Can shipwrecks boost marine biodiversity?

Shipwrecks might not seem like a positive feature of the ocean floor. They are man-made remnants, generally resulting from incidents or even disasters at sea, and yet in many cases they are recognised as cultural heritage sites. When we look more closely at shipwrecks and other underwater cultural heritage sites, such as, old abandoned harbours, it seems that they could have a positive impact on biodiversity and promote conservation of marine environments in line with international targets. 

These are the findings of an interdisciplinary project at the UI Research Centre in Bolungarvík, completed in partnership with the Marine Research Institute, which were recently published in the journal Marine Policy. 

The authors of the article recently posted on social media:

 “There are over 3 million shipwrecks on the ocean floor – and many other cultural heritage sites. They help us better understand the past, but they could also have an important role to play in environmental conservation. A newly published article in Marine Policy analyses the protection of underwater cultural heritage sites in Iceland. It discusses whether they could be used to help deliver the UN SDGs, which aim at protecting 30% of the ocean by 2030. Many shipwrecks may form “natural” biodiversity havens – sometimes within areas of high intensity trawling.”

Interdisciplinary approach is the key to new perspectives

The UI Research Centre in Bolungarvík has attracted attention in the world of ecological research for the way in which scientists from different disciplines have worked together to produce fascinating results, which would not have otherwise been achievable. This is one such study.

“I noticed during my research into the distribution and movements of fish, especially juvenile cod, that there seemed to be many more juvenile fish at underwater cultural heritage (UCH) sites, e.g. old harbour sites and shipwrecks. This was my personal observation and has not been tested, but nevertheless I became  interested in looking at underwater cultural heritage and biodiversity together. There have been many studies abroad showing that biodiversity is higher around shipwreck sites,” says Guðbjörg Ásta Ólafsdóttir, biologist, director of the Research Centre and one of the three authors behind the paper. The other authors are Ragnar Edvardsson, an archaeologist at UI who has specialised in underwater research, and Einar Hjörleifsson, a scientist at the Marine Research Institute.

Remote sensing techniques used to map shipwreck sites

The study used a range of different research methods. The scientists used historical records of shipwrecks and remote sensing techniques to confirm and map UCH sites.  They also examined various available data from the fishing industry. Remote sensing is a fast-growing field of research, used to map various objects or phenomena from a considerable distance. Satellites, aeroplanes or drones are used to gather data, which is then processed using computers.

“First we needed to identify appropriate sites to analyse and for this we relied on Ragnar Edvardsson’s extensive database of wrecks off the coast of Iceland,” says Guðbjörg. We were then able to use Einar Hjörleifsson’s existing analyses of data from fishing vessel monitoring systems to look at fishing pressures at the UCH sites. We also analysed Icelandic heritage law and policy, reviewed media coverage and case reports, and interviewed representatives from government agencies.

Ragnar Edvardsson, who works at the UI Research Centre in Bolungarvík, has many years’ experience of underwater archaeology, including excavations of old fishing stations and abandoned whaling stations around Iceland. He has also done considerable work mapping shipwrecks using written sources, which has revealed 1,144 geolocated wrecks around the Icelandic coast. 

“We have investigated many of these wrecks from various historical periods. They are often very well preserved and sites of remarkable biodiversity,” says Ragnar. 

This study shows that UCH sites present a wonderful opportunity for biodiversity protection. “From the perspective of heritage conservation,” says Ragnar, “the study shows that the legal framework for protecting UCH sites is already in place, but government agencies need to increase their focus on this area, i.e. research and registration, since we anticipate increased risk from various activities in the coming years.” 

A completely new approach to the data

This research is truly innovative in its approach to analysing and using data. “I believe that all marine conservation research in Iceland is novel, since there has been far too little work in this area,” says Guðbjörg. 

“Internationally speaking, this study is innovative in the way that we connect data about UCH sites, the legal framework of heritage conservation, and the movements of fishing vessels. This is a novel approach in this context. We also looked at data from a wide range of sources, including legal case reports, interviews with government agencies and analysis of media coverage over a long period.”

Iceland is an ideal location for analysis like this, since the data is easily accessible and there are generally open communication channels between researchers and government agencies. Another unusual thing about the study was that the team comprised only these three scientists, who worked together very effectively in an interdisciplinary way.

“We saw that, despite the potential, the lack of coordinated information sharing and formal integration with planning and conservation systems reduces the potential value of UCH sites as protected areas.”

Important conclusions that will support conservation

With increased cooperation between agencies involved in heritage conservation, environmental conservation, ocean and fishing vessel monitoring, UCH sites could be a low-hanging fruit to help the government meet marine biodiversity goals. 

“This could actually be achieved immediately for coastal heritage sites – hardly any systemic changes would be required, just simple site studies to confirm their ecological value and better information sharing across agencies and with stakeholders,” says Guðbjörg. 

She is keen to continue research into the planning of protected marine areas, in particular the human aspect – finding out the perspectives of different stakeholders and working with them to collect data. “Nearly all the research on this this shows that the best results are achieved through involving a broad group of stakeholders, dialogue and cooperation. We Icelanders have a long way to go to develop a comprehensive system of marine protected areas that ensures sustainable exploitation. So there’s plenty left to do in this area.”

Guðbjörg and Ragnar plan now to continue their work directly measuring biodiversity around registered UCH sites – and they already have a few specific sites in mind. “This research also fits in very well with another area that I have been doing a lot of work in, namely tagging fish and measuring their movements in shallow coastal waters.”