Understanding Butterfly Phenology in a Changing Climate

Butterfly Phenology and Climate Change ENV 1004 Part 1: Evaluate the published research Use the article search tool on the Baruch library homepage to obtain the Kharouba & Veland (2015) article on the phenology of butterflies and their host plants. Kharouba, H.M. and M. Veland M. 2015. Flowering time of butterfly nectar food plants is more sensitive to temperature than the timing of butterfly adult flight. Journal of Animal Ecology 88:1311-1321. Read the article and answer the questions below. 1. What are the three objectives the authors stated in their introduction? a. The three objectives the authors stated in their introductions were: 1. to compare the phenological sensitivity to temperature of adult butterflies and plants used as nectar sources, 2. to determine whether this sensitivity differed across space and time for these taxa, and 3.to compare recent temporal shifts in phenology between butterflies and their nectar plants. 2. What are the three main types/sources of data used in this study? a. Three main types/sources of data used in this study are 1. Natural history collections data for butterfly phenology from the Canadian National Collection of Butterflies database, the Spenser Entomological Collection, and the personal and professional collections of Canadian butterfly experts. 2. Natural history collections data for plant phenology from the University of British Columbia herbarium. 3. Temperature data from the National Climate Data and Information Archive. 3. Starting on page 1314, the authors discuss the limitations of collections-based data as opposed to direct field observation. What were the limitations? How could the use of natural history collection data affect the study? a. The limitations of collections-based data as opposed to direct field observation by most of the locations having only one specimen per species so it could not be determined what part of the life cycle the single specimen represented. These could affect the study by limiting the analysis that are possible and therefore the results of the dataset. Part 2: Data Analysis Data set: Butterfly Phenology Climate Change data set for students 4. Data from how many weather stations are compiled in the Temp Data? Hint: Check out the Metadata tab!

54 weather stations are compiled in the Temp Data. 5. How many butterfly species are in the Butterfly Data? Hint: try to use the UNIQUE function. 17 butterfly species are in the Butterfly Data. 6. Create a scatterplot of average annual temperature vs. year for British Columbia. Add a trendline including its equation and R2 value (refer to the Summarizing Data lab activity to review these concepts). Include graph below. 7. Based on the trendline, how has annual temperature changed over time in British Columbia? It has steadily gotten warmer in annually in British Columbia. 8. Natural history collections are rich repositories of biodiversity data. We can use information from specimen labels to compile data about phenology. Specifically, the date that a butterfly specimen was collected represents a day during which the butterfly was in flight. Create a scatterplot of butterfly flight date vs. year. Add a trendline including its equation and R2 value.

9. How has the phenology of these butterflies shifted over time? Use the trendline equation to provide a quantitative estimate. Butterfly flight is trending towards slightly later over time, and at a rate of 0.12 days/year, p=0.31. 10. How does your estimate of phenological shift from Question 8 compare to the estimate from Kharouba and Veland that is provided in Table 1 of their article? Why is this? Kharouba and Veland calculated a shift of 0.00095 days/year. Our data show a stronger relationship to the slope. They were using different specimens and therefore they used different flight dates from the collections from which they got their butterfly data. 10. You may be surprised by your answer to questions 8 and 9. Let's consider a different relationship. Create a scatterplot of the day of year vs. mean spring temperature and add a trendline including its equation and R2 value. Include graph below.

Your preview ends here

Eager to read complete document? Join bartleby learn and gain access to the full version

Access to all documents
Unlimited textbook solutions
24/7 expert homework help

11. Repeat with mean summer temperature instead of spring. Include graph below. 12. Based on your graphs, how does the phenology of butterflies relate to temperatures in each season? Use the trendline equations to provide quantitative estimates and the R2 to describe how well the data fit the trendline. Butterfly phenology is negatively correlated with temperature. 13. Is the change in temperature the cause of the changes in phenology? Why or why not?

Temperature and phenology are correlated, but the we can not prove if temperature is the reason phenology changes. 14. Kharouba and Velland found that the host plants are more sensitive to temperature than the butterflies. Using the figure and values you derived in Question 8 as a reference, describe how a plot of the phenology of temperature-sensitive plants vs. temperature would compare to your butterfly plot. The plot of a temperature-sensitive plants vs. temperature would have a steeper slope and be more correlated. 15. How would you recognize if a phenological mismatch were possible between butterflies and their host plants? Describe how this would look when plotted. The potential for an ecological mismatch would be shown when the slopes of the butterfly flight data vs. temperature plot anf the plant phenology vs. temperature plot were marked differently. Their trendlines would be opposite. 16. During which periods of time were there the greatest numbers of collected specimens? When were there the least? How might this impact the analysis? 1930 -1940, 1950 - 1960, and 2000. This might impact the analysis by not providing the full picture of how butterflies respond to temperature during different cold and warm temperatures.

Lab #3 Butterfly Phenology

Related Documents