
Information on when birds and bats die from collisions with wind turbines can help refine efforts to minimize fatalities via curtailment of energy productions and can offer insight into the risk factors associated with collision fatalities. Using data pooled from 114 post-construction monitoring studies conducted at wind facilities across the United States, we described seasonal patterns of fatalities among birds and bats. Bat fatalities peaked in the fall. Silver-haired bat (Lasionycteris noctivagans), a long-distance migrant, and Mexican free-tailed bat (Tadarida brasiliensis) both showed maximum fatality counts later in the year–October and November, respectively–than any other bat species. The other common species in our sample–hoary bat (Aeorestes cinereus), Eastern red bat (Lasiurus borealis), and big brown bat (Eptesicus fuscus)–showed broadly overlapping peaks of fatality counts in August. Fatalities of silver-haired bat showed a smaller spring peak in some ecoregions; no other bat species exhibited this pattern. Seasonal patterns of bird fatalities varied among guilds. Woodland birds, many of which were long-distance migrants, showed two peaks in fatalities corresponding to spring and fall migration. Grassland birds and soaring birds, most of which were resident or short-distance migrants, did not exhibit strong seasonal peaks in fatalities. Species in these guilds tend to inhabit regions with extensive wind-energy development year-round, which may explain the more consistent numbers of fatalities that we observed. Our results highlight the value of pooling data to develop science-based solutions to reduce conflicts between wind-energy development and wildlife but also emphasize the need for more extensive data and standardization of post-construction monitoring to support more robust inferences regarding wind-wildlife interactions and collision risk.
- 10 May 2023
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 18 (5) , e0284778
Open AccessSeasonal patterns of bird and bat collision fatalities at wind turbines
Information on when birds and bats die from collisions with wind turbines can help refine efforts to minimize fatalities via curtailment of energy productions and can offer insight into the risk factors associated with collision fatalities. Using data pooled from 114 post-construction monitoring studies conducted at wind facilities across the United States, we described seasonal patterns of fatalities among birds and bats. Bat fatalities peaked in the fall. Silver-haired bat (Lasionycteris noctivagans), a long-distance migrant, and Mexican free-tailed bat (Tadarida brasiliensis) both showed maximum fatality counts later in the year–October and November, respectively–than any other bat species. The other common species in our sample–hoary bat (Aeorestes cinereus), Eastern red bat (Lasiurus borealis), and big brown bat (Eptesicus fuscus)–showed broadly overlapping peaks of fatality counts in August. Fatalities of silver-haired bat showed a smaller spring peak in some ecoregions; no other bat species exhibited this pattern. Seasonal patterns of bird fatalities varied among guilds. Woodland birds, many of which were long-distance migrants, showed two peaks in fatalities corresponding to spring and fall migration. Grassland birds and soaring birds, most of which were resident or short-distance migrants, did not exhibit strong seasonal peaks in fatalities. Species in these guilds tend to inhabit regions with extensive wind-energy development year-round, which may explain the more consistent numbers of fatalities that we observed. Our results highlight the value of pooling data to develop science-based solutions to reduce conflicts between wind-energy development and wildlife but also emphasize the need for more extensive data and standardization of post-construction monitoring to support more robust inferences regarding wind-wildlife interactions and collision risk.
- Open Access
- 17 June 2022
- Published by Wiley in Wildlife Society Bulletin
- Vol. 46 (3)
Prairie grouse and wind energy: The state of the science and implications for risk assessment
How to shape the anticipated build‐out of industrial‐scale renewable energy in a way that minimizes risk to wildlife remains contentious. The challenge of balancing wildlife conservation and decarbonization of the electricity sector is well illustrated in the grasslands and shrub‐steppe of North America. Here, several endemic species of grouse are the focus of intensive, long‐term conservation action by a host of governmental and nongovernmental entities, many of whom are now asking whether anticipated increases in the number of wind‐energy facilities will exacerbate declines or prevent recovery of these species. To address this question, we synthesized the potential consequences of wind‐energy development on prairie grouse. Published literature on behavior or demography of prairie grouse at wind‐energy facilities is sparse, with studies having been conducted at only 5 different facilities in the United States. Only 2 of these studies met the standard for robust impact analysis by collecting pre‐construction data and using control sites or gradient designs. Only one species, greater prairie chicken, had published results available for >1 facility. Most (10/12) studies also drew conclusions based on short (<4 years) periods of study, which is potentially problematic when studying highly philopatric species. Given these caveats, we found that, in the short‐term, adult survival and nest success appear largely unaffected in populations exposed to wind‐energy facilities. However, changes in habitat use by female greater sage‐grouse and female greater prairie‐chicken during some seasons and reduced lek persistence among male greater prairie‐chickens near wind turbines suggest behavioral responses that may have demographic consequences. Prairie grouse can coexist with wind‐energy facilities in some cases, at least in the short term, but important uncertainties remain, including the potential for long‐term, cumulative effects of the extensive development expected as states attempt to meet goals for generating electricity from renewable sources.
- 17 June 2022
- Published by Wiley in Wildlife Society Bulletin
- Vol. 46 (3)
Open AccessPrairie grouse and wind energy: The state of the science and implications for risk assessment
How to shape the anticipated build‐out of industrial‐scale renewable energy in a way that minimizes risk to wildlife remains contentious. The challenge of balancing wildlife conservation and decarbonization of the electricity sector is well illustrated in the grasslands and shrub‐steppe of North America. Here, several endemic species of grouse are the focus of intensive, long‐term conservation action by a host of governmental and nongovernmental entities, many of whom are now asking whether anticipated increases in the number of wind‐energy facilities will exacerbate declines or prevent recovery of these species. To address this question, we synthesized the potential consequences of wind‐energy development on prairie grouse. Published literature on behavior or demography of prairie grouse at wind‐energy facilities is sparse, with studies having been conducted at only 5 different facilities in the United States. Only 2 of these studies met the standard for robust impact analysis by collecting pre‐construction data and using control sites or gradient designs. Only one species, greater prairie chicken, had published results available for >1 facility. Most (10/12) studies also drew conclusions based on short (<4 years) periods of study, which is potentially problematic when studying highly philopatric species. Given these caveats, we found that, in the short‐term, adult survival and nest success appear largely unaffected in populations exposed to wind‐energy facilities. However, changes in habitat use by female greater sage‐grouse and female greater prairie‐chicken during some seasons and reduced lek persistence among male greater prairie‐chickens near wind turbines suggest behavioral responses that may have demographic consequences. Prairie grouse can coexist with wind‐energy facilities in some cases, at least in the short term, but important uncertainties remain, including the potential for long‐term, cumulative effects of the extensive development expected as states attempt to meet goals for generating electricity from renewable sources.
- 26 June 2019
- Published by Springer Nature in Ecotoxicology
- Vol. 28 (7) , 717-731
Bioaccumulation of methylmercury in wood frogs and spotted salamanders in Vermont vernal pools
Mercury (Hg) has accumulated in forested landscapes in the Northeastern U.S., and hotspots with enhanced deposition have been identified throughout the region. Due to a variety of favorable landscape characteristics, including relatively high dissolved organic carbon (DOC), fluctuating water levels, and low pH and dissolved oxygen, vernal pools provide ideal conditions for the conversion of Hg to its more toxic and bioavailable form, methylmercury (MeHg). Yet little is known about the concentrations, speciation, and bioavailability of Hg in vernal pools, or its bioaccumulation in vernal pool fauna and potential export into terrestrial systems. We investigated the role of forest cover type on the bioaccumulation of MeHg in wood frog (Lithobates sylvatica) and spotted salamander (Ambystoma maculatum) eggs, larvae, and adults, and investigated relationships among MeHg and water chemistry (pH, DOC). Water samples from pools located in coniferous stands had greater concentrations of THg and MeHg compared to deciduous pool water, and showed significant positive correlation to DOC (r = 0.683, P < 0.001) and correlated negatively with pH (r = −0.613, P < 0.001). Methylmercury levels in amphibian embryos were similar between the two species (L. sylvatica mean = 5.4 ng/g dw; A. maculatum mean = 3.5 ng/g dw). Concentrations of MeHg increased substantially in larvae, and were significantly greater in A. maculatum (mean = 237.6 ng/g ± 18.5 SE) than L. sylvatica larvae (62.5 ng/g ± 5.7 SE). Forest cover type did not explain variation in MeHg concentration among amphibian embryos or larvae. Methylmercury levels in adult tissue samples were significantly greater in A. maculatum (mean = 79.9 ng/g ± 8.9 SE) compared to L. sylvatica (mean = 47.7 ng/g ± 9.7 SE). This research demonstrates that vernal pools are important hotspots where amphibians bioaccumulate MeHg, which may then be transferred to terrestrial ecosystems. The abundance of amphibian larvae suggests they could be important bioindicators for monitoring MeHg loading and bioavailability.
- 26 June 2019
- Published by Springer Nature in Ecotoxicology
- Vol. 28 (7) , 717-731
Bioaccumulation of methylmercury in wood frogs and spotted salamanders in Vermont vernal pools
Mercury (Hg) has accumulated in forested landscapes in the Northeastern U.S., and hotspots with enhanced deposition have been identified throughout the region. Due to a variety of favorable landscape characteristics, including relatively high dissolved organic carbon (DOC), fluctuating water levels, and low pH and dissolved oxygen, vernal pools provide ideal conditions for the conversion of Hg to its more toxic and bioavailable form, methylmercury (MeHg). Yet little is known about the concentrations, speciation, and bioavailability of Hg in vernal pools, or its bioaccumulation in vernal pool fauna and potential export into terrestrial systems. We investigated the role of forest cover type on the bioaccumulation of MeHg in wood frog (Lithobates sylvatica) and spotted salamander (Ambystoma maculatum) eggs, larvae, and adults, and investigated relationships among MeHg and water chemistry (pH, DOC). Water samples from pools located in coniferous stands had greater concentrations of THg and MeHg compared to deciduous pool water, and showed significant positive correlation to DOC (r = 0.683, P < 0.001) and correlated negatively with pH (r = −0.613, P < 0.001). Methylmercury levels in amphibian embryos were similar between the two species (L. sylvatica mean = 5.4 ng/g dw; A. maculatum mean = 3.5 ng/g dw). Concentrations of MeHg increased substantially in larvae, and were significantly greater in A. maculatum (mean = 237.6 ng/g ± 18.5 SE) than L. sylvatica larvae (62.5 ng/g ± 5.7 SE). Forest cover type did not explain variation in MeHg concentration among amphibian embryos or larvae. Methylmercury levels in adult tissue samples were significantly greater in A. maculatum (mean = 79.9 ng/g ± 8.9 SE) compared to L. sylvatica (mean = 47.7 ng/g ± 9.7 SE). This research demonstrates that vernal pools are important hotspots where amphibians bioaccumulate MeHg, which may then be transferred to terrestrial ecosystems. The abundance of amphibian larvae suggests they could be important bioindicators for monitoring MeHg loading and bioavailability.
- Open Access
- 11 June 2019
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 14 (6) , e0214432
Short-term effects of hurricanes Maria and Irma on forest birds of Puerto Rico
We compared occupancy in local assemblages of birds in forested areas across Puerto Rico during a winter before (2015) and shortly after (2018) the passage of hurricanes Irma and Maria. Using dynamic community models analyzed within a Bayesian framework, we found significant changes in detectability, with some species becoming more readily detected after the storms and others becoming more difficult to detect during surveys. Changes in occupancy were equally mixed. Five species–mostly granivores and omnivores, but also Black-whiskered Vireo (Vireo altiloquus), a migratory insectivore–occupied more sites in 2018 than in 2015. Twelve species were less common after the hurricanes, including all of the obligate frugivores. Declines in site-occupancy rates were not only more common than increases, but tended to be of greater magnitude. Our results support the general conclusions that bird species respond largely independently to changes in forest structure caused by hurricanes, but that some dietary guilds, notably frugivores, are more sensitive and more likely to show changes in abundance or occupancy following strong storms.
- 11 June 2019
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 14 (6) , e0214432
Open AccessShort-term effects of hurricanes Maria and Irma on forest birds of Puerto Rico
We compared occupancy in local assemblages of birds in forested areas across Puerto Rico during a winter before (2015) and shortly after (2018) the passage of hurricanes Irma and Maria. Using dynamic community models analyzed within a Bayesian framework, we found significant changes in detectability, with some species becoming more readily detected after the storms and others becoming more difficult to detect during surveys. Changes in occupancy were equally mixed. Five species–mostly granivores and omnivores, but also Black-whiskered Vireo (Vireo altiloquus), a migratory insectivore–occupied more sites in 2018 than in 2015. Twelve species were less common after the hurricanes, including all of the obligate frugivores. Declines in site-occupancy rates were not only more common than increases, but tended to be of greater magnitude. Our results support the general conclusions that bird species respond largely independently to changes in forest structure caused by hurricanes, but that some dietary guilds, notably frugivores, are more sensitive and more likely to show changes in abundance or occupancy following strong storms.
- Open Access
Short-term effects of hurricanes Maria and Irma on forest birds of Puerto Rico
We compared occupancy in local assemblages of birds in forested areas across Puerto Rico during a winter before (2015) and shortly after (2018) the passage of hurricanes Irma and Maria. Using dynamic community models analyzed within a Bayesian framework, we found significant changes in detectability, with some species becoming more readily detected after the storms and others becoming more difficult to detect during surveys. Changes in occupancy were equally mixed. Five species – mostly granivores and omnivores, but also Black-whiskered Vireo ( Vireo altiloquus ), a migratory insectivore – occupied more sites in 2018 than in 2015. Thirteen species were less common after the hurricanes, including all of the obligate frugivores. Declines in site-occupancy rates were not only more common than increases, but tended to be of greater magnitude. Our results support the general conclusions that bird species respond largely independently to changes in forest structure caused by hurricanes, but that some dietary guilds, notably frugivores, are more sensitive and more likely to show changes in abundance or occupancy following strong storms.
Open AccessShort-term effects of hurricanes Maria and Irma on forest birds of Puerto Rico
We compared occupancy in local assemblages of birds in forested areas across Puerto Rico during a winter before (2015) and shortly after (2018) the passage of hurricanes Irma and Maria. Using dynamic community models analyzed within a Bayesian framework, we found significant changes in detectability, with some species becoming more readily detected after the storms and others becoming more difficult to detect during surveys. Changes in occupancy were equally mixed. Five species – mostly granivores and omnivores, but also Black-whiskered Vireo ( Vireo altiloquus ), a migratory insectivore – occupied more sites in 2018 than in 2015. Thirteen species were less common after the hurricanes, including all of the obligate frugivores. Declines in site-occupancy rates were not only more common than increases, but tended to be of greater magnitude. Our results support the general conclusions that bird species respond largely independently to changes in forest structure caused by hurricanes, but that some dietary guilds, notably frugivores, are more sensitive and more likely to show changes in abundance or occupancy following strong storms.
- Open Access
- 22 February 2019
- Published by Cold Spring Harbor Laboratory in bioRxiv
- p. 558346
Forest change within and outside protected areas in the Dominican Republic, 2000-2016
We used Landsat-based estimates of tree cover change to document the loss and gain of forest in the Dominican Republic between 2000 and 2016. Overall, 2,795 km2 of forest were lost, with forest gain occurring on only 393 km2, yielding a net loss of 2,402 km2 of forest, a decline of 11.1% or 0.7% per year. Deforestation occurred in all of the major forest types in the country, and ranged from a 13% decline in the area of semi-moist broadleaf forest to a 5.9% loss of cloud forest, mostly attributed to agriculture. Fire was a significant driver of forest loss only in Hispaniolan pine (Pinus occidentalis) forests and, to a lesser extent, in adjacent cloud forest. Deforestation rates were lower within protected areas, especially in dry and semi-moist broadleaf forests at lower elevations. Protected areas had a smaller, and generally negligible, effect on rates of forest loss in pine forest and cloud forest, largely due to the effects of several large wildfires. Overall, rates of deforestation in the Dominican Republic were higher than regional averages from across the Neotropics and appeared to have accelerated during the later years of our study period. Stemming deforestation will likely require enforcement of prohibitions on large-scale agricultural production within protected areas and development of alternatives to short-cycle, shifting agriculture.
- 22 February 2019
- Published by Cold Spring Harbor Laboratory in bioRxiv
- p. 558346
Open AccessForest change within and outside protected areas in the Dominican Republic, 2000-2016
We used Landsat-based estimates of tree cover change to document the loss and gain of forest in the Dominican Republic between 2000 and 2016. Overall, 2,795 km2 of forest were lost, with forest gain occurring on only 393 km2, yielding a net loss of 2,402 km2 of forest, a decline of 11.1% or 0.7% per year. Deforestation occurred in all of the major forest types in the country, and ranged from a 13% decline in the area of semi-moist broadleaf forest to a 5.9% loss of cloud forest, mostly attributed to agriculture. Fire was a significant driver of forest loss only in Hispaniolan pine (Pinus occidentalis) forests and, to a lesser extent, in adjacent cloud forest. Deforestation rates were lower within protected areas, especially in dry and semi-moist broadleaf forests at lower elevations. Protected areas had a smaller, and generally negligible, effect on rates of forest loss in pine forest and cloud forest, largely due to the effects of several large wildfires. Overall, rates of deforestation in the Dominican Republic were higher than regional averages from across the Neotropics and appeared to have accelerated during the later years of our study period. Stemming deforestation will likely require enforcement of prohibitions on large-scale agricultural production within protected areas and development of alternatives to short-cycle, shifting agriculture.
- Open Access
- 1 January 2019
- Published by Resilience Alliance, Inc. in Avian Conservation and Ecology
- Vol. 14 (2)
Apparent survival of a range-restricted montane forest bird species is influenced by weather throughout the annual cycle
Hill, J. M., J. D. Lloyd, K. P. McFarland, and C. C. Rimmer. 2019. Apparent survival of a range-restricted montane forest bird species is influenced by weather throughout the annual cycle. Avian Conservation and Ecology 14(2):16. https://doi.org/10.5751/ACE-01462-140216
- 1 January 2019
- Published by Resilience Alliance, Inc. in Avian Conservation and Ecology
- Vol. 14 (2)
Open AccessApparent survival of a range-restricted montane forest bird species is influenced by weather throughout the annual cycle
Hill, J. M., J. D. Lloyd, K. P. McFarland, and C. C. Rimmer. 2019. Apparent survival of a range-restricted montane forest bird species is influenced by weather throughout the annual cycle. Avian Conservation and Ecology 14(2):16. https://doi.org/10.5751/ACE-01462-140216
- Open Access
The recent expansion of Fox Sparrow (Passerella iliaca iliaca) breeding range into the northeastern United States
The breeding range of the Eastern Fox Sparrow (Passerella iliaca iliaca) is generally recognized as comprising the boreal forest of Canada. However, recent observations suggest that the species is present during the summer months throughout much of the northeastern US, unexpected for a species characterized as a passage migrant in the region. To clarify, I conducted a literature review to document the historical status of the species in the northeastern US and then analyzed observations submitted to eBird to describe its recent and current status in the region. Historical accounts consistently identify Fox Sparrow as a passage migrant through the region during early spring and late fall. Beginning in the early 1980s, observers began noting regular extralimital records of Fox Sparrow in northern Maine. A single nest was discovered in the state in 1983, and another in northern New Hampshire in 1997. Despite the paucity of breeding records, observations submitted to eBird suggest that the southern limit of the breeding range of Fox Sparrow has expanded rapidly to the south and west in recent years. The proportion of complete checklists submitted to eBird that contained at least one observation of Fox Sparrow grew at an annual rate of 18% from 2003–2016 and was independent of observer effort. Fox Sparrow now occurs regularly on mountaintops and in young stands of spruce (Piceaspp.) and balsam fir (Abies balsamea) during the breeding season throughout northern and western Maine and northern New Hampshire, with occasional records from the Green Mountains of Vermont and the Adirondack Mountains of New York. The cause of this rapid expansion of its breeding range is unknown, but may be related to an increase in the amount of young conifer forest in the northeastern US created by commercial timber harvest.
Open AccessThe recent expansion of Fox Sparrow (Passerella iliaca iliaca) breeding range into the northeastern United States
The breeding range of the Eastern Fox Sparrow (Passerella iliaca iliaca) is generally recognized as comprising the boreal forest of Canada. However, recent observations suggest that the species is present during the summer months throughout much of the northeastern US, unexpected for a species characterized as a passage migrant in the region. To clarify, I conducted a literature review to document the historical status of the species in the northeastern US and then analyzed observations submitted to eBird to describe its recent and current status in the region. Historical accounts consistently identify Fox Sparrow as a passage migrant through the region during early spring and late fall. Beginning in the early 1980s, observers began noting regular extralimital records of Fox Sparrow in northern Maine. A single nest was discovered in the state in 1983, and another in northern New Hampshire in 1997. Despite the paucity of breeding records, observations submitted to eBird suggest that the southern limit of the breeding range of Fox Sparrow has expanded rapidly to the south and west in recent years. The proportion of complete checklists submitted to eBird that contained at least one observation of Fox Sparrow grew at an annual rate of 18% from 2003–2016 and was independent of observer effort. Fox Sparrow now occurs regularly on mountaintops and in young stands of spruce (Piceaspp.) and balsam fir (Abies balsamea) during the breeding season throughout northern and western Maine and northern New Hampshire, with occasional records from the Green Mountains of Vermont and the Adirondack Mountains of New York. The cause of this rapid expansion of its breeding range is unknown, but may be related to an increase in the amount of young conifer forest in the northeastern US created by commercial timber harvest.
- Open Access
- 12 September 2018
- Published by PeerJ in PeerJ Preprints
The recent expansion of Fox Sparrow (Passerella iliaca iliaca) breeding range into the northeastern United States
The breeding range of the Red Fox Sparrow (Passerella iliaca iliaca) is generally recognized as comprising the boreal forest of Canada. However, recent observations suggest that the species is present during the summer months throughout much of the northeastern U.S., unexpected for a species characterized as a passage migrant in the region. To clarify, I conducted a literature review to document the historical status of the species in the northeastern U.S. and then analyzed observations submitted to eBird to describe its recent and current status in the region. Historical accounts consistently identify Fox Sparrow as a passage migrant through the region during early spring and late fall. Beginning in the early 1980s, observers began noting regular extralimital records of Fox Sparrow in northern Maine. A single nest was discovered in the state in 1983, and another in northern New Hampshire in 1997. Despite the paucity of breeding records, observations submitted to eBird suggest that the southern limit of the breeding range of Fox Sparrow has expanded rapidly to the south and west in recent years. The proportion of complete checklists submitted to eBird that contained at least one observation of Fox Sparrow grew at an annual rate of 18% from 2003-2016 and was independent of observer effort. Fox Sparrow now occurs regularly on mountaintops and in young stands of spruce (Picea spp.) and balsam fir (Abies balsamea) during the breeding season throughout northern and western Maine and northern New Hampshire, with occasional records from the Green Mountains of Vermont and the Adirondack Mountains of New York. The cause of this rapid expansion of its breeding range is unknown, but may be related to an increase in the amount of young conifer forest in the northeastern U.S. created by commercial timber harvest.
- 12 September 2018
- Published by PeerJ in PeerJ Preprints
Open AccessThe recent expansion of Fox Sparrow (Passerella iliaca iliaca) breeding range into the northeastern United States
The breeding range of the Red Fox Sparrow (Passerella iliaca iliaca) is generally recognized as comprising the boreal forest of Canada. However, recent observations suggest that the species is present during the summer months throughout much of the northeastern U.S., unexpected for a species characterized as a passage migrant in the region. To clarify, I conducted a literature review to document the historical status of the species in the northeastern U.S. and then analyzed observations submitted to eBird to describe its recent and current status in the region. Historical accounts consistently identify Fox Sparrow as a passage migrant through the region during early spring and late fall. Beginning in the early 1980s, observers began noting regular extralimital records of Fox Sparrow in northern Maine. A single nest was discovered in the state in 1983, and another in northern New Hampshire in 1997. Despite the paucity of breeding records, observations submitted to eBird suggest that the southern limit of the breeding range of Fox Sparrow has expanded rapidly to the south and west in recent years. The proportion of complete checklists submitted to eBird that contained at least one observation of Fox Sparrow grew at an annual rate of 18% from 2003-2016 and was independent of observer effort. Fox Sparrow now occurs regularly on mountaintops and in young stands of spruce (Picea spp.) and balsam fir (Abies balsamea) during the breeding season throughout northern and western Maine and northern New Hampshire, with occasional records from the Green Mountains of Vermont and the Adirondack Mountains of New York. The cause of this rapid expansion of its breeding range is unknown, but may be related to an increase in the amount of young conifer forest in the northeastern U.S. created by commercial timber harvest.