MESOPELAGIC FISH MAY PLAY ROLE AS A FOOD OF THE FUTURE
Mesopelagic fish may play role as a food of the future. Utilising new marine resources though aquaculture and harvesting, without undermining ecosystem health, is one of the priorities of the Ocean Panel’s Agenda for Ocean Action.
This is also one of the topics under discussion at this year’s North Atlantic Seafood Forum (NASF), June 8th–10th.
More food from the ocean
“More than 3 billion people rely on food from the ocean as a source of protein and nutrition. This number can grow in the future, as the ocean could supply over 6 times more food than it does today under sustainable science-backed practices,” says Peter M. Haugan, Programme Director for Global Development at the Institute of Marine Research (IMR) and one of the keynote speakers at NASF.
The numbers come from one of the Blue Papers commissioned by the Ocean Panel, where Haugan served as co-chair of the Expert Group. As their report makes clear, much of the projected growth in aquatic food will have to come from resources that are currently not utilised or underutilised.
These include mussels and other low-trophic species that can be farmed without active feeding. But also the abundant deep-water or mesopelagic species such as krill and small fishes are being considered for food or feed.
Investigating effects on obesity and diabetes
One of the hurdles that have to be cleared before these new resources can be used at scale, however, is to map their potential impact on our health as well as the environment.
This is the focus of a five-year research project at the IMR. In one ongoing experimental study, mice are used as models for humans to study health effects.
“In particular, we want to see if the new marine resources can have the same beneficial effects as traditional seafoods on the development of obesity and type 2 diabetes,” explains Atabak Mahjour Azad, a postdoctoral researcher at IMR.
The mice were fed three different mesopelagic species: Mueller’s pearlside, glacier lantern fish, and Northern krill. Other mice in the study were fed blue mussels, as well as salmon that had been fed blue mussels; some also got standard seafood or land-based feed.
Different nutritional contents
“We fed these different ingredients to ten mice in each group and measured their weight each week. After eleven weeks, we saw that the weight gain was different among the different groups,” says Azad, who led the study together with Lise Madsen.
In preliminary results, they found that mice that were fed Mueller’s pearlside gained significantly more weight than the ones that were fed glacier lantern fish in the trial.
“From previous studies, we know that these mesopelagic species have different nutritional content. Most importantly, they contain different types of fat. These fats may have different levels of digestibility, and this could partly explain the results we have found so far.”
However, some of the difference could also be due to the mice’s appetite for Mueller’s pearlside. Researchers found that mice in this group ate slightly more of their feed than the others.
“This is a preliminary result, so we have to do more detailed analyses to correct for differences in feed intake among other things,” Azad adds.
Researchers dig into the mesopelagic zone
The study comes on the heels of a spate of recent research on mesopelagic species at IMR in recent years, both on their abundance in Norwegian waters and their potential contribution to food and feed security, including potential food safety issues.
One study of the nutrient composition of six species found that several species proved to be nutrient dense.
“In short, the nutrient content is similar or higher than in fillets from the fish we often eat, such as salmon and cod. And largely higher than in blue whiting, which is widely used as an ingredient in salmon feed,” concluded researcher Martin Wiech.”
A sustainable ocean economy can support development
Much work still remains to be done. Meanwhile, the knowledge generated by this research will help to inform markets and governments on how mesopelagic and low-trophic resources can be used in the food systems of the future.
If done in a cautionary and science-based way, these resources can provide new, sustainable sources of income and nutrition for both developed and developing countries. This is one example of how ocean science and management can support global development, as highlighted by the Ocean Panel.
“The ocean isn’t just a victim of human activity. A healthy ocean is critical to solving global challenges,” says Peter M. Haugan.
Author: Runar Bjørkvik Mæland