Seal interactions and exits from fisheries: insights from the Baltic Sea cod fishery

Johan Blomquist,Staffan Waldo,Yinji Li

doi:10.1093/icesjms/fsab173

Johan Blomquist, Staffan Waldo + Show 1 more

Open Access

https://doi.org/10.1093/icesjms/fsab173

Copy DOI

Abstract

AbstractThe number of seals in the Baltic Sea has increased dramatically in recent years. While growing seal populations are associated with a thriving marine environment, seals interact with coastal fisheries causing significant damages to catches and gears. One fishery that is severely affected is the coastal cod fishery where the negative impact of seals is believed by many to threaten the existence of the fishery. This article empirically investigates to what extent seal damages can explain the declining number of fishing vessels active in the Baltic Sea coastal cod fishery. The analysis makes use of detailed logbook data and statistical survival models to estimate the effect of seal interactions with fishing gears on the exit probability of vessels in the Swedish cod fishery. The results show that seal interactions is an important factor explaining exits, suggesting that total losses caused by seals go beyond observed costs of broken gears and damaged catches.

Highlights

In the last decades, the Baltic Sea seal populations have increased rapidly
Using logbook data between the years 2006 and 2016 the aim of this study is to examine whether seal interactions with fishing gears increase the probability of vessels exiting the cod fishery
Seal interactions with gears constitute an important factor why vessels exit the coastal cod fishery, especially when interactions increase from an already high level

Summary

Introduction

The Baltic Sea seal populations have increased rapidly. For example, the grey seal (Halichoerus grypus) population has more than doubled since the early 2000s, from around 25 000 seals in year 2003 to around 60 000 in 2019 (SwAM, 2019). Seals are known to cause problems for coastal fisheries by interacting with fishing gears, leading to lost catches and damaged gears. Such losses, referred to as “seal damages” in this paper, negatively affect the economic viability of fishing. In interview studies and surveys with coastal fishermen operating in the Baltic Sea, the problem of seal damages is regularly referred to as one of the most important factors why they consider leaving the sector, especially in Sweden and Finland Increasing seal damages may be seen as at odds with the Swedish management objective that the impact of seal populations on human interest should be natural or positive (SwAM, 2019). The coastal fisheries are regarded important for the cultural heritage and for preserving regional employment in many coastal communities (Bjorkvik et al, 2020), and the declining number of fishermen has made community representatives and local residents deeply concerned (Wernersson et al, 2017; Johansson and Waldo, 2021)

Objectives

Methods

Results

Conclusion