@article {5987, title = {Assessing linkages between small impoundments and long-term trajectories of prairie stream fish assemblages}, journal = {The American Midland Naturalist}, volume = {185}, year = {2021}, pages = {187 - 200}, keywords = {LTER-KNZ}, doi = {10.1674/0003-0031-185.2.187}, url = {https://bioone.org/journals/the-american-midland-naturalist/volume-185/issue-2/0003-0031-185.2.187/Assessing-Linkages-Between-Small-Impoundments-and-Long-term-Trajectories-of/10.1674/0003-0031-185.2.187.short}, author = {Hedden, Skyler C. and Lindsey A. Bruckerhoff and K. B. Gido} } @article {KNZ001993, title = {Biomass loss and change in species dominance shift stream community excretion stoichiometry during severe drought}, journal = {Freshwater Biology}, volume = {65}, year = {2020}, pages = {403-416}, abstract = {

\ \ \  1. Animals contribute significantly to nutrient cycling through excretion, but most studies consider their effects under relatively benign abiotic conditions. Disturbances such as drought may alter animals\’ nutrient contributions through shifts in species composition and biomass. Headwater streams are particularly vulnerable to extreme climate events and thus might show rapid changes in stream biota and their ecosystem effects.
\ \ \  2. We tested how biomass and subsequent ecosystem effects (nutrient cycling) of an intermittent prairie stream community changed during a drought. We quantified the biomass and contributions to nutrient cycling for assemblages comprising fishes, crayfish, and tadpoles in 12 isolated pools over 3 months encompassing the harshest drought on record for Kings Creek, KS, U.S.A. We predicted that macroconsumer biomass would decline with pool surface area and that differences in macroconsumer biomass and taxonomic composition would lead to different contributions of pool assemblages to nutrient cycling.
\ \ \  3. The biomass of pool assemblages declined with decreasing pool size, a pattern apparently driven by mortality, emigration, or metamorphosis. We also observed a change in assemblage structure of drying pools during drought relative to pool size, shifting dominance toward species with more drought-resistant traits. Accordingly, assemblage nitrogen (N) excretion rates declined as pool biomass was reduced, leading to a 58\% reduction in N available to epilithic biofilms. Phosphorus (P) excretion rates declined from June to July, but increased in August, as species with high P excretion rates maintained similar proportional biomass and biomass of a non-native fish increased. Molar N:P of pool assemblage excretion declined significantly throughout the drought and coincided with loss of southern redbelly dace (Chrosomus erythrogaster: Cyprinidae).
\ \ \  4. Animal-mediated nutrient cycling was altered by the loss of biomass and stoichiometric traits of taxa that differed in their occurrences and ability to tolerate abiotic conditions during drought. Elevated availability of dissolved N in isolated pools may increase N uptake rates by biofilms during drought conditions, indicating the importance of N excreted by aggregated macroconsumers, especially those with unique stoichiometric traits. While the significance of shifts in the composition of freshwater communities to ecosystems is not entirely known, additional losses in ecosystem function and changes in community structure may follow episodes of severe drought.

}, keywords = {LTER-KNZ}, doi = {10.1111/fwb.13433}, url = {https://onlinelibrary.wiley.com/doi/pdf/10.1111/fwb.13433}, author = {Hopper, Garrett W. and K. B. Gido and Pennock, Casey A. and Hedden, Skyler C. and Guinnip, James P. and Fisher, Molly A. and Tobler, Courtney M. and Hedden, Crosby K. and Lindsey A. Bruckerhoff} } @article {KNZ002012, title = {Dispersal drives changes in fish community abundance in intermittent stream networks}, journal = {River Research and Applications}, volume = {36}, year = {2020}, pages = {797-806}, abstract = {

Increasing trends in fragmentation and dewatering of streams warrants research on how populations and communities respond to varying water levels and barriers to movement. Although these responses are complicated by many spatial and temporal processes, long-term datasets might help reveal complex patterns and processes driving variability in species abundances. The objective of this study was to develop a predictive framework for fish community and population responses to varying levels of water availability across six sites in two intermittent stream networks sampled \>10\ years. We predicted that fishes would emigrate into intermittent reaches during wet conditions; thus, overall abundances within perennial source locations will decline. Accordingly, when intermittent reaches dry, fishes will contract to wetted habitats resulting in high abundance. Observed fish community abundances were highly variable within and among study sites, but four of six sites matched our predictions. A tagging study confirmed these results and demonstrated a substantial proportion of individuals moved away from perennial reaches and into newly wetted intermittent reaches. However, site and species-specific relationships were variable and likely depended on the habitat, metacommunity dynamics, and life history strategies. Findings suggest that species dispersal dynamics, in addition to recruitment and mortality, should be carefully considered when interpreting species responses to varying water levels, particularly in intermittent stream networks where access to habitat can change drastically with water availability.

}, keywords = {LTER-KNZ}, doi = {10.1002/rra.3599}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/rra.3599}, author = {Hedden, Skyler C. and K. B. Gido} } @article {KNZ002003, title = {Nowhere to swim: interspecific responses of prairie stream fishes in isolated pools during severe drought}, journal = {Aquatic Sciences}, volume = {82}, year = {2020}, abstract = {

Extreme drying can dramatically shift abiotic characteristics of streams and species respond differently as conditions change. We modified a conceptual model describing responses of aquatic invertebrate assemblages to stream drying to facilitate predictions of fish assemblage shifts in which thresholds of physiochemical gradients lead to punctuated losses of fish diversity as stream connectivity diminishes. We tested the applicability of this model during a record-breaking drought that reduced a perennial reach of a headwater prairie stream to a series of 12 isolated pools with variable levels of hyporheic connectivity that was associated with pool volume. We tracked fish assemblage structure in pools over seven weeks and measured abiotic conditions. Inter-specific differences in drought resistance traits were tested in the lab (i.e., thermal and hypoxia tolerance) for common species experiencing drought conditions. Species richness declined rapidly with pool volume associated with hyporheic connectivity. Abundance of the most common species prior to drought, Chrosomus erythrogaster (southern redbelly dace) declined 95\% and was extirpated from five pools during drought due to its low thermal tolerance. Despite being the least tolerant to hypoxia, Campostoma anomalum (central stoneroller) populations persisted in most pools. The remaining pools became dominated by a non-native extremophile fish, Gambusia affinis (western mosquitofish) and abundances of less resistant native species declined. Our study demonstrates that richness in drying pools is driven by factors associated with pool volume, and assemblage composition shifts from dominance by native species adapted to variable hydrological conditions to non-native species able to resist increasing temperatures and hypoxia. Sudden species loss associated with reduced stream connectivity can shift abundance patterns of prairie stream fish communities with potentially lagged effects on population and community dynamics.

}, keywords = {LTER-KNZ}, issn = {1015-1621}, doi = {10.1007/s00027-020-0716-2}, url = {http://link.springer.com/10.1007/s00027-020-0716-2}, author = {Hopper, Garrett W. and K. B. Gido and Pennock, Casey A. and Hedden, Skyler C. and Frenette, Bryan D. and Barts, Nick and Hedden, Crosby K. and Lindsey A. Bruckerhoff} } @article {KNZ001862, title = {Fine-scale movement and habitat use of a prairie stream fish assemblage}, journal = {Oecologia}, volume = {186}, year = {2018}, pages = {831{\textendash}842}, abstract = {

Measuring an organism\&$\#$39;s movement and habitat use is highly dependent on the spatial and temporal scale of the study, with most studies measuring distributions once a day or at less frequent intervals. Yet, to fully understand the rates of intra- and interspecific encounters among individuals, observations at finer spatial and temporal scales might be necessary. We used passive integrated transponder tags and antenna arrays to continuously monitor habitat use and vagility of three stream minnows; southern redbelly dace Chrosomus erythrogaster, central stoneroller Campostoma anomalum, and creek chub Semotilus atromaculatus, among and within pools of an intermittent stream. Most fish remained in the pool where they were caught and released, or returned after emigrating from the pool. Despite largely remaining within the release pool, distribution among four microhabitats differed significantly over six, 4-h time periods for all three species. Vagility, the summed distance moved among antennas, differed significantly among species. Individual vagility (m day-1) increased significantly with body length for stoneroller and chub, but not dace. Some individuals moved as much as 110 m day-1 within the pool, showcasing extensive movement at fine scales. Finally, we found no evidence that feeding activity changed as a result of differential habitat use over a 24-h period. Our findings indicate considerable variation in habitat use and movement occurs among species over a 24-h period. This suggests ecologists can broaden the interpretation of processes influencing community structure (e.g., resource partitioning, avoidance of predators) by quantifying species distributions across a range of spatial and temporal scales.

}, keywords = {LTER-KNZ}, doi = {10.1007/s00442-018-4073-y}, url = {https://link.springer.com/article/10.1007\%2Fs00442-018-4073-y}, author = {Pennock, C.A. and Nathan Cathcart, C. and Hedden, Skyler C. and Weber, Robert E. and K. B. Gido} }