Nutrition or Detoxification: Why Bats Visit Mineral Licks of the Amazonian Rainforest

Many animals in the tropics of Africa, Asia and South America regularly visit so-called salt or mineral licks to consume clay or drink clay-saturated water. Whether this behavior is used to supplement diets with locally limited nutrients or to buffer the effects of toxic secondary plant compounds remains unclear. In the Amazonian rainforest, pregnant and lactating bats are frequently observed and captured at mineral licks. We measured the nitrogen isotope ratio in wing tissue of omnivorous short-tailed fruit bats, Carollia perspicillata, and in an obligate fruit-eating bat, Artibeus obscurus, captured at mineral licks and at control sites in the rainforest. Carollia perspicillata with a plant-dominated diet were more often captured at mineral licks than individuals with an insect-dominated diet, although insects were more mineral depleted than fruits. In contrast, nitrogen isotope ratios of A. obscurus did not differ between individuals captured at mineral lick versus control sites. We conclude that pregnant and lactating fruit-eating bats do not visit mineral licks principally for minerals, but instead to buffer the effects of secondary plant compounds that they ingest in large quantities during periods of high energy demand. These findings have potential implications for the role of mineral licks for mammals in general, including humans

Biogeochemical hotspots in Forested Landscapes: The Role of Vernal Pools in Denitrification and Organic Matter

Quantifying spatial and temporal heterogeneity in ecosystem processes presents a challenge for conserving ecosystem function across landscapes. In particular, many ecosystems contain small features that play larger roles in ecosystem processes than their size would indicate; thus, they may represent ‘‘hotspots’’ of activity relative to their surroundings. Biogeochemical hotspots are characterized as small features within a landscape that show comparatively high chemical reaction rates. In northeastern forests in North America, vernal pools are abundant, small features that typically fill in spring with snow melt and precipitation and dry by the end of summer. Ephemeral flooding alters soil moisture and the depth of the soil’s oxic/anoxic boundary, which may affect biogeochemical processes. We studied the effects of vernal pools on leaf-litter decomposition rates, soil enzyme activity, and denitrification in vernal pools to assess whether they function as biogeochemical hotspots. Our results indicate that seasonal inundation enhanced leaf-litter decomposition, denitrification, and enzyme activity in vernal pools relative to adjacent forest sites. Leaves in seasonally flooded areas decomposed faster than leaves in terra firme forest sites. Flooding also influenced the C, N, and P stoichiometry of decomposing leaf litter and explained the variance in microbial extracellular enzyme activity for phosphatase, β-D- glucosidase, and β-N-acetylglucosaminidase. Additionally, denitrification rates were enhanced by seasonal flooding across all of the study pools. Collectively, these data suggest that vernal pool eco- systems may function as hotspots of leaf-litter decomposition and denitrification and play a significant role in decomposition and nutrient dynamics relative to their size

Trophic Trait Evolution Explains Variation in Nutrient Excretion Stoichiometry among Panamanian Armored Catfishes (Loricariidae)

Variation in nutrient excretion rates and stoichiometric ratios (e.g., nitrogen to phosphorus) by consumers can have substantial effects on aquatic ecosystem function. While phylogenetic signals within an assemblage often explain variation in nutrient recycling rates and stoichiometry, the phylogenetically conserved traits that underlie this phenomenon remain unclear. In particular, variation in nutrient excretion stoichiometry across a phylogeny might be driven by phylogenetic patterns in either diet or body stoichiometry. We examined the relative importance of these traits in explaining variation in nutrient recycling rates and stoichiometry in a diverse family of Neotropical-armored catfishes, Loricariidae, in Panamanian streams. We found significant variation in nutrient mineralization traits among species and subfamilies, but variation in nutrient excretion stoichiometry among species was best explained by trophic position rather than body stoichiometry. The variation in trophic position among Panamanian species was consistent with variation in the trophic niche of their genera across South America, suggesting that phylogenetic patterns underpin the evolution of trophic and nutrient excretion traits among these species. Such geographical variation in nutrient mineralization patterns among closely related species may be common, given that trophic variation in fish lineages occurs widely. These results suggest that information on trophic trait evolution within lineages will advance our understanding of the functional contribution of animals to biogeochemical cycling

Promoting Diversity in Freshwater Science Through Mentoring: Celebrating Five Years of Instars

Instars is a mentoring program for undergraduate students from under-represented groups who are interested in the study of fresh waters. This year, the program will include an orientation workshop and will sponsor a special session entitled, “Our freshwater futures: an educational session particularly for undergraduates”. Instars began at the 2011 meeting in Providence, RI with 6 Fellows and 3 graduate mentors representing 7 states and 8 institutions. Participation has expanded and at the Joint Aquatic Sciences meeting in 2014 there were 16 Fellows and 8 mentors. Three of the mentors were alumni of the program. A broad diversity of under-represented groups, including African Americans, Hispanic/Latinos, Asian Americans, Native Americans, and First-Generation College students have participated in Instars, with at least 6 alumni continuing into SFS-related graduate programs. To date, funding has been provided by the Society for Freshwater Science for more than $50K with substantial assistance from partnering institutions. Institutions may help expand Instars by sponsoring undergraduates to attend the conference. We strongly encourage institutional sponsorship and are seeking resources to help provide stable funding for this growing program

The Instars Mentoring Program: Successes, Challenges, and Lessons Learned Over 5-Years of Broadening Participation in Freshwater Science

Mentoring Program engages undergraduate students from under-represented groups in the study of freshwaters and provides student funding to attend the SFS Annual Meeting. The program offers undergraduate Instars Fellows an opportunity to learn about the many disciplines of freshwater science and to interact with other undergraduates, graduate student mentors, and professional SFS members. Since the program’s inception in 2011, Instars has hosted a total of 63 undergraduates as Fellows and 32 SFS graduate students as Mentors. A broad diversity of under-represented groups, including African Americans, Hispanic/Latinos, Asian Americans, Native Americans, and First-Generation College students have participated, with many alumni continuing into SFS-related graduate programs and some even returning to the program as graduate mentors. Others have transitioned into careers in the freshwater sciences or education. Instars is an important program for the SFS’s Education and Diversity Committee to meet its mission to promote membership diversity. To date, funding has been provided by the SFS for more than $50K with substantial assistance from partnering institutions. In this presentation we outline the many successes of the program and remaining challenges

SFS Instars: A Mentoring Program to Increase Diversity in the Next Generation of Freshwater Scientists

Instars is a mentoring opportunity for undergraduates from under-represented groups interested in the study of freshwaters. The program provides opportunities for networking among graduates, faculty and professionals hoping to encourage diversity in our discipline. In addition to an orientation workshop, the 2013 program is sponsoring a special session, “The Future of Freshwater Science”. Instars was launched at the 2011 meeting in Providence, RI with 6 Fellows and 3 graduate mentors representing 7 states and 8 institutions. Participation expanded in 2012 with 11 Fellows and 8 mentors, representing 9 states and 15 institutions. A broad diversity of under-represented groups, including African Americans, Hispanic/Latinos, Asian Americans, Native Americans, and First-Generation College students have participated, with three alumni continuing into SFS-related graduate programs. To date, funding has been provided by the Society for Freshwater Science for more than $20K with substantial assistance from partnering institutions. Institutions may help expand Instars by sponsoring undergraduates to cover registration, travel or other costs associated with attending the conference. We strongly encourage institutional sponsorship and are seeking resources to help provide stable funding for this growing program

Salt lick clay contains higher concentrations of essential nutrients than insects or fruit.

<p>Content of iron, calcium, magnesium, sodium, and potassium (ppm dry mass+1 standard deviation) in clay collected from two mineral licks at the Tiputini Biodiversity Station compared to insects <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0002011#pone.0002011-Studier3" target="_blank">[23]</a> and fruit <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0002011#pone.0002011-Wendeln1" target="_blank">[30]</a> (note log scaling of y-axis). Minimum mineral requirements for growth and reproduction of small mammals are indicated by a solid horizontal line (data from National Research Council 1978 cited in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0002011#pone.0002011-Studier3" target="_blank">[23]</a>).</p

Undergraduate Mentoring at SFS and SWS: Increasing Diversity in the Next Generation of Aquatic Scientists

Both “Instars”, at SFS, and the SWS Undergraduate Mentoring Program encourage undergraduates from under-represented groups to pursue graduate school and careers in freshwater and wetland science. These programs aim to provide a professional network among participants, mentorship by established professionals and graduate students, exposure to disciplinary approaches in our science, and guidance in pursuing graduate education and careers in aquatic science. Coordinating committees achieve these goals by organizing workshops and special sessions during annual meetings, encouraging presentations made by participants in regular sessions at the meetings, and making available social media following the meetings. The NSF-sponsored SWS program began in 2004, has 8-11 undergraduates per year; similarly, the SFS Instars program, that was initiated in 2011, has approximately 10-12 undergraduate students and ~8 graduate mentors each year. Both programs are proud to have returning alumni serving as mentors. This poster will describe the increasing number of institutions with participants and faculty involvement, and will follow-up on the growing number of alumni who have graduated into freshwater-related graduate programs