Invasive control and native restoration: Directing ecosystem transformation through purposeful food web manipulations

Fisheries, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 22, 2025

ABSTRACT Ecosystems are abruptly changing due to invasive species and global climate change. In lakes, Rainbow Smelt Osmerus mordax can cause negative ecosystem effects through competitive predatory interactions with native leading food web shifts away from dominance, altered zooplankton communities, the decline or extirpation of cool coldwater fishes. We conducted two whole-lake removals simultaneous introductions Cisco Coregonus artedi stocking. About 327 1.6 adult Smelt/ha were removed about 45 Cisco/ha stocked over 4 years into experimental lakes. one system, Yellow Perch Perca flavscens relative abundance density significantly increased by 556% 143% post-manipulation, respectively. other Walleye Sander vitreus 26% became consistently present in pelagic zone post-manipulation (allowing for estimation). decreased >85% both The ecosystems shifted dominance while insignificant components webs. these intensive manipulations, we applied Resist–Accept–Direct (RAD) adaptation framework test an applicable ecological strategy used panarchy theory as ecologically grounded pathway purposefully direct transformation. this holistic management better understand manage undesired change—“food thinking.” context our study, directed towards structures, interactions, processes, which mitigated driven effects.

Language: Английский

The decline of walleye populations: an ecological tipping point?

FACETS, Journal Year: 2025, Volume and Issue: 10, P. 1 - 17

Published: Jan. 1, 2025

Walleye/ogaa ( Sander vitreus (Mitchill)) (hereafter, walleye; ogaa = Ojibwe translation) populations have historically supported important multi-use, harvest-oriented fisheries. Despite intensive management, walleye declined in the midwestern United States raising concerns about sustainability of species. Numerous factors been implicated population declines, including climate change, habitat loss, invasive species, species-interactions, production overharvest (i.e., harvest consistently exceeding annual production), and changing angler behaviors. These negatively influenced natural recruitment contributed to depensatory dynamics. I provide a review perspective suggesting that current trajectory is at or nearing an ecological tipping point. Although fish are often considered compensatory density-dependent), appear prone depensation positive density dependence). My suggest management for misaligned. A change towards resource focus using ecosystem-based fisheries recognition as social–ecological systems needed conservation. If ensues, persistence will likely be further threatened because many drivers outside managerial control, those commonly used within control seemingly ineffective sustaining rehabilitating naturally reproducing populations.

Language: Английский