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Proportional changes in stability (%) of marine metapopulation under climate change scenarios involving (a) abiotic change in ocean current alone, or the addition of (b) 40% increase of adult mortality and (c) 7-day reduction in PLD. (e) Metapopulation stability under the control scenario using present ocean currents biophysical model (1998-2007) and adult mortality at d = 0.5 is shown as a reference. The bars and error bars show the average and standard deviation among the different five spawning time respectively.
Source publication
Climate change is having multiple impacts on marine species characterized by sedentary adult and pelagic larval phases, from increasing adult mortality to changes in larval duration and ocean currents. Recent studies have shown impacts of climate change on species persistence through direct effects on individual survival and development, but few ha...
Contexts in source publication
Context 1
... and present (1998-2007) scenarios of ocean currents along the northeast Pacific coastal system predict that mean, variance and covariance of connectivity are expected to decrease (Δm a < 0, Δv a < 0, Δc a < 0) and realized connections to increase (Δr a > 0) (Fig. 4). Stability increased for the majority of PLDs, especially for longer PLDs (Fig. 5a), which can be explained by corresponding changes in components of connectivity (Fig. 4). The decreases of both mean and variance in our future ocean currents scenario produce a decrease and increase of stability respectively (Fig. 3). These opposite responses to individual components result in a weak predicted change in stability ...
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... changes in components of connectivity (Fig. 4). The decreases of both mean and variance in our future ocean currents scenario produce a decrease and increase of stability respectively (Fig. 3). These opposite responses to individual components result in a weak predicted change in stability resulting from changes in ocean transport alone (Fig. 5a). However, stability is more sensitive to variance than to mean connectivity (Fig. 3), and the effect of variance decreases still surpassed the decrease in mean connectivity and contributed a net increase of stability across PLD ...
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... strong effect of PLD on components of connectivity over short PLD values (Fig. 4), directly explain the effect of climate-induced increase in temperature on metapopulation stability (Fig. 5). Both 7-day (scenario PLD-7: Fig. 4) and 14-day (scenario PLD-14: Supporting information) reductions of larval duration resulted in an increase of mean (Δm b > 0) and variance (Δv b > 0) of connectivity and in a decrease of realized connections (Δr b < ...
Context 4
... short PLDs (1-50 days), the reduction of larval duration resulted in an increase of both mean and variance of connectivity (Fig. 4). For PLDs ≤ 8 days, the temperature driven increase in mean connectivity dominated over both the increase in variance and the decrease of covariance and resulted in an increase of stability in both scenarios PLD-7 ( Fig. 5) and PLD-14 (Supporting information). For PLDs ≥ 8 days, the increase in variance become dominant and resulted in a decrease of stability (Fig. ...
Context 5
... 8 days, the temperature driven increase in mean connectivity dominated over both the increase in variance and the decrease of covariance and resulted in an increase of stability in both scenarios PLD-7 ( Fig. 5) and PLD-14 (Supporting information). For PLDs ≥ 8 days, the increase in variance become dominant and resulted in a decrease of stability (Fig. ...
Citations
... Furthermore, to assess migration rates efficiently, it is recommended to collect the samples from the same year/season to minimise any potential biases due to temporal variability. In addition to monitoring the changes in mussel populations, investigating the effects of climate change on mussel connectivity is also crucial: Climate change is expected to disrupt larval dispersal through changes in temperature, salinity levels, and current patterns, potentially leading to declines in mussel populations and shifts in their distribution [55][56][57] . Understanding how these changes may impact mussel populations is important for developing effective management strategies to maintain their health and sustainability. ...
The mussel industry faces challenges such as low and inconsistent levels of larvae settlement and poor-quality spat, leading to variable production. However, mussel farming remains a vital sustainable and environmentally responsible method for producing protein, fostering ecological responsibility in the aquaculture sector. We investigate the population connectivity and larval dispersion of blue mussels (Mytilus edulis) in Scottish waters, as a case study, using a multidisciplinary approach that combined genetic data and particle modelling. This research allows us to develop a thorough understanding of blue mussel population dynamics in mid-latitude fjord regions, to infer gene-flow patterns, and to estimate population divergence. Our findings reveal a primary south-to-north particle transport direction and the presence of five genetic clusters. We discover a significant and continuous genetic material exchange among populations within the study area, with our biophysical model’s outcomes aligning with our genetic observations. Additionally, our model reveals a robust connection between the southwest coast and the rest of the west coast. This study will guide the preservation of mussel farming regions, ensuring sustainable populations that contribute to marine ecosystem health and resilience.
... From other modeling studies (Figueiredo et al., 2022), it is expected that the greatest effect of climate change on larval dispersal will likely be reduced connectivity and increased self-recruitment due to shorter larval periods in warmer waters, particularly for short PLD species. However, some changes in speed and direction of currents may also be expected, which are likely to more strongly impact long PLD species (Bani et al., 2021). Connections which have high variability between them might be under greater threat to disruption by climate change. ...
Introduction
Patterns of larval dispersal in the marine environment have many implications for population dynamics, biodiversity, fisheries, ecosystem function, and the effectiveness of marine protected areas. There is tremendous variation in factors that influence the direction and success of marine larval dispersal, making accurate prediction exceedingly difficult. The key physical factor is the pattern of water movement, while two key biological factors are the amount of time larvae spend drifting in the ocean (pelagic larval duration - PLD) and the time of the year at which adult populations release larvae. Here, we assess the role of these factors in the variation of predicted larval dispersal and settlement patterns from 15 locations around Aotearoa New Zealand.
Methods
The Moana Project Backbone circulation model paired with OpenDrift was used to simulate Lagrangian larval dispersal in the ocean with basic vertical control across four differing PLD groups (7, 14, 30, and 70 days) for each of twelve months.
Results
Considerable variation was observed in the pattern of particle dispersal for each major variable: release location, PLD group, and the month of release. As expected, dispersal distances increased with PLD length, but the size of this effect differed across both release location and month. Increased and directional particle dispersal matched some expectations from well-known currents, but surprisingly high self-recruitment levels were recorded in some locations.
Discussion
These predictions of larval dispersal provide, for the first time, an empirical overview of coastal larval dispersal around Aoteaora New Zealand’s main islands and highlight potential locations of “barriers” to dispersal. This dataset should prove valuable in helping predict larval connectivity across a broad range of species in this environment for diverse purposes.
... Biophysical modeling of larval dispersal is a key tool in marine conservation planning. 34,36,37 However, few models have considered the implications of climate change on multiple aspects of larval dynamics, 13,38 such as changes in dispersal distances and the availability of suitable habitats for settlement. These considerations are essential because larval dispersal across national borders may be critical for metapopulation persistence, so changes in connectivity imply changes in probability of persistence. ...
... However, local retention improves for most species, suggesting that establishing large marine reserves in areas that will become more isolated is critical to maintaining self-replenishment and supporting local populations (Table 1). 56 Like other studies, 13,38 we found that the strength of connections weakens, the overall larval recruitment decreases, and that some nodes for species with short PLD may become disconnected. Under a future climate scenario, networks of marine reserves will need to prioritize the protection of key stepping-stone nodes to avoid the fragmentation or collapse of larval dispersal processes in the region (Table 1). ...
... We simulated two contrasting scenarios to investigate the potential effect of climate change on larval connectivity due to reduction in PLD with increased temperatures and the reduction of recruitment habitat due to climate change, since both could significantly alter metapopulation dynamics. 13,38 In the first or ''present'' scenario, we downscaled the larval connectivity matrices to the polygon unit (following the approach described by Á lvarez-Romero et al. 13 ) based on two factors: probability of connections between two polygons according to the connectivity matrix based on the PLD reported for each focal taxon in the literature, and the total area with giant kelp found within each polygon. ...
Article Integrating climate adaptation and transboundary management: Guidelines for designing climate-smart marine protected areas Graphical abstract Highlights d We provide 21 guidelines for designing climate-smart transboundary protected areas d Future climates could decrease connectivity by 50% and hinder species recovery d Climate-smart networks require protecting critical sites and climate refugia d Adapting to climate change requires transboundary coordination in shared ecoregions
... A variety of physical and biological factors can affect the transport of marine larvae among locations (Paris et al., 2007;Cowen and Sponaugle, 2009;Bani et al., 2021). Larval dispersal is dependent on physical factors (diffusion and advection) and biotic factors (life-history traits, swimming capabilities and environmental tolerance) (Pineda et al., 2007), leading to a considerable impact of climate variability on population dynamics (Lacroix et al., 2017). ...
... However, very few studies considered climate change effects on mussel larval dispersal and connectivity (Szalaj et al., 2017;Bani et al., 2021). In addition, in shallow water bodies, episodes of extensive hypoxia will become more frequent and therefore necessary to investigate (Golosov et al., 2012). ...
... They found that an increase in PLD increased the connectivity distance and the number of connections, but decreased total settlement, local retention, and self-recruitment of larvae. Similarly, Bani et al., (2021) concluded that the stability of species with short PLD is more sensitive to the mean value of dispersal among few nearby habitats while species with long PLD are more sensitive J o u r n a l P r e -p r o o f to temporal variance of larval dispersal between many distant habitats. In this system, only drastic changes in PLD (reduction to 6 days or increase to 36 days) would affect the connectivity of the system. ...
Larval dispersal is dependent on multiple physical and biotic factors and is a key driver of population connectivity. Connectivity is believed to be important in determining how species will cope in a changing climate by allowing species’ ranges to expand or constrict in response to environmental shifts. In the following study, we couple a 3D physical model system with an individual-based model to answer whether climate change effects on mussel larvae will affect the dispersal and the structure of the demographic connectivity in the Limfjorden. The Limfjorden in Denmark supports a large mussel fishery of the species Mytilus edulis and extensive mussel farming, which may be impacted by changes in larval supply under climate change. We produced scenarios changing the pelagic larval duration, spawning time, and presence of spawning mussels after events of hypoxia, and analysed the changes in potential larval recruitment. The results showed that only the 6-day and 36-day pelagic larval duration scenarios are significantly different from the reference scenario. There was no significant event on changes in spawning time. We described the hydrography of the basins to explain the connectivity results and concluded that severe events of hypoxia could potentially lead to the isolation of the fjord. Overall, this well-connected system is very stable to the changes addressed in this study. It is important to continue the research in this area since the adaptation and evolution of species in a changing ocean will bring discoveries that will be useful for future management and conservation decisions.
... Temperature may play a significant role in shortening larval stages and dispersion distances in the tropics by increasing metabolic rates, as shown by lineage divergence in African prawns (Teske et al., 2008). However, high temperatures might also cause water stratification (Bashevkin et al., 2020) which, together with bathymetric salinity and oxygen concentration differences, the spreading of oxygen minimum zones, and the presence of strong currents (Bani et al., 2021) certainly may be barriers to larval dispersal influencing the bathymetric and horizontal distribution of certain taxa, and the fauna of the coast of Ghana is not an exception (Pabis et al., 2020;Sobczyk et al., 2021). ...
The Tropical East Atlantic is one of the least studied areas in the world's oceans, and thus a blank spot on the map of marine studies. Shaped by dynamic currents and shifting water masses, it is a key region in discussions about marine ecology, biodiversity, and zoogeography, while facing numerous, poorly understood, and unmonitored threats associated with climate change, acidification, and pollution. Polychaete diversity was assessed along four transects along the Ghana coast, from shallow to deep bottoms and distributed along the whole upwelling marine ecoregion. Despite high sampling effort, steep species accumulation curves demonstrated the necessity of further sampling in the region. We observed zonation of fauna by depth, and a decrease in species richness from 25 m to 1000 m depth. Polychaete communities were influenced by sediment type, presence of oxygen minimum zones, and local disturbances caused by elevated barium concentrations. Similar evenness along the depth gradient reflected the importance of rare species in the community structure. Differences in phylogenetic diversity, as reflected by taxonomic distinctness, were small, which suggested high ecosystem stability. The highly variable species richness at small scale (meters) showed the importance of ecological factors giving rise to microhabitat diversity, although we also noticed intermediate scale (50–300 km) differences affecting community structure. About 44 % of the species were rare (i.e. recorded only in three or fewer samples), highlighting the level of patchiness, while one fifth was distributed on all transects, therefore along the whole upwelling ecoregion, demonstrating the influence of the regional species pool on local communities at particular stations. Our study yielded 253 species, increasing the number of polychaetes known from this region by at least 50 %. This casts doubt on previous findings regarding Atlantic bioregionalization, biodiversity estimates and endemism, which appear to have been more pronouncedly affected by sampling bias than previously thought.
... Larvae were "released" from the benthos every day from Jun 1 to Jul 31 for the years 1998-2007 and 2068-2077 (future projection) and were tracked for 120 days. Although Daigle (2016) looked at connectivity between the 400 km 2 grid cells, individual larvae positions (latitude, longitude, depth) were recorded daily, allowing us to analyze connectivity patterns for a large range of PLDs (1-120 days) at multiple temporal/spatial resolutions (for more details see Bani et al. 2021). We used the outputs generated by Daigle (2016) to quantify connectivity in our study area. ...
... Rights reserved. use the biophysical model to run a post hoc spatially explicit metapopulation simulations on the resulting MPA network (Watson et al. 2011;Andrello et al. 2015a;Magris et al. 2018;Bani et al. 2021). This would quantify connectivity between priority areas to quantify how many larval particles are moving between sites to determine if the connectivity conserved is biologically meaningful (i.e., enough larvae are arriving at a site to sustain the population). ...
Marine Protected Areas (MPAs) are areas of marine ecosystems that have some level of protection to support one or more conservation objectives. One characteristic of MPA networks is that MPAs are spatially configured such that they provide the greatest protection possible for multiple species. Yet, it can be difficult to determine optimal MPA network arrangement due to insufficient information on multi-species habitat use and their dispersal abilities as larvae and adults. Here, we propose a modelling approach that involves determining the optimal MPA network configuration for multiple species assemblages, located at different depths and having differing dispersal abilities. As a case study, we applied this methodology in Pacific Canada where we identified optimal MPA configurations to protect 40 species having different pelagic larval duration (proxy for dispersal) at 3 different depth class groupings (proxy for habitat use). Taken together, we found dispersal ability had a larger impact on optimal MPA network configuration for species spending a long time as larvae compared to species spending a short time as larvae. We identify which 10% of this area is most important to conserve to maintain connectivity for a multi-species MPA network and show that half of these sites remain important to conserve in the future as climate change alters connectivity patterns. This model for MPA network design is feasible with limited data which is beneficial for application to other regions and ecosystems.
Climate-smart conservation addresses the vulnerability of biodiversity to climate change impacts but may require transboundary considerations. Here, we adapt and refine 16 biophysical guidelines for climate-smart marine reserves for the transboundary California Bight ecoregion. We link several climate-adaptation strategies (e.g., maintaining connectivity, representing climate refugia, and forecasting effectiveness of protection) by focusing on kelp forests and associated species. We quantify transboundary larval connectivity along ~800 km of coast and find that the number of connections and the average density of larvae dispersing through the network under future climate scenarios could decrease by ~50%, highlighting the need to protect critical steppingstone nodes. We also find that although focal species will generally recover with 30% protection, marine heatwaves could hinder subsequent recovery in the following 50 years, suggesting that protecting climate refugia and expanding the coverage of marine reserves is a priority. Together, these findings provide a first comprehensive framework for integrating climate resilience for networks of marine reserves and highlight the need for a coordinated approach in the California Bight ecoregion.
