Interactions between behaviour and physical forcing in the control of horizontal transport of decapod crustacean larvae. | Semantic Scholar (2024)

The presence of all larval stages showed that all species regulated depth sufficiently well to remain in the upper estuary, and regardless of swimming ability, larvae were retained in the estuary by occur- ring near the level of no net motion, even without completing tidal vertical migrations.

It is suggested that understanding larval dynamics could be crucial in managing N. norvegicus stocks on fishing grounds, in particular those with variable interannual oceanography and a low rate of larval donation from other grounds.

It is shown that interspecific differences in depth preference likely play a role in regulating differences in offshore migration from adult populations, and larvae of species that hatch in different locations and develop at different distances from the shore exhibit diverse larval swimming behaviors that regulate transport in dynamic upwelling regimes in previously undescribed ways.

It is shown that larval emigration from estuaries is favored even over minimizing visibility to predators, and phenotypic plasticity can conserve larval transport of both species when tidal and diel cycles are present.

The results of the simulations show that, for larvae of littoral species exhibiting DVM over a large expanse of the water column, upwelling may actually be a mechanism that enhances retention over the shelf.

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Results of this short-term study indicate that differential advection on a seasonal scale may be responsible for the temporal and spatial recruitment patterns of postlarvae observed in the Gulf of Carpentaria.

The ability of larvae to behaviourally regulate their position at scales of micrometres to metres when exposed to turbulent fluid motion in the water column, as evidenced in the benthic boundary layer, is unknown.

The focus of most research on vertical migration has shifted from the environmental control towards the search for ultimate reasons and the relative change of light intensity has been found to be the proximate cue that controls the upwards and downwards movements.

Die1 changes in the depth distribution of ChaoborwfIavicans larvae in thermally stratified aquaria with a distinct light gradient revealed that the larvae responded behaviorally to the presence of fish, and the fish effect persisted for more than 15 d but was reversible.

The lack of an endogenous circa-tidal vertical migration rhythm in larvae of the shore crab Carcinus maenas suggests that Swedish shore crabs are reproductively isolated from the British Isles populations, where this behaviour has been demonstrated to be inherited.

It is concluded that physical factors that result in a departure from unidirectional, depth-uniform water flow provide the opportunity for retention of larvae, and therefore of self-recruitment.

The lack of vertical migratory behavior and the presence of all larval stages of development suggest that Lophopanopeus spp.

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