We’re excited to collaborate with project leads Dr. Tom Wittum (OSU Vet Preventative Med) and Dr. Jiyoung Lee (OSU Environmental Health Sciences) on CDC-funded research investigating sources and fates of antibiotic-resistant bacteria in rivers.
In particular, our focus in on carbapenem drugs, which are often the antimicrobial therapy of choice to treat life-threatening invasive gram negative infections. The emergence of carbapenem-resistant Enterobacteriaceae (CRE) represents a critically important threat to public health. CRE are known to emerge in healthcare settings in response to frequent antimicrobial use and disseminate through environments that provide appropriate selection pressure. Our working hypothesis is that waste from metropolitan medical centers regularly transports CRE to wastewater treatment plants where they are maintained and ultimately discharged into surface waters, which may then serve as a reservoir for widespread dissemination of these highly resistant organisms. Study systems include the Scioto and Olentangy Rivers of central and southern Ohio.
The School of Environment & Natural Resources, Honors and Undergraduate Research Program has awarded Katherine Harris funding to support her undergraduate research project. Congrats Kate!
Kate, a member of the Stream and River Ecology (STRIVE) lab and undergraduate student majoring in Environmental Science, is studying stress responses of a common stream fish – Creek Chub (Semotilus atromachulatus; see photo below, by Brian Gratwicke) – to temperature variability of urban streams. Kate will be housing fish and running her experiment in aquatic habitat tanks (see below) in the STRIVE Wetlab at the Olentangy River Wetland Research Park.
There are thousands of dams throughout the rivers of the U.S., and they affect two essential aspects of the way rivers work: the natural flow of the river is disrupted, and the connection of upstream-to-downstream habitats are severed, impeding the movement of fish, macroinvertebrates and other aquatic organisms. However, the number of dams that are being decommissioned and removed is accelerating, and once the dam is gone, river channels and their floodplains are being restored to improve water quality, reconnect upstream and downstream habitats, and return the river to a more natural flow regime. Here in Columbus, the 75-year-old 5th Avenue dam on the Olentangy River (pictured above left) was removed in the fall of 2012, clearing the way for the river channel and floodplain to be restored (right next to Ohio Stadium on the OSU campus, see pictures below). We have been following several ecological responses of the river and its restoration after dam removal. One aspect of the river we tracked was the macroinvertebrate community, which is often used as an indicator of water quality.
Check out our new article about how macroinvertebrate communities responded after the 5th Avenue dam was removed:
2017) Seasonally distinct taxonomic and functional shifts in macroinvertebrate communities following dam removal. PeerJ 5:e3189 https://doi.org/10.7717/peerj.3189
Abstract: Dam removal is an increasingly popular restoration tool, but our understanding of ecological responses to dam removal over time is still in the early stages. We quantified seasonal benthic macroinvertebrate density, taxonomic composition, and functional traits for three years after lowhead dam removal in three reaches of the Olentangy River (Ohio, USA): two upstream of former dam (one restored, one unrestored), and one downstream of former dam. Macroinvertebrate community density, generic richness, and Shannon–Wiener diversity decreased between ∼9 and ∼15 months after dam removal; all three variables consistently increased thereafter. These threshold responses were dependent on reach location: density and richness increased ∼15 months after removal in upstream reaches versus ∼19 months downstream of the former dam. Initial macroinvertebrate density declines were likely related to seasonality or life-history characteristics, but density increased up to 2.27× from year to year in three out of four seasons (late autumn, early spring, summer) across all reaches. Macroinvertebrate community composition was similar among the three reaches, but differed seasonally based on non-metric multidimensional scaling (NMDS) and analysis of similarity (ANOSIM). Seasonal differences among communities tended to decrease after dam removal. We detected community-wide shifts in functional traits such as multivoltinism, depositional habitat use, burrowing, and collector-gatherer feeding mode. We observed that these traits were expressed most strongly with Chironomidae, which was the most abundant family. Our results suggest that seasonal environmental conditions can play a role in the response and recovery of macroinvertebrate communities—often used to monitor ecosystem condition—following dam removal. In particular, macroinvertebrate density and diversity can show recovery after dam removal, especially in seasons when macroinvertebrate density is typically lowest, with concomitant changes to functional trait abundance. Thus, we recommend scientists and managers consider responses to dam removal throughout the year. Further, similar density, generic richness, and functional traits among reaches suggest that channel restoration after dam removal may initially have equivocal effects on invertebrate communities.
Congrats to Bobby Davis, who recently defended and submitted his MSc thesis: Monitoring fish-community contaminant body burdens following lowhead dam removal in an urban river system. Bobby is now located in Washington, D.C., where he has started his new position with the World Wildlife Fund (WWF) in the aquaculture division of the food team, where he’ll be working on markets-based incentives programs to minimize the environmental impacts of aquaculture operations. Best of luck!
We’re thrilled to host Dr. Caryn Vaughn, Presidential Professor of Biology and George Lynn Cross Research Professor at the University of Oklahoma. Dr. Vaughn will be speaking this afternoon as part of our SENR Seminar Series. The title of her talk is: “Consumer Aggregations Act as Hotspots of Ecosystem Services in Rivers”. See announcement here: vaughn-flyer-2
Welcome Dr. Vaughn!
There was an American alligator sighted in the Olentangy River on campus yesterday (08/23) and again this morning (08/24). USDA has been notified and the alligator has now been captured (37″, 80 lbs) and will be sent to a sanctuary in South Carolina.
Photo credits: Kristen Diesburg and Anthony Ignozzi
Check out our new article:
Alberts, J.M., and S.M.P. Sullivan. 2016. Factors influencing aquatic-to-terrestrial contaminant transport to terrestrial arthropod consumers in a mid-size river system. Environmental Pollution 213: 53-62
- River contamination decreased with downstream longitudinal distance from a large urban center (see Figure below).
- Recipient consumer dynamics were influenced by riparian habitat complexity.
- Contaminant flux via emergent insects was not a strong predictor of terrestrial arthropod body burdens.
- Terrestrial consumer body burdens were best predicted by riparian land cover.
- Riparian land cover regulated aquatic-to-terrestrial contaminant transport.
Alayna successfully defended her MS thesis, “Short-term consequences of lowhead-dam removal for fish community dynamics in an urban river system” last Wed. May 4th and submitted her approved thesis this Tuesday. Alayna will be presenting some of her results at the upcoming Society for Freshwater Science meeting in Sacramento later this month. Nice job Alayna and best of luck in your next adventure!
Strive Lab recently participated in the 22nd annual Columbus City School Exceptional Science Fair. We showed off some cool aquatic insects from the Olentangy River, and taught students about animals many may have never seen before. Beechcroft High School students were able to pick through woody debris to find live insects, as well as look at some more interesting preserved specimens. We also showed some freshwater mussels from the Columbus Zoo and Aquarium Freshwater Mussel Conservation and Research Center.
Reina Tyl showing how to find live aquatic insects.
Clarissa Lawlis showing off a unionid mussel covered in zebra mussels.
Dr. David Manning gets students excited about aquatic insects!
New STRIVE findings published in Ecology show the importance of aquatic primary producers to terrestrial food webs. Of the primary producers, phytoplankton (19%) provided the greatest nutritional contribution to terrestrial consumers (including riparian beetles, spiders, damselflies, swallows, and raccoons), followed by periphyton (14%) and macrophytes (11%). Read below for more info:
Kautza, A., and S.M.P. Sullivan. 2016. The energetic contributions of aquatic primary producers to terrestrial food webs in a mid-size river system. Ecology. doi: 10.1890/15-1095
Abstract: Rivers are increasingly recognized as providing nutritional subsidies (i.e., energy and nutrients) to adjacent terrestrial food webs via depredation of aquatic organisms (e.g., emergent aquatic insects, crayfish, fish) by terrestrial consumers. However, because these prey organisms assimilate energy from both aquatic (e.g., benthic algae, phytoplankton, aquatic macrophytes) and terrestrial (e.g., riparian leaf detritus) primary producers, river subsidies to terrestrial consumers represent a combination of aquatically- and terrestrially-derived energy. To date, the explicit contribution of energy derived from aquatic primary producers to terrestrial consumers has not been fully explored yet might be expected to be quantitatively important to terrestrial food webs. At 12 reaches along a 185-km segment of the 6th-order Scioto River system (Ohio, USA), we quantified the relative contribution of energy derived from aquatic primary producers to a suite of terrestrial riparian consumers that integrate the adjacent landscape across multiple spatial scales through their foraging activities (tetragnathid spiders, rove beetles, adult coenagrionid damselflies, riparian swallows, and raccoons). We used naturally-abundant stable isotopes (13C and 15N) of periphyton, phytoplankton, macrophytes, and terrestrial vegetation to evaluate the energetic contribution of aquatic primary producers to terrestrial food webs. Shoreline tetragnathid spiders were most reliant on aquatic primary producers (50%), followed by wider-ranging raccoons (48%), damselflies (44%), and riparian swallows (41%). Of the primary producers, phytoplankton (19%) provisioned the greatest nutritional contribution to terrestrial consumers (considered collectively), followed by periphyton (14%) and macrophytes (11%). Our findings provide empirical evidence that aquatic primary producers of large streams and rivers can be a critical nutritional resource for terrestrial food webs. We also show that aquatically-derived nutrition contributes to both shoreline and broader-ranging terrestrial consumers and thus may be an important landscape-scale energetic linkage between rivers and upland habitats.