Induced nest failure as a mechanism for controlling invasive smallmouth (Micropterus dolomieu) and largemouth bass (Micropterus salmoides) (2017 PhD)

Smallmouth (Micropterus dolomieu) and largemouth bass (M. salmoides) are invasive species in many parts of the world. Invasive bass can change native communities through predation and competition. Control efforts for bass have been limited, and sometimes result in increased abundance due to overcompensation. I used a combination of field experiments and computer simulations to evaluate whether induced nest failure can control bass, and to determine the best methods for using induced nest failure. Stage-structured population simulations suggest that the amount of nest failure necessary to achieve control is likely to vary among populations (by up to 32% in my simulations), and that populations that are prone to overcompensation require more effort in general. Field experiments suggested that the removal of nest-guarding male bass increases the rate of nest failure from 42% to 94%, is most effective during the eggs stage, but did not detect a recruitment effect after 1 year (data from subsequent years may provide some insight). I also developed a stochastic, multi-generational, and density-dependent individual-based model that indicated that nest failure should occur annually, and may be useful as a part of an integrated pest management plan that exploits multiple approaches (e.g., nest failure and the removal of young bass). It is possible to achieve control within 15 years for many combinations of nest failure and removal, but there appear to be thresholds below which control may not be possible (e.g. ~60% nest failure in absence of supplemental removal). Future studies should identify whether there are environmental conditions that limit the effectiveness of nest failure (e.g., protracted spawning seasons, low rates of nest predation or sedimentation). This method is also relevant to the control or conservation of many species among the 41 families of bony fishes that employ nest guarding, including cichlids and gobies.

Loppnow GL, K Vascotto, PA Venturelli (2013) Invasive smallmouth bass (Micropterus dolomieu): History, impacts, and control. Management of Biological Invasions 4:191-206

Loppnow GL, PA Venturelli (2014) Stage-structured simulations suggest that removing young of the year is an effective method for controlling invasive smallmouth bass. Transactions of the American Fisheries Society 143:1341-1347

Honsey AE, GL Loppnow, TJ Martin, LA Schroeder, MM Tomamichel, NT Huempfner, PA Venturelli (2018) Reeling them in: initial insight into the factors affecting presentation attendance at American Fisheries Society meetings. Fisheries 43:98-105