Can energy depletion of wild Atlantic salmon kelts negotiating hydropower facilities lead to reduced survival?

0538806 - BC 2021 RIV CH eng J - Journal Article
Baktoft, H. - Gjelland, K.O. - Szabo-Meszaros, M. - Silva, A.T. - Říha, Milan - Okland, F. - Alfredsen, K. - Forseth, T.
Can energy depletion of wild Atlantic salmon kelts negotiating hydropower facilities lead to reduced survival?
Sustainability. Roč. 12, č. 18 (2020), s. 1-12, č. článku 7341. E-ISSN 2071-1050
Institutional support: RVO:60077344
Keywords : high-resolution 3D telemetry * 3D hydraulic modeling * anthropogenic structures * river connectivity * energetics model * energy expenditure
OECD category: Zoology
Impact factor: 3.251, year: 2020
Method of publishing: Open access
https://doi.org/10.3390/su12187341

Repeat spawners constitute an important component of Atlantic salmon populations, but survival of post-spawning individuals (kelts) are often compromised by anthropogenic structures such as hydropower plants (HPPs). Potential effects of HPPs include migration delays and associated increased energy depletion, which potentially results in increased overall mortality. We combined a detailed 3D hydraulic model with high-resolution 3D tracking of tagged kelts (length 73-104 cm) to obtain estimates of kelt movement through water. These estimates were then used in an energetics model to estimate hourly energy expenditure while negotiating the HPP area. Hourly kelt energy expenditure varied between 0.8 and 10.1 kJ x h(-1) and was dependent on kelt length. Degree of additional energy depletion can amount to several percent of remaining energy content (our study indicates 4-5 percentage points) potentially leading to reduced post-spawning survival. In turn, this can nullify the iteroparous breeding strategy and jeopardize long-term stability and persistence of Atlantic salmon populations inhabiting HPP rivers.
Permanent Link: http://hdl.handle.net/11104/0316526