Metapopulations are often distributed across habitat patches with distinct differences in nutritional resources. We investigate individual variability in diet among subpopulations of blue cod Parapercis colias across productivity gradients within Fiordland, New Zealand. δ 13 C and δ 15 N of basal organic matter, including phytoplankton, macroalgae, terrestrial detritus and the chemosymbiont-harbouring clam Solemya parkinsonii, were collected. P. colias from inner and outer fjord sites within 5 fjords were analysed for proportion of diet comprising S. parkinsonii, and δ 13 C and δ 15 N of muscle tissue. Relative abundance of photoautotrophic organic matter was quantified from surveys of chl a and abundance of common kelp Ecklonia radiata. Information on mussel beds was collected to characterise potential for benthic-pelagic coupling. A mass balance model using δ 13 C and δ 15N was used to estimate trophic level and proportion of organic matter from chemosynthesis for individual blue cod. Blue cod from the inner fjords had more variable use of organic matter originating from photoautotrophic versus chemoautotrophic sources than those from outer fjord regions. This was consistent with greater occurrence of S. parkinsonii in stomachs of blue cod from the inner fjords. Abundance of phytoplankton and occurrence of mussels statistically explained 87% of the variability in proportion of organic matter originating from chemosynthesis. These data provide an important example of variation in basal organic matter sources among subpopulations within a marine metapopulation. Our results demonstrate the importance of organic matter produced from chemosynthesis in coastal food webs providing a mechanism for maintenance of high trophic level consumers in marginal habitats. KEY WORDS: Chemoautotrophy · Food web · Fjord · Reef fish · Stable isotopes · Trophic level · MetapopulationResale or republication not permitted without written consent of the publisher Mar Ecol Prog Ser 466: 205-214, 2012 subpopulations, as indicated by diversity of basal organic matter sources, changes across environmental gradients.Metapopulation dynamics of many coastal invertebrates and fishes may be strongly influenced by habitat quality and the effects of the nutritional environment on local growth and reproductive output (e.g. Sanford & Menge 2007, Jack & Wing 2010. Though subpopulations can be linked by larval dispersal over relatively large distances, site fidelity by adult reef fish may result in large differences in diet, growth and egg production among habitats (Gust et al. 2002, Lawton et al. 2010. Accordingly, at this local population level, the food webs supporting generalist reef fish may reflect the relative availability of basal organic matter sources (Vander Zanden & Vadeboncoeur 2002, McLeod et al. 2010a. As resources become rare, or habitat quality changes, variability in diet among individuals may increase (Fry et al. 1999, Vander Zanden et al. 2010. In this case, specialisation or diversification in resource use at the ind...

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We exploit the pronounced and persistent low salinity layer in Doubtful Sound, southwest New Zealand, as a natural experimental system with sharp environmental gradients in which to study physical versus biological control of element incorporation into biogenic carbonate. Mussels Mytilus galloprovincialis transplanted to cages in the low salinity layer and saline layer in inner, mid and outer fjord habitats were used as biological integrators of physico-chemical conditions in each water mass over a period of several months. We used solution inductively coupled plasma mass spectrometry (ICP-MS) to measure the concentrations of 15 elements (Li, B, Mg, P, S, Mn, Fe, Co, Cu, Zn, Rb, Sr, Cd, Ba, Pb) in the experimental shell growth and relate spatial trends to those in salinity and elemental sources. S concentrations were consistently below detection limits while Zn and Rb showed no spatial variability. The majority of elements were subject to environmental control, likely reflecting ambient concentrations and salinity. Sr incorporation showed evidence of strong biological mediation of environmental signals via the crystal shell growth rate. These findings are a valuable addition to the growing body of literature seeking to resolve physical versus biological controls of individual trace element incorporation into biogenic carbonates, and have important consequences for their use as environmental indicators or tracers for ecological studies. KEY WORDS: Trace elements · ICP-MS · Mussels · FjordResale or republication not permitted without written consent of the publisher

The Shoreline Clean-up Assessment Technique (SCAT) is a well-tested tool that enables the systematic surveying of shorelines affected by oil spills. Using standardised terminology to document the nature and degree of shoreline oiling, SCAT was designed to support decision-making for shoreline clean-up operations. Formally integrated into the US response structure, this method is increasingly being adopted as a standard response procedure around the world. Over the years, SCAT has evolved to meet changing expectations of shoreline response into a tool that can formally guide and document decisions from the initial emergency phase of a response through to the termination of activities-which in large, complex cases could be many months or even years after the incident. The framework of developing a shoreline response programme at the beginning of an incident, implemented by SCAT teams providing shoreline treatment recommendations in support of operations throughout the duration of shoreline response was used extensively in DEEPWATER HORIZON. A properly designed SCAT programme able to gather the necessary relevant shoreline oiling data quickly and accurately for use in addressing immediate response needs can greatly reduce delays in action and the footprint of the response itself. SCAT's core principle of guiding operations can be overlooked in instances with inexperienced personnel or inappropriate competing objectives, resulting inconsiderable effort expended on SCAT surveys with no clear purpose or objective of how the data will be used to support response 2017-261 INTERNATIONAL OIL SPILL CONFERENCE 2017 2 operations. In this paper we review the use and misuse of SCAT in several recent smallscale incidents and discuss the implications for the wider implementation of SCAT moving forward.