TY - JOUR
T1 - Return to sender
T2 - the influence of larval behaviour on the distribution and settlement of the European oyster Ostrea edulis
AU - Rodriguez-Perez, Ana
AU - Sanderson, William G.
AU - Møller, Lene Friis
AU - Henry, Theodore B.
AU - James, Mark
N1 - The project was funded by the Nesbit Cleland Trust (St Abbs Marine Station), Royal Haskoning DHV, Scottish Natural Heritage and the MASTS pooling initiative (the Marine Alliance for Science and Technology for Scotland). MASTS is funded by the Scottish Funding Council (grant reference HR09011). The contribution of these funders is gratefully acknowledged. We are also grateful for additional support from the Dornoch Environmental Enhancement Project (DEEP: a partnership between Heriot‐Watt University, the Marine Conservation Society and the Glenmorangie Whisky Company: A15R10520).
PY - 2020/11/12
Y1 - 2020/11/12
N2 - Benthic marine invertebrates, such as oysters, rely on larval recruitment for their populations to persist. This can be by self-recruitment to the natal population or recruitment from geographically distant populations. Marine invertebrate larvae are increasingly understood to influence their dispersal through vertical migrations, based on a combination of responses to external cues and the larvae's ontogenetic stage. This study examined the larval behaviour of the European oyster Ostrea edulis in laboratory experiments. The aim was to establish if larvae show systematic behaviour that could affect dispersal. Vertical distribution, swimming speeds, and behaviour of O. edulis larvae were quantified throughout their ontogenetic development, and under scenarios of light/dark, food/no food, and two temperatures. Most O. edulis larvae concentrated at the bottom of the aquarium, independent of developmental stage or treatment, and consistently over time. Larvae behaved actively in ~50% of all bottom observations, indicating a behavioural function other than resting. At the surface, larvae frequently formed aggregations. In the water column, larvae swam with high vertical directionality and their distribution was homogenous. Swimming speeds ranged from 0.001 to 9.07 mm s-1. Advection close to the seabed is slower than in any other part of the water column. The demersal preference of O. edulis may be targeted towards increasing the likelihood of self-recruitment, which is consistent with the larvae's preference to settle in the presence of conspecifics. Stronger hydrodynamic environments are likely to override the larvae's demersal behaviour. It is recommended to restore European oyster beds at sufficient scale, density, and rugosity to promote retention of larvae within the natal population and minimize larval loss and mortality, as well as to account for the observed behaviours in networks of restoration sites.
AB - Benthic marine invertebrates, such as oysters, rely on larval recruitment for their populations to persist. This can be by self-recruitment to the natal population or recruitment from geographically distant populations. Marine invertebrate larvae are increasingly understood to influence their dispersal through vertical migrations, based on a combination of responses to external cues and the larvae's ontogenetic stage. This study examined the larval behaviour of the European oyster Ostrea edulis in laboratory experiments. The aim was to establish if larvae show systematic behaviour that could affect dispersal. Vertical distribution, swimming speeds, and behaviour of O. edulis larvae were quantified throughout their ontogenetic development, and under scenarios of light/dark, food/no food, and two temperatures. Most O. edulis larvae concentrated at the bottom of the aquarium, independent of developmental stage or treatment, and consistently over time. Larvae behaved actively in ~50% of all bottom observations, indicating a behavioural function other than resting. At the surface, larvae frequently formed aggregations. In the water column, larvae swam with high vertical directionality and their distribution was homogenous. Swimming speeds ranged from 0.001 to 9.07 mm s-1. Advection close to the seabed is slower than in any other part of the water column. The demersal preference of O. edulis may be targeted towards increasing the likelihood of self-recruitment, which is consistent with the larvae's preference to settle in the presence of conspecifics. Stronger hydrodynamic environments are likely to override the larvae's demersal behaviour. It is recommended to restore European oyster beds at sufficient scale, density, and rugosity to promote retention of larvae within the natal population and minimize larval loss and mortality, as well as to account for the observed behaviours in networks of restoration sites.
KW - Bivalves
KW - Conservation management
KW - Dispersal
KW - Estuary
KW - Invertebrates
KW - Restoration
KW - Self-recruitment
KW - Subtidal
KW - Swimming speeds
KW - Vertical distribution
U2 - 10.1002/aqc.3429
DO - 10.1002/aqc.3429
M3 - Article
SN - 1052-7613
VL - 30
SP - 2116
EP - 2132
JO - Aquatic Conservation: Marine and Freshwater Ecosystems
JF - Aquatic Conservation: Marine and Freshwater Ecosystems
IS - 11
ER -
