Marine larval dispersal is a complex biophysical process that depends on the effects of species biology and oceanography, leading to logistical difficulties in estimating connectivity among populations of marine animals with biphasic life cycles. To address this challenge, the application of multiple methodological approaches has been advocated, in order to increase confidence in estimates of population connectivity. However, studies seldom account for sources of uncertainty associated with each method, which undermines a direct comparative approach. In the present study we explicitly account for the statistical uncertainty in observed connectivity matrices derived from elemental chemistry of larval mussel shells, and compare these to predictions from a biophysical model of dispersal. To do this we manipulate the observed connectivity matrix by applying different confidence levels to the assignment of recruits to source populations, while concurrently modelling the intrinsic misclassification rate of larvae to known sources. We demonstrate that the correlation between the observed and modelled matrices increases as the number of observed recruits classified as unknowns approximates the observed larval misclassification rate. Using this approach, we show that unprecedented levels of concordance in connectivity estimates (r = 0.96) can be achieved, and at spatial scales (20–40 km) that are ecologically relevant.

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Innovative strategies are needed to escape the social‐ecological poverty that so frequently emerges from persistent overfishing of coral reef resources.This study focuses on fishing gear selectivity and its potential to increase ecosystem health and fisheries productivity without compromising the catch of profitable species.An investigation into the effects of an escape gap (3 cm × 30 cm) modification to the traditional African basket trap on total catch biomass, catch composition and monetary value in two locations with different historical levels of fishing was undertaken.Gated traps caught less low‐value fish (juveniles and narrow‐bodied coral reef species) while increasing the catch of high‐ and medium‐value fish (wider‐bodied commercially valuable species). The total monetary value of the gated trap catches was maintained in a heavily fished environment, while it increased in the less fisheries‐depleted area.For the most important local commercial species, the African white‐spotted rabbitfish (Siganus sutor), the gated traps significantly increased the mean length (by 12%) and weight (by 32%) of capture and decreased the proportion of catch under length at first maturity (Lmat) from 56% (traditional traps) to 25% (gated traps).Escape gaps have shown the potential to affect the structure of the fishery and ecosystem by enhancing the number of mature individuals, increasing reef biodiversity and promoting functionally diverse reef fish communities without compromising fisher's revenues. Copyright © 2013 John Wiley & Sons, Ltd.