ABSTRACT. Lagoons are highly productive coastal features that provide a range of natural services that society values. Their setting within the coastal landscape leaves them especially vulnerable to profound physical, ecological, and associated societal disturbance from global climate change. Expected shifts in physical and ecological characteristics range from changes in flushing regime, freshwater inputs, and water chemistry to complete inundation and loss and the concomitant loss of natural and human communities. Therefore, managing coastal lagoons in the context of global climate change is critical. Although management approaches will vary depending on local conditions and cultural norms, all management scenarios will need to be nimble and to make full use of the spectrum of values through which society views these unique ecosystems. We propose that this spectrum includes pragmatic, scholarly, aesthetic, and tacit categories of value. Pragmatic values such as fishery or tourism revenue are most easily quantified and are therefore more likely to be considered in management strategies. In contrast, tacit values such as a sense of place are more difficult to quantify and therefore more likely to be left out of explicit management justifications. However, tacit values are the most influential to stakeholder involvement because they both derive from and shape individual experiences and beliefs. Tacit values underpin all categories of social values that we describe and can be expected to have a strong influence over human behavior. The articulation and inclusion of the full spectrum of values, especially tacit values, will facilitate and support nimble adaptive management of coastal lagoon ecosystems in the context of global climate change.

Coupled biological and physical oceanographic models are powerful tools for studying connectivity among marine populations because they simulate the movement of larvae based on ocean currents and larval characteristics. However, while the models themselves have been parameterized and verified with physical empirical data, the simulated patterns of connectivity have rarely been compared to field observations. We demonstrate a framework for testing biological-physical oceanographic models by using them to generate simulated spatial genetic patterns through a simple population genetic model, and then testing these predictions with empirical genetic data. Both agreement and mismatches between predicted and observed genetic patterns can provide insights into mechanisms influencing larval connectivity in the coastal ocean. We use a high-resolution ROMS-CoSINE biological-physical model for Monterey Bay, California specifically modified to simulate dispersal of the acorn barnacle, Balanus glandula. Predicted spatial genetic patterns generated from both seasonal and annual connectivity matrices did not match an observed genetic cline in this species at either a mitochondrial or nuclear gene. However, information from this mismatch generated hypotheses testable with our modelling framework that including natural selection, larval input from a southern direction and/or increased nearshore larval retention might provide a better fit between predicted and observed patterns. Indeed, moderate selection and a range of combined larval retention and southern input values dramatically improve the fit between simulated and observed spatial genetic patterns. Our results suggest that integrating population genetic models with coupled biological-physical oceanographic models can provide new insights and a new means of verifying model predictions.

To investigate the biological and physical mechanisms affecting larval dispersal, we embedded a model of Balanus glandula larval development and behavior into physical circulation fields of waters along the central California coast. Physical circulation fields were generated by a three-dimensional ocean circulation model with a horizontal resolution of 1.5 km and 20 topography-following layers in the vertical. The ocean circulation model was forced by air-sea fluxes derived from a mesoscale atmospheric model and assimilated temperature and salinity data from the Autonomous Ocean Sampling Network II experiment. An ecosystem model that calculated chlorophyll a (a proxy for larval food concentration) was also coupled to the ocean circulation model. The coupled model of larval development, larval behavior, food concentration, and physical circulation was used to run simulations of larval dispersal. Simulation results predicted a greater return of larvae to the nearshore waters with relaxation circulation patterns than with upwelling. More larvae were supplied to the coast north of Monterey Bay than to the south, and larvae that successfully returned to the nearshore waters generally had limited dispersal distances. These modeling results agree with previous observations of B. glandula population dynamics in central California.Many intertidal marine species have a planktonic larval phase, and populations in the intertidal zone are largely shaped by the supply of these larvae. An understanding of the pathways of larval dispersal would provide many of the answers to questions about how intertidal populations are connected. However, direct observations of larvae dispersing in coastal waters are very sparse, because of the difficulty of making these observations. An alternative to direct observation is to predict the paths of dispersing larvae with model simulations. In this study, we model the dispersal of Balanus glandula larvae and predict dispersal pathways in coastal waters of central California.To model larval dispersal it is first necessary to understand the biology of the larvae. B. glandula is

Hydrographic surveys and moored observations in Rhode Island Sound (RIS) in water depths of 30-50 m, off the southern New England coast, revealed a near-bottom intrusion of anomalously warm and saline water in late fall 2009. The properties of this water mass, with peak salinity of nearly 35, are typical of slope water that is normally found offshore of the shelfbreak front, located approximately 100 km to the south. The slope water intrusion, with a horizontal spatial scale of about 45 km, appears to have been brought onto the outer shelf during the interaction of a Gulf Stream warm core ring with the shelfbreak east (upshelf) of RIS. The along-shelf transport rate of the intrusion can be explained as due to advection by the mean outer-shelf along-isobath current, although the transit time of the intrusion is also consistent with the self-advection of a dense bolus on a sloping shelf. The mechanism responsible for the large onshore movement of the intrusion from the outer shelf is not entirely clear, although a wind-driven upwelling circulation appeared to be responsible for its final movement into the RIS region. Depth-averaged salinity at all RIS mooring sites increased by 0.5-1 over the 3-4 week intrusion period suggesting that the intrusion mixed irreversibly, at least partially, with the ambient shelf water. The mixing of the salty intrusion over the shelf indicates that net cross-isobath fluxes of salt and other water properties have occurred.

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