Tag Archives: SwimPerArt

Neufeld, K.*, Watkinson, D., Tierney, K. and M.S. Poesch. (2018) Incorporating connectivity in measures of habitat suitability to assess impacts of hydrologic alteration to stream fish. Diversity and Distributions 24: 593-604.

Abstract

Hydrologic alterations are widespread in freshwater ecosystems worldwide and often detrimentally impact fish populations. Habitat suitability models are commonly used to assess these impacts, but these models frequently rely upon observed fish–habitat relationships rather than more mechanistic underpinnings. The aim of this study was to demonstrate how to incorporate swim performance into a measure of habitat connectivity at a fine scale, providing a method for assessing the availability of suitable habitat for stream fishes. We applied this technique to an endangered species, the Western Silvery Minnow Hybognathus argyritis, in the Milk River of southern Alberta, Canada. The Milk River is an augmented system, where a diversion in nearby St. Mary River augments flow by a factor >3 × (from 1–5 m3/s to 15–20 m3/s). We used laboratory measured swim performance of Western Silvery Minnow to develop a movement cost function that was used in conjunction with a habitat suitability model to assess habitat availability via a recently developed graph-theoretic metric, equivalent connected area (ECA). Stream augmentation altered not only habitat suitability but also habitat connectivity for this species. During augmentation, suitable habitat area declined by 81.3%. Changes in habitat connectivity were site dependent. Movement costs between habitat patches were lower during augmentation due to current-assisted dispersal and increased distance to patches during natural flows from dried streambeds. When movement costs were incorporated into ECA, ECA decreased by 78.0% during augmentation.With changing climate and increasing anthropogenic impacts on aquatic ecosystems, understanding how freshwater fishes relate to their habitat is critical for appropriate management. In many cases, such as the Western Silvery Minnow, mitigating habitat suitability may not be sufficient, as species are unable to reach suitable habitat. The incorporation of swim performance into habitat connectivity assessments, as carried out here, can be easily adapted to other species and situations and can improve the understanding of impacts to stream fishes and increase the effectiveness of mitigation efforts.

Citation: Neufeld, K.*, Watkinson, D., Tierney, K. and M.S. Poesch. (2018) Incorporating connectivity in measures of habitat suitability to assess impacts of hydrologic alteration to stream fish. Diversity and Distributions 24: 593-604.

Movement Cost of Western Silvery Minnow under Augment (top) and Natural (bottom) Flow Conditions

Also Read:

Theis, S.*  Castellanos D.A., Hamann A. and M.S. Poesch. (2023) Small-bodied fish species from western United States will be under severe water stress by 2040. Conservation Science and Practice: e12856.

*Lab members: Kenton Neufeld, Mark Poesch. Check out opportunities in the lab!

Veillard, M.F.*, Ruppert, J.L.W.*, Tierney, K., Watkinson, D., and M.S. Poesch. (2017) Comparative swimming and station-holding ability of the threatened Rocky Mountain Sculpin (Cottus sp.) from four hydrologically distinct rivers. Conservation Physiology 5: 1-12.

Abstract:

Hydrologic alterations, such as dams, culverts or diversions, can introduce new selection pressures on freshwater fishes, where they are required to adapt to novel environmental conditions. Our study investigated how species adapt to natural and altered stream flow, where we use the threatened Rocky Mountain Sculpin (Cottus sp.) as a model organism. We compared the swimming and station-holding performance of Rocky Mountain Sculpin from four different hydrologic regimes in Alberta and British Columbia, including the North Milk River, a system that experiences increased flows from a large-scale diversion. We measured the slip (Uslip) and failure (Uburst) velocities over three constant acceleration test trials. Uslipwas defined as the point at which individuals required the addition of bursting or swimming to maintain position. Uburst was defined as the point at which individuals were unable to hold position in the swimming chamber through swimming, bursting or holding techniques without fully or partially resting on the electrified back plate. We found individuals from the Flathead River in British Columbia (with the highest natural flow) failed at significantly higher Uburstvelocities than fish from the southern Albertan populations. However, there was no relationship between peak hydrologic flow from the natal river and Uburst or Uslip. Further, Uburst velocities decreased from 51.8 cm s−1 (7.2 BL s−1) to 45.6 cm s−1 (6.3 BL s−1) by the third consecutive test suggesting the use of anaerobic metabolism. Uslip was not different between trials suggesting the use of aerobic metabolism in station-holding behaviours (Uslip). Moreover, we found no significant differences in individuals from the altered North Milk River system. Finally, individual caudal morphological characteristics were related to both slip and failure velocities. Our study contributes to the conservation of Rocky Mountain Sculpin by providing the first documentation of swimming and station-holding abilities of this benthic fish.

Citation: Veillard, M.F.*, Ruppert, J.L.W.*, Tierney, K., Watkinson, D., and Poesch, M.S. 2017. Comparative swimming and station-holding ability of the threatened Rocky Mountain Sculpin (Cottus sp.) from four hydrologically distinct rivers. Conservation Physiology 5: 1-12.

Difference in Swim Performance Across Populations of Rocky Mountain Sculpin. Shown are Tukey contrasts (estimate +/- 95% confidence intervals) between rivers (top row) and constant acceleration trial (CAT) numbers (bottom row) for failure (Uburst) and slip (Uslip) velocities from linear effects model. Significant differences are noted in yellow; Rivers are abbreviated as: Flathead River (FH), St. Mary River (SM), Lee Creek (LC) and North Milk River (NM).

Also Read:

Rudolfsen, T.*, Watkinson, D. and Poesch, M.S. (2018) Morphological divergence of the Threatened Rocky Mountain sculpin (Cottus sp.) is driven by biogeography and flow regime. Aquatic Conservation: Marine and Freshwater Ecosystems 28: 78-86.

*Lab members: Marie Veillard, Jonathan Ruppert, Mark Poesch. Check out opportunities in the lab!