Seasonal weather changes determine the timing of many life-history events, including bird migration, plant flowering, and frog breeding. However, the specific set of weather cues that signal these events differs among species; some species may respond to temperature, others to rainfall. Therefore, year-to-year differences in weather can result in different responses among species, which can alter the timing of when species arrive or become active in a given area and which other species they may encounter. This could affect the outcome of species interactions, such competition or predation. The investigators of this project will experimentally manipulate colonization patterns of newly-hatched insects and amphibians in ponds. Specifically, they will vary arrival synchrony of individuals within a species as well as arrival time of species relative to one another. The goal is to determine how differences in arrival time and synchrony affect growth rates and survival of interacting species.
Understanding how seasonal variation impacts species interactions is crucial because global climate change is altering the annual activities of species throughout the world. Although many studies have documented such "phenological shifts," the consequences for species interactions -- and ultimately the biodiversity and functioning of ecosystems -- remain poorly known. To help complete this project, the investigators will hire and mentor an undergraduate student, who will be recruited from the Rice NSF AGEP program (a program that seeks to increase underrepresented groups in science). Also, the investigators are organizing a citizen scientist project to monitor the phenologies of local plants and animals, with the goal of training community members to generate data for a National Phenology Network program, called Nature's Notebook. Data contributed to this program are used by scientists, educators, policy-makers, and resource managers to understand the effects of climate change and other environmental changes.
Seasonal weather changes determine the timing of many life-history events (i.e., phenologies), including bird migration, plant flowering, and frog breeding. However, the specific suite of weather cues signaling these events differs among species (e.g., some respond to temperature, others to rainfall). Therefore, variation among years in weather patterns results in different phenological responses among species; some shift phenologies earlier, others shift later, and some show no response. This alters the timing of arrival/appearance of species relative to one another in habitats and consequently alters when species co-occur in time. This could affect the outcome of species interactions (e.g., competition, predator-prey), but little research to date has explored this. For this project, the investigators experimentally manipulated colonization patterns of newly-hatched aquatic insects and amphibians in pond habitats. Specifically, they varied arrival synchrony of individuals within a species as well as arrival time of species relative to one another to determine the individual and combined effects of these two aspects of phenology on the outcome of species interactions. Preliminary results of these experiments indicate that shifts in both aspects of phenology can have significant effects upon the strength of species interactions. For example, interactions between predator and prey become stronger (i.e., more prey are eaten) as differences in relative arrival time become greater and as prey arrival synchrony becomes lower. By using experiments such as these to determine how phenological shifts affect species interactions, we can gain a better understanding of the dynamics and sturgure of natural communities. Importantly, these experiments can also help us to understand the effects of global climate change on species because climate change is altering the phenologies of species all over the world. Through this research project and a related public outreach project, the investigators have taught research skills to a variety of people. To complete the experiments, they hired and mentored three undergraduate students, all of whom were women (an underrepresented group in science). These students were trained in a variety of research skills including experimental design, data collection, microscopy, and stable isotope sample preparation. All three of these students have pursued further research experiences through summer internship programs. The investigators also organized a citizen scientist project to monitor the timing of phenological events of local plants and animals at the Houston Arboretum. Participants in this project include members of the general public; high school, undergraduate, and graduate students; and members of local organizations including the Gulf Coast Master Naturalists and the Native Plant Society of Texas. These participants are trained in how to identify local species and their various phenological events (e.g., leaf bud bursting, flowering, fruit ripening) for the purpose of collecting scientifically-useful data. They also learn broadly about the importance of citizen science projects for understanding broad-scale and long-term patterns such as the effects of anthropogenic climate change on species' phenologies. The data collected from this project are contributed to the online database for a National Phenology Network program called Nature's Notebook. Several of the participants in the citizen science project have set up phenology monitoring projects in their own backyards and are contributing data to the National Phenology Network database.