Drivers and barriers of technological innovation in the Norwegian bottom trawler fleet,1960s–2025

Abstract

The oceangoing bottom trawler is the largest vessel type in the Norwegian fishing fleet. It is important to the Norwegian economy but has a controversial position in the public debate. Fishers have always had to adapt to change, and innovation is generally seen as a way to do so. However, examining the design of the bottom trawler reveals that while there have been numerous incremental developments, the concept has not changed since its introduction to the Norwegian fishery in the 1960s. Supported by empirical evidence collected through 12 semi-structured interviews with senior representatives of firms in the trawling industry, this article presents the recent historical development of the design and factors influencing this development. An outlook on current challenges and opportunities is given, concluding that a completely new way of thinking is required to accommodate disruptive innovation on the bottom trawler.

Introduction

The oceangoing bottom trawler is the largest vessel type in the Norwegian fishing fleet. ¹ These vessels capture marine life by dragging a net, called a trawl, through the water. The main target species for this fleet group in Norway are cod and other whitefish such as saithe and haddock. When filled, the trawl is dragged on board over a ramp at the stern, after which the catch is deposited into a receiving tank for processing in the factory on board. Various product strategies are employed, from filleting on board to supplying headed and gutted or round fish. Products are generally frozen on board, but most vessels also have an option to store fresh fish on ice. In addition, most vessels have the ability to fish for shrimp, something which is often done in the off-season to keep the vessel active when its whitefish quota runs out. ²

In general, the seafood industry is important for the Norwegian economy, second only to oil and gas in total export revenue. Norway exports the largest amount of seafood per capita in the world. While most of the export value comes from aquaculture, the capture fisheries remain a significant industry. ³ The Norwegian fishing fleet directly employs around 11 000 people and is responsible for a further 6000 workplaces in ripple-effects. ⁴ Fishing, and more generally the use of the sea, is also important culturally, with what the sea has to offer shaping the Norwegian people. ⁵

With fish being a varying resource, fishers have always had to adapt to changing framework conditions. This includes the availability of fish stocks, technical regulations, and political changes. Innovation is generally seen as a key element in adapting to change.

Examining the design of the oceangoing bottom trawler, however, reveals that the concept of this type of vessel has not changed since its introduction to Norwegian fisheries in the 1960s. While there have been numerous incremental improvements in the systems on board, the general method of working is the same as before. Fish are still caught by dragging a net through the water and the catch is dragged on board over the stern ramp, after which it is processed and frozen for delivery to land. This apparent lack of fundamental technological innovation is intriguing, as Norway is known as a highly technologically advanced country.

Additionally, there exists limited academic literature on this fleet segment. This could be explained by the small size of the fleet, which makes it less interesting for researchers to do research on these kinds of vessel. It is also likely that researchers in fisheries at a local scale prefer to publish in national journals in native languages, leading to accessibility issues for international scholars. ⁶

Furthermore, trawling has a controversial position in the public debate when compared with other fishing methods. Contributing to knowledge sharing and dissemination of facts is important in this context. While we do not explicitly go into the effects of public opinion in this article, it is important to note that this always plays a role in the diffusion of technology, either directly or through influencing politics and regulation.

We believe that presenting the recent historical development of the oceangoing bottom trawler in Norway, and moreover identifying reasons for this development, is beneficial for those involved in the design of the vessels and the management of the fishery alike.

We therefore attempt to answer the following research questions:

How has Norwegian oceangoing bottom trawler design developed since the 1960s?

Which drivers and barriers have influenced technological innovation in the fleet?

Our scope is the oceangoing bottom trawler fleet that is operated by Norwegian owners. There are 39 vessels of this type, ⁷ which is relatively few considering a total number of active fishing vessels of around 4600. Despite the small number of vessels, the oceangoing trawlers stand for 35% of the catch volume and 55% of the catch value for the main whitefish species. ⁸

It should also be noted that the literature is ambiguous in the definition of several different sub-types of bottom trawlers. The main distinction can be seen as between ‘factory trawlers’ and ‘freezer trawlers’. Some refer only to those vessels that produce fillets on board as factory trawlers, while others include any vessel that does some form of processing on board. All bottom trawlers in Norway do some form of processing on board, but producing fillets on board is strictly regulated, and today only three Norwegian trawlers do so. ⁹ In this article we include both types of bottom trawler but aim to retain the distinction between the two.

This study employs a qualitative research method that combines secondary data from academic publications, reports and reliable media sources with primary data from 12 semi-structured in-depth interviews. An iterative approach to data analysis is employed, where first the empirical data is reduced using open coding, after which it is categorised based on analysis of relevant themes discussed during the interviews.

This process results in a concise and structured overview of changes in the design and an analysis of drivers and barriers to technological innovation, respectively answering research questions one and two. The analysis is rooted in the concept of sociotechnology, which expresses that technological innovations are not developed in a vacuum but are developed in a social process where economic and political factors also shape the development. This implies that technological innovations are part of an open and complex social system, which may either inhibit or promote development, a characteristic that is expressed through the notion of path dependence.

Finally, the results are discussed and an outlook on the future of the oceangoing trawler design is given by highlighting current challenges and opportunities. An example of a significant recent delivery that has the potential to change the industry as a whole is commented on.

Literature review

Development of an industrialised Norwegian fishery

The earliest accounts of trawling as a fishing method stem from fourteenth-century England, first exclusively by beam trawl. ¹⁰ In the next centuries, the invention spread to other countries around the Atlantic. It was not until the end of the nineteenth century, however, that trawling became a widespread commercial fishing method. This development can mainly be attributed to the introduction of the otter trawl, which uses planks called otter boards – later commonly referred to as trawl doors – to ensure the horizontal spread of the net. ¹¹

The first Norwegian vessel using such a bottom trawl was called Pericles, registered in Harstad in 1908. The trawl was set on the side at this time. While the project was given up after a few years owing to difficulties with the sea bottom presumably damaging the gear and difficulties in delivering the catch, it showed the potential of trawling as an industrialised fishing method. ¹² Nevertheless, immediate concern was raised about the bottom trawling practice in the early years, both amongst the local communities in Norway and in other countries around the Atlantic. ¹³

The larger first steps in industrialising the fishery could, however, be seen at the same time, when steam and motorised fishing vessels were introduced around the turn of the twentieth century. Change was rapid and in only two decades most of the sailing vessels were replaced by steam-powered ones. The oceangoing vessels were hesitant to install combustion engines at first, even though the lower investment costs and greater simplicity of use were well known. Nevertheless, the technology spread along the coast in the years that followed. ¹⁴ For both steam and combustion engines, the significant cost of acquiring the new technology sparked the creation of special loan funds from various sources: (local) government, banks, and informal lending. ¹⁵

After World War II, a large part of the European fishing fleet had been destroyed or converted for other use. At the same time, there was a huge demand for food across Europe. The introduction of cooling and freezing equipment on board meant that vessels could fish further out at sea for longer periods of time. The rise of the oceangoing trawler, hauling catch over the stern and freezing the products on board, marked a complete shift for the industry, such that it can be seen as a second industrial revolution in the fishery. ¹⁶

In Norway, the introduction of oceangoing bottom trawlers was seen as a key element in the rebuilding of coastal communities. The trawler fleet was designed to serve a land-based processing industry in a vertically integrated strategy, presented in 1959. This round of industrialisation of the cod fishery could only happen because of a large amount of public financial support from the government. This came under the condition that the trawlers delivered their catch to specific processing plants under a fixed minimum price. The result was that the industry-owned trawlers were never profitable and needed constant government support. ¹⁷

In the meantime, others were experimenting with producing fish fillets on board the trawlers. The first factory trawler was Longva (1962). The ship employed a crew of 50, of whom half solely worked in the fillet production in the factory. While on board production of fillets was not new – there are examples of longliners in the 1920s and 1930s doing so – Longva was the first vessel to fillet fish on such a large scale. ¹⁸ While scepticism throughout the fisheries districts was profound, experience with the new vessel was positive and many such factory vessels followed in the 1970s and 1980s. ¹⁹ Moreover, the factory trawlers had been profitable since their introduction to the fishery and were seen as the main enemy to the coastal vessels and land-based industry. Nevertheless, the number of factory trawlers has reduced drastically until today. Reasons for this are strong institutional change, stagnation of technology, and loss of competitive advantage as the less costly process of producing headed and gutted fish was further developed. ²⁰

The ‘discovery’ of oil on the Norwegian continental shelf in 1969 meant that, eventually, the fishing companies were competing with the offshore sector for crew. It is obvious that this competition drives the fishing companies to improve the working conditions on board, and vice versa. The exchange of personnel also means that competence is shared between the two industries. ²¹ A similar point can be made for the rise of the sea-based aquaculture industry, with knowledge from the fishing industry being a significant contribution to both technological and organisational development. ²²

Followed by the decline in the cod stock during the 1980s, the introduction of individual vessel quotas and reduction of public financial support led to the desire to reduce the unprofitable overcapacity of the industry-owned trawlers. Various reforms of the quota system in the following decades allowed trawler owners to concentrate more and more quota on a single vessel. ²³ This has resulted in a drastic reduction in the number of bottom trawlers: from over 150 in 1980 to 39 today. Another result of this is that the individual vessels have grown in catch capacity and the catch per fisher has increased. The last aspect is illustrated in Figure 1, ²⁴ which shows a close to 10-fold increase in the catch per fisher between 1960 and 2025. It should be noted that these numbers are for the entire Norwegian fishing fleet, as it is challenging to estimate the total catch and number of fishers employed separately for a single fleet group. Still, the trend throughout each fleet group has been similar, where efficiency measures have contributed to fewer fishers fishing a relatively constant total catch amount.

Figure 1.

The increasing trend of catch per fisher for the entire Norwegian fleet. Left axis: number of fishers (dotted line) and catch per fisher in kilograms (solid line). Right axis: total catch in tonnes (shaded area).

In recent times, the increasing introduction of sensor technology and a clearer focus on data have changed the profession of fisher into a ‘regulated specialist’. ²⁵ What thus remains today is a small fleet group that delivers large catches with high value. The intensity of the fishery has in that sense increased, something that may put further pressure on technological innovation.

Technological innovation in the social context

A broad definition of technological innovation is the process of ‘creative destruction’, where new technologies replace established ones with the aim of increasing performance, efficiency or functionality. A distinction is made between disruptive and sustaining innovation, where the variable is the degree of change a new technology incorporates. A disruptive innovation is one with a high degree of change, which may underperform initially but has the potential to eventually redefine markets. A sustaining innovation, on the other hand, is one that does not significantly affect the existing market, either because it merely improves an existing solution or because it only reaches a limited group within the market. ²⁶

Technological innovations are never developed in a vacuum but are always contingent on the social context. This is expressed in the concept of sociotechnology as explained by Bijker, who highlights that ‘it is not only engineers but all relevant social groups who contribute to the social construction of technology’. ²⁷ That is, technological innovations are not only a technological process but also a social process where economic and political factors shape the historical development of innovation.

This plays a part not only in the development of new technology, but also in the assessment of the implementation of a technological innovation. It is important to note that different social groups carry different interests, values and norms. ²⁸ Therefore, what is seen as a successful innovation to one group may be seen as a threat to the way of living of another group. It is thus not enough to explain the success of a new technology by saying that it is simply ‘the best’ – the criteria that the various relevant social groups consider for ‘being the best’ must be considered. ²⁹

The sociotechnology perspective implies that the technological solutions that are historically built into a certain industrial structure may inhibit new development paths that break with the existing structure. In other words, they become subject to path dependence that restricts the degree of change that is possible. ³⁰ In the same vein, the view on institutions and organisations as carriers of history explains their persistence. ³¹ They establish conventions that facilitate coordination, develop codes that facilitate communication, and create interdependences, discouraging changes in one part of the system that may lead to disturbances in other parts. Such mechanisms commonly associated with path dependence are self-reinforcing: they reproduce patterns of events over time and keep them moving along a particular track. They may alternatively be reactive: initial disturbances trigger powerful responses that shift the path into a new direction. ³² Since social systems are open systems, their historical structures may be both constraining and enabling, and they may be either reproduced or transformed by the actors involved. However, as over time these structures gain momentum, actors are bound to struggle when developing new technological solutions. ³³

Using the broad definition of path dependence presented here, we can say that innovating is equivalent to ‘breaking the chain’: making a change that influences the future path.

In a similar fashion to Castillo and Valdaliso, ³⁴ we analyse three broad types of factors influencing technological innovation in this article: economic, technological, and institutional factors. In this context, we distinguish between drivers and barriers, where the former are factors that seem to promote innovation and the latter are factors that seem to inhibit innovation.

Economic factors include the market, profitability of operations, investment capability and globalisation.

Technological factors influence technological innovation as well. Here, we go into cross-industry innovation, pilot projects, technological maturity and technological complexity. Amongst institutional factors, we identify the regulatory framework, the organisation of the industry and the influence of other relevant social groups that are affected by or have an influence on technological change, such as the crew or the public.

Methodology

This study is built on both primary and secondary data. To shed light on the recent developments, this study employed a qualitative research method to collect primary data, with a purposive sample of 12 firms in the Norwegian maritime industry. The empirical material was collected through in-depth semi-structured interviews with senior representatives from each of the firms, who were deemed as especially knowledgeable respondents considering their positions in the firms. The primary data were supplemented where deemed necessary with secondary data from academic publications, research reports, and reliable media sources.

Purposive sampling was chosen because it allows for selecting participants based on their prospective relevant knowledge and going into depth, rather than aiming for statistical representativeness. This fits well with our intention of exploring the historical development and reasons for this development from the industrial perspective offered by the selected participants. Most of the respondents were accessed through the researchers’ network in the maritime cluster, while the remaining few were identified and contacted through ‘snowballing’. The contacting of new participants was stopped when data saturation was thought to be reached, the point in data collection where new participants were repeating aspects that had already been named in previous interviews.

The used sample represented three categories of actors to touch upon the variety of views in the industry, constituting six ship owners, four ship designers, and two equipment suppliers. Most of the sample firms are located on the western coast of Norway.

The interviews were carried out over the spring and summer of 2024. All interviews but one were conducted in person, with the last one carried out digitally owing to the geographical distance. Most interviews were conducted by a team of two researchers, which enhanced the conversation flow, allowed for observations and note-taking, and ensured that all the intended topics were covered. To further aid this, an interview guide (which is included as supplemental material) was used. The interview guide served as a rough frame for the conversations, where departures from this frame were natural and allowed. For consistency, one of the researchers was present at all the interviews.

Face-to-face interviewing enhanced the quality of communication and helped to build rapport with the respondents, which in turn contributed to openness in the conversations. Most respondents were proficient in English, so it was used as lingua franca in most of the interviews, while three of the respondents preferred to use their mother tongue of Norwegian. Although those speaking English did not seem to experience any difficulties with language, the richness of expression could be lost to some degree.

The conversations were recorded and had an average duration of one hour. Later, the recordings were transcribed verbatim in their respective languages. The transcriptions were then anonymised such that no statements could be led back to an individual. Where excerpts are presented in this article that came from the Norwegian-language interviews, they have been translated by one of the researchers.

Two of the researchers were actively involved in analysing the primary data, with the aim of eliminating personal bias. An iterative approach to data analysis was employed. In the first iteration, open coding was used to systematise and reduce the data. Then the codes were grouped into categories based on identifying relevant themes discussed across the interviews. The information was split between useful for the historical development (Section 4) and useful for analysis of the reasons behind these developments (Section 5). In a final iteration, the information containing the reasons for development was structured following the theoretical framework presented in Section 2.

Data were collected and handled in accordance with the regulations of the Norwegian Agency for Shared Services in Education and Research.

Historical development

Ships are complex, consisting of various systems with different functions that interact with each other. It is therefore beneficial to split the ship into these distinct systems in order to outline development in each of them. Here, a division is made between payload systems and ship systems. Payload systems are those related to cargo – that either directly or indirectly contribute to creating value on board. Ship systems are those that are required to operate the vessel and can be seen as supporting the payload systems. ³⁵

For the bottom trawler, we categorise the systems as shown in Figure 2, where most systems are roughly placed in their physical areas shown in Figure 3. This distinction is used to outline the historical development in the following subsections.

Figure 2.

Payload systems and ship systems for a bottom trawler with a list of components/technologies related to these systems.

Figure 3.

Payload systems and ship systems for a bottom trawler roughly placed in their respective areas.

This section is built on the primary data collected and supplemented with secondary data where deemed necessary. Each subsection starts with a brief description of the system, then outlines trends that have happened, and gives specific examples of innovation on board.

A. Capture

Trawling is an active fishing method that involves dragging a net through the water in order to catch the marine life it encounters. There exist various types of trawl gear, such as the beam trawl or Danish and Scottish seine. However, the type universally used by oceangoing bottom trawlers and thus of focus here is the otter trawl, which uses two doors at either side of the net to keep it open during towing. The capture system as we define it consists of the trawl gear: the netting and connected components that are responsible for capturing and retaining the catch.

In the same trend as the vessel, the trawl itself has generally increased in size. At the end of the 1990s, experiments with a double trawl proved successful. Here, two trawls are mounted side-by-side, with a clump weight in the middle between the trawls and two trawl doors on the outside of the rig. The objective of this is to obtain a larger sweep area, while limiting the amount of netting compared with using a single large trawl – as the trawl needs to have a certain (triangular) shape. Around the year 2000, the first vessel operating a triple trawl came into operation. In this case there are two sets of doors (inner and outer), that act to keep all nets open. The illustration on the left of Figure 4 ³⁶ shows a triple trawl. Nowadays, the double and triple trawls are used mainly for catching shrimp.

Figure 4.

An illustration of a triple trawl (left) and a semi-pelagic single trawl (right).

Especially in the past two decades, there has been focus on the fuel and fishing efficiency of the trawl gear. This means reducing the towing resistance as much as possible, while keeping the sweep area large. Advanced methods such as computational fluid dynamics have aided this development. The trawl doors are the main point of attention in this development.

A major development in this context is the use of semi-pelagic gear (also called off-bottom gear), where the doors are lifted some metres from the bottom. An illustration is shown on the right of Figure 4. This development started with the CRISP project in 2011. ³⁷ While pelagic trawling for demersal fish in the Barents Sea had been prohibited in 1979 because of high bycatch of juveniles, the recent development in sensor technology and knowledge of what comes into the trawl has been a driver to change the regulation to allow it. From the interviews it is concluded that, today, some one-third of the fleet uses semi-pelagic gear regularly.

More recently, semi-pelagic doors with automatic height control have been developed. In this case, the captain can set a desired height above the bottom, where sensors and a control system keep the doors at that height. However, as one respondent explained, the added complexity of this system causes it to be expensive to invest in currently, and there are no examples of oceangoing trawlers using the automatic doors in operation yet.

New ground gear is also being developed constantly. One example is the semi-circular spreader gear, ³⁸ the development of which was motivated by ease of handling on deck as well as reducing environmental emissions. A more recent example is the Injector Flow Gear, ³⁹ which claims increased catch rates with a lower resistance. However, the material used is plastic, which is for some companies a reason to be sceptical considering the wear characteristics of ground gear.

The amount of sensor technology employed in the trawl has also increased massively. For example, the captain gets real-time information on the geometry of the trawl, as well as the filling rate of the codend. This helps when setting the trawl and during fishing, making the process more efficient when compared with the completely ‘blind’ fishing of earlier times.

B. Gear handling

The trawl deck is the first open deck on the vessel, which contains the slipway and trawl lanes. In fishing conditions, fishers are working on deck when rigging, setting and adjusting the trawl, as well as when hauling and lowering fish down to the processing deck. This is where the gear handling equipment is located, notably the trawl winches, blocks and cranes.

In the late 1970s, the trawl deck was extended to stretch almost the full length of the vessel. The amount of trawl lanes has also gradually increased in accordance with the ability to use a double and triple trawl. The general layout of the trawl deck has remained the same since the 1970s though, with the trawl lanes in the centre and working areas on the side of the deck. There are now regulations prescribing the clear marking of safe zones on the deck. In trend with the rest of the vessel, most deck equipment is electric today, which has allowed more freedom in the placement of equipment.

The trawl winches were traditionally placed on the side of the trawl deck, but with the amount and size of the winches growing, these have been placed one deck up. An added benefit of this is that the wires are now above the people working, reducing trip hazards and clutter on the trawl deck. This does have an impact on the stability, which means that the vessel needs to be wider when weights are moved up.

The winches themselves have seen a large development. Traditionally, winches were low-pressure hydraulic, which meant that a large amount of hydraulic piping needed to be placed across the vessel. In the past two decades, the development of electric winches has taken a great leap forward. First, this was traditional AC motors, with a gearbox. It then went to permanent magnet (PM) motors in the last five years, which do not require a gearbox. This means that both installation and maintenance are simpler, and there is a better control of the dynamics of the winch. Another benefit with PM winches is that, when shooting the trawl, the winches regenerate electricity, which can be used in propulsion. The price differences of these various winch technologies do, however, mean there are still new vessels being built with hydraulic systems, and the PM technology has not been adopted universally.

A large share of the fleet is equipped to fish in ice. A challenge in these conditions is that the warps of the trawl can get on top of the ice, lifting the trawl from the bottom. To limit this risk, a system is implemented that guides the warps to the centre of the vessel, where the ice has been broken by the propeller. These are called ice trawl davits, which can be adjusted transversally. Some vessels have used the system to aid in steering the vessel, as adjusting the davits asymmetrically provides a sideways force, which aids in limiting the amount of rudder required.

C. Processing

The processing factory is generally located on the main deck. In this area, the catch is processed into a stable product that is stored in the cargo hold. The main steps in the factory are receiving, killing, cleaning and sorting, freezing, and packaging.

In the past decade, quotas have been high. This resulted in a focus on increasing the capacity of the factory, while keeping the number of crew the same. Factors contributing to this are more automation, increased efficiency and the general size of the factory.

In the same time period, it has been more important to take care of the residual raw material – the head, guts, and offcuts – when producing fillets. Before, this was in many cases thrown overboard. There are two main options for taking care of residual raw material. The simplest is to grind and store it as ensilage in tanks by adding acid. Another option is to create fish meal and oil. There have been examples of vessels taking care of the residual raw material ever since the 1970s and there has been no universal choice of what process to use on trawlers. Additionally, specific parts of the fish, such as the head or skin, are in some cases separated and frozen. The choice of which parts to do this for depends on the price of the product, space on board and the availability the crew.

A major innovation, introduced in the late 2000s, was automatic heading–gutting machines. ⁴⁰ Using these machines, the factory worker only has to place the fish in the right orientation in the machine, which performs a number of cuts in series automatically.

Another more recent development is the use of water-cutting for fillet production. These machines identify the locations of bones and cut a boneless fillet. Tests on board were successful; however, the increased complexity and technical problems in operation led to the choice to not instal the machine on board. ⁴¹

In addition, some vessels have possibility of keeping the fish in the receiving tank alive, by supplying clean seawater with oxygen. This causes less stress on the fish and results in a better quality when it is processed. However, as one respondent noted, it is difficult for a customer to see the difference between fish that have been kept alive in the receiving tank and those that have not, so not many ship owners have this system on board.

Another development is stunning the fish with an electric shock as soon as it enters the factory. This reduces the impact of stress on the muscles, but a larger benefit is that the fish lies still when the crew member places it in the heading–gutting machine. Electric stunners were first introduced in the salmon industry on land and were introduced some 15 years ago on board the trawlers. From the interviews, consensus has been reached that more or less every vessel uses stunning on board today.

Bleeding fish before it is further processed also has a positive impact on quality and the process flow in the factory. Similar to keeping the fish alive in the receiving tank, however, it is not clear if the customer sees the difference between fish that have been bled and fish that have not. In addition, bleeding fish requires intermediate storage tanks that take space. It is thus not a popular choice to have this on board, as space in the factory is valuable.

D. Storage

Fish products must be stabilised and stored on board before unloading on land. The most common practice is to freeze the fish, but there are oceangoing trawlers with capabilities to store the fish fresh on ice. Both the freezing equipment and the cargo hold are classified under the storage system in our case.

Since around 1985, fork-lift trucks have been used inside the cargo hold to move and stow the frozen blocks that have automatically been placed on pallets. This is more time efficient and removes the need for crew to manually lift iced fish or frozen blocks into place. It also drastically reduces the unloading time – where before it was common to see dozens of people employed to unload the vessel, this is now done with a crane on deck or from a hatch in the ship side. One respondent reflected on the unloading of a vessel:

So the blocks were stowed manually and it was heavy, very heavy. Also when you had to unload, then you had – that was something. How many were [employed at the dock] to unload the boats and got paid, the football team and everything, and then it's minus 30, then it's a tough job. … Now it's on pallets, coming up automatically to be put on the dock by crane. … So here the heavy lifting was taken away.

(Semi-)automatic plate freezers are common today on vessels that deliver headed and gutted fish. Fish is manually loaded from the top and frozen in blocks. Afterwards, a plate on the bottom of the freezer is retracted and blocks are released automatically. ⁴² This saves further on crew requirement and the amount of manual labour.

Also in the development of refrigeration systems, the focus has been on energy saving. One example is automatic lowering of the system pressure when sailing in cold water. It was mentioned by one of the respondents that this can save up to 16% of power consumption when the ship is in the Arctic.

Traditionally, trawlers have used Freon R-22 as a refrigerant. Since 2015, the European Union has phased out R-22 and newbuilt ships must move to natural refrigerants. Today, almost all of the bottom trawler fleet uses ammonia as a refrigerant, which is more energy efficient, safer for the crew on board and less damaging for the environment in the case of a leak, when compared with the ‘traditional’ synthetic refrigerants.

E. The hull

The hull of the vessel is the structure that encompasses all the other systems. As the vessel has generally grown in size, the hull weight has also increased. In the design of the hull, a trade-off must always be made between (cargo) capacity and sailing resistance.

In line with the trend of fish populations moving north and a larger share of shrimp fishing, the hull of most vessels is strengthened to be able to operate in ice. This adds some more steel weight but is said to not have a huge effect on the overall design.

Also, seagoing capabilities have generally become better in the past decades, as ship design has become more data driven. It was noted by one of the respondents that this is valuable for the factory equipment, where more automated processes benefit from a calmer motion profile.

Driven by the need for a larger trawl deck, more deck equipment and relatively more space for the crew, trawlers built after around 2010 feature an extra deck compared with earlier generations. In the bow this is especially apparent, where the addition of a shelter deck allows for more crew spaces in this part.

An example of two generations of the same vessel is shown in Figure 5. ⁴³ Another interesting observation can be made that while the lengths of the vessels are similar, the newer vessel is significantly wider. This can be explained by the growing size and number of trawl winches – that are quite heavy – impacting the stability of the vessel. Increasing the width is a good way to deal with this, as well as providing for more space in the factory and cargo hold.

Figure 5.

Two generations of the same vessel. Left: the design of 1987, dimensions 65.5 by 13.0 m. Right: the design of 2013, dimensions 69.9 by 15.4 m.

F. Propulsion and machinery

The propulsion and machinery system is that which moves the vessel forward and generates and stores energy on board. A general trend is electrification of the machinery, as with the deck equipment. This makes it generally easier to integrate (new) systems and allows for better optimisation of the power system. It has become more common for vessels to have diesel–electric propulsion. Electricity is generated using a shaft generator on the main engine, supplemented by diesel generators. The propeller is driven by electric motors. The added benefit of this system is that recovered electricity, for example from winches, can be used to drive the propeller.

There are some vessels that have installed batteries on board, to be used for peak shaving. This entails taking large load differences, for example when shooting and adjusting the trawl, with batteries instead of the main engine.

Rest heat recovery systems are more or less universal today, where heat from the engine is used to drive the fish meal plant and heat the superstructure.

Driven by the increasing focus on carbon-neutral transport, the fishing vessels are also looking for alternative fuels. There have been pilots with alternative fuels in recent years, for example natural gas. Other options being considered are hydrogen and ammonia, but today there is nothing other than diesel in use on oceangoing bottom trawlers. Considering the high power requirement and a long time out at sea of these vessels, the lower energy density of alternative fuels is the largest challenge.

G. Accommodation

The accommodation considers all crew spaces such as cabins, lounges, and stores. Driven by competition for crew with the offshore sector, crew comfort on fishing vessels has increased greatly. It is common to see private cabins, with a private bathroom, television, and internet. Other things contribute to welfare, such as a more advanced gymnasium and in some cases a sauna and jacuzzi on board. The implication of this is that the accommodation relatively takes more space than before, which has influenced the addition of a deck.

Another possible implication of better cabins that one of the respondents brought up is that crew spend less time in the mess room communicating with others on board. This could lead to more unsafe situations, as there is less social control. However, no studies that specifically investigate this effect have been found.

H. Bridge

The bridge system considers mostly the flow of information on board, as well as being responsible for navigation and communication with the outside world. A large development is the amount of information the captain has available, from how much energy is being used where to how the trawl is moving through the water. This is also true for the positioning of the vessel, with the use of GPS and more advanced radar systems. Figure 6 ⁴⁴ shows an example of the large changes that have taken place on the bridge. The additional screens and centralised controls have changed the bridge into being a ‘control room’ from which most vessel functions can be monitored and controlled.

Figure 6.

Left the bridge of Helnes (1970), and right the bridge of Sørkapp (2023).

Most respondents mentioned that they are currently using services employing big data in fish finding, which assist the captain with a probabilistic model of fish distribution. Additionally, there are currently early trials with autonomous vehicles locating fish schools. Both these technologies exist with the aim of reducing the transit time of the vessel, and thus saving further on fuel use.

Before the introduction of mobile phones, all personal communication between captains at sea went over the VHF radio, to which everyone could listen in. Nowadays it is easier to contact a specific person, which one respondent hypothesised could mean that the type of information that is shared is different than before. This was not further investigated though.

I. Other

The miscellaneous category contains all other parts of the ship, for example the ship's tanks and voids (empty spaces). It also includes equipment such as ballast pumps. We have not found any changes in these other systems that are worth further commenting on; however, they should be mentioned for completeness.

Analysis

In this section, we present the drivers and barriers to technological innovation that were found from the empirical data. The different types of drivers and barriers are commented on separately for an overview, but it should be noted that all factors are related to each other, making it impossible to look at the effect of a single factor in isolation. To give one example, changing market prices will affect the profitability on the bottom line, which further impacts the investment ability of the company. The relationships between these factors are also diffuse and change over time, making it even more challenging to analyse their effects.

Drivers

Economic

The driver most often mentioned in the interviews is the market price of products. This dictates the decision of which products to produce on board, and thus what kind of equipment is invested in. An example of this are fish meal and oil, for which the market price has significantly increased in the last decade. This has driven more ship owners to install a fish meal plant on board and suppliers of this to think about the design of the plant.

Another important driver is operational profitability on the bottom line. That is, increasing revenue and reducing costs, as one respondent summarised:

So it is that which is the future now – it's really about fighting this here by keeping the price down and then keeping the quality up, and then you have to automate more and more. Reducing labour costs and thus operating expenses on the boats that is, of course.

We can infer from this that an important way to increase revenue is to increase the quality of the products, something that was mentioned by more of the respondents. A recent focus has been the gentle handling of the fish in the factory, which has resulted for example in the development of live storage tanks and the adoption of the electric stunner.

On the other hand, reducing costs works positively for profitability. A large operational cost is fuel, which is why developments in both hull design and trawl gear are driven by reducing the resistance. Another factor is reducing crew costs, which drives the development of more automated solutions in the factory.

Technological

Cross-industry innovation, to take technology from one sector to another, is a clear driver for change. The most straightforward example for fishing vessels is the development of electrical winches, which started in the offshore sector. As many of the ship designers and suppliers do business in multiple sectors, it is natural – and important – to exchange technology between these, as one respondent explained:

What we learn from the offshore – or from seaborne and pax – we bring into fishery, and what we learn in fishery we bring to the offshore. So, this is a flow of information that we have, and especially now in this kind of fuel transition we are in now we can see that this is really valuable. We have no chance to only do this for fishery. We have to use our segments to actually, what we learn, we can implement.

Pilot projects can also be considered a technological driver, in the sense of increasing the technological maturity of novel solutions. These kinds of projects assist the diffusion of technology, by acting as a bridge between research and the industry. One respondent specifically brought up the point that new technology must be proven at sea before it is accepted into industry.

Institutional

A unique aspect of the fishing industry in Norway is that the vessels are generally family-owned. The owner is often the captain, which means there is a lot of first-hand knowledge of operations and performance. This also counts for the rest of the crew, which are considered highly technically knowledgeable. The crew are generally involved in the design process of a new vessel, as one respondent explained:

And they have their things in mind, very often it's the captain that has been the strong one in these discussions sitting around the table, making new designs. Because he remembers: ‘one time we needed 100 per cent of power, so next time I need a bit more just to be sure.’ That was the tendencies we saw. When we do have facts, we can show over many years how they actually operate the vessel – we can tell the consequences of going with such a big engine or a big propeller. … But they have their operational know-how of course, [so] this is a discussion over the table, we never dictate the owner in any way.

Multiple respondents said that involving the crew in the design process opens up new ideas but might make the vessel more expensive as the crew come with more demands. In general, though, consensus is reached that it is beneficial to involve the crew in the long run. This unique organisation of the industry can thus be seen as a driver for innovation.

Many of the respondents commented on the high willingness to exchange information in the bottom trawler fleet. Knowledge sharing is a clear driver to innovation, facilitating collaboration and the development of new ideas. Short communication lines are common in this fleet segment, even between those who on paper are competitors. Multiple respondents note that this is probably unique to the fishing industry and that the reason may be that fishing is limited by quota, thus there is no competitive advantage by keeping information hidden. One respondent captured the mentality well, noting:

There is no reason to keep information away, because my competitor, if we can call them that, the only thing we compete about is people and quotas. The rest is more or less set. So, if my neighbour can have success that is good for – it's not negative for me. … If everybody can increase the quality and in that way increase the price [that we receive for our products], that's positive for us all.

Interestingly, the willingness to share data is opposite to what Sønvisen et al. concludes for the coastal, pelagic and longline fleet, where there is a widespread reluctance to do so. ⁴⁵ There appears to be a fundamental difference between the fleet groups in this regard, although this was not further examined in the current study.

Regulation is also driving the development of new solutions. A good example is the move from synthetic to natural refrigerants. In the early 2000s, the EU started to phase out R-22 on ships, which had been the standard refrigerant on the trawlers. One of the respondents explained how shipowners moved to ammonia:

It was because of the regulation that changed, everybody wanted to continue with Freon if they could. They were more or less forced into ammonia systems and now after they have had it, they are very happy with it. … a lot of refrigerants need to be phased out every year. So it's not a long-term investment, to put on such refrigerants.

It speaks for itself that if support for these substances and maintenance on the systems stops, it is no longer a good investment long term to invest in these, and ship owners will move to systems that are supported instead. Multiple respondents noted that accidents and crew safety are the main source of many regulations that have shaped the development of the vessel.

Barriers

Economic

Investment costs are a significant barrier to adopting new technology. There are plenty of examples of innovations that are technologically proven, for instance through pilot projects, but are not adopted because of the high investment price. One example brought up in the interviews is the semi-pelagic trawl doors that automatically adjust their height above the bottom. The tests done with them were successful; however, the increased costs made it impossible to invest in them.

Generally, higher prices cause a longer renewal time of the vessels. This leads to a longer time between innovation processes, which means that over time there is less possibility for adopting new technological solutions.

The possibility of processing products abroad, generally in low-wage countries, might also be a barrier to technological innovation. When it is cheaper – or in other ways attractive – to move production processes abroad, there is no incentive to improve these processes. During the interviews it was mentioned that people are concerned about this current practice. However, there is consensus that the processing factories abroad give a high utilisation of the raw material. This combined with a lower cost as opposed to processing on board has also had a hand in the reduction of the number of factory trawlers in Norway.

Technological

Technological complexity and difficulties with integrating new solutions into the vessel and operations were also mentioned during the interviews. Voiced as the principle keep it simple stupid, some of the respondents note that some solutions may be too innovative to actually work at sea. A point related to this is the ability to fix things on board while fishing, as one respondent noted:

Then I’m a bit like that, keep it simple, to think in that way. … Because you are a long way away from all sorts of special expertise that you might need for things.

In that sense, complexity is a clear barrier to adopting innovation. For example, if a new machine requires a fundamentally different way of operating, it might be challenging for the crew to adapt to that. This means that, naturally, there is a resistance to overcome before the innovation is adopted into industry.

Institutional

While we identified that regulation can be a driver for innovation, it is also a clear barrier. The government is generally seen as slow to adapt to technological change, which is expressed by some respondents as feeling they are ‘stuck to the regulations’. They wish to implement or explore new solutions but feel that governmental support is lacking to actually do so. As one respondent put it:

But for some, like the purse seiners and longliners, they are trying new equipment to catch the fish. … And that's something the stern trawlers also try to implement, and – but they are stuck to the rules and regulations that they need to catch [the fish] in a certain way. And that can be a problem.

This lack of flexibility in the regulations results in a clearer example of path dependence. Another example is whether or not to produce fillets on board, something that is highly regulated and has therefore not seen major developments in recent times.

As mentioned before, most fishing companies are family owned. This also entails that most only operate a single vessel: all of the company's money is in a single vessel, which poses a certain financial risk. It is expressed by some of the respondents that ship owners in the fishery are generally risk-averse when contracting a new vessel. They want something that they know will work, as the whole business revolves around the single vessel. This also works into the point that some respondents make regarding the second-hand value of the vessel. Already in the design phase, it is known that the vessel will be sold at some point, thus installing ‘too new’ technology might make it harder to sell the vessel on the second-hand market.

From the empirical data it became clear that there is a certain loyalty that ship owners have towards suppliers and ship designers. One respondent explained that the design process of a new fishing vessel is like business-to-customer, as opposed to other vessel types where it is more like business-to-business. This means that the process is based on the contacts that the ship owner has, and that the ship owner is closely involved in the details of the design. Combined with the high amount of technical knowledge of the ship owner, this results in the tendency to choose a supplier that they have received a vessel from before. This could influence the vessel and its equipment being ‘locked to the path’ of the particular supplier, as they use their experience for the new solution.

Conclusions and outlook

This article has shed a light on the historical development of the Norwegian oceangoing bottom trawler and has investigated the drivers and barriers behind the technological innovation on board, supported by empirical evidence collected from 12 semi-structured interviews with senior representatives of firms in the trawling industry. Our conclusions on the research questions follow:

1. How has Norwegian oceangoing trawler design developed since the 1960s?

While the concept of the oceangoing trawler is still exactly the same as it was in the 1960s, there have been numerous incremental developments in nearly all systems on board. We can conclude that all these developments are examples of sustaining innovations, as they either improved an existing solution or did not gain significant market share. Certainly influenced by path dependence, the systems on board the new vessels are not fundamentally different from their older counterparts. That is not to say that the vessels have not become better, they have for example improved in terms of fuel efficiency. ⁴⁶ It should, however, be repeated that ‘becoming better’ is subjective, as mentioned earlier.

2. Which drivers and barriers have influenced technological innovation in the fleet?

We found a multitude of economic, technological, and institutional drivers and barriers to technological innovation. The split into these distinct types of drivers and barriers made it possible to comment on each one separately. It should, however, be noted again that all factors influence each other and that it is impossible to quantify the effect of each separately. An overview of the factors that were found is shown in Table 1.

Table 1.

Overview of drivers and barriers of technological innovation identified in our study.

	Economic	Technological	Institutional
Drivers	Product market price	Cross-industry innovation	Organisation of industry
	Operational profitability	Pilot projects	Willingness to exchange data
			Regulation
Barriers	Investment costs	Technological complexity	Regulation
	Renewal time of vessels		Risk-aversion of ship owners
	Processing abroad		Business loyalty

We conclude that the Norwegian oceangoing bottom trawler has a complex history and an interesting position in the fishing fleet. Path-dependent processes and the framework conditions that the industry is exposed to mean that, overall, there has been a lack of disruptive innovation on this vessel type. The influence of economic and political factors, as expressed through the concept of sociotechnology, has clearly shaped the historical development of the bottom trawler design. The institutions that exist in the trawling industry – for example, formed by the relationships between ship owners, ship designers, and equipment suppliers – have established conventions in the design process that, in turn, have led to struggles when developing new technological solutions.

While we identified our sample to be able to cover the broad range of opinions and knowledge in the trawling industry, we do not claim our analysis to be exhaustive; there might be more factors that have influenced technological innovation or will do so in the future. Therefore, we can say that the results are more suggestive than conclusive. Still, we believe that the perspectives given in the current article are interesting for future work. To give one example, a similar analysis of other countries’ fleets could be performed to see if the factors that emerge correspond to those found in this article.

Finally, we give an outlook on the future. From the interviews, we found that the largest technological challenge that the industry stands for today is the energy source for the future. There have been trials with alternative fuels, such as natural gas, hydrogen, or methanol, but none of these fuel technologies have been installed on a bottom trawler as of today. There is not yet an alternative fuel that is technologically mature, has a sufficient supply chain and can compete with the energy density of marine diesel oil at the energy demand of the bottom trawler.

An opportunity that arises connected to the energy challenge is employing nuclear energy on board, something that was also pointed out by multiple respondents. This has the potential to be an emission-free alternative to the current status quo. The energy demand of the oceangoing trawler matches current generators being researched for marine propulsion. However, there are a lot of challenges to be addressed: from technical issues such as ramping (accommodating a changing power demand in a short time) to navigating the regulatory landscape. Furthermore, the fact is that none of the new reactor technologies have ever been used at sea. Thus, it is key that collaboration between research and industry is fostered in order to test the technology in a real environment. ⁴⁷

Another challenge for the industry is the institutional uncertainty of governance and quota management. After some record-high years, the cod quota in 2025 is down to the level of before 1994, ⁴⁸ and it is not expected that this will rise again soon. This challenge is further reinforced by the lack of flexibility that current trawler designs have, as one respondent noted:

We have very little flexibility. We would like to have more of that, and I think that from an environmental perspective that would also be beneficial.

What is meant here is that flexibility in the distribution of quota within a fishing company could reduce the transit time of the vessels that are in different fisheries at the same time, thus saving on overall emissions from the fishing fleet.

Respondents also see potential in an even smarter way of operating the trawler. The rise of artificial intelligence opens for wider use of data-driven methods. It is, for example, possible to install a camera at the opening of the trawl and monitor the catch in real time, transforming a blind process into an informed process. ⁴⁹ This is also possible to do when the fish come on board, where the use of computer vision can monitor and quantify discards. ⁵⁰ These options, making the catch process more transparent, could support a more flexible regulatory framework, which could in turn promote innovation. However, the usual barriers to innovation also apply here.

A significant recent development is the delivery of the factory trawler ECOFIVE in early 2025. ⁵¹ The vessel sports a radical innovation: the catch is not brought on board via the stern ramp but is rather directed into live storage tanks through an opening below the waterline. The idea is that the catch does not leave the water and is not exposed to pressure damage as when hauling over the stern ramp, which should increase the quality of the product. ⁵² This is a recent example of a disruptive technology being introduced to the oceangoing trawler, something that is noteworthy in itself. Additionally, the factory is equipped for producing fillets on board, which further breaks with recent tradition. Perhaps unsurprisingly, there has been widespread scepticism throughout the industry of whether this concept will work. One respondent noted:

It will be exciting to see how the future trawlers [for example ECOFIVE] will practically work at sea. It can be too innovative also. And keep it simple is often the best, that is what I am thinking anyway.

Still, we estimate that it is likely that if the new vessel works and is proven at sea, others will jump on the idea, as another respondent noted:

As always, as human beings we are risk averse. So all changes are met with scepticism. … But always, they will wait for a while and see if it works or not. If it's a success, everyone will probably jump on it.

This mentality is, of course, not new – as we illustrated with the example of Longva and following factory vessels, it is common for new solutions to be met with scepticism. Time will tell if the same will happen again, and if we will see a new rise of factory trawlers or not.

All in all, we conclude that if the wish is to prepare for disruptive innovation on the oceangoing bottom trawler – breaking the path-dependent chain – there must be a completely new way of thinking from the start of the design process.

Supplemental Material

sj-docx-1-ijh-10.1177_08438714261452793 - Supplemental material for Drivers and barriers of technological innovation in the Norwegian bottom trawler fleet, 1960s–2025

Supplemental material, sj-docx-1-ijh-10.1177_08438714261452793 for Drivers and barriers of technological innovation in the Norwegian bottom trawler fleet, 1960s–2025 by Jesper van Der Meij, Julia V. Bondeli, Lars Erik Nygård, Stian Skjong and Karl Henning Halse in International Journal of Maritime History