NORTHERN SHRIMP IN THE SNÆFELLSNES AREA

Pandalus borealis


Assessment report
Published by

Marine and Freshwater Research Institute, Iceland

Published

30 April 2025

The fishery

The fishing ground for northern shrimp in the Snæfellsnes area is defined by Kolluáll, southern part of Breiðafjörður and Jökuldjúp (Figure 1). Northern shrimp fishing in the southern part of Breiðafjörður is only allowed between 8 May and 31 July for vessels of 105 GRT or smaller, which have quota in the Snæfellsnes area.

Figure 1: Northern shrimp in Snæfellsnes area. The defined area for northern shrimp fishing in the Snæfellsnes area (K=Kolluáll, J=Jökuldjúp, S=southern part of Breiðafjörður). The broken line defines Breiðafjörður where northern shrimp fishing is allowed between 8 May and 31 July for vessels 105 GRT or smaller and with quota at the Snæfellsnes area.

Northern shrimp catch in the Snæfellsnes area was high from 1992 to 1995, when the annual catch reached almost 8000 tonnes (Figure 2). It is likely that high fishing pressure during that time led to a collapse of the northern shrimp stock. The northern shrimp catch was low from 1997 to 1999 but increased after 2007 until it reached a maximum in 2012-2014. In 2019, the catch was very low but increased again in 2020 – 2022. The number of commercial shrimp vessels in the Snæfellsnes area increased sharply until 1994 when 47 vessels landed shrimp. In 2006, few vessels landed shrimp, but the number increased again in the following years until 2015 when it decreased again and only 3 vessels landed shrimp in 2023 (Figure 2).

Figure 2: Northern shrimp in the Snæfellsnes area. Total catch and number of commercial vessels operating in the area.

Catch per unit effort (CPUE) decreased from 2000 to 2003 but increased again until 2006 when it was highest (Figure 3). It decreased until 2011 and has been relatively stable since then. CPUE was highest in March-May but decreased in the following months. Changes in CPUE are limited with increasing trawl size, except for trawl with 3500-4000 meshes.

Figure 3: Northern shrimp in Snæfellsnes area. Standardized catch per unit effort (CPUE) of northern shrimp by year, month and trawl size (number of meshes).

Generally, CPUE increases with increasing total biomass index (Figure 4). However, the variability is higher when the total biomass index is above 1000. There is a decent consistency between CPUE and the total biomass index.

Figure 4: Northern shrimp in Snæfellsnes area. On the left: Relationship between standardized catch per unit effort (CPUE) and total biomass index. To the right: Standardized CPUE (red line, left axis) and total biomass index (blue line, right axis).

The distribution of the fishery has varied over time (Figure 5). Between 1988 and 1996, the main fishing grounds were in the western part of the Snæfellsnes area (Kolluáll). Since 2006 the main fishing grounds have been closer to land, northwest of the Snæfellsnes peninsula. The fishery is mainly conducted during the summer and in 2024 the fishery only took place in May.

Figure 5: Northern shrimp in Snæfellsnes area. Spatial distribution of catch.

Survey data

The northern shrimp survey in the Snæfellsnes area has been conducted annually since 1990 (except in 2007, 2021, 2022 and 2024). Information on sampling procedure can be found in the manual for the project (Jónsdóttir 2025). The 2025 survey was conducted 22 – 26 April and included 31 fixed stations at depths of 120 – 333 m. The density was highest in Breiðafjörður (Figure 6). However, in 2017 – 2023 northern shrimp density was similar in Kolluáll and Breiðafjörður.

Figure 6: Northern shrimp in Snæfellsnes area. Distribution and abundance in the annual northern shrimp survey. X denotes stations where no northern shrimp was found. The survey was not conducted in 2007, 2021, 2022 and 2024.

Indices

Four indices are used to assess the state of the offshore northern shrimp stock: total biomass, fishable biomass, female biomass, and juvenile biomass. Juveniles include all individuals equal to and below 13 mm carapace length, while the fishable biomass includes all individuals equal to and above 15.5 mm carapace length. The fishable biomass index is used for calculation of the advice. Individuals between 13 and 15.5 mm carapace length were divided linearly between the juvenile and fishable biomass indices. The female biomass includes all females and is defined as the spawning stock biomass.

All indices fluctuated without a clear long-term trend during the study period (Figure 7). Indices decreased sharply in 1995 – 1998 during the time of high fishing pressure. In 2008 – 2016 all indices except the juvenile index fluctuated around the long-term mean. In 2017 – 2020, the indices were substantially lower compared with previous years and were the lowest observed since 2005. The total biomass index was above the reference level where the state of the stock is considered critical. The fishable index value of 20% of the mean of the three highest indices (Ilim) is used as a proxy for Blim. The juvenile index fluctuated without a clear trend from 1990 to 2013 but has been very low since 2014.

Figure 7: Northern shrimp in Snæfellsnes area. Total stock index, fishable index, female index and juvenile index (biomass indices). Ilim (dashed line) is a proxy for Blim (20% of the mean of the three highest indices). The survey was not conducted in 2007, 2021, 2022 and 2024.

Length distribution

A high proportion of the stock is mature females, whereas males compose a considerably lower proportion of the fishable biomass (Figure 8). The absence of juveniles indicates that the recruitment patterns and drift of larvae from adjacent areas are unknown. Length distribution has remained similar in 2019 – 2025.

Figure 8: Northern shrimp in Snæfellsnes area. Length distribution. Males (black line), females (red line) and the mean length distribution of both sexes for the whole study period (grey area). Denote different scales on the y-axis.

Abundance of Atlantic cod and haddock

The abundance of 1 year old haddock has been high since 2020. The abundance of 2 year and older haddock was low in 2011 – 2025 with the exception of 2023 when the abundance was very high.

No 1 year old cod were found, the abundance of cod 2 year and older was relatively high between 1993 – 2006 but decreased in 2014 – 2019 and has remained low since then.

Figure 9: Cod and haddock in Snæfellsnes area. Abundance indices in the annual offshore northern shrimp survey. The survey was not conducted in 2007, 2021, 2022 and 2024.

Temperature

Mean surface and bottom sea temperature both increased during the early part of the survey peaking in 2008 and 2003, respectively. After a decrease to 2020, sea temperature has increased again (Figure 10).

Figure 10: Temperature. Mean surface temperature (red) and bottom temperature (black) in the Snæfellsnes area during the northern shrimp survey.

Management

The Ministry of Industries is responsible for management of all marine fisheries in Iceland and implementation of legislation. The Marine and Freshwater Research Institute (MFRI) first recommended TAC for northern shrimp in the Snæfellsnes area in 2002, but until 2014 this area was included with the offshore northern shrimp fishery and hence, no TAC was issued specifically for this area. For the quota years 2010/2011 to 2013/2014, the offshore northern shrimp fishery was open to all boats without a TAC. During some of these years, fishing of northern shrimp in the Snæfellsnes area was considerably higher than the recommended TAC. In 2015, the MFRI suggested that the quota year for the area begins at 1 May and ends on 15 March the following year. Because females release the eggs in the spring, Northern shrimp fishing has been prohibited from 16 March to 30 April since 2015. TAC and landed catch has roughly followed the advice given by MFRI (Figure 11).

Figure 11: Northern shrimp in Snæfellsnes area. Comparison of the advice, landed catches and the set TAC.

References

Jónsdóttir, I.G. 2025. Handbók um stofnmælingu rækju árið 2025. Kver Hafrannsóknastofnunar, KV2025-003.