| Length(cm) | age1 | age2 | age3 | age4 | Total Number | Total Biomass (tonnes) |
|---|---|---|---|---|---|---|
| 8.5 | 1907 | 0 | 0 | 0 | 1907 | 5527 |
| 9 | 5877 | 0 | 0 | 0 | 5877 | 20271 |
| 9.5 | 11481 | 0 | 0 | 0 | 11481 | 47389 |
| 10 | 17854 | 0 | 0 | 0 | 17854 | 86157 |
| 10.5 | 19004 | 0 | 0 | 0 | 19004 | 107696 |
| 11 | 19393 | 79 | 0 | 0 | 19473 | 128578 |
| 11.5 | 18132 | 184 | 0 | 0 | 18316 | 139444 |
| 12 | 10995 | 450 | 0 | 0 | 11445 | 99659 |
| 12.5 | 7372 | 816 | 159 | 0 | 8347 | 83804 |
| 13 | 2653 | 1320 | 79 | 0 | 4053 | 46225 |
| 13.5 | 1223 | 2036 | 79 | 79 | 3419 | 44004 |
| 14 | 550 | 1768 | 79 | 0 | 2397 | 35539 |
| 14.5 | 173 | 2934 | 289 | 0 | 3396 | 57549 |
| 15 | 25 | 3215 | 172 | 0 | 3412 | 66042 |
| 15.5 | 0 | 2627 | 130 | 0 | 2757 | 61146 |
| 16 | 0 | 2302 | 279 | 0 | 2580 | 64069 |
| 16.5 | 0 | 1453 | 294 | 0 | 1746 | 49333 |
| 17 | 0 | 937 | 245 | 41 | 1223 | 37333 |
| 17.5 | 0 | 290 | 170 | 16 | 492 | 16651 |
| 18 | 0 | 41 | 179 | 0 | 220 | 8421 |
| 18.5 | 0 | 0 | 64 | 0 | 64 | 2441 |
| 19 | 0 | 0 | 25 | 0 | 25 | 1257 |
| 20 | 0 | 0 | 16 | 0 | 16 | 842 |
Executive summary
The size of the capelin stock and the catches have fluctuated between years and are reflecting the size of the incoming cohort at any given time. Since changes occurred in the stock’s nursery and feeding grounds since around 2000, both stock size and catches have generally been smaller.
The capelin spawning stock biomass was estimated to be of 417.5 thousand tonnes in the 2025 autumn survey. Taking into account the measurement, the estimated predation on the capelin stock, and the coastal states harvest control rule, the capelin catch for the 2025/2026 fishing year shall not exceed 43 766 tonnes.
The total biomass estimate in the autumn survey of 2025 was of 1 209 thousand tonnes. The index of the abundance of juvenile capelin is 118.9 billion, the 5th largest in the time series and indicating that the year class 2024 is large.
General information
The capelin is a small pelagic schooling fish. It is a cold-water species that inhabits arctic and subarctic waters in the North Atlantic and North Pacific. Capelin in the Iceland-East Greenland-Jan Mayen area (IEGJM) is considered to be a single stock, and is denoted here after as the IEGJM capelin stock.
Fisheries of capelin began in Iceland in the mid-1960s. Besides being commercially important, capelin is a key species in the marine ecosystem off Iceland. It feeds on small zooplankton, especially copepods but also amphipods and krill, but is itself an important food for cod, saithe, haddock, halibut and other commercial fish. It is also important prey for whales and birds. Thus, capelin is an important link in the transfer of energy and nutrients to the upper levels of the food web. Preferred temperature for capelin is usually 1-3°C during feeding migration and it is then often at the southern extent of cold Arctic water. When the adult capelin migrates from the feeding areas far north of Iceland, east and southeast of Greenland, it is mainly considered to approach the shelf break north of Iceland and then migrate clockwise around the island. Part of the main migration continues all the way towards the coast west of Iceland. Spawning takes place in shallow water in March-April in relatively warm seas south and southwest coast of the country. Spawning has also been observed in coastal areas north of Iceland but the extent of that spawning has been considered small compared to the number that spawns in the south. The majority of capelin dies after spawning, usually at the age of 3 years, although mostly females may survive spawning (Christiansen et al., 2008). The migrations of capelin contribute to a huge transfer of energy into the ecosystem of the Icelandic continental shelf. Larvae and juveniles drift clockwise along the continental shelf north and east of Iceland and in variable quantities towards Denmark Strait and to the shelf of East Greenland. Nursery grounds of capelin are in the waters north of Iceland and increasingly on the continental shelf of East Greenland since the early 2000s (Bardarson et al., 2021; Singh et al., 2023).
Fisheries
Fisheries on the IEGJM capelin stock took place in the 2024/2025 fishing season. A total of 9 439 t catches were fished during the winter of 2025 (Figure 1). Total historical catch of the stock is shown in Figure 1 by season and distribution of the catches of the Icelandic fishing fleet by year can be seen on Figure 2.
Changes in fishing technology and fishing patterns
A total of 9 439 t catches were fished during the winter of 2024/2025 fishing season primarily by purse seine. Historically, most of the catches have been taken in purse seine but a variable amount has been taken with pelagic trawl through the fishing seasons, related to the size of the TAC and when it is issued. Discards have been considered negligible.
Stock assessment
Capelin acoustic assessment surveys
The IEGJM capelin stock has been assessed by acoustics annually since 1978. The surveys have been conducted in autumn (September-December) and in winter (January-February). An overview is given in the Northwestern Working Group report NWWG, ICES stock annex.
Autumn survey 2025
Autumn surveys are conducted with the aim of assessing both the immature and the maturing part of the stock (Bardarson et al., 2024). Since 2010, the autumn surveys have started in September (and partly in late August), a month earlier than in the preceding years because of difficulties in covering the stock due to drift ice and weather during later months at the more north-westerly feeding grounds of the stock since early 2000s (Vilhjálmsson, 2007).
The survey was conducted on the behalf of MFRI by the r/v Arni Fridriksson and r/v Tarajoq on behalf of GINR (Greenland Institute of Natural Resources) (Figure 3). The survey area was on and along the shelf edge off East Greenland from about 64°30´N towards about 72°15´N, also covering the Denmark Strait and the slope off northwest Iceland. The Iceland Sea and Jan Mayen area were only briefly scouted due to time constraints and for same reason hydrographic measurements and zooplankton sampling were limited due to bad weather conditions. The initial planned survey tracks had to be changed due to stormy weather.
In general, drift ice only limited the coverage of the survey vessels in a few regions although icebergs and a lack of information on bottom topography occasionally affected routes and limited the extent of transects towards the Greenlandic coast (Figure 3).
Maturing capelin was mainly observed outside the Icelandic continental slope North and Northwest of Iceland (between 68-70°N and 20-22°W, see Figure 4). In the western Denmark Strait maturing capelin was mixed with immature capelin, while mainly maturing capelin was found further north east outside of Scoresby Sound. Similar to last year, the distribution of mature capelin reached only a relatively short distance east of Denmark Strait. Further, no capelin was found near the western part of the Jan Mayen ridge or further north of 71°N. Juveniles (0-group) of various species, including capelin (although not quantified) were observed along the continental shelf north and northwest of Iceland and along the southwestern coverage of the Greenlandic shelf. Immature capelin was found along the Greenlandic shelf, dominating in southwestern part of the survey area and close to the coast along Denmark Strait (Figure 4).
The total biomass of capelin estimate was 1 209 thous. tonnes of which the size of the mature part of the stock was 417.5 thousand tonnes. The immature part was 791 thousand tonnes. The index of the abundance of juvenile capelin was 118.9 billion, the 5th largest in the time series and indicating that the year class 2024 is large. Table 1 gives information on the age-disaggregated numbers and biomass of the capelin total stock.
The historical trend of mean weight of immature 1 to 3 year old capelin during the autumn survey is shown in Figure 5, as well as the trend of the mean weight of the mature capelin 1 to 4 year old capelin in Figure 6. The mean weight of 1 and 2 year old immature capelin has increased over time for all age classes, especially since 2000. Older age groups consistently show higher mean weights, with 3 year old immature capelin (Figure 5) and 4 year old capelin (Figure 6) exhibiting the most variability in mean weight.
Predation model results
Following the completion of surveys, estimations of stock parameters and their uncertainty 100 thousand bootstrap replicates of SSB were used as starting values for predation model runs. Results from the predation model runs are given in Table 2 and shown in Figure 8 and Figure 9.
| mean | 5% | 25% | 50% | 75% | 95% | |
|---|---|---|---|---|---|---|
| SSB | 228930 | 114130 | 171520 | 220030 | 277420 | 373140 |
| Predation | 124340 | 81930 | 103850 | 121730 | 141980 | 175660 |
The model (Ices 2023, ICES 2024) is designed to cover predation of cod, haddock and saithe on the main spawning migration of capelin and a schematic description of the model is shown in Figure 7.
The predation model (Ices 2023, ICES 2024) applies to the stock component that migrates the clockwise route around Iceland. In most years, majority of the stock has migrated that route and nearly all the catches have been taken from that component. All the capelin stock is assumed to be in the east on 15th of January, and on 15th of March, it is assumed that all the capelin stock spawns in the south and southwest, with a higher proportion in the southwest. The predators (cod, haddock and saithe) are assumed to be stationary during the period of capelin migration and their spatial distribution is obtained from the demersal survey in March from 1985 to the previous year. The total abundance of each predator is predicted for the current year based on assessment in the previous year.
Management
Agreed management plan and HCR
The Coastal States (Iceland, Greenland, and Norway) have agreed (Anon. 2015; Anon. 2023) to use the following harvest control rule as the basis for management, following the rule developed and revised by ICES (ICES, 2015; ICES, 2023).
The objective of the Harvest Control Rule is to set a final TAC which ensures, with a 95% probability, that a minimum of 114,000t (Blim) remains for spawning. This is achieved by a series of acoustic surveys from September - February and the TAC is determined in three stages; an initial TAC, an intermediate TAC and a final TAC.
The initial TAC for the next fishing season is set based on estimates of the immature part of the stock following an acoustic survey in autumn (September - October).
Two fixed points are defined:
Utrigger = 50 billion immature capelin.
TACMax = 400,000 tonnes for U > 127 billion immature capelin.
The method for setting the initial/preliminary TAC is:
TAC = 0 if Uimm < 50 billion.
TAC = 5.2 x (Uimm - Utrigger) thous. tonnes for Uimm in the range 50–127 billion.
TAC = 400,000 tonnes if Uimm > 127 billion.
The intermediate TAC for the current fishing season is set following the acoustic survey in autumn. Estimates on capelin spawning stock biomass (SSB) with uncertainty estimate are combined with data on predicted predator stocks size and distribution. The estimates are fed into a predation model run with varying catches until spawning in March. The intermediate TAC is set at 2/3 of the catch giving p(SSB < Blim = 114,000 tonnes) < 0.05.
The final TAC is set following an acoustic survey in winter (January-February). Estimates on capelin spawning stock biomass with uncertainty estimate are combined with data on predicted predator stocks size and distribution. Final TAC is set based on all acoustic surveys on the mature part of the stock from autumn to winter. The estimates are fed into a predation model run with varying catches until spawning in March. The final TAC is set at the catch giving p(SSB < Blim = 114,000 tonnes) < 0.05.
Initial advice 2025/2026
In June 2025, the initial advice for 2025/2026 was above the zero catch because the index for immature fish from the autumn acoustic survey 2024 was 58.9 billion, and was above the Utrigger value (50 billion). Based on this rule (see Section 6.1), the initial TAC would be 46 384 t for the fishing season starting 15 October 2025 to 15 April 2026 (Figure 10).
Intermediate advice 2025/2026
The results of the acoustic measurements in autumn 2025 (see section Section 4.2) on biomass of the mature part of the stock and accounting for the results of the predation model indicates that the goal of the harvest control rule of leaving at least 114 000 t for spawning with a 95% probability would be met with a catch of 65 650 tonnes. With the added precaution from the amended HCR (of setting TAC at 2/3 of that according to original rule), 43 766 tonnes is advised as the intermediate TAC for the fishing season starting 15 October 2025 to 15 April 2026.
Benchmark history
Since early 1980s the stock was managed according to an escapement strategy, leaving 400 000 tonnes for spawning and the uncertainty of the estimates was not considered.
A new HCR and management plan were developed at an ICES benchmark meeting in 2015 and adoped the same year (ICES, 2015). The main changes involved accounting for uncertainty in the measurements and in the predation on the capelin stock up to the spawing period. At the ICES benchmark meeting in 2022 (ICES, 2023), minor adjustments were made, which the coastal states meeting agreed to base the advice on. Among other things, these changes included lowering the Blim from 150 000 tonnes to 114 000 tonnes (Figure 11).
Reference points
Blim was set at 114 000 tonnes by WKCAPELIN (ICES, 2023). No other reference points are defined for this stock.
State of the stock
The fishable stock was estimated to a median of 480 314 tonnes in autumn 2025 . The predation model (ICES, 2015), accounting for catches and predation by cod, saithe and haddock between surveys and spawning, estimated SSB to 228 930 tonnes which were left for spawning in spring 2026 (Table 2). Given the uncertainty estimates, there was 95% probability that at least 114 000 tonnes was left for spawning, if the catches taken amounted to 43 766 tonnes. The acoustic estimate of immature capelin from the autumn survey in autumn 2025 was 118.9 billion. Initial advice for the fishing season 2026/27 on the basis of that amount will be issued by ICES and MFRI in June 2026.
The fishable stock was estimated to a median of 404 314 tonnes in autumn 2025. The predation model (ICES, 2015), accounting for catches and predation by cod, saithe and haddock between surveys and spawning, estimated median SSB left for spawning in spring 2026 as 228 930 tonnes (Table 2). Given the uncertainty estimates, there was 95% probability that at least 114 000 tonnes was left for spawning, if the catches taken amounted to 43 766 tonnes. The acoustic estimate of immature capelin from the autumn survey in autumn 2025 was 118.9 billion. Initial advice for the fishing season 2026/27 on the basis of that amount will be issued by ICES and MFRI in June 2026.
The estimated SSB at spawning time (March-April) has been recompiled for 1981-2025 (Figure 13), using the model adopted in 2015 and 2023, i.e. taking into account uncertainty in the acoustic measurements and using the predation model adopted in 2015. Uncertainty in acoustic measurements was recompiled for the years 2002-2006 and 2012-2014 by recalculating the acoustic indices and bootstrapping the results. Additionally, uncertainty was available for the years since 2015 when the advice was given based on the new HCR. For earlier years, the CV in the acoustic measurements was estimated by looking at survey reports as well as text from (Vilhjálmsson, 1994). The estimated CV was in the range of 0.15-0.25 and was included as a lognormal multiplier on available average values from the same sources.
Uncertainties in assessment and forecast
The uncertainty of the assessment and forecast depends largely on the quality of the acoustic surveys in terms of coverage, conditions for acoustic measurements and the aggregation of capelin (i.e., high patchiness leads to high variance).
The uncertainty is estimated by bootstrapping (see WKICE 2015). The CV for the immature abundance was estimated to 0.11 in the 2025 autumn survey. The survey had a low coefficient of variation (CV=0.2) for the mature stock estimate.The spatial coverage of the autumn survey in 2025 is considered to have covered the distribution area of the stock. There is some uncertainty regarding the distribution of immature capelin in the autumn survey due to the lack of calibration of the 18kHz on the r/v Tarajoq and therefore difficulties to separate immature capelin from 0-group. However, this uncertainty does not affect the assessment results.
While the autumn survey was affected by time constraints the distribution of immature and mature components of the capelin stock seemed to have been covered.
The role of capelin in the ecosystem
Capelin is an important forage fish and its dynamics are expected to have implications on the productivity of their predators.
The importance of capelin in East Greenlandic waters is not well documented but the effort has increased considerably during autumn surveys towards evaluation of capelin’s role in the ecosystem e.g. by research on feeding of capelin, estimates of prey availability, predators’ distributions and environmental monitoring.
In Icelandic waters, capelin is the main single item in the diet of Icelandic cod, a key prey to several species of marine mammals and seabirds and also important as food for several other commercial fish species (see e.g. Vilhjálmsson, 2002, Singh et al., 2023). Diet studies of cod from the groundfish survey in March clearly demonstrate the importance of capelin in its diet, while also showing the variability in capelin availability between years (Figure 14).
Regulations and their effects
Over the years, the fishery has been closed during April–late June and the season has started in July/August or later, depending on the state of the stock.
Areas with high abundances of juvenile age 1 and 2 capelin (on the shelf region off NW-, N- and NE-Iceland) have usually been closed to the summer and autumn fishery.
It is permissible to transfer catches from the purse seine of one vessel to another vessel, in order to avoid slippage. However, if the catches are beyond the carrying capacity of the vessel and no other vessel is nearby, slippage is allowed. In recent years, reporting of such slippage has not been frequent. Industrial trawlers do not have the permission to slip capelin in order to harmonize catches to processing.
In Icelandic waters, fishing with pelagic trawl is only allowed in limited area off the NE-coast (fishing in January) to protect juvenile capelin and to reduce the risk of affecting the spawning migration route (shuttering of migrating capelin schools by pelagic trawling has been hypothesized).
As a precautionary measure to protect juvenile capelin, the coastal states (Iceland, Greenland and Norway) have agreed that beginning 2021, fishing shall not start until 15. October.
References
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Anon. 2023. Framework arrangement between Greenland and Iceland on the conservation and management of capelin. 2023. Reykjávik, Iceland 3 July 2023. 4 pp. https://www.althingi.is/altext/pdf/154/fylgiskjol/s1655-f_I.pdf Last accessed: 31 May 2025.
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