The rise and fall of factory trawlers: An eclectic approach

Factory trawlers are the most controversial vessel group in Norwegian fisheries. At the time the fleet emerged, stern trawling in combination with on-board processing of cod fillets was regarded as a major innovation. However, the deep-sea fleet was intended to be a stable supplier of fish to the land-based industry. Factory trawlers were not a part of the political project. On the contrary, the vessels represented a serious departure from the traditional employment system for the fisheries’ dependent districts. Factory trawlers have, since the seventies, been regarded as the main enemy to the coastal vessels and the land-based industry. The vessels have been subject to a profound debate about several built-in contradictory goals for the fisheries policy, such as the ideal of employment for all and the need for a profitable sector without state subsidies. Despite a series of policy-driven initiatives to remove the factory trawlers, the fleet has been one of the most profitable vessel groups in the Norwegian fisheries. Nonetheless, the fleet is now marginalised in the number of vessels and transformed into an obedient supplier of round fish to the land-based industry. In this article, we outline the history of the Norwegian factory trawlers and how the fleet was subject to a series of critical changes reflecting the complexity of the vessels.     

The IVQ regime in Norway: A stable alternative to an ITQ regime?

Since the introduction of quotas and licences as important management tools, Norway has insisted on an individual vessel quota regime (IVQ). The main argument has been to avoid market-based transactions of quotas and vessels and secure stability in regard to a diverse fleet structure and decentralized ownership of scarce cod resources. Thus, an individual transferable quota system (ITQ) with a high degree of transactions and the potential for a heavy concentration of quota ownership and fewer vessels has never been an alternative. However, since the late 80s, the trawler fleet has been trapped within a web of unprofitable overcapacity. Within the frame of a closed management regime and a path-dependent IVQ system, the quota regime has been forced towards a market-orientated system for transactions. In this article, we analyze the Norwegian IVQ system and discuss whether the aggregate effects of the IVQ regime are congruent with the models’ profound ideals.     

Juvenile albacore from New Zealand (note)

Juvenile albacore (Thunnus alalunga) caught in the New Zealand region between 1970 and 1972 are about 1 year old. There is some evidence of southward migration of these small fish along the west coast. Small albacore also occur in the North Pacific.     

Observations of Hector's dolphins (Cephalorhynchus hectori) associating with inshore fishing trawlers at Banks Peninsula,New Zealand

Fishing activities have the potential to alter the behaviour of cetaceans and pose a threat through bycatch. We present observations concerning the influence of inshore trawling on group size and behaviour of Hector's dolphins (Cephalorhynchus hectori) at Banks Peninsula, New Zealand, made during photo‐ID surveys from 2003 to 2007. Aggregations of dolphins, typically involved in what we assumed to be foraging behaviour, were observed following small inshore trawlers year‐round. Group size was larger for aggregations of dolphins following trawlers (mean ± SE = 22.9 ± 1.3, n = 83) than for non‐trawler groups (3.7 ± 0.2, n = 439), and dolphins were typically in a more “excited” state, frequently exhibiting aerial and sexual behaviours. We suggest that trawlers increase the availability of prey for Hector's dolphins and hence foraging behind trawlers is an energetically favourable activity. However, following trawlers probably also increases the risk of being caught in trawl nets, compounding the threats faced by this endangered species.     

三亚蜈支洲岛毗邻海域鱼类物种多样性及群落结构特征

准确掌握鱼类物种多样性及其资源时空分布规律是鱼类资源养护和利用的基本前提和重要基础。作者采用底拖网在蜈支洲岛毗邻海域进行年际(2020年8月和11月、2021年1月和4月)的渔业资源调查,共捕获鱼类174种,隶属2纲、12目、65科、123属,趋礁性鱼类物种数有较高的比重(35.6%)。常年种(宽条鹦天竺鲷(Ostorhiegnchus fasciatus)、准大头狗母鱼(Trachiocephalus myops)和少鳞䲢(Uranoscopus oligolepis))为主导该海域鱼类资源量季度变化的主要类群,但季节种(印度侧带小公鱼(Stolephorusindicus)、短鳄齿鱼(Champsodonsnyderi)和鹿斑仰口鲾(Secutor ruconius)等)也能在一定程度扰动由常年种鱼类主导的鱼类群落结构,从而使得群落结构呈季节性变化。除秋季外,其他3个季节的鱼类群落组成主要为幼鱼,表明毗邻海域的岛礁生境有聚集鱼类和保育幼鱼的重要作用。与该海域2019年的渔业资源调查数据比较,其鱼类组成丰富度与均匀度高度一致,鱼类群落未发生生态位交替失调现象,表明蜈支洲岛毗邻海域鱼类群落结构较为稳定且资源状况良好。本研究所获得的相关数据将有助于蜈支洲岛海洋牧场建设过程中的生态效果评估的工作开展。     

Impacts of a bottom trawling exclusion zone on Snow Crab abundance and fish harvester behavior in the Labrador Sea, Canada

The Hawke Box trawling exclusion zone off southern Labrador is a 8610 km² closed area implemented in 2003 to protect soft-shelled pre-recruit Snow Crab and juvenile cod from mortality imposed by shrimp trawling and other bottom-impact fisheries. This study utilizes survey, logbook, and observer data from the Snow Crab and Northern Shrimp fisheries to assess the effectiveness of the Hawke Box in protecting and possibly enhancing the Snow Crab resource off southern Labrador. The results indicate that the exclusion zone has failed to protect pre-recruit crabs largely due to a redistribution and intensification of directed Snow Crab effort inside the Box in the years following closure. This unexpected outcome resulted in a high level of fishery-induced mortality to pre-recruit crabs and masked any potential positive outcomes from the cessation of trawling. The shortcomings that contributed to the failure of this exclusion area are discussed in relation to the current state of knowledge on the effectiveness of marine protected areas in general as management tools for conserving aquatic resources.     

A Baseline Study on Benthic Species Distribution in Two Neighbouring Gulfs, With and Without Access to Bottom Trawling

Abstract. An extensive survey of the benthic fauna was carried out at two neighbouring regions of the Aegean Sea, one normally trawled and the other closed to trawlers. Benthic samples were collected from seven areas located away from land-based sources. The faunistic analysis showed that species diversity and abundance was higher in the trawled area compared with the untrawled area, a fact which was attributed to the difference in sediment characteristics between the two areas. A degree of disturbance detected in the trawled area was evidenced by an increase in the number of polychaetes at the expense of other benthic groups and an abundance of some opportunistic species. This could possibly be related to trawling activities. as no other causes of disturbance were found in either area.     

Spatial heterogeneity and long-term changes in bivalveAnadara broughtoni population: influence of river run-off and fishery

A comparison was made of population of the economically important cockleAnadara (=Scapharca)broughtoni (Bivalvia, Arcidae) inhabiting different areas of the Razdolnaya River estuary at the head of Amurskii Bay (Peter the Great Gulf, East Sea). Also, changes in cockle population density and structure, as well as in cockle growth rates during the last 20 years were studied. In all years of investigation, the morphometrical parameters and growth rates of cockles were smaller at the sites located close to the River mouth than farther down-estuary. The differences can be attributed to higher concentration of suspended particulate matter, decreased salinity and water temperature, as well as a longer exposure to these unfavorable environmental factors at sites located close to the River mouth, compared to farther sites. For two decades, cockle population density had decreased by almost 30 times at some sites in the River estuary. The main reason for this population decline is commercial over-fishing of the cockle. Besides, for the last 20 years, linear parameters of the cockles in the population decreased approximately by 30% and weight parameters, almost two times. Cockle growth rates also decreased for this period. Evidently, these facts are due to the damaging effect of dredging.