Progress 01/15/16 to 01/14/17
Outputs
Target Audience:The research efforts during this reporting period reached collaborators at academic and governmental research institutions. Networking and dissemination of results from the last year of this project were achieved at the North America Forest Insect Work Conference, the International Congress of Entomology, the Annual Gypsy Moth Review meeting of the National Gypsy Moth Management Board, and the Virginia Association of Forest Health Professionals. State and federal stakeholders in gypsy moth management as well as those generally interested in forest health were reached at these meetings. Organizers from the Slow-the Spread program were also present at these meetings and I recently joined the Slow the Spread Foundation Technical Committee. Undergraduate students were an integral part of the research team during all stages of the project. Six students participated in gypsy moth rearing and data collection (twostudents from underrepresented groups). These students also conducted independent projects using gypsy moth. One co-advised graduate student from Virginia Commonwealth University continued data collection and collaborated with undergraduate projects. Changes/Problems:I used the advanced programming capabilities of environmental chambers obtained in my start-up package to simulate current and future climates for gypsy moth, including changes over time due to global warming and changes over space as the invasion reaches new southern extremes. My initial attempts at these experiments were impacted by a catastrophic chamber failure, a year with poor larval hatching success, and difficulties selecting the appropriate thermal regimes. After intense efforts, I think we have overcome the technical hurdles and we successfully evaluated the ability of the chambers to replicate natural growing conditions. We plan to use the U.S. Climate Normals Database in future experiments, which provides 30-year averages for temperature and other weather variables for each hour and day of the year. This will remove much of the problematic variation in local temperature that we have experienced in the past. What opportunities for training and professional development has the project provided?The opportunities provided by a NIFA fellowship/grant conversion have included the development of my own independent research lab at University of Richmond, with the proposed research launching my laboratory. I have continued to network with forest entomologists, build new collaborations, strengthen my collaborative work as an independent scientist, and extend my professional relationships with state and federal managers. I have provided training and professional development opportunities to one senior technician and one graduate student, as well as six undergraduate students. How have the results been disseminated to communities of interest?These results have been presented and discussed as invited oral presentations at one state meeting (Virginia Association of Forest Health Professionals), two national meetings (North American Forest Insect Work Conference and Annual Gypsy Moth Review) and one international meeting (International Congress of Entomology). What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Impact Statement This research examines spread at the southern invasion front of a highly destructive forest pest in North America, the gypsy moth. My projects have focused on understanding the role of physiological tolerances and local adaption at the range edge of invasive species. Together my results indicate the potential for local adaptation for survival and development of gypsy moth under higher temperatures at the southern invasion front. In this yearI focused my efforts on publishing the results from Aim 1 and finishing data collection on Aim 2, which extended into a second year to understand differences in overwinter survival based on southern climates. Under Aim 3, I continued using growth chamber experiments with custom temperature regimes to test gypsy moth growth and development under current and future southern climates. The ability for environmental chambers to replicate past and future temperature conditions remains an under-utilized tool for studying the effects of climate change. Generally, my research this year found that southeastern climates do not pose a barrier for the survival of gypsy moth larval, but there are sublethal effects on performance. Southern populations show some evidence of improved performance under heat stress, but not enough to overcome reductions in viability under southern heat. This work contributes to the management of North American forests by assessing the ability of a damaging insect to adapt to climatic environments at an invasion front and measuring the potential for climate change to facilitate or limit future spread. Objectives Progress: 1) Quantify geographic variation in lethal and sublethal effects of supraoptimal temperatures on gypsy moth development and life history parameters. a. Major activities completed/experiments conducted: The constant temperature experiment was completed in the previous reporting year (2015). An additional experiment was conducted with undergraduate students to test for differences in metabolic rate between northern (Massachusetts) and southern (Virginia coastal plain: CP) gypsy moth populations. Gypsy moths from the northern and southern populations were acclimated in constant temperature conditions of either 20°C or 30°C, and metabolic rate of third instar gypsy moth larvae was measured at either 20°C, 28°C, 30°C, and 35°C, which represents a range from the lower acclimation temperatures, the developmental time optimum, and an extreme supraoptimal temperature. b. Data collected: Metabolic rate was measured as CO2 production using a climate-controlled respirometry system. c. Discussion of the results: For larvae across acclimation temperatures and populations, the metabolic rate increased with increasing temperature. For the larvae acclimated to 20°C, the northern population tended to have a higher metabolic than the southern population. For the larvae acclimated to 30°C, both populations had similar metabolic rates. d. Key outcomes: The manuscript from the constant supraoptimal temperature study was published (2017) with two undergraduate co-authors. The metabolic rate experiment is currently in final preparation for publication with two undergraduate co-authors. 2) Test for adaptive change in life history traits in response to environmental temperature. a. Major activities completed/experiments conducted: The common garden experiment was completed in this reporting year with the addition of an egg viability experiment and an analysis of larval development time using degree day calculations. Larval and pupal development time wereanalyzed separately using degree day calculations. In the egg overwintering experiment, egg masses from the common garden experimentin summer 2015 were split between overwintering in refrigerated lab storage (ideal conditions) and overwintering in the rearing location(mountains or coastal plain). Egg mass viability of each population was compared between overwintering locations. b. Data collected: For the egg overwintering experiment, we counted: 1) the number of hatched eggs/larvae, 2) the number of unhatched, fertilized larvae, and 3) the number of unfertilized larvae. Developmental degree days were calculated based on the environmental temperature and developmental dates. c. Discussion of the results: In the egg overwintering experiment, the WV and NY populations had reduced egg viability when overwintered in the coastal plain, but not when overwintered in the mountains. The CP population did not have reduced egg viability when overwintered in the coastal plain, but did have overall lower viability than the WV and NY populations. This suggests that there may be local adaptation of the coastal plain population to the coastal plain environment, but that this adaptation may come at the cost of reduced egg viability. The developmental degree day analysis shows that supraoptimal temperatures affect the development time of gypsy moths in natural settings and that temperatures above the developmental time optimum do prolong development time even for short periods of time over the course of development. Our results also suggest that the optimum development time for the pupal stage may be slightly higher than for the larval stage, which is consistent with the pupal stage happening later in the summer when temperatures are generally warmer. d. Key outcomes: The manuscript from the common garden experiment is currently in final preparation for submission to Biological Invasions with six undergraduate co-authors. 3) Assess the potential for further southern spread of the gypsy moth under current and future climate scenarios. a. Major activities completed/experiments conducted: The historic temperature experiment was completed in the previous reporting year (2015) and data analysis was finished this year. A supplementary experiment was conducted in this reporting year to compare the growth and development of lab straingypsy moth larvae outside, in a chamber replicating outside temperature at 30 minute intervals, and in a chamber on a diurnal cycle using daily average outside day and night temperatures. The goal of this experiment was to validate the use of environmental temperature chambers as an alternative to rearing outdoors. b. Data collected: The developmental metrics measured include: the duration of each instar, the total larval duration, a measure of growth near the middle of development (3-4 instar), a measure of growth later in development (4-5 instar), pupal mass, pupal duration, and total development time (hatch to adult). c. Discussion of the results: Preliminary results indicate that there was no difference in any developmental metric or growth metric between replicated chambers. There was also no difference in any developmental metric between any of the three temperature regimes. Growth was slightly greater in the larvae reared outside than in either chamber temperature treatment. Gypsy moths reared in either type of environmental chamber took slightly longer to reach all developmental milestones than those reared outside. However, the mass of all male pupae were similar regardless of treatment. These results indicate that replicating outdoor temperatures in 30 minute intervals results in the same developmental and growth outcomes as only replicating daily and nightly average temperatures. They also indicate that something other than temperature accounts for the differences between the chamber treatments and the outside treatment. d. Key outcomes: A manuscript combing the historical temperature experiment and the indoor-outdoor comparison experiment is currently in preparation with one undergraduate co-author. These experiments have shifted my thinking for setting up future studies mimicking real temperature data.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2017
Citation:
Thompson, L.M., T.M. Faske, N. Banahene*, D. Grim*, S.J. Agosta, D. Parry, P.C. Tobin, D.M. Johnson, and K.L. Grayson. 2017. Variation in growth and developmental responses to supraoptimal temperatures near latitudinal range limits of gypsy moth (Lymantria dispar (L.)), an expanding invasive species. Physiological Entomology. doi:10.1111/phen.12190
* = undergraduate author
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2016
Citation:
Grayson, K., L. Thompson, T. Faske, P. Tobin, C. Friedline, A. Eckert, D. Parry, D. Johnson. 2016. Invited Symposium Presentation. The opening and closing of climatic envelopes in the gypsy moth invasion of North America. International Congress of Entomology. Orlando, FL.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2016
Citation:
Thompson L., T. Faske, S. Agosta, D. Parry, P. Tobin, D. Johnson, and K. Grayson. 2016. Invited Presentation. Population variation in gypsy moth performance at supraoptimal temperatures across the southern invasion front. The Annual Review of the National Gypsy Moth Management Board. Columbus, OH.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2016
Citation:
Grayson, K., L. Thompson, T. Faske, D. Parry, D. Johnson, and P. Tobin. 2016. Invited Symposium Presentation. Can Gypsy Moth Stand the Heat?: Performance at the Southern Invasion Front. North American Forest Insect Work Conference. Washington, D.C.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2017
Citation:
Grayson, K., L. Thompson, and T. Faske. 2017. Invited Presentation. Thermal Performance and the Southern Invasion of the Gypsy Moth. Virginia Association of Forest Health Professionals. Glen Allen, VA.
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Progress 01/15/15 to 01/14/17
Outputs
Target Audience:The efforts during the entirety of this research period (Janaury 2014 - January 2017) reached a variety of academic and governmental organizations. Research under this award started as a postdoctoral fellowship from 2014 - 2015 before conversion to a standard grant in 2015. Networking and dissemination of results occurred at the following conferences: USDA Interagency Research Forum on Invasive Species (2014) World Congress of the International Union of Forest Research Organizations (2014) Annul Gypsy Moth Review meeting of the National Gypsy Moth Management Board (2014, 2015, 2016) Ecological Society of America (2015 and upcoming in 2017) North America Forest Insect Work Conference (2016) International Congress of Entomology (2016) Virginia Association of Forest Health Professionals (2017) In addition to academic researchers, state and federal stakeholders in gypsy moth management as well as those generally interested in forest health were reached at these meetings. I regularly communicated my results with leading managers of the Slow-the Spread program, particularly at the Annual Gypsy Moth review meeting. I was recently invited to join the Slow the Spread Foundation Technical Committee and attended my first Operations and Technical meeting as an advisor. As a new faculty member at University of Richmond, a primary undergraduate institution, providing mentoring and research opportunities to undergraduate students is a critical component of my job. I am passionate about working with undergraduate students and started integrating students into my research when the project started at Virginia Commonwealth University. These students have contributed to the data collection of the proposed research as well as conducted their own independent research projects. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?The opportunities provided by a NIFA fellowship/grant conversion have included the development of my own independent research lab at University of Richmond, with the proposed research launching my laboratory. I have continued to network with forest entomologists, build new collaborations, strengthen my collaborative work as an independent scientist, and extend my professional relationships with state and federal managers. I have provided training and professional development opportunities to one senior technician and one graduate student, as well as sixteen undergraduate students total.I am passionate about working with undergraduate students and started integrating students into my research when the project started at Virginia Commonwealth University. These students have contributed to the data collection of the proposed research as well as conducted their own independent research projects. The following undergraduate students have worked on this project: 2014 (VCU): Katrina Kahil, Taylor Price, Joey Neale, Sharon Woosley, Dominqiue Grimm, Trevor Faske (continued as a MS student) 2015 (UR): Melisa Quiroga-Herrera, Amber Yang, Nana Konadu Banahene, Kayla Sherman, Andrew Levorse 2016 (UR): Nana Konadu Banahene, Kelly Brosko, Sarah Timko, Carolyn May, Noah Hillerbrand, Salem Salem How have the results been disseminated to communities of interest?Networking and dissemination of results occurred at the following conferences: USDA Interagency Research Forum on Invasive Species (2014) World Congress of the International Union of Forest Research Organizations (2014) Annul Gypsy Moth Review meeting of the National Gypsy Moth Management Board (2014, 2015, 2016) Ecological Society of America (2015 and upcoming in 2017) North America Forest Insect Work Conference (2016) International Congress of Entomology (2016) Virginia Association of Forest Health Professionals (2017) In addition to academic researchers, state and federal stakeholders in gypsy moth management as well as those generally interested in forest health were reached at these meetings. I regularly communicated my results with leading managers of the Slow-the Spread program, particularly at the Annual Gypsy Moth review meeting. I was recently invited to join the Slow the Spread Foundation Technical Committee and attended my first Operations and Technical meeting as an advisor. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Impact Statement Invasive species threaten native ecosystems, agriculture, and forestry and advanced quantitative methods are necessary to understand current risks of spread as well as the potential for future shifts in distribution under environmental change. Introduced from Europe in 1869 to Massachusetts, the gypsy moth now ranges from Minnesota to North Carolina. In some areas, the gypsy moth continues to spread rapidly across the landscape, while other areas are static or seeing range retraction. As gypsy moth continues to encounter widely divergent environmental conditions at range margins, shifts in physiological tolerance may have large impacts on invasion potential and future spread. This research investigated the role of thermal physiology and local adaptation in the invasion process. I conducted a series of laboratory and field experiments to understanding growth and development of gypsy moth at the southern range edge. We quantified the upper temperature bounds for gypsy moth survival and found moderate evidence for improved performance in southern populations under temperature extremes. In our field experiment, we found that spring and summer temperatures did not impact larval survival, but reduced caterpillar size and the number of eggs laid. Mild winter temperatures in the southeast also reduced overwinter egg viability. We used growth chamber environments to simulate current and future environments in the southeast, an important research tool since we cannot transport an invasive species into areas in advance of the invasion front to test performance. Together, this work provides a regional analysis of differences in thermal performance across gypsy moth life stages. This information directly informs the future spread potential of the gypsy moth in the southeastern United States. Objectives Progress: 1) Quantify geographic variation in lethal and sublethal effects of supraoptimal temperatures on gypsy moth development and life history parameters. a. Major activities completed/experiments conducted: We first compared the performance of lab and wild collected gypsy moth reared on foliage compared to artificial diet. We then performed a series of constant temperature experiments using populations spanning the latitudinal distribution of the gypsy moth invasion in North America. We compared the performance of these populations at multipleconstant optimal and supraoptimal temperatures. Additionally, we conducted another experiment to test for differences in metabolic rate between northern and southern gypsy moth populations and compare the role of acclimation versus adaptation. b. Data collected: Measurements of performance include: survival, growth rate, developmental time to pupation, duration of the pupal stage, pupal mass, and percent adult emergence. Metabolic rate was measured as CO2 production using a climate-controlled respirometry system. c. Discussion of the results: Gypsy caterpillars reared on foliage had higher survival and faster development rates, with smaller differences among populations. In the constant temperature experiments, performance and fitness generally followed the expected latitudinal pattern. We found interactions between populations in acclimation of metabolic rate to temperature. Together our results indicate the potential for local adaptation for survival and development of gypsy moth under supraoptimal temperatures. d. Key outcomes: Two manuscripts have been published from this aim with undergraduate co-authors. 2) Test for adaptive change in life history traits in response to environmental temperature. a. Major activities completed/experiments conducted: I conducted a common garden field experiment using 3 populations (Coastal Virginia, WV, NY) at 2 rearing locations to assess the local adaptation of the populations to climatic conditions across the southern range edge. This experiment spanned a second year to measure overwintering success of eggs in these two environments. b. Data collected: We measured survival, growth, and development during the larval and pupal period. We measured fecundity and the viability of the egg mass after overwintering. c. Discussion of the results: We found significant performance differences between sites, with gypsy moths reared in the mountain site growing to larger sizes than the coast plain site. Phenotypic differences between populations were not as pronounced as in growth chamber experiments under constant conditions. Northern populations had reduced egg viability when overwintered in the coastal plain, but not when overwintered in the mountains. We found evidence of local adaptation of the coastal plain population to the warmer environment. d. Key outcomes: The manuscript from the common garden experiment is currently in final preparation for submission to Biological Invasions with six undergraduate co-authors. 3) Assess the potential for further southern spread of the gypsy moth under current and future climate scenarios. a. Major activities completed/experiments conducted: Obtaining growth chambers capable of custom programming with realistic temperature profiles enabled me to empirically test the effect of historic extreme temperature regimes at the southern invasion front and future temperature regimes as predicted under climate change on gypsy moth growth and development. A second experiment was conducted to compare the growth and development of lab strain gypsy moth larvae outside, in a chamber replicating outside temperature at 30 minute intervals, and in a chamber on a diurnal cycle using daily average outside day and night temperatures. The goal of this experiment was to validate the use of environmental temperature chambers as an alternative to rearing outdoors. b. Data collected: Under this objective we compared the performance of the CP, WV, NY, and labpopulations of gypsy moth at 4 temperature regimes, 3 historic and 1 predicted. Historic temperatures came from the hottest and coldest years in the coastal plain of Virginia (2005, 1997) and the hottest year in the mountains of West Virginia (1993). The climate change scenario temperatures were calculated by adding 1.7°C to each temperature point from the hottest coastal plain year (2005). Performance measures were the same as the experiment in objective 1. c. Discussion of the results: There were significant differences among populations at the different temperature regimes but the biological significance is small. The warmest year in the coastal plain and the climate change scenario did not have lethal or substantial sublethal effects for any of the populations tested here.Preliminary results indicate that there was no difference in any developmental metric or growth metric between replicated chambers (two chambers for each temperature regime). These results indicate that replicating outdoor temperatures in 30 minute intervals results in the same developmental and growth outcomes as only replicating daily and nightly average temperatures. d. Key outcomes: A manuscript combing the historical temperature experiment and the indoor-outdoor comparison experiment is currently in preparation with one undergraduate co-author. We plan to use the U.S. Climate Normals Database in future experiments, which provides 30-year averages for temperature and other weather variables for each hour and day of the year. This will remove much of the problematic variation in local temperature that we experienced in these first experiments.
Publications
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Progress 01/15/15 to 01/14/16
Outputs
Target Audience:The research efforts during this reporting period reached collaborators at academic and governmental research institutions. Networking and dissemination of results from the second year of this project were achieved at the Ecological Society of America 100th Annual Meeting and the Annual Gypsy Moth Review meeting of the National Gypsy Moth Management Board. State and federal stakeholders in gypsy moth management as well as those generally interested in forest health were reached at these meetings. Organizers from the Slow-the Spread program were also present at these meetings. Undergraduate students were an integral part of the research team during spring and summer data collection. Five students participated in gypsy moth rearing and data collection (three students from underrepresented groups). Four of these students completed an independent study project on gypsy moth during the summer. These students will be co-authors on all related publications. One co-advised graduate student from Virginia Commonwealth University began data collection with the undergraduates this spring and started as a Master's student in fall 2015 studying gypsy moth genetics at the southern range edge. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?The opportunities provided by a NIFA fellowship have included the development of my own independent research lab at University of Richmond, with the proposed research launching my laboratory. I have continued to network with forest entomologists, build new collaborations, strengthen my collaborative work as an independent scientist, and extend my professional relationships with state and federal managers. How have the results been disseminated to communities of interest?The results of this research have been presented and discussed at two national meetings: a contributed poster with undergraduate co-authors and an invited oral presentation. What do you plan to do during the next reporting period to accomplish the goals?All experiments planned to address the objectives of the project have been completed during this reporting period. In the next reporting period, I will collect the remaining egg mass data (fecundity, viability, etc.) and prepare the results for publication.
Impacts
What was accomplished under these goals?
Impact Statement In this second year of the project, I focused my efforts on comparing gypsy moth populations and physiological responses in these two regions. To do this I conducted 3 experiments: 1) a follow up constant temperature experiment to the one reported last year narrowing the upper limit temperature range and using populations specific to the southern invasion front, 2) a field experiment to examine the survival and successful development of gypsy moth at mountain and coastal plain locations in Virginia, and 3) a laboratory experiment exposing gypsy moth to historic extreme temperatures of the mountain and coastal plain regions of West Virginia and Virginia as well as a climate change predicted temperature regime. All three experiments were conducted using gypsy moth lineages from the coastal plain of Virginia (CP), the mountains of West Virginia (WV), upstate New York (NY), and the New Jersey Standard Strain (NJSS) reared by the Animal and Plant Health Inspection Service Laboratory (Buzzards Bay, MA). Objectives Progress: 1) Quantify geographic variation in lethal and sublethal effects of supraoptimal temperatures on gypsy moth development and life history parameters. a. Major activities completed/experiments conducted: During the previous reporting year (2014), a constant temperature experiment was conducted using four populations spanning the latitudinal distribution of the gypsy moth invasion in North America (Quebec, upstate New York, North Carolina, and the lab strain, NJSS). In that experiment, we compared the performance of these populations at three constant rearing temperatures: 28°C, 31°C, and 34°C. For experiments this reporting period, I was able to obtain a lineage of gypsy moths from the West Virginia mountains and another from the coastal plain of Virginia. Informed by the results from last reporting period, I chose a narrower range of constant temperatures to test upper thermal limits of these populations of gypsy moth. Our experiment this year tested the survival and fitness of 3 populations (CP, WV, NJSS) at a constant 26°C, 29°C, and 32°C. b. Data collected: In this follow up experiment, we compared the performance of the CP, WV, and NJSS gypsy moth populations at three constant rearing temperatures: 26°C, 29°C, and 32°C. Measurements of performance include: survival, growth rate, developmental time to pupation, duration of the pupal stage, pupal mass, and percent adult emergence. All larvae were reared in growth chambers on artificial diet (Frontier, Lepidoptera diet, USDA formula). c. Discussion of the results: In this experiment no individuals in any population survived past the 5th instar at a constant 32°C. Survival among populations was similar at 26°C and 29°C, however, performance and fitness generally followed the expected latitudinal pattern seen in the prior experiment, with CP doing better at 29°C than WV and the NJSS lab population doing the best. Differences among populations were more pronounced for males than for females. d. Key outcomes: One manuscript with undergraduate co-authors is in preparation using the results of the experiment addressing this objective. 2) Test for adaptive change in life history traits in response to environmental temperature. a. Major activities completed/experiments conducted: The gypsy moth invasion front is advancing steadily in the mountain region of Virginia and West Virginia, but is contracting in the coastal plain of Virginia. Under this objective, I conducted a common garden field experiment using 3 populations (CP, WV, NY) at 2 rearing locations to assess the local adaptation of the populations to weather conditions across the southern range edge. b. Data collected: Egg masses from CP, WV, and NY populations were split in half, with one set of siblings overwintered in the Virginia mountains (Mountain Lake Biological Station, 60 miles from WV source location) and one set overwintered on the University of Richmond campus (90 miles from Virginia coastal plain source location). After hatching, larvae were reared on northern red oak (Quercus rubra) foliage in screened containers in outdoor pavilions. At both sites we measured survival, growth rate, developmental time to pupation, duration of the pupal stage, pupal mass, and percent adult emergence. After adult emergence, adults were paired (same rearing location and source population) and mated. After egg laying, all adult moths were preserved individually in a -80°C freezer. Egg masses produced in these experiments will hatch in Spring 2016 at which time egg viability and fecundity will be measured. c. Discussion of the results: We found significant performance differences between sites, with gypsy moths reared in the mountain site growing to larger sizes than the coast plain site. Phenotypic differences between populations were not as pronounced as in growth chamber experiments under constant conditions. d. Key outcomes: The results of this objective were presented at the Ecological Society of America 100th Annual meeting and at the Annual Gypsy Moth Review of the National Gypsy Moth Management Board. Results from this objective are in preparation for publication with undergraduate co-authors. 3) Assess the potential for further southern spread of the gypsy moth under current and future climate scenarios. a. Major activities completed/experiments conducted: Moving to the University of Richmond allowed for the use of four highly programmable growth chambers. I utilized this technology to empirically test the effect of historic extreme temperature regimes at the southern invasion front and future temperature regimes as predicted under climate change on gypsy moth growth and development. b. Data collected: Under this objective we compared the performance of the CP, WV, NY, and NJSS populations of gypsy moth at 4 temperature regimes, 3 historic and 1 predicted. Historic temperatures came from the hottest and coldest years in the coastal plain of Virginia (2005, 1997) and the hottest year in the mountains of West Virginia (1993). Hottest and coldest year classifications were defined based on the methods of Tobin et al. (2014) using the number of hours above optimal gypsy moth development temperature (28°C) during the period of gypsy moth activity for the year (hatching to adulthood), with the hottest year having the most and the coldest year having the fewest. The climate change scenario temperatures were calculated by adding 1.7°C to each temperature point from the hottest coastal plain year (2005). Performance measures were the same as the experiment in objective 1. c. Discussion of the results: There were significant differences among populations at the different temperature regimes but the biological significance is small. The warmest year in the coastal plain and the climate change scenario did not have lethal or substantial sublethal effects for any of the populations tested here. Differences in pupal mass are more pronounced in females than in males, contrary to the results of the constant temperature experiment in the first objective. d. Key outcomes: Improved technology has shifted my thinking towards empirical testing of climate change predictions and has opened up an avenue for future climate simulation studies in the gypsy moth and possibly other species. Preliminary results of this objective were presented at the Annual Gypsy Moth Review of the National Gypsy Moth Management Board. The results are currently being prepared for publication with undergraduate co-authors.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2015
Citation:
Grayson, K.L., D. Parry, T. Faske*, A. Hamilton*, P.C. Tobin, S.J. Agosta, & D.M. Johnson. 2015. Performance of wild and laboratory-reared gypsy moth (Lepidoptera: Erebidae): A comparison between foliage and artificial diet. Environmental Entomology. 44: 864-873.
* = undergraduate author
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2015
Citation:
Grayson, K.L., L.M. Thompson, T. Faske*, N.K. Banahene*, A. Levorse*, M. Quiroga-Herrera*, A. Yang*, D. Parry, P.C. Tobin, D.R. Gray, & D.M. Johnson. 2015. Poster Presentation. Performance of the gypsy moth at supraoptimal temperatures at the southern invasion front. Ecological Society of America 100th Annual Meeting. Baltimore, MD.
* = undergraduate author
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2015
Citation:
Grayson, K., L. Thompson, & T. Faske. 2015. Invited Oral Presentation. Performance of Gypsy Moth Under Historic, Current, and Future Temperatures at the Southern Invasion Front. Annual Gypsy Moth Review of the National Gypsy Moth Management Board. Virginia Beach, VA.
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