General information
The underlying data and assumptions for the assessment and advice on fishing opportunities on lumpfish in Icelandic waters are introduced here. Juvenile lumpfish are non-shoaling, mainly pelagic and are distributed in open water throughout the Norwegian Sea, Denmark Strait and Irminger Sea. When they mature, lumpfish migrate to coastal areas around Iceland to spawn with males arriving January-February and females arriving February-March. During the migration, females exhibit a mix of pelagic and demersal behaviour. The weight of the roe close to spawning can account for 25-35% of female body weight. Lumpfish show pronounced sexual dimorphism, with the males maturing at a smaller size (~25-35 cm) than the females (~35-45 cm) and the males have an intense red colouration during the spawning season. The females lay the eggs in nests in shallow water and the male will then guard the eggs until they hatch.
Commercial fishery
There are two separate fisheries for lumpfish, a small scale male fishery (less than 40 tonnes per year) for the flesh and a much larger female fishery (typically 2 to 10 thousand tonnes per year) where the primary target is the roe.
The female fishery takes place from March until August, and uses gillnets with a mesh between 267 and 292 mm. More than 99% of the landings of females are from the directed female fishery. The female fishery takes place close to shore and is located in Faxaflói Bay, Breiðafjördur and along the northern coast (Figure 1). Landings from the female fishery peaked between late 1970’s and 1980’s (Figure 2). Between 1980 and 2021, landings have fluctuated between 2 and 13 thousand tonnes. Pre 2008, landings have been estimated from the number of barrels of roe produced with the numbers being provided by the National Small Boat Owners Association. From 2008, it became mandatory that all landings are recorded in a similar manner to all other fisheries in Iceland, however it was still legal to dispose of the bodies at sea so the majority of landings consisted of only roe. In 2012, it became mandatory to land the bodies but an exception has been made for 2021 and 2022 due to market conditions. As there is currently no TAC on either of these fisheries, there is no incentive to discard lumpfish, however as of 2019, it is legal to release male lumpfish caught while targeting females.
The male fishery takes place in only a few locations along the coast (Figure 3) from January to March and uses gillnets with a mesh of between 178 and 203 mm. Approximately 20-60 tonnes of male lumpfish are landed each year with the directed fishery making up between 2 and 56% of the total landings per year between 2003 and 2024 (Figure 3). Other landings of males come from the female fishery and from other gears (cod gillnets, demersal seine and bottom trawls). The effort in the cod-gillnet fishery increased from 2002-2006 and then decreased from 2006-2020 which is reflected in the landings of male lumpfish. This decrease of landings from the cod gillnet fishery partially accounts for the wide range in the percentage of total landings from the male fishery.
Estimation of historical landings
As landings data was not routinely collected before 2008, the landings before this period are estimated from number of barrels of roe produced with this data being provided by the National Association of Small Boat Owners. The method used to do this is described in Kennedy and Jónsson (2020). In summary, information from fisher logbooks is used to estimate the average weight of roe in a fish and the amount of fresh roe that is needed to fill one barrel of roe. The values currently used are 29.4% of the weight for the average amount of roe per fish and that it takes 139 kg of fresh roe to fill one barrel. This equates to 472 kg of ungutted lumpfish per barrel of roe, thus the weight of the landings of lumpfish (tonnes) = 0.472 * number of barrels.
Landings of roe that are recorded by the Directorate of Fisheries are converted to weight of whole lumpfish using the formula \[\textrm{W}_{lump} = \textrm{roe} \times \textrm{ 1.25 } \times \frac{\textrm{100}}{\textrm{29.4}}\]
where Wlump = weight of whole lumpfish and roe = weight of landed roe. When roe is landed, 20% of the weight is deducted to account for the fluids and this is the weight recorded by the directorate of fisheries. It is assumed the roe accounts for an average of 29.4% of the weight of the fish.
Management and previous advice
The female lumpfish fishery is an effort controlled fishery with limits placed on the total length of nets, total number of fishing days and total number of boats. The total number of boats is limited as boats must have, in addition to a valid commercial fishing licence, “Grásleppuréttindi”, a permit which allows the boat to fish for lumpfish. In March 2024 there were 420 boats with Grásleppuréttindi. No new permits are issued, and a permit can only be obtained by transferring it from one boat to another. However, there is currently no system which can prevent all boats with a valid permit taking part in the fishery of one particular year. To participate in the fishery for the current year, a boat with a permit to fish lumpfish must inform the Directorate of Fisheries that they will activate the license for that year.
Up until 2020, the coastline around Iceland was divided into 7 areas (Figure 1), each area was open for lumpfish fishing for approximately 2.5 months. Each boat had to select an area for that year and could not fish in another. The licence allowed fishing for female lumpfish for an allocated number of days within the time period in which that area was open, each boat choosing a continuous period within the open season. The area system was abolished in 2020 and boats were free to move between areas, except for the inner Breiðafjörður area (B2) which opens later (20th May) than the other areas. The area system was reinstated in 2021. There are a number of areas which are closed for lumpfish fishing to lower the bycatch of marine mammals (Figure 5).
The primary method to limit catches of female lumpfish is by altering the total number of days that each boat can fish for. The number of days is set annually by the Minister of Fisheries and Agriculture and is based upon an advised TAC for female lumpfish from MFRI and discussions with stakeholders. MFRI have been advising on a TAC since 2012 (Table 1), which is given in tonnes (see Advice section below). The fishery can be effectively closed by the Directorate of Fisheries by cancelling all lumpfish licences if it is foreseen that fishing could become harmful with regards to the sustainable exploitation of the stock.
The only restrictions on the male fishery are the period in which a male lumpfish net can be used (1st January – 15th June) and the mesh size and height of the net. There is no TAC and MFRI does not issue advice on a TAC.
Effort and catch per unit effort (CPUE)
The number of boats participating in the female fishery is influenced, alongside other factors, by the market price of the roe. Pre-1996, the number of boats participating in the fishery was higher, varying approximately between 290 and 450 per year (Table 1). Post 1996, the number of boats has varied from 140 to 363. However, the number of nets per boat has increased between these two periods, while the number of days for which each boat can fish has decreased (Table 1). The number of boats participating in the male fishery has varied between 1 and 17 between 2001 and 2023 (Figure 4).
The CPUE is estimated from fisher logbooks and is calculated as the weight of catch divided by the number of nets (Figure 6). The CPUE of the female fishery has varied over time and is influenced both by the biomass of the population and by the effort itself.
Length composition of landings
Pre 2012, obtaining length measurements from the female fishery was difficult due to the removal of roe before landing and disposing of the bodies at sea. Due to a change in regulations in 2012, the majority of landings consist of ungutted lumpfish. The landings are aggregated at a small number of locations for processing making it more straightforward to sample from the fishery. Mean length of fish caught in the female fishery is around 38-41 cm with limited variation between years (Figure 7), this is primarily due to the limited length range in the population and the selectivity of the gillnets.
Biomass indices
Data from the IS-SMB is currently used as the basis for tracking trends in biomass of the female lumpfish population (Figure 8). This survey covers a large part of the temporal and depth distribution of mature female lumpfish. Data from the annual gillnet survey is also taken into account as supporting information (Figure 8). In general, the biomass index for females from the IS-SMB was high between 1985-1990, low during the 1990´s and at roughly intermediate levels during the 2000’s. It decreased during the early 2010’s but has recently increased to intermediate levels. The length distribution has changed over time (Figure 9), with females ≥ 45 cm being more abundant during 1985-1990 than in the years post 1990. The abundance of large females reached a minimum in 1997 but has gradually increased since then, with the abundance in 2017 being the highest since 1990 (Figure 8).
Catchability of male lumpfish in the IS-SMB seems to be very poor and the trends are not considered to reflect the real changes in the population (Figure 10). There has been little change in the length composition of males over time (Figure 9).
FPROXY
An index of relative fishing mortality for lumpfish is derived from the IS-SMB and landings of whole lumpfish (Fproxy = Yield/Survey biomass index) (Figure 11).
Advice
In 2020, the lumpfish assessment went through a benchmark assessment (Kennedy et al. 2021) together with representatives from the Ministry of Fisheries (Fiskistofa), the fishing and processing industry. It was concluded that historical catches estimated from the number of barrels reported to the NASBO on an annual basis pre-2008 was not suited for input into the assessment. A new harvest plan was agreed which came into force in the 2021 assessment.
The results of the benchmark concluded that the use of a constant exploitation rate is appropriate for this stock and that recent historical catches (2008-2020) suggest an exploitation level of 0.75, the exploitation level used in setting the advice from (2013-2020), is likely sustainable.
The lumpfish biomass index fluctuates considerably between years, therefore, the index from the current fishing year is taken into account when considering the advice. To compensate for uncertainty in the measurements, the previous year’s index is also taken into account. The current year’s and previous year’s survey are giving a weighting of 70 and 30% respectively. The advice from the MFRI based on target Fproxy is thus given in two stages, an initial TAC based upon the biomass index of the preceding year and a final TAC based upon the current biomass index.
The advisory rule (Figure 12) now includes a biomass safeguard which entails the application of a linear reduction in the target Fproxy when the biomass index (I) falls below the level of a precautionary trigger Itrigger set at 1.4*Ilim. As the advice is made up of two components, calculated from I from the current year and the previous year, then, if I is equal to or below Ilim, in the current year or previous year, then that year will represent a value of zero in the calculation of TAC. Ilim was set at the historical minimum of the biomass index in the reference period 1985-2020 (Table 1).
| Year | Boats | Nets | Fishing.days | SMB.index | Advice | Landings.DF | Landings.other |
|---|---|---|---|---|---|---|---|
| 1980 | 343 | 50 (150) | 7926 | 0 | |||
| 1981 | 347 | 50 (150) | 10798 | 0 | |||
| 1982 | 219 | 50 (150) | 3615 | 0 | |||
| 1983 | 292 | 50 (150) | 5214 | 0 | |||
| 1984 | 384 | 50 (150) | 12637 | 0 | |||
| 1985 | 401 | 50 (150) | 10273 | 10798 | 0 | ||
| 1986 | 298 | 50 (150) | 9546 | 7624 | 0 | ||
| 1987 | 350 | 50 (150) | 12052 | 10798 | 0 | ||
| 1988 | 334 | 50 (150) | 9887 | 4815 | 0 | ||
| 1989 | 353 | 50 (150) | 12680 | 6372 | 0 | ||
| 1990 | 234 | 50 (150) | 10461 | 3068 | 0 | ||
| 1991 | 356 | 50 (150) | 4283 | 4673 | 0 | ||
| 1992 | 393 | 50 (150) | 8180 | 6137 | 0 | ||
| 1993 | 326 | 50 (150) | 6092 | 4200 | 0 | ||
| 1994 | 401 | 100 (300) | 5756 | 5504 | 0 | ||
| 1995 | 417 | 100 (300) | 4682 | 5315 | 0 | ||
| 1996 | 447 | 100 (300) | 4628 | 4922 | 0 | ||
| 1997 | 372 | 100 (300) | 5177 | 6313 | 0 | ||
| 1998 | 277 | 100 (300) | 4454 | 3065 | 0 | ||
| 1999 | 258 | 100 (300) | 7091 | 3266 | 0 | ||
| 2000 | 266 | 100 (300) | 3859 | 2380 | 0 | ||
| 2001 | 197 | 100 (300) | 5513 | 3167 | 0 | ||
| 2002 | 222 | 100 (300) | 10132 | 4887 | 0 | ||
| 2003 | 272 | 100 (300) | 7259 | 6033 | 0 | ||
| 2004 | 353 | 100 (300) | 9012 | 5599 | 0 | ||
| 2005 | 256 | 100 (300) | 60 | 7163 | 3613 | 0 | |
| 2006 | 163 | 100 (300) | 50 | 12896 | 3898 | 0 | |
| 2007 | 144 | 100 (300) | 50 | 8841 | 3196 | 0 | |
| 2008 | 205 | 100 (300) | 50 | 7879 | 5717 | 216 | |
| 2009 | 265 | 100 (300) | 62 | 8020 | 5726 | 105 | |
| 2010 | 338 | 100 (300) | 62 | 6995 | 9357 | 236 | |
| 2011 | 363 | 100 (300) | 50 | 4970 | 5240 | 219 | |
| 2012 | 334 | 100 (300) | 50 | 7467 | 3700 | 6558 | 434 |
| 2013 | 282 | 200 | 32 | 4285 | 4000 | 4652 | 299 |
| 2014 | 221 | 200 | 32 | 6322 | 4300 | 4011 | 332 |
| 2015 | 316 | 7500m | 32 | 9041 | 6200 | 6357 | 604 |
| 2016 | 239 | 7500m | 32 | 8901 | 6800 | 5385 | 622 |
| 2017 | 246 | 7500m | 36 | 8241 | 6350 | 4513 | 52 |
| 2018 | 218 | 7500m | 46 | 6937 | 5487 | 4469 | 48 |
| 2019 | 240 | 7500m | 44 | 6173 | 4805 | 4967 | 77 |
| 2020 | 202 | 7500m | 44 | 7260 | 5200 | 5193 | 122 |
| 2021 | 173 | 7500m | 40 | 14108 | 9040 | 7465 | 136 |
| 2022 | 175 | 7500m | 25 | 7233 | 6972 | 4197 | 138 |
| 2023 | 165 | 7500m | 45 | 5352 | 4411 | 3802 | 206 |
| 2024 | 140 | 7500m | 55 | 5403 | 4030 | 3746 | 216 |
| 2025 | 3994 | 2766 | 0 | 0 |
References
ICES 2020. Tenth Workshop on the Development of Quantitative Assessment Methodologies based on LIFE-history traits, exploitation characteristics, and other relevant parameters for data-limited stocks (WKLIFE X). ICES Scientific Reports. 2:98. 72 pp. http://doi.org/10.17895/ices.pub.5985
James Kennedy og Sigurður Þ. Jónsson 2020 .Umreikningur á fjölda tunna af grásleppuhrognum yfir í óslægðan afla byggður á veiðdagbókum. Haf- og vatnarannsóknir. HV- 2020-32. 9 bls. https://www.hafogvatn.is/static/research/files/hv2020-32.pdf [in English: Converting number of barrels of lumpfish roe to ungutted landings based on logbook data. HV- 2020-33, 9 pp. https://www.hafogvatn.is/static/research/files/hv2020-33.pdf]
James Kennedy, Sigurður Þór Jónsson, Höskuldur Björnsson, Guðmundur J. Óskarsson, Bjarki Þór Elvarsson, Guðmundur Þórðarson (2021) Report on benchmark assessment and revision of an advisory rule for lumpfish around Iceland. KV 2021-1. Kver Hafrannsóknastofnunar https://www.hafogvatn.is/static/research/files/kv2021-1.pdf