0000000000406534
AUTHOR
Sara Hočevar
Marine food web perspective to fisheries‐induced evolution
Abstract Fisheries exploitation can cause genetic changes in heritable traits of targeted stocks. The direction of selective pressure forced by harvest acts typically in reverse to natural selection and selects for explicit life histories, usually for younger and smaller spawners with deprived spawning potential. While the consequences that such selection might have on the population dynamics of a single species are well emphasized, we are just beginning to perceive the variety and severity of its propagating effects within the entire marine food webs and ecosystems. Here, we highlight the potential pathways in which fisheries‐induced evolution, driven by size‐selective fishing, might reson…
Multiple‐batch spawning as a bet‐hedging strategy in highly stochastic environments: An exploratory analysis of Atlantic cod
Stochastic environments shape life‐history traits and can promote selection for risk‐spreading strategies, such as bet‐hedging. Although the strategy has often been hypothesised to exist for various species, empirical tests providing firm evidence have been rare, mainly due to the challenge in tracking fitness across generations. Here, we take a ‘proof of principle’ approach to explore whether the reproductive strategy of multiple‐batch spawning constitutes a bet‐hedging. We used Atlantic cod (Gadus morhua) as the study species and parameterised an eco‐evolutionary model, using empirical data on size‐related reproductive and survival traits. To evaluate the fitness benefits of multiple‐batc…
Multiple-batch spawning: a risk-spreading strategy disarmed by highly intensive size-selective fishing rate
Can the advantage of risk-managing life-history strategies become a disadvantage under human-induced evolution? Organisms have adapted to the variability and uncertainty of environmental conditions with a vast diversity of life-history strategies. One such evolved strategy is multiple-batch spawning, a spawning strategy common to long-lived fishes that ‘hedge their bets' by distributing the risk to their offspring on a temporal and spatial scale. The fitness benefits of this spawning strategy increase with female body size, the very trait that size-selective fishing targets. By applying an empirically and theoretically motivated eco-evolutionary mechanistic model that was parameterized for …
Marine food web perspective to fisheries-induced evolution
Fisheries exploitation can cause genetic changes in heritable traits of targeted stocks. The direction of selective pressure forced by harvest acts typically in reverse to natural selection and selects for explicit life-histories, usually for younger and smaller spawners with deprived spawning potential. While the consequences that such selection might have on the populational dynamics of a single species are well emphasised, we are just beginning to perceive the variety and severity of its propagating effects within the entire marine food webs and ecosystems. Here, we highlight the potential pathways in which fishing-induced evolution, driven by size-selective fishing, might resonate throu…
Pathways towards a sustainable future envisioned by early-career conservation researchers
Scientists have warned decision-makers about the severe consequences of the global environmental crisis since the 1970s. Yet ecological degradation continues and little has been done to address climate change. We investigated early-career conservation researchers' (ECR) perspectives on, and prioritization of, actions furthering sustainability. We conducted a survey (n = 67) and an interactive workshop (n = 35) for ECR attendees of the 5th European Congress of Conservation Biology (2018). Building on these data and discussions, we identified ongoing and forthcoming advances in conservation science. These include increased transdisciplinarity, science communication, advocacy in conservati…
In the light of life histories, bet-hedging, and fisheries-induced change : case Atlantic cod (Gadus morhua)
Luonto on täynnä monimutkaisia ilmiöitä, epälineaarisuutta ja enemmän tai vähemmän satunnaisia muutoksia. Nämä olosuhteet ylläpitävät vaihtelua lajien välillä ja lajien sisällä elinkierto-ominaisuuksissa sekä yksilöiden ekologisissa rooleissa. Tässä väitöskirjassa tutkin biologisen systeemin eri tasoilla evolutiivisia ja ekologisia hyötyjä, jotka liittyvät Atlantin turskalla (Gadus morhua) havaittuun vaihteluun elinkierto-ominaisuuksissa. Tutkin eko-evolutiivista dynamiikkaa hyödyntäen empiirisille systeemeille kehitettyjä mekanistisia malleja Atlantin turskalle sekä Skagerrakin ravintoverkolle. Kelpoisuuden analysointi osoitti, että turskan kudun jakaminen useisiin kutukertoihin on riskin …