Larval Transport and Dispersal in the Coastal Ocean and Consequences for Population Connectivity

Beyond connectivity: how empirical methods can quantify population persistence to improve marine protected‐area design

“…Note that the elements of some ''observed'' connectivity matrices reported in empirical papers are presented as absolute numbers of individuals , Saenz-Agudelo et al 2011), rather than probabilities or proportions. The ''realized'' connectivity matrix, which is required for determining persistence, contains total reproductive output in each patch, the movement of larvae between patches, and the subsequent survival to maturity within patches (Gerber et al 2005, Pineda et al 2007, Hamilton et al 2008, Burgess et al 2012. Empirical estimates of the realized connectivity matrix may also be a snapshot of the realized connectivity matrix C we described in the section above on Persistence in a network of connected populations.…”

“…3). When connectivity matrices are calculated via particle tracking in hydrodynamic models, the probabilities account for processes (physical and sometimes behavioral) influencing larval movement and successful settlement, but they may or may not include larval mortality or spatially variable egg production (Pineda et al 2007, Watson et al 2010. When connectivity matrices are quantified from field studies, as in the studies we reviewed, the probabilities necessarily include egg production, transport (physical and behavioral), larval mortality, and settlement, as well as typically including any early post-settlement mortality that occurred before sampling or counting by the researcher.…”

“…In essence, patterns of larval dispersal and population connectivity determine whether a particular reserve configuration produces a spatial distribution of survival and reproductive rates that are adequate for persistence. Larval dispersal patterns are also one of the largest sources of uncertainty in determining the effectiveness of MPAs, and are notoriously difficult to measure empirically due to the small size and high dispersal potential of larvae (Levin 2006, Pineda et al 2007, Cowen and Sponaugle 2009.…”

Movement patterns and rheoreaction of larvae of a fluvial specialist (nase, Chondrostoma nasus): the role of active versus passive components of behaviour in dispersal

“…It has been shown that fish can detect fine-scale stimuli induced by the current and actively react to them from early larval stages onwards (Garner 1999;Stoll and Beeck 2012). In marine fish ecology, the importance of larval behaviour for dispersal has been recognized during the past decade (Fiksen et al 2007;Gallego et al 2007;Leis 2007), and the need to break "the behavioural black box" has been realized (Pineda et al 2007). Moreover, basic behavioural features of fish larvae have already been successfully incorporated into elaborate 3D models of physical-biological interactions, which have increasingly become an integral tool for understanding larval fish dynamics in the sea (Gallego et al 2007), while in rivers these methods are in their infancy (Schludermann et al 2012;Lechner et al 2016).…”

“…Moreover, basic behavioural features of fish larvae have already been successfully incorporated into elaborate 3D models of physical-biological interactions, which have increasingly become an integral tool for understanding larval fish dynamics in the sea (Gallego et al 2007), while in rivers these methods are in their infancy (Schludermann et al 2012;Lechner et al 2016). It has been recognized that certain "longterm" behavioural changes may considerably contribute to larval dispersion -these factors involve environmental stimuli such as odours, sounds and light, time of day, water temperature, salinity, food availability, or ontogeny -and act on time scales of hours, days, and weeks (Pineda et al 2007). Minimal knowledge, however, exists on behavioural adaptation operating on scales of seconds to minutes, which responds to temporary "short-term" physical and biological triggers (Pineda et al 2007) or to factors that change rapidly in space (e.g., flow conditions, rheogradients) as fish larvae move.…”