Tag: fish

Lab Experience during a Pandemic

On By Roz GillisIn Projects, Research

Adam Andrews, Department of Biological, Geological, and Environmental Sciences, University of Bologna, Italy

Rachel Winter, Groningen Institute of Archaeology, University of Groningen, Netherlands

Willemien de Kock, Groningen Institute of Archaeology and Groningen Institute of Evolutionary Life Sciences, University of Groningen, Netherlands

SeaChanges project

SeaChanges (2019-2023) is a MSCA-multidisciplinary international training network of 15 PhD projects exploring long-term perspectives on the exploitation of marine vertebrates by integrating archaeology and marine biology. As a part of the training provided by the network, students undertake research secondments. Here we provide an account of our experiences at the University of York (UK) to complete collagen extraction and stable isotope analysis to contribute to our projects. 

To briefly acquaint you with our projects, small summaries are provided below.

ESR 12 – Adam Andrews, University of Bologna, Italy. I am investigating adaptation in Atlantic bluefin tuna (Thunnus thynnus) throughout the last 6000 years in the Mediterranean and Black Sea. I combine genomics, isotopes, and morphological analyses to understand how adaptable this species was/is and how resilient it remains now which may allow us to predict how it may respond to future change. 

ESR 13 – Rachel Winter, I am based at the University of Groningen in the Netherlands and am combining traditional zooarchaeology (NISP, osteometrics) with biomolecular archaeology (proteomics, stable isotope analysis) and marine ecology to understand the exploitation of groupers (Epinephelus spp.) in the Levant from the Bronze Age through the Hellenistic period. 

ESR 14 – Willemien de Kock, also based at the University of Groningen I study the foraging ecology and genetic connectivity of ancient green turtles (Chelonia mydas) along the Levant. Sea turtle bones are found at various archaeological sites, but my research focuses on remains from Kinet Höyük (Turkey), Tell Fadous-Kfarabida, and Tell el-Burak (both in Lebanon).

Lab Experience during COVID

Conducting lab work during a pandemic is certainly a peculiar experience.

It was a trip that was stressful before it began; for the Groningen delegation it meant traveling despite the government advice. We discussed the most responsible route and decided to cross the North Sea by ferry from Rotterdam to Hull. Sea turtles are always complicated to send across borders as they are endangered and listed on CITES, even old bones require proof that they existed before the animal was added to the CITES convention (a condition which we satisfy by several thousand years!). Willemien managed to courier them to York just before Brexit officially kicked in on the 1st of January 2021 saving her from more paperwork, phew! Rachel however crossed the sea with extra luggage consisting of ancient Mediterranean fish (none are on the CITES list!), it’s a glamorous life.

Due to the pandemic, acquiring samples has been predictably challenging. Closures to museums and institutions responsible for granting permission to destructively sample these materials, has resulted in delays to this project where only a subset of samples have been analysed to date. Fortunately, bluefin tuna are not listed on CITES which would have complicated matters further. 

Upon arrival into the UK, there were mandatory quarantine periods accompanied by the stress of hoping the courier finds the house and picks up our at home COVID tests, waiting for those results (negative, thankfully!), and then being permitted to arrange starting lab work. Once lab work commenced with regularity there are new considerations to going into the lab versus in non-covid times. For example, having to complete all of your training with colleagues at least 2 metres away and only being permitted a finite number of people in a space at any given time. To orchestrate all of this and ensure necessary precautions were taken, this further involved signing up on booking sheets for time slots in lab spaces, getting tested for covid twice a week, and when space was limited, working in slightly atypical spaces (casting sidelong looks to the zooarchaeology laboratory).

Of course, for one of us (the Englishman), quarantine was a relaxing (and merry) stint at home over the Christmas break.

Whilst we could access lab space and prepare samples for isotopic analysis, the experience was (not shockingly) simply incomparable with pre-pandemic times. Despite this, we still shared jokes in the lab that lightened the mood and made us feel very welcome and positive about the research. Even with so few colleagues around, we were very well supported when teething problems in new protocols/equipment arose and are grateful to everyone in BioArch at the University of York for enabling us to complete our lab work as planned.

Come plague, come ice and snow..samples will be processed,
Adam (left), Rachel (center) and Willemien (right) in front of York minster.

The three of us managed to extract collagen from an impressive number of samples (nearly 500 in total) and we were lucky that the York BioArch crew were so patient with us especially when we were using ALL of the test tubes. There was not much else to do except work, but eventually that played to our advantage when we saw the collagen come out of the freeze-drier looking exactly like cotton-candy – admittedly not as sweet but just as satisfying.

Stay tuned for the results coming to a journal near you!

Fish for the City

On By suzannebirchIn Research

We’re back with new blog posts after a short summer hiatus. Our first post of the academic year (which has already begun for some of us in the US!) comes from David Orton, who is currently an Early Career Research Fellow on the EUROFARM project at University College London, where he is also a Teaching Fellow in Zooarchaeology. Here he shares research that was conducted during his previous postdoctoral fellowship at the McDonald Institute for Archaeological Research at the University of Cambridge, which was recently published in Antiquity.

—

A Meta-analysis of Archaeological Cod Remains as a Tool for Understanding the Growth of London’s Northern Trade

The backstory to this research comes in two parts. First, a landmark zooarchaeological study by James Barrett and colleagues (2004) demonstrated an explosion in marine fish consumption in England within a few decades of AD1000.  Before this event – dubbed the ‘Fish Event Horizon’ (FEH) in tribute to Douglas Adams – sea fishing seems to have been rare and small-scale.

http://creativecommons.org/licenses/by/3.0/
Potential source regions and isotopic signatures for archaeological cod bones. Cross-hairs show one standard deviation ranges. Images taken from Orton et al. 2011 under CC BY license.

Second, James and his team applied stable isotope provenancing of cod bones to test whether this FEH represented a local phenomenon or the early onset of long distance trade from northern waters (full disclosure: I joined the project towards the end of this stage, in 2010). δ13C and δ15N signatures were established for six potential fishing regions using 259 samples from more than 10 countries. Applying this ‘target’ specimens from 23 (post)medieval sites around the North Sea (Barrett et al. 2011) and Baltic (Orton et al. 2011), we showed that a significant trade in northern cod existed by the 13th-14th centuries, but that the initial FEH in England primarily entailed local fishing. This raised more questions: when exactly did the trade start, how suddenly, and did the imported fish supplement or replace local catches?

Our new study, just published in Antiquity, combines a new zooarchaeological meta-analysis with the existing isotopic results to tell a clear story regarding cod imports to the city of London. Both elements rely on the same principle: that cod were traditionally decapitated before preservation for long-range trade, and that cranial elements thus normally represent relatively local catches. This allowed us to use head bones to establish regional isotopic signatures in the previous isotope work, but it also means that the cranial:postcranial ratio in consumer sites like London can be a rough index for the relative contribution of imports. We simply compiled all the raw data we could find on well-dated cod bones – almost 3000 specimens from 95 sites, including large datasets from Alison Locker and from MOLA – and plotted it using context-level date ranges.

http://creativecommons.org/licenses/by/3.0/
Stable isotopic provenancing results for 34 archaeological cod vertebrae and cleithra from various London sites (A; data from Barrett et al. 2011) set against AD 700–1700 detail of the estimated frequency distributions (B). Figure taken from Orton et al. 2014 under CC BY license.

The data show a very sudden switch to imports in the early/mid 13th C, with frequency of cranial bones dropping off just as the number of vertebrae increases sharply. This fits the isotopic results remarkably well: before about AD1250 almost all sampled specimens seem to be local; afterwards the majority are probable imports. Locally caught cod thus seem to have been substantially and rapidly replaced in Londoners’ diet by traded fish almost 800 years ago. What this meant for the local fishing industry is uncertain, but should become clearer when we look at other towns and species.

Biomolecular provenancing has a unique ability to provide direct evidence for the source of imported bones, but its cost and destructiveness ultimately limit sample sizes and hence the reliability and resolution of the stories it can tell. Integrating it with the much larger samples that can be marshalled from meta-analyses of conventional zooarchaeological data has great potential to overcome this problem.

REFERENCES

Orton DC, Morris J, Locker A and Barrett JH (2014) Fish for the City: meta-analysis of archaeological cod remains as a tool for understanding the growth of London’s northern trade. Antiquity 88, 516-530.
[link: http://antiquity.ac.uk/ant/088/ant0880516.htm%5D

Orton DC, Makowiecki D, de Roo T, Johnstone C, Harland J, Jonsson L et al. (2011) Stable Isotope Evidence for Late Medieval (14th–15th C) Origins of the Eastern Baltic Cod (Gadus morhua) Fishery. PLoS ONE 6, e27568.
[DOI: 10.1371/journal.pone.0027568]

Barrett J, Orton D, Johnstone C, Harland J, Van Neer W, Ervynck A et al. (2011) Interpreting the expansion of sea fishing in medieval Europe using stable isotope analysis of archaeological cod bones. Journal of Archaeological Science 38, 1516-24.
[DOI: 10.1016/j.jas.2011.02.017]

Barrett JH, Locker AM, and Roberts CM (2004b) The origins of intensive marine fishing in medieval Europe: the English evidence. Proceedings of the Royal Society of London. Series B: Biological Sciences 271, 2417-21. [DOI: 10.1098/rspb.2004.2885]