Potential contribution of terrestrial Organic Matter to the Arctic food web

To better constrain the fate of terrestrial ON in the Arctic Ocean, we seek a
mechanistic insight of terrestrial ON cycling during cross-shelf transport. The studentship will test
the hypotheses that:
1) The bioavailability of terrestrial ON is source dependent i.e. river vs. ICD, and
2) The isotopic composition of N in the sedimentary HAAs of S-N transects of the ESAS reflects
the transport of terrestrial ON offshore (i.e. a gradient in 15N of the conservative HAA,
phenylalanine).

The main beneficiaries of this project will be policy makers concerned with conservation of Arctic marine mammals, Inuit communities, school pupils, teachers and the wider general public.

Throughout much of their range, seals and other mammals are important cultural and nutritional resources for indigenous and non-indigenous communities. However, seals are being measurably impacted by climate change. Our project will provide observational and modelling evidence regarding the drivers of alterations to seals' trophic position, food web structure or foraging behaviour over decadal time scales. Using multiple tools, we will delineate if changes in seal trophic position, food chain length or foraging behaviour are due to environmental factors (e.g. sea ice changes), variations in the base of the food web (e.g. from reduced nutrient supply) or the addition of new trophic levels (e.g. migration of boreal species). Our work directly benefits ongoing programmes that monitor the Arctic, such as the Five-year Science Research Agenda from the Department of Fisheries and Oceans (Canada). Our work will benefit work by DFO and aid Inuit communities develop adaptation strategies (Letter of Support from Ferguson, DFO). We will disseminate results from our project to key international organisations, such as the International Council for Exploration of the Seas (ICES) and North Atlantic Marine Mammal Commission (NAMMCO), facilitated by NAMMCO General Secretary and project partner, Desportes. Other project partners (Stenson, Hammill, Ferguson and Hop) are also involved in ICES and NAMMCO, as well as the Circumpolar Biodiversity Monitoring Programme (CBMP), making them able to disseminate our results in the context of management and policy. A one year PDRA will collate, analyse and model historical data on harp and ringed seal body condition and fecundity alongside environmental variables and determine the factors driving long term change in seal populations, disseminating their findings to ICES and NAMMCO at international meetings. This will allow the practical and applied project outputs to inform management and policy for marine mammals in the Arctic, with the potential to affect future decision making for seal populations. Thus, we directly address NERC strategy by providing tools for the 'Management of Environmental Change'.

It is essential that our research outcomes are disseminated to the UK community. This is challenging but vital to recruit students into sciences, convince the public that it is worthwhile funding this type of research and increase awareness of the sensitivity of the Arctic to a changing climate. Our project will provide teachers with tools to demonstrate key concepts in our research programme. To this end, we will produce three posters to convey for example, 'Arctic food webs', 'Stable isotopes in Arctic ecology' and 'Impact of climate change on the Arctic' to school pupils in order to demonstrate how food webs operate in the Arctic. Posters will be hand-drawn by a visual artist with experience of communicating complex ideas concisely and digitized by co-PI Heath.

The general public tends to engage with popular wild life television programmes that illustrate the fauna of the Arctic and the pressures imposed by climate change. We will explain the vital role of microscopic phytoplankton and nutrients within the environment by creating one short accessible scored video, with combinations of film, hand and digital animations with commentaries aimed at the general public. The video will be distributed via a project YouTube channel and via our own website.

At the programme level we suggest (a) creating a dedicated programme website and social media outlets, (b) soliciting the BBC or Discovery Channel to produce a short documentary about the programme and (c) hiring an expert in science communication and impact to represent the programme and/or train members of the research programme in science communication.