Year | Landings (t) | No. samples | No. length measured |
---|---|---|---|
2000 | 31393 | 167 | 34357 |
2001 | 17230 | 95 | 18563 |
2002 | 19045 | 177 | 32500 |
2003 | 28478 | 149 | 26196 |
2004 | 17564 | 117 | 19640 |
2005 | 20563 | 596 | 93465 |
2006 | 17208 | 325 | 50237 |
2007 | 17372 | 203 | 30107 |
2008 | 24125 | 192 | 32535 |
2009 | 19429 | 168 | 27647 |
2010 | 17642 | 168 | 28464 |
2011 | 11737 | 138 | 21239 |
2012 | 11963 | 69 | 11237 |
2013 | 8761 | 63 | 9360 |
2014 | 9501 | 93 | 15380 |
2015 | 9314 | 58 | 9089 |
2016 | 9537 | 88 | 13026 |
2017 | 8372 | 45 | 8570 |
2018 | 9996 | 27 | 5038 |
2019 | 8715 | 40 | 7509 |
2020 | 11375 | 29 | 5508 |
2021 | 10589 | 26 | 4125 |
2022 | 9465 | 8 | 319 |
2023 | 6675 | 22 | 2045 |
2024 | 2704 | 26 | 3018 |
Key signals
- The total biomass and abundance indices have fluctuated about a constant level since 2003.
- Survey estimates have consistently shown very low abundance of pre-fishery juveniles (< 30 cm) since 2012.
- Length distributions from surveys and fisheries show a progressive shift toward larger fish over time, reflecting an aging population and a long period (2012–present) with very low recruitment.
- Spawning stock biomass (SSB) declined from 1990–2000, was relatively stable from 2000–2016, and has since declined to lowest level.
- Fishing mortality (F) has declined since the mid 1990s and dropped below FMSY in 2024.
General information
Icelandic slope beaked redfish (Sebastes mentella) is a deep-water redfish species, similar in appearance to golden redfish (S. norvegicus) but distinguishable by certain characteristics, notably its deeper habitat (>400 m). Around Iceland, it is primarily found in the warmer waters along the western, southern, and south-eastern continental slope. Like other redfish species, beaked redfish is slow-growing, long-lived, and matures late.
This species is considered a separate biological stock and management unit within the Icelandic waters ecoregion, which encompasses ICES Division 5.a and part of Subarea 14 within the Icelandic 200 NM EEZ. In Icelandic waters, individuals larger than 30 cm are predominantly observed. The East Greenland shelf is believed to serve as the main nursery area for this stock.
Information from the fishing industry
Landings
Total annual landings of Icelandic slope beaked redfish from the Icelandic Waters Ecoregion during 1950–2024 are shown in Figure 1.
From 1950 to 1977, prior to the extension of Iceland’s EEZ to 200 NM, the fishery was primarily conducted by West Germany. Catches peaked in 1953 at around 87 000 t, then gradually declined to approximately 23 000 t by 1977. Following the EEZ extension in 1978, the fishery has been almost exclusively prosecuted by Icelandic vessels.
Landings declined steadily from 57 000 t in 1994 to 17 000 t in 2001 and remained at similar levels until 2010. Between 2011 and 2024, annual landings ranged from 2 500 to 12 000 t. In 2024, the total catch was 2,618 t — a decrease of 4,057 t from the previous year.
Fisheries and fleets
The fishery for Icelandic slope beaked redfish in Icelandic waters is a directed bottom trawl fishery conducted along the continental shelf and slope southwest and west of Iceland, typically at depths between 500 and 800 m (Figure 2). The number of vessels accounting for 95% of the total catch has declined steadily over time (Figure 3).
Sampling from the commercial fishery
Table 1 shows biological sampling from the catch of Icelandic slope beaked redfish in the Icelandic Waters Ecoregion during 2000–2024. Both the number of samples and the number of length measurements have declined since 2012.
Figure 4 displays the number of samples collected by month from 2012–2024, clearly illustrating the reduction in sampling over time. This decline is primarily due to reduced sampling effort by onboard observers from the Directorate of Fisheries.
The spatial distribution of sampling relative to the fishery during 2020–2024 is shown in Figure 5 and indicates that most sampling effort occurs where the fishery is concentrated.
Length distribution from the commercial catch
Length distributions of Icelandic slope beaked redfish from the bottom trawl fishery show a noticeable increase in the number of small fish in the catch in 1994 compared to previous years (Figure 6). A distinct peak near 32 cm in 1994 can be traced through subsequent years, showing approximately 1 cm of annual growth from 1996 to 2002.
From 2004 to 2024, the length distribution has typically peaked around 39–43 cm. In contrast, where data are available, the length distribution from the pelagic fishery shows that the fish caught were generally larger on average than those taken in the bottom trawl fishery (Figure 6).
Catch per unit effort
Trends in non-standardized CPUE (kg/hour) and fishing effort (thousand hours fished) are shown in Figure 7. The CPUE from tows in which more than 50% and 80% of the catch consisted of Icelandic slope beaked redfish declined steadily from 1978 to a record low in 1994. Since then, CPUE has increased consistently, reaching the highest levels in the time series in 2020 and 2021.
Between 1991 and 1994, the decline in CPUE coincided with a substantial increase in fishing effort. Effort has since declined and is now comparable to levels observed in 1980. CPUE and effort data are not available for 2022.
Discard
Although no direct measurements are available, discarding of Icelandic slope beaked redish is believed to be negligible.
Scientific data
The Icelandic autumn survey (IS-SMH), conducted on the continental shelf and slope in Icelandic waters, covers depths down to 1 500 m. Data on Icelandic slope beaked redfish are available for the period 2000–2024, except for 2011 when the survey was not conducted.
Survey indices
The total biomass and abundance indices were highest in 2000 and 2001, declined in 2002, and have since fluctuated around that level without a clear trend (Figure 8).
The biomass index of fish ≥45 cm increased from its lowest point in 2007 to a peak in 2021 but has declined since then (Figure 8). In contrast, the abundance index of fish ≤30 cm (recruits) has remained very low since 2010. No fish smaller than 30 cm were observed in the 2021 and 2022 surveys, and only very few were observed in 2023 and 2024 (Figure 8).
Distribution
Icelandic slope beaked redfish in the Icelandic autumn survey is caught along the continental slope from the south-east to the west of Iceland (Figure 9), with highest abundances observed southwest along the Reykjanes Ridge and west of Iceland (Figure 10). The species is primarily caught at depths between 400 and 800 m (Figure 11).
Length and age
The length of Icelandic slope beaked redfish observed in the autumn survey ranges from 25 to 55 cm (Figure 12). Since 2000, the mode of the length distribution has shifted to the right — from 36–39 cm in 2000 to approximately 42–45 cm during 2012–2024. Over the same period, the mean length of sampled fish increased from 37.4 cm in 2000 to 43.2 cm in 2024.
This is a substantial increase in mean length, particularly given that the species grows slowly (approximately 1–2 cm per year) and that individuals over 50 cm are rarely observed. The absence of smaller size classes and this shift in size structure are consistent with a recruitment failure.
Otoliths from the autumn survey have been collected since 2000, with age readings completed for 10 survey years (Figure 13). The results show that the stock is composed of many cohorts, with ages ranging from 5 to over 50 years. The 1985 and 1990 cohorts were particularly strong and remained relatively abundant in the 2021 survey.
Signs of recruitment failure are evident in the age distributions, with very few individuals aged 10 years or younger observed since 2018.