2015 – Sevilleta Research Experience for Undergraduates Program

Adam Rodriguez

Adam’s 2015 REU project was “Thermal tolerances and the effect of body temperature on behavioral and physiological performances in the Mountain Spiny Lizard, Sceloporus jarrovi.”

The fitness of an ectothermic species is necessarily dependent on temperature. Most behavioral and physiological processes occur at optimal levels over a narrow range of body temperatures, known as the optimal temperature range. Outside this range of temperatures, above or below, performance levels drop rapidly. We investigated the relationship between the thermal environment and certain behavioral and physiological performances, in Yarrow’s Spiny lizard (Sceloporus jarrovi). We measured: 1) the selected temperature (Tsel) when the lizards are placed in thermal gradients, which is the temperature that the lizards maintain to maximize all performances; 2) critical thermal limits (CTmax and CTmin), displaying the thermal breadth for any measured performance; 3) the voluntary maximum temperature (VMT) that the lizards could withstand, which can be used to predict a change in the range of this species as the climate change affects the distribution of this species in the wild; and 4) energy assimilation, an important physiological trait for maintenance and growth of the animal. While Tsel, CTmax, and CTmin two performances which have been previously measured in this species (, we found that our sample of the species sampled individuals could withstand a lower CTmin, as well as a higher CTmax. From our energy assimilation experiment, we will produce a performance curve, and relate it to behavioral performance curves produced by Martin S. Beal 2014, to have a better understanding of different ecological scenarios (e.g., competition, perceived predation threat and foraging opportunities) while in varying thermal environments.

Adam is a current undergraduate student at SUNY, University of Albany.

Ann O’Brien

Ann’s 2015 REU art project was “Hand papermaking on the Sevilleta National Wildlife Refuge.”

I spent the summer learning papermaking processes utilizing fibers available on the Sevilleta National Wildlife Refuge. Paper is one of the many transient objects surrounding us every day. In general it offers few associations to its source materials or environment. To challenge this I wanted to create paper that is tightly knit into the daily life and research on the Sevilleta National Wildlife Refuge and more importantly to the land itself.

Ann graduated in 2016 with a B.F.A. in Metals from SUNY, New Paltz. She is currently working as an intern at American Conservation Experience.

Aulaya Williams-Grant

Aulaya’s 2015 REU project was “Small mammal response to prescribed fire in the Northern Chihuahuan desert.”

It was widely thought not long ago that wildland fires were detrimental to the vegetation, animals, and even abiotic factors that encompass that location. However, fire ecology has been shown to have substantial benefits to the environment. Wildland fires are a naturally occurring process and serve the very important purpose of periodically regenerating the environment by burning vegetation and allowing those plants to be rejuvenated. The mammals and reptiles of the desert depend on this renewal, and therefore, the fire benefits the entire community. The aim of this study is to examine the short term effects of prescribed fire upon the plants and small mammals living in the northern Chihuahuan desert of central New Mexico. Four 16-ha plots were used in this study, two 16 hectare plots that were burned in March 2015 and two 16-ha control plots. Pre and post fire (three months following treatment) measurements of plant and animal communities were conducted. My goal is to assess the responses of these communities to low intensity fires. Every species, with the exception of Dipodomys spectabiis on the control plots, displayed some degree of an abundance decline. The significant abundance changes can be attributed to vegetation changes due to fire and abnormal precipitation, which was unusually high for the year.

Aulaya is currently an undergraduate student at Tuskegee University.

Briana Becerra

Briana’s 2015 REU project was “A quantitative study on Juniper and Pinyon biomass within the Sevilleta Wildlife Refuge.”

Briana graduated in 2016 with a B.S. in Environmental Science, Technology, and Policy from California State University, Monterrey Bay.

Brittney White

Brittney’s 2015 REU project was “Comparative morph demographics in two species of polymorphic lizards.”

Color polymorphisms are represented in numerous species. In some species such Uta stansburiana these color polymorphisms are associated with alternative reproductive strategies, each of which has equivalent fitness. It has been shown that there are three male strategies which oscillate in frequency. The frequency of the strategies that are occurring at the Sevilleta National Wildlife Refuge were determined and the plausible correlations that the various strategies may have physiologically and ecologically. We found that both Urosaurus and Uta have multiple morphs at the Sevilleta. The Uta population contains the ancestral 3 male morphs and 2 female morphs and the frequency is similar to Southern populations of NM. Our survey of Urosaurus did not uncover the 3 known male morphs. We found only green and blue males and no orange throated males. Our surveys did uncover what appears to be two female morphs or just the variation of a single morph when it is either gravid or not gravid. Because Urosaurus is not as well understood as Uta it is hard to determine genetic correlations to the phenotype but it appears that a morph of Urosaurus has been lost at the Sevilleta and further analysis that includes genotyping could offer more insight into the mechanisms behind the loss and how diverged this population of Urosaurus is from other populations of the species.

Britt graduated in 2016 with a B.S. in Biology from the University of New Mexico.

Jeanne O’Conner

Jeanne’s 2015 REU art project was “Art in ecology: A walk on the wild side.”

The term environmental art refers to a constantly evolving worldwide movement. It is an interdisciplinary research based contemporary art practice. Eco-artists have a range of goals that may include but certainly is not limited to, raising awareness about environmental issues, reclaiming damaged eco-systems, using eco-friendly materials, exploring earth forces, and re-envisioning our relationship with nature. This field helps to bridge the gap between art and science, while creating a dialogue with the community through public outreach. I consider myself to be a part of this movement, aiming to improve human interactions with the environment.

Jeanne graduated in 2015 with a B.F.A. in Metals from SUNY, New Paltz. She is currently an intern with the National Park Service.

Lesly Huerta

Lesly’s 2015 REU project was “Macroinvertebrate resilience in drought conditions.”

Springs in the desert can host an extremely diverse aquatic community, one that is poorly studied but can serve as an indicator of the ecosystems health. Drought conditions have been recognized as a significant driver in the aquatic community composition, often changing the communities dynamic by eliminating sensitive taxa. Extreme drought conditions can result in shifts in the macroinvertebrate community resulting in long-term impacts that can have devastating effects on the ecology of the water systems present this microhabitat. The invertebrates inhabiting these aquatic environments contain different adaptations making certain species more resistant or resilient to drought conditions. In order to better understand the effects that drought conditions have on the macroinvertebrate communities, I conducted a study at the Sevilleta National Wildlife refuge, in New Mexico to determine if there was a connection between drought and the diversity of invertebrates between the years 2010, 2013-2015. Although due to a lack of data on abundance in 2010 and 2013, I was unable to look at the difference in diversity, and instead looked at taxonomic richness. I collected data from 15 sites, and by using data collected in previous years, I was able to compare the diversity and abundance of the invertebrates inhabiting the springs and wells found on the refuge, and whether they were able to return to their pre-drought conditions. After performing a univariate test there was found to be no significant difference between the taxonomic richness between 2010, 2013-2015, but a marginal significance between taxonomic richness between the springs and drinkers found on the Sevilleta (Univariate Analysis of Variance, p=.004). Even though, the research project only focuses on a number of springs and wells found at the Sevilleta, the results can have implications for many dry regions, providing a glimpse into the future of desert ecosystems.

Lesly graduated with her B.S. in Biology from California State University, Channel Islands in 2016.

Maia Persche

Maia’s and Matee’s 2015 REU project was “Gray Vireo (Vireo vicinior) nesting success and site selection in response to prescribed fire on the Sevilleta National Wildlife Refuge.”

The Sevilleta National Wildlife Refuge, located in central New Mexico, is unique among protected areas in the southwestern United States. Five major biotic zones intersect on the refuge, creating a biologically diverse ecosystem that has attracted scientists internationally. One such biome, the Piñon-Juniper woodland, provides breeding habitat for the Gray Vireo (Vireo vicinior), a little-known songbird listed as threatened within the state of New Mexico. Limited information is available in this part of the state regarding the vireo’s nesting success and even less is known about the species response to low-intensity prescribed fire. The objective of our project is to fill in the knowledge gap in the species breeding biology and provide relevant data to inform future management activity in Gray Vireo habitat. We conducted point surveys, nest monitoring, and vegetation measurements in three locations within the Los Piños Mountains on the eastern portion of the Sevilleta NWR. Preliminary results suggest that Gray Vireos avoid an area of the study site that was burned this spring, despite the apparent availability of suitable nesting habitat. Data from previous field seasons, for a total of five years, will be compiled and analyzed to produce a detailed report on the Gray Vireo population in this area. We recommend a continuation of current vireo monitoring efforts within the Sevilleta NWR to gain a better understanding of the vireo population dynamics. Future management activities within the refuge will benefit from additional data regarding this threatened species.

Maia graduated in 2016 with a B.S. in Wildlife Ecology from University of Wisconsin, Madison. She went on to start a CSA farm in Wisconsin.

Matee Wolf

Maia’s and Matee’s 2015 REU project was “Gray Vireo (Vireo vicinior) nesting success and site selection in response to prescribed fire on the Sevilleta National Wildlife Refuge.”

Matee graduate in 2015 with his B.S. in Wildlife Ecology from Humboldt State University. He is currently an Field Technician and Outreach Coordinator at the Hawaii VINE Project.

Melissa Paduani

Melissa’s 2015 REU project was “Small mammal population size and diversity: a response to the reintroduction of the Gunnison’s prairie dog.”

The Gunnison’s Prairie Dog (Cynomys gunnisoni) is an herbivorous, burrowing rodent species that was extirpated from the Sevilleta National Wildlife Refuge, and is currently the subject of a long-term ecological reintroduction experiment. They are ecosystem engineers that play a vital role in creating heterogeneous plant community assemblages and landscape structures that result in diverse mosaics of habitat. The burrowing activity of these mammals alters the biotic factors of the ecosystem, providing viable land for other small rodent species to inhabit. To better understand the Gunnison’s Prairie Dog and its effects on grassland ecosystems, we will compare small mammal population sizes and diversity between control sites A and C, and prairie dog reintroduction sites at plots B and D. To do this, live trapping of animals was performed on both control and treatment plots. Shermann traps were placed in a grid format on the two control and two reintroduction sites over a four-week period. A comparison of data from previous seasons of trapping on these plots was also used to address the long-term effects of the reintroduction on small mammal populations. It is hypothesized that the sites with the reintroduced prairie dogs will have a higher diversity and abundance of small mammals compared to that of the control sites. The results will demonstrate the effect C. gunnisoni has on small mammal communities in grassland systems, and provide insight to aid wildlife and habitat management plans that aim to preserve, restore, and maintain the natural diversity of flora and fauna as they have historically occurred on the refuge.

Melissa graduate in 2016 with a B.S. in Environmental Science from the University of of Central Florida.

Michelle Gray

Michelle’s 2015 REU project was “Investigation of polyploidy and flavonoid composition in Sphaeralcea.”

Sphaeralcea [Malvaceae] is a genus of perennial forbs native to the southwestern North America. Sphaeralcea, commonly known as globemallows, are most often characterized by distinctive orange flowers. However, a few species have been noted to have pink flowers rather than the characteristic orange. Most notable of these variable species is Sphaeralcea polychroma, which has incredible variation in flower color. In an investigation into chromosome counts of a few Sphaeralcea species, J.C. LaDuke (1986) found that all individuals that were sampled with pink flowers were tetraploid, which could indicate a correlation in floral color variation and polyploidy. In order to further investigate this hypothesis we performed an investigation of genome size across the genus Sphaeralcea. In our sampling of 9 species from New Mexico and Colorado, we found that variation in ploidy levels is abundant within the genus, and includes diploids, tetraploids, and octoploids. The majority of samples analyzed were considered to be tetraploids. However, within the same species up to three different ploidy levels were determined. While LaDuke’s hypothesis that non-orange-flowered taxa are tetraploid held for our samples, the majority of tetraploid individuals we sampled had orange flowers, indicating that there is not a simple relationship between ploidy and color. In addition to genome size determination we also carried out TLC analysis to determine the flavonoid makeup of globemallow flowers of different color, as the biochemical makeup of Sphaeralcea flowers has yet to be described in the literature. The separation of pigments using TLC was unsuccessful however.

Michelle is currently an undergraduate student at the University of Maryland.

Salvador Bastien

Salvador’s 2015 REU project was “Effect of precipitation treatments on black grama demography.”

We examined size distribution, seed production, and viability of Bouteloua eriopoda under nine years of monsoon rainfall manipulation. This Long Term Ecological Research (LTER) experiment is designed to imitate monsoon patterns predicted by climate change models at Sevilleta National Wildlife Refuge. Demographic measurements were collected in June before the monsoon growing season began. Seed counts and germination viability testing on water agar will be conducted once B. eriopoda florets go to seed but before culms shatter. We found significantly higher mean tussock volume in small rainfall event treatment plots compared to ambient control plots and higher net volume in both watered treatments compared to ambient controls. These results indicate that increased precipitation has a greater positive effect on B. eriopoda survival when distributed more evenly across time. This finding sheds light on how the dynamics of semiarid ecosystems may respond to shifting precipitation pulses in the southwestern US.

Salvador graduated in 2016 with a B.A. in Biology from Colorado College.

Sophia Zaynor

Sophia’s 2015 REU project was “Genetic structure in invasive Russian olive on the Middle Rio Grande.”

Analyzing population genetic diversity in invasive plants yields insight into that species’ dispersal pasterns and adaptive potential in a region. This study examines gene flow in populations of invasive Russian Olive, Elaeagnus angustifolia, along the Middle Rio Grande in New Mexico. Our goal was to assess and compare the extent of gene flow caused by seed dispersal via water and gene flow caused by seed dispersal via animals. We used polymorphic microsatellite markers developed by Gaskin et al. (2013) to analyze leaf tissue samples collected from 9-17 trees from each of the 9 populations or sub populations sampled. We predict that populations downstream will show more genetic diversity than populations downstream than populations upstream due to the fact seeds travel from upstream to downstream, and that alleles will decrease with frequency downstream. We also predict dispersal caused by animals will be significant within distances less than 30 kilometers, and that water dispersal will extend over much farther distances but with much less consistency than animal dispersal. Initial analyses suggest that very little genetic structure exists in Russian Olives populating the middle Rio Grande region, but much more analysis needs to be performed in order to answer initial questions.

Sophia graduated in 2016 with a B.S. in Biology from Kent State University.