Pub Date : 2021-10-18DOI: 10.1674/0003-0031-186.2.291
T. Menzel, William Beghun, J. Farmer, J. T. Looney, Jacson Lee Moody, Christopher White
Abstract. The purpose of this project was to isolate and describe the behaviors of individuals of two ant species, Aphaenogaster carolinensis Wheeler and Nylanderia faisonensis Forel, during their interference interactions, and to relate those to effects on colonies and their access to resources. Videos were taken of baited index cards from within the shared habitat of the ant species in northeast Georgia forests. Two measures of individual behavior, change in speed and deflection, and three measures of colony behavior, time to first ant, recruitment time and maximum number of individuals, were collected from video. Nest occurrence for each species within a specified distance of baits was determined for both species as well. Nylanderia faisonensis saw greater change in speed and deflection angle in response to species interactions than A. carolinensis. Locations with N. faisonensis nests had a higher maximum number of individuals of both species. Nylanderia faisonensis had longer recruitment times at locations with A. carolinensis nests. Although N. faisonensis was always the aggressor, they experienced clear negative consequences of their interactions.
{"title":"Individual and Colony Level Effects of Interactions between Two Common Forest Ant Species, Aphaenogaster carolinensis (Wheeler) and Nylanderia faisonensis (Forel)","authors":"T. Menzel, William Beghun, J. Farmer, J. T. Looney, Jacson Lee Moody, Christopher White","doi":"10.1674/0003-0031-186.2.291","DOIUrl":"https://doi.org/10.1674/0003-0031-186.2.291","url":null,"abstract":"Abstract. The purpose of this project was to isolate and describe the behaviors of individuals of two ant species, Aphaenogaster carolinensis Wheeler and Nylanderia faisonensis Forel, during their interference interactions, and to relate those to effects on colonies and their access to resources. Videos were taken of baited index cards from within the shared habitat of the ant species in northeast Georgia forests. Two measures of individual behavior, change in speed and deflection, and three measures of colony behavior, time to first ant, recruitment time and maximum number of individuals, were collected from video. Nest occurrence for each species within a specified distance of baits was determined for both species as well. Nylanderia faisonensis saw greater change in speed and deflection angle in response to species interactions than A. carolinensis. Locations with N. faisonensis nests had a higher maximum number of individuals of both species. Nylanderia faisonensis had longer recruitment times at locations with A. carolinensis nests. Although N. faisonensis was always the aggressor, they experienced clear negative consequences of their interactions.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45960938","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}
Pub Date : 2021-10-18DOI: 10.1674/0003-0031-186.2.157
S.S. Keretz, D. Woolnough, T. Morris, E. Roseman, A. Elgin, D. Zanatta
Abstract. There are serious concerns for native freshwater mussel survival (Bivalvia: Unionidae) in the Laurentian Great Lakes region after populations were seemingly pushed to the brink of extirpation following the introduction of dreissenid mussels (Dreissena polymorpha and D. rostriformis bugensis) in the mid-1980s. The Detroit River was the first major river system in North America to be invaded by dreissenids, and unionids were considered extirpated from the river by 1998. Since then several unionid refuges (areas with relatively low dreissenid impact and surviving unionids) have been found in coastal areas of lakes St. Clair and Erie, but no documentation exists in the Detroit River. To assess dreissenid presence and potential unionid persistence, a mixture of stratified random, historical, and potential refuge sites were surveyed during summer 2019 in the Detroit River. Unionid and dreissenid habitat use was further investigated with analysis of variance and classification tree analyses. Of the 56 sites surveyed, only five sites had live unionids totaling 220 animals of 11 species. More than 2000 unionid shells of 31 species were collected from 39 sites, confirming the large and diverse unionid populations that existed prior to the dreissenid invasion. Ninety-eight percent of live unionids found showed evidence of past or present dreissenid attachment. Estimated dreissenid densities were highly variable with river location and ranged from 0 to 5673 live individuals per m2, with the largest densities concentrated in the upstream half of the Detroit River. Despite their previously assumed extirpation from the Detroit River, live unionids were found during this comprehensive survey. Although only 40% of the historical species within the unionid assemblage remains, our results suggest, in the right conditions, some coexistence is possible among some species of unionids and dreissenids in this large river system.
{"title":"Limited Co- existence of Native Unionids and Invasive Dreissenid Mussels more than 30 Y Post Dreissenid Invasion in a Large River System","authors":"S.S. Keretz, D. Woolnough, T. Morris, E. Roseman, A. Elgin, D. Zanatta","doi":"10.1674/0003-0031-186.2.157","DOIUrl":"https://doi.org/10.1674/0003-0031-186.2.157","url":null,"abstract":"Abstract. There are serious concerns for native freshwater mussel survival (Bivalvia: Unionidae) in the Laurentian Great Lakes region after populations were seemingly pushed to the brink of extirpation following the introduction of dreissenid mussels (Dreissena polymorpha and D. rostriformis bugensis) in the mid-1980s. The Detroit River was the first major river system in North America to be invaded by dreissenids, and unionids were considered extirpated from the river by 1998. Since then several unionid refuges (areas with relatively low dreissenid impact and surviving unionids) have been found in coastal areas of lakes St. Clair and Erie, but no documentation exists in the Detroit River. To assess dreissenid presence and potential unionid persistence, a mixture of stratified random, historical, and potential refuge sites were surveyed during summer 2019 in the Detroit River. Unionid and dreissenid habitat use was further investigated with analysis of variance and classification tree analyses. Of the 56 sites surveyed, only five sites had live unionids totaling 220 animals of 11 species. More than 2000 unionid shells of 31 species were collected from 39 sites, confirming the large and diverse unionid populations that existed prior to the dreissenid invasion. Ninety-eight percent of live unionids found showed evidence of past or present dreissenid attachment. Estimated dreissenid densities were highly variable with river location and ranged from 0 to 5673 live individuals per m2, with the largest densities concentrated in the upstream half of the Detroit River. Despite their previously assumed extirpation from the Detroit River, live unionids were found during this comprehensive survey. Although only 40% of the historical species within the unionid assemblage remains, our results suggest, in the right conditions, some coexistence is possible among some species of unionids and dreissenids in this large river system.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44848059","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}
Pub Date : 2021-10-18DOI: 10.1674/0003-0031-186.2.215
Thanchira Suriyamongkol, Laramie B. Mahan, Alissa A. Kreikemeier, Vinicius Ortega-Berno, Ivana Mali
Abstract. The ornate box turtle (Terrapene ornata) is a terrestrial Emydid, listed as near threatened by the International Union for Conservation of Nature Redlist due to habitat destruction, degradation, habitat fragmentation, commercial harvest, and road mortality. Terrapene ornata is secretive, which can pose a challenge to conducting systematic surveys and assessing species status. Studies on the species' biology have relied on opportunistic encounters on the road and the use of radiotelemetry. The objective of this study was to assess the feasibility of using transect line surveys in single season occupancy surveys for T. ornata in Roosevelt County, New Mexico. We further used radiotelemetry to link turtle activity patterns with environmental conditions to aid in understanding detectability of the species. Our occupancy model showed the detection probability to be influenced by individual observers and the time of day. We found T. ornata to most likely occupy habitats with less dense ground cover and avoid highly altered habitats (i.e., cultivated fields). Radiotelemetry further revealed the effect humidity, time of day, and temperature on turtle activity patterns. The lowest activity occurred between 1200–1700 h, whereas peak activity occurred in early morning hours (0600–0900 h). The peak activity occurred between ∼10–25 C and was promoted by higher humidity. Our study represents the first attempt at using transect line surveys for occupancy modeling framework for the ornate box turtles. We suggest that future studies on box turtle occupancy focus on finer scale habitat assessment that would also include vegetation, invertebrate, and small mammal surveys.
{"title":"Understanding Habitat Use and Activity Patterns of Ornate Box Turtle (Terrapene ornata) in Eastern New Mexico","authors":"Thanchira Suriyamongkol, Laramie B. Mahan, Alissa A. Kreikemeier, Vinicius Ortega-Berno, Ivana Mali","doi":"10.1674/0003-0031-186.2.215","DOIUrl":"https://doi.org/10.1674/0003-0031-186.2.215","url":null,"abstract":"Abstract. The ornate box turtle (Terrapene ornata) is a terrestrial Emydid, listed as near threatened by the International Union for Conservation of Nature Redlist due to habitat destruction, degradation, habitat fragmentation, commercial harvest, and road mortality. Terrapene ornata is secretive, which can pose a challenge to conducting systematic surveys and assessing species status. Studies on the species' biology have relied on opportunistic encounters on the road and the use of radiotelemetry. The objective of this study was to assess the feasibility of using transect line surveys in single season occupancy surveys for T. ornata in Roosevelt County, New Mexico. We further used radiotelemetry to link turtle activity patterns with environmental conditions to aid in understanding detectability of the species. Our occupancy model showed the detection probability to be influenced by individual observers and the time of day. We found T. ornata to most likely occupy habitats with less dense ground cover and avoid highly altered habitats (i.e., cultivated fields). Radiotelemetry further revealed the effect humidity, time of day, and temperature on turtle activity patterns. The lowest activity occurred between 1200–1700 h, whereas peak activity occurred in early morning hours (0600–0900 h). The peak activity occurred between ∼10–25 C and was promoted by higher humidity. Our study represents the first attempt at using transect line surveys for occupancy modeling framework for the ornate box turtles. We suggest that future studies on box turtle occupancy focus on finer scale habitat assessment that would also include vegetation, invertebrate, and small mammal surveys.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42895107","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}
Pub Date : 2021-10-18DOI: 10.1674/0003-0031-186.2.176
K. A. Haberyan
Abstract. Mozingo Lake, a reservoir in the mid-continental United States, was sampled 63 times between January 1999 and October 2015. Prior to 2005, phytoplankton biovolume was largely composed of Cryptomonas and cyanobacteria (mostly Aphanizomenon); these taxa correlated with the abundance of Daphnia and juvenile copepods, and were also influenced by competition between cyanobacteria and bacillariophytes. These relationships suggest the zooplankton community was primarily controlled by bottom-up processes during this time. In 2005, gizzard shad (Dorosoma cepedianum) first appeared in the lake, coinciding with the first spined and helmeted forms of Daphnia as well as their decline from 39% to 3% of zooplankton; the relative abundance of juvenile copepods increased concurrently. By 2007 phytoplankton biovolume had decreased by 88%. Although all phytoplankton phyla declined in absolute abundance, some were more heavily impacted. The relative abundance of Aphanizomenon declined from 50% to 6% of the phytoplankton biovolume; Cryptomonas remained common, but bacillariophytes became codominant. Despite the steep decline in phytoplankton biovolume, several important trophic interactions did not change: phytoplankton biovolume continued to control juvenile copepods, and competition continued between cyanobacteria and bacillariophytes. Although juvenile copepods continued to compete with Daphnia, the scarcity of the latter allowed a relative expansion of juvenile copepods and bacillariophytes. Because very few of the standard parameters correlated with phytoplankton, it seems likely that most of the changes were caused by the introduction of gizzard shad, which is an intense consumer of cyanobacteria and Daphnia. Gizzard shad likely initiated a trophic cascade both directly (through consumption) and indirectly (by shifting competition). Although other factors may have played a role, it seems clear that the introduction of gizzard shad can cause dramatic changes in both the zooplankton and phytoplankton communities by altering species relationships in top-down, bottom-up, as well as lateral control processes.
{"title":"A Trophic Cascade Following the Introduction of an Omnivorous Fish, Dorosoma cepedianum, in a Mid-continental Reservoir (Mozingo Studies IV)","authors":"K. A. Haberyan","doi":"10.1674/0003-0031-186.2.176","DOIUrl":"https://doi.org/10.1674/0003-0031-186.2.176","url":null,"abstract":"Abstract. Mozingo Lake, a reservoir in the mid-continental United States, was sampled 63 times between January 1999 and October 2015. Prior to 2005, phytoplankton biovolume was largely composed of Cryptomonas and cyanobacteria (mostly Aphanizomenon); these taxa correlated with the abundance of Daphnia and juvenile copepods, and were also influenced by competition between cyanobacteria and bacillariophytes. These relationships suggest the zooplankton community was primarily controlled by bottom-up processes during this time. In 2005, gizzard shad (Dorosoma cepedianum) first appeared in the lake, coinciding with the first spined and helmeted forms of Daphnia as well as their decline from 39% to 3% of zooplankton; the relative abundance of juvenile copepods increased concurrently. By 2007 phytoplankton biovolume had decreased by 88%. Although all phytoplankton phyla declined in absolute abundance, some were more heavily impacted. The relative abundance of Aphanizomenon declined from 50% to 6% of the phytoplankton biovolume; Cryptomonas remained common, but bacillariophytes became codominant. Despite the steep decline in phytoplankton biovolume, several important trophic interactions did not change: phytoplankton biovolume continued to control juvenile copepods, and competition continued between cyanobacteria and bacillariophytes. Although juvenile copepods continued to compete with Daphnia, the scarcity of the latter allowed a relative expansion of juvenile copepods and bacillariophytes. Because very few of the standard parameters correlated with phytoplankton, it seems likely that most of the changes were caused by the introduction of gizzard shad, which is an intense consumer of cyanobacteria and Daphnia. Gizzard shad likely initiated a trophic cascade both directly (through consumption) and indirectly (by shifting competition). Although other factors may have played a role, it seems clear that the introduction of gizzard shad can cause dramatic changes in both the zooplankton and phytoplankton communities by altering species relationships in top-down, bottom-up, as well as lateral control processes.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43294872","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}
Pub Date : 2021-10-18DOI: 10.1674/0003-0031-186.2.245
Heather Herakovich, N. Barber, H. Jones
Abstract. Grassland bird responses to grazing and prescribed fire are species-specific and are primarily known from systems with cattle as the predominant grazer. There is less knowledge of how grazing by bison impacts grassland birds, especially in sites restored and reconstructed from row-crop agriculture. Working at a tallgrass prairie site consisting of restored and remnant prairie in the years following bison reintroduction and ongoing prescribed burning, we assessed overall species richness and the relative detection frequency of five focal species (Grasshopper Sparrow, Henslow's Sparrow, Dickcissel, Eastern Meadowlark, and Brown-headed Cowbird). We used stationary bioacoustics recorders to record the soundscape during the summer breeding season in areas with and without bison from 2016 to 2018. Species richness and the detection frequencies of our focal species were not influenced by bison disturbance. Grasshopper Sparrow and Dickcissel detection frequency increased slightly in response to prescribed fire, whereas Henslow's Sparrow detection frequency decreased. Time since sites were restored was a predominant factor that influenced the variation in detection frequency of Henslow's Sparrows and Eastern Meadowlarks, likely due to vegetation differences in restored versus remnant sites and each species' vegetation structure preferences. Brown-headed Cowbird detection frequency was unaffected by bison presence, prescribed fire, or time since restoration, but varied among sampling years. Our focal species showed no response to bison disturbance 4 y after the bison reintroduction. This suggests there could be a time-lag for a response or that these species will not respond to the bison reintroduction at this study site.
{"title":"Assessing the Impacts of Prescribed Fire and Bison Disturbance on Birds Using Bioacoustic Recorders","authors":"Heather Herakovich, N. Barber, H. Jones","doi":"10.1674/0003-0031-186.2.245","DOIUrl":"https://doi.org/10.1674/0003-0031-186.2.245","url":null,"abstract":"Abstract. Grassland bird responses to grazing and prescribed fire are species-specific and are primarily known from systems with cattle as the predominant grazer. There is less knowledge of how grazing by bison impacts grassland birds, especially in sites restored and reconstructed from row-crop agriculture. Working at a tallgrass prairie site consisting of restored and remnant prairie in the years following bison reintroduction and ongoing prescribed burning, we assessed overall species richness and the relative detection frequency of five focal species (Grasshopper Sparrow, Henslow's Sparrow, Dickcissel, Eastern Meadowlark, and Brown-headed Cowbird). We used stationary bioacoustics recorders to record the soundscape during the summer breeding season in areas with and without bison from 2016 to 2018. Species richness and the detection frequencies of our focal species were not influenced by bison disturbance. Grasshopper Sparrow and Dickcissel detection frequency increased slightly in response to prescribed fire, whereas Henslow's Sparrow detection frequency decreased. Time since sites were restored was a predominant factor that influenced the variation in detection frequency of Henslow's Sparrows and Eastern Meadowlarks, likely due to vegetation differences in restored versus remnant sites and each species' vegetation structure preferences. Brown-headed Cowbird detection frequency was unaffected by bison presence, prescribed fire, or time since restoration, but varied among sampling years. Our focal species showed no response to bison disturbance 4 y after the bison reintroduction. This suggests there could be a time-lag for a response or that these species will not respond to the bison reintroduction at this study site.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47895645","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}
Pub Date : 2021-10-18DOI: 10.1674/0003-0031-186.2.199
C. Mettler, Miguel Aguirre-Morales, Justin Harmeson, W. Robinson, B. E. Carlson
Abstract. The effects of many pesticides on aquatic ecosystems remain poorly understood, especially in naturalistic communities in which organisms are connected by a complex array of direct and indirect interactions. Moreover, multiple stressors can interact, and the addition of apex predators, such as fish, may introduce additional ecosystem changes that exacerbate or mitigate pesticide effects. Despite being both common and environmentally persistent, the effects of the herbicide metolachlor on realistic aquatic communities have received insufficient research attention. We tested the effects of metolachlor on pond mesocosms at three concentrations (0, 20, and 80 ppb), along with the presence vs. absence of fish (black crappie, Pomoxis nigromaculatus) to determine the independent and combined effects of these two environmental changes. We found both metolachlor and fish altered the pond mesocosms, but their effects did not interact. Metolachlor reduced phytoplankton as expected, but had nonlinear effects on dissolved oxygen. Metolachlor also altered tadpole behavior, making them less prone to hiding. Fish presence increased periphyton and decreased snail counts, as well as changing the behavior of tadpoles, reducing their hiding behavior. This work demonstrates previously undocumented effects of metolachlor in the presence and absence of fish and suggests future avenues of investigation.
{"title":"Effects of the Herbicide Metolachlor and Fish Presence on Pond Mesocosm Communities","authors":"C. Mettler, Miguel Aguirre-Morales, Justin Harmeson, W. Robinson, B. E. Carlson","doi":"10.1674/0003-0031-186.2.199","DOIUrl":"https://doi.org/10.1674/0003-0031-186.2.199","url":null,"abstract":"Abstract. The effects of many pesticides on aquatic ecosystems remain poorly understood, especially in naturalistic communities in which organisms are connected by a complex array of direct and indirect interactions. Moreover, multiple stressors can interact, and the addition of apex predators, such as fish, may introduce additional ecosystem changes that exacerbate or mitigate pesticide effects. Despite being both common and environmentally persistent, the effects of the herbicide metolachlor on realistic aquatic communities have received insufficient research attention. We tested the effects of metolachlor on pond mesocosms at three concentrations (0, 20, and 80 ppb), along with the presence vs. absence of fish (black crappie, Pomoxis nigromaculatus) to determine the independent and combined effects of these two environmental changes. We found both metolachlor and fish altered the pond mesocosms, but their effects did not interact. Metolachlor reduced phytoplankton as expected, but had nonlinear effects on dissolved oxygen. Metolachlor also altered tadpole behavior, making them less prone to hiding. Fish presence increased periphyton and decreased snail counts, as well as changing the behavior of tadpoles, reducing their hiding behavior. This work demonstrates previously undocumented effects of metolachlor in the presence and absence of fish and suggests future avenues of investigation.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48753159","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}
Pub Date : 2021-09-11DOI: 10.1674/0003-0031-188.2.137
Robert G. Laport, Zoe S. Brookover, Brian D. Christman, Nguefack Julienne, Kevin D. Philley, J. H. Craddock
Abstract. The unintentional introduction and rapid spread of chestnut blight (caused by Cryphonectria parasitica (Murr.) Barr) in the early 20th century resulted in the demise of American chestnut (Castanea dentata (Marsh.) Borkh.; Fagaceae) as a major component of forest canopies resulting in negative impacts on eastern forest communities. Research efforts over the last century have documented the persistence of occasional trees and root crown/ stump sprouts throughout much of the species' historic range, providing the basis for ongoing breeding of blight-resistant trees and restoration efforts. Here we use environmental niche modeling to investigate whether environmentally suitable habitat remains for remnant trees throughout the southwestern historical range, and to evaluate the reintroduction potential of this relatively understudied part of the historical distribution. We also use stage-structured matrix projection models to investigate the potential demographic future of C. dentata near the historical southwestern range limit based on observations of American chestnut in these areas over the last several decades. We found suitable upland habitat with areas of high forest canopy cover occurs throughout much of the southwestern portion of the historical range and that populations of American chestnut in these areas are predicted to drastically decline over the coming decades. These results highlight the continued presence of suitable C. dentata habitat throughout the southwestern extent of its historical distribution, which should be incorporated into evaluations for future reintroduction, and emphasize the need for efforts to locate, conserve, and introduce genetic material from individuals with locally adapted genotypes into active restoration programs.
{"title":"Environmental Niche and Demographic Modeling of American Chestnut near its Southwestern Range Limit","authors":"Robert G. Laport, Zoe S. Brookover, Brian D. Christman, Nguefack Julienne, Kevin D. Philley, J. H. Craddock","doi":"10.1674/0003-0031-188.2.137","DOIUrl":"https://doi.org/10.1674/0003-0031-188.2.137","url":null,"abstract":"Abstract. The unintentional introduction and rapid spread of chestnut blight (caused by Cryphonectria parasitica (Murr.) Barr) in the early 20th century resulted in the demise of American chestnut (Castanea dentata (Marsh.) Borkh.; Fagaceae) as a major component of forest canopies resulting in negative impacts on eastern forest communities. Research efforts over the last century have documented the persistence of occasional trees and root crown/ stump sprouts throughout much of the species' historic range, providing the basis for ongoing breeding of blight-resistant trees and restoration efforts. Here we use environmental niche modeling to investigate whether environmentally suitable habitat remains for remnant trees throughout the southwestern historical range, and to evaluate the reintroduction potential of this relatively understudied part of the historical distribution. We also use stage-structured matrix projection models to investigate the potential demographic future of C. dentata near the historical southwestern range limit based on observations of American chestnut in these areas over the last several decades. We found suitable upland habitat with areas of high forest canopy cover occurs throughout much of the southwestern portion of the historical range and that populations of American chestnut in these areas are predicted to drastically decline over the coming decades. These results highlight the continued presence of suitable C. dentata habitat throughout the southwestern extent of its historical distribution, which should be incorporated into evaluations for future reintroduction, and emphasize the need for efforts to locate, conserve, and introduce genetic material from individuals with locally adapted genotypes into active restoration programs.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48611208","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}
Pub Date : 2021-07-19DOI: 10.1674/0003-0031-186.1.35
Sarah N. Brown, Rebecca M. Swab
Abstract. Restoration efforts, such as invasive species removal and establishment of native flora, can be resource intensive. Therefore, understanding the effectiveness of restoration efforts can provide land managers with the confidence to pursue restoration. This study evaluated the effects of invasive species removal and compared active revegetation to passive revegetation in enhancing forest integrity on reclaimed surface coal mine land in southeastern Ohio. Surface coal mining occurred in the area from the 1940s to the 1980s, leaving a near continuous disturbance footprint of 3704.5 ha. This study occurred within 3.6 ha of the larger disturbance footprint where mining activity ceased and reclamation with tree planting occurred in the 1960s. Due to the disturbance, the site was prone to invasive species until their removal began in 2017. In spring 2019, 2 y following invasive species removal and 1 y following seeding and planting, we completed vegetation and bloom surveys across three treatments: managed forest with invasive species removed and subsequent native plantings (planted), managed forest with invasive species removed only (unplanted), and unmanaged forest (control). Our study found vegetative species diversity, vegetative species richness, and floral species richness and bloom time were enhanced for treatments in which invasive species were removed. The planted and unplanted treatments also supported understories comprising a different community composition when compared to control plots. However, no difference was found in community composition between planted and unplanted treatments despite application of active revegetation to support understory regeneration. Overall, results after 2 y support invasive species removal to improve the herbaceous layer of an understory, with more time likely needed for planted material to establish in order to distinguish between revegetation methods.
{"title":"To Establish a Healthy Forest: Restoration of the Forest Herb Layer on a Reclaimed Mine Site","authors":"Sarah N. Brown, Rebecca M. Swab","doi":"10.1674/0003-0031-186.1.35","DOIUrl":"https://doi.org/10.1674/0003-0031-186.1.35","url":null,"abstract":"Abstract. Restoration efforts, such as invasive species removal and establishment of native flora, can be resource intensive. Therefore, understanding the effectiveness of restoration efforts can provide land managers with the confidence to pursue restoration. This study evaluated the effects of invasive species removal and compared active revegetation to passive revegetation in enhancing forest integrity on reclaimed surface coal mine land in southeastern Ohio. Surface coal mining occurred in the area from the 1940s to the 1980s, leaving a near continuous disturbance footprint of 3704.5 ha. This study occurred within 3.6 ha of the larger disturbance footprint where mining activity ceased and reclamation with tree planting occurred in the 1960s. Due to the disturbance, the site was prone to invasive species until their removal began in 2017. In spring 2019, 2 y following invasive species removal and 1 y following seeding and planting, we completed vegetation and bloom surveys across three treatments: managed forest with invasive species removed and subsequent native plantings (planted), managed forest with invasive species removed only (unplanted), and unmanaged forest (control). Our study found vegetative species diversity, vegetative species richness, and floral species richness and bloom time were enhanced for treatments in which invasive species were removed. The planted and unplanted treatments also supported understories comprising a different community composition when compared to control plots. However, no difference was found in community composition between planted and unplanted treatments despite application of active revegetation to support understory regeneration. Overall, results after 2 y support invasive species removal to improve the herbaceous layer of an understory, with more time likely needed for planted material to establish in order to distinguish between revegetation methods.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45970763","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}
Pub Date : 2021-07-19DOI: 10.1674/0003-0031-186.1.95
Jessica E. Rettig, Nicole R. Teeters, Geoffrey R. Smith
Abstract. Fish predation can structure zooplankton communities; however, the impacts of other organisms on zooplankton communities, alone or interacting with fish predation, are less known. We used two mesocosm experiments to study the impacts of Bluegill (Lepomis macrochirus) and tadpoles on temperate zooplankton communities, one with American Toad tadpoles (Anaxyrus americanus) and the other with Bullfrog tadpoles (Lithobates catesbeianus). In both experiments Daphnia (a larger bodied cladoceran) were virtually eliminated and rotifers were more abundant with Bluegill. Bluegill slightly reduced cyclopoid copepods in the American Toad experiment but not significantly, whereas cyclopoid copepods were more abundant with Bluegill in the Bullfrog experiment. Bosmina (a smaller bodied cladoceran) in the Bullfrog experiment were more abundant when Bluegill were absent, but there was no significant effect of Bluegill in the American Toad experiment. Tadpoles in general had no effect on our zooplankton communities. Our experiments confirm the influence of Bluegill on zooplankton communities, whereas tadpoles of the two anuran species had no widespread effects on zooplankton.
{"title":"Effects of the Interaction of Bluegill and Two Species of Tadpoles on Experimental Zooplankton Communities","authors":"Jessica E. Rettig, Nicole R. Teeters, Geoffrey R. Smith","doi":"10.1674/0003-0031-186.1.95","DOIUrl":"https://doi.org/10.1674/0003-0031-186.1.95","url":null,"abstract":"Abstract. Fish predation can structure zooplankton communities; however, the impacts of other organisms on zooplankton communities, alone or interacting with fish predation, are less known. We used two mesocosm experiments to study the impacts of Bluegill (Lepomis macrochirus) and tadpoles on temperate zooplankton communities, one with American Toad tadpoles (Anaxyrus americanus) and the other with Bullfrog tadpoles (Lithobates catesbeianus). In both experiments Daphnia (a larger bodied cladoceran) were virtually eliminated and rotifers were more abundant with Bluegill. Bluegill slightly reduced cyclopoid copepods in the American Toad experiment but not significantly, whereas cyclopoid copepods were more abundant with Bluegill in the Bullfrog experiment. Bosmina (a smaller bodied cladoceran) in the Bullfrog experiment were more abundant when Bluegill were absent, but there was no significant effect of Bluegill in the American Toad experiment. Tadpoles in general had no effect on our zooplankton communities. Our experiments confirm the influence of Bluegill on zooplankton communities, whereas tadpoles of the two anuran species had no widespread effects on zooplankton.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43866728","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}
Pub Date : 2021-07-19DOI: 10.1674/0003-0031-186.1.106
A. González, J. M. Long, N. Gosch, A. Civiello, T. Gemeinhardt, J. Hall
Abstract. Length-weight relationships can be useful tools for assessing fish condition. We developed these equations (W = aLb) for wild-caught age-0 (4.1–12.0 cm) Scaphirhynchus sturgeon from eight reaches spanning over 750 river km of the lower Missouri River from 2014 to 2017. We used nonlinear modeling to estimate the constant (a) and exponent (b) of the LW equation for each reach to assess potential spatial differences. We also assessed long-term temporal effects by estimating these parameters by year at Lexington reach, which is located in the middle of our sampling area and was the only reach sampled all 4 y. Constant and exponent estimates from linearized regressions varied by reach and were inversely related during the spatial analyses. Similarly, parameter estimates were also inversely related and varied among years during the temporal analysis at Lexington. To account for the relationship between constant and exponent values, we used predicted weights at 2 cm increments (4.1–12.0 cm) for the spatial analysis (by reach) and for the temporal analysis (by year). During the 2014 and 2015 spatial analyses, weights varied by size but were usually higher in Lexington and Glasgow, which were the furthest upstream reaches sampled during those years. During 2016 and 2017, Lexington was the furthest downstream reach sampled but did not consistently yield relatively high predicted weights. Temporal analysis at Lexington yielded higher predicted weights for 2014–2015 compared to 2016–2017 for higher size categories (10- and 12-cm). In general our results suggest differences in body condition among reaches and years in the lower Missouri River. Further research is needed to identify the specific mechanisms driving spatial and temporal L-W relationship differences observed and to determine if differences in predicted body conditions affect long-term survival and recruitment of age-0 Scaphirhynchus sturgeon. Currently, factors influencing age-0 Scaphirhynchus sturgeon condition and growth are unknown and this work serves to highlight knowledge gaps regarding factors influencing Scaphirhynchus sturgeon recruitment.
{"title":"Spatial and Temporal Variation in Length-Weight Relationships of Age-0 Scaphirhynchus Sturgeon in the Lower Missouri River","authors":"A. González, J. M. Long, N. Gosch, A. Civiello, T. Gemeinhardt, J. Hall","doi":"10.1674/0003-0031-186.1.106","DOIUrl":"https://doi.org/10.1674/0003-0031-186.1.106","url":null,"abstract":"Abstract. Length-weight relationships can be useful tools for assessing fish condition. We developed these equations (W = aLb) for wild-caught age-0 (4.1–12.0 cm) Scaphirhynchus sturgeon from eight reaches spanning over 750 river km of the lower Missouri River from 2014 to 2017. We used nonlinear modeling to estimate the constant (a) and exponent (b) of the LW equation for each reach to assess potential spatial differences. We also assessed long-term temporal effects by estimating these parameters by year at Lexington reach, which is located in the middle of our sampling area and was the only reach sampled all 4 y. Constant and exponent estimates from linearized regressions varied by reach and were inversely related during the spatial analyses. Similarly, parameter estimates were also inversely related and varied among years during the temporal analysis at Lexington. To account for the relationship between constant and exponent values, we used predicted weights at 2 cm increments (4.1–12.0 cm) for the spatial analysis (by reach) and for the temporal analysis (by year). During the 2014 and 2015 spatial analyses, weights varied by size but were usually higher in Lexington and Glasgow, which were the furthest upstream reaches sampled during those years. During 2016 and 2017, Lexington was the furthest downstream reach sampled but did not consistently yield relatively high predicted weights. Temporal analysis at Lexington yielded higher predicted weights for 2014–2015 compared to 2016–2017 for higher size categories (10- and 12-cm). In general our results suggest differences in body condition among reaches and years in the lower Missouri River. Further research is needed to identify the specific mechanisms driving spatial and temporal L-W relationship differences observed and to determine if differences in predicted body conditions affect long-term survival and recruitment of age-0 Scaphirhynchus sturgeon. Currently, factors influencing age-0 Scaphirhynchus sturgeon condition and growth are unknown and this work serves to highlight knowledge gaps regarding factors influencing Scaphirhynchus sturgeon recruitment.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42955240","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}
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