PS 30-81 - Reproductive timing at two temporal scales affects mating opportunity in a long-lived perennial species

Thursday, August 11, 2016
ESA Exhibit Hall, Ft Lauderdale Convention Center
Amy M. Waananen1, Gretel Kiefer2, Jennifer L. Ison3 and Stuart Wagenius2, (1)Chicago Botanic Garden, Glencoe, IL, (2)Chicago Botanic Garden, (3)Ecology and Evolution, University of Illinois at Chicago, Chicago, IL

An individual’s reproductive timing may play large role in determining its opportunity to interact with potential mates and therefore, its reproductive fitness. Timing effects on individuals may increase with the degree of population synchrony. If a population is highly synchronous, flowering in accordance with the population’s peak flowering would result in more mating opportunities than flowering off peak. Likewise, for perennials which flower in multiple seasons, flowering in a high-flowering year will imply more potential mating interactions than a low-flowering year. Reproductive timing within and between years may both affect the long-term mating opportunity of individuals, but their influence has seldom been considered simultaneously. We used a null modeling approach with an 11-year individual flowering phenology dataset of the long-lived perennial, Echinacea angustifolia, to evaluate the relative importance of timing within and between years on long-term individual mating opportunity. We also related mating opportunity to reproductive effort, measured as time flowering during the study period, to address how the length of time individuals reproduce affects their opportunity for mating success.


We found high degrees of synchrony both within and between years, leading us to hypothesize that timing at both scales impacts mating opportunity. We found that timing both within and between seasons impacted individuals’ mating opportunity. Our results allow us to quantify the relative importance of timing at each scale and preliminary analysis indicates that aynchronous timing between years caused a 5% decrease in mating opportunity. Asynchronous timing within years had double the impact of between-year timing, resulting in 10% loss of mating opportunity. Individuals that flowered longest had the greatest mating opportunity. However, as number of years flowering increased, flowering was more likely to coincide with both high- and low-flowering years, resulting in intermediate mating opportunity per unit time.