Recipient Organization
STATE UNIV OF NEW YORK
(N/A)
SYRACUSE,NY 13210
Performing Department
Environmental & Forest Biology
Non Technical Summary
Climate change and non-native species are major concerns for the Great Lakes. Climate change in the region is expected to cause shifts in water chemistry and physical parameters, such as dissolved oxygen and water temperature. Non-native species have considerably altered the community composition within the Great Lakes, particularly benthic communities. As a result of non-native bent hic invaders, naturally occurring physical and biological patterns have been modified. The interaction between climate change and non-native species then becomes an important consideration for the management of the Great Lakes. I propose to examine how climate change may farther alter the benthos, causing a shift from Dreissena spp. dominance to dominance by a non-native freshwater oligochaete, Branchiura sowerbyi. Using a combination of water temperature, water chemistry, weather data and benthic sampling, will examine how shifts in local conditions contribute to benthic community composition. Furthermore, field and laboratory experiments will be conducted that examine how an increase in Bra11chiurn sowerbyi dominance with a changing climate may affect sediment nutrient release and the survival of a native species with conservation value, the burrowing mayfly (Hexogenia spp.). This research will be conducted primarily at the Old Woman Creek NERR in Huron, Ohio. Additional sampling will be conducted in Sandusky Bay and Maumee Bay in the western basin of Lake Erie. The proposed research will (1) provide baseline data for the Old Woma n Creek NERR regarding Branchiura sowerbyi , Dreissena and Hexagenia distribution and abundance within the Reserve, as well as adding to current distribution and abundance data available for the western basin of Lake Erie, (2) demonstrate how an increase in the non-native Branchiura sowerbyi may affect nutrient cycling and survival among native benthic invertebrates, and (3) contribute to key management implications for t he Great Lakes by highlighting links between climate change and non-native species.
Animal Health Component
(N/A)
Research Effort Categories
Basic
100%
Applied
(N/A)
Developmental
(N/A)
Goals / Objectives
The proposed research will (1) provide baseline data for the Old Woman Creek NERRregarding Branchiura sowerbyi, Dreissena and Hexagenia distribution and abundance within theReserve, as well as adding to current distribution and abundance data available for the westernbasin of Lake Erie, (2) demonstrate how an increase in the non-native Branchiura sowerbyi mayaffect nutrient cycling and survival among native benthic invertebrates, and (3) contribute to keymanagement implications for the Grent Lakes by highlighting links between climate change andnon-native species.
Project Methods
Baseline physical and water chemistry data will be collected monthly at three permanent locations at each of the sites (Old Woman Creek, Sandusky Bay and Maumee Bay), over a three year period. This will include data collection of: ( I ) water depth, (2) turbidity, (3) pH, (4) water temperature, (5) chlorophyll a, and (6) nitrogen and phosphorus concentrations of the water near the sediments and at the surface. Weather data will be continuously monitored from existing weather stations and from the NOAA National Data Buoy Center, including data from buoys at Old Woman Creek NERR (stations OWX01 and OWQ01) and additional stations in the western basin (THRO I , THLO I , SBIO l , MRHO l, HHLO l, and 45005).Sediment samples will be collected monthly from March through October using a petite ponar grab. Densities of Branchiura sowerbyi and Dreissena spp. will be determined. The number of sampling locations at each site will be determined following a preliminary survey and power analyses to capture t he complete variation of environmental variables present (nearshore and open water, different substrate types). Sampling locations will be selected based on known B. sowerbyi distributions. Abundance of B. sowerbyi and Dreissena sp. will be compared with water chemistry and weather data, using multiple analysis of covariance (MANCOVA), to observe how B. sowerbyi and Dreisse11a populations respond to local water and climatic conditions and to confirm or refute the hypotheses that B. sowerbyi should increase and Dreissena sp. decrease under warmer, hypoxic conditions.Objective 1. To determine how Branchiura sowerbyi affects the release of sediment nutrients (N and P), sediment cores will be collected a t sites with high and low abundances of the oligochaete, and analyzed for differences in nutrient concentrations. Nutrient levels of the water at the sediment-·water interface at high and low density sites ·will be collected and analyzed to determine if increased densities of B. sowerbyi are correlated with a direct increase of nutrients in the water column. Field data will be supported by laboratory experiments, which will be conducted at the Old Woman Creek Reserve and the Center for Integrated Research and Teaching of Aquatic Sciences (CIRTAS) located on the SUNY-ESF campus. For laboratory experiments, cores collected from the field with known densities (none, low and high) of B. sowerbyi will be placed in temperature controlled incubators that mimic various climate change scenarios (varied water temperature and oxygen levels in a factorial experiment). Nitrogen and phosphorus concentrations, from within the sediments and water column, will be quantified and compared to densities of B. sowerbyi. Additional treatments will include Dreisseno spp. and native oligochaetes (Limnodrilus spp.) at various densities to determine how potential changes in the benthic community composition relate to nutrient release under different climate regimes.Objective 2. Abundances of Hexagenio from sediment samples will be quantified and correlated with Branchiura sowerbyi abundances in situ from locations ·within Old Woman Creek, Sandusky Bay and Maumee Bay. Laboratory experiments wlli be conducted to explore the potential competitive relationship between these species. Incubators set at various ambient temperatures mimicking various climate change scenarios will have tanks containing different densities of both H sowerbyi and Hexagenia. Survivorship p and growth of Hexagenia will be quantified at 1week intervals for one month. Experiments will be conducted with different life stages (egg, early and late instar nymphs) of Hexagenia to observe if B. sowerbyi affects a specific stage in the life cycle of Hexagenia under different temperatures and conditions. Hexagenio eggs will be obtained from Jan Ciborowski (originally isolated from Lake Erie or Lake St. Clair) at the University of Winclsor, Canada, and grown at 4°C in dechlorinated water for use in later life stages (Smith et al. 2008).