The purpose of the Total Allowable Catch (TAC) method is to manage stocks sustainably, and, by fixed quota percentage, to divide landings proportionately among member states which, on the basis of traditional harvesting patterns have entitlement to exploit them.
The process involves assessing fish stocks to ascertain the fraction which can be removed without jeopardising regenerative capacity. The operation has been central to the Common Fisheries Policy (CFP) since the early 1980s. In spite of this, there has been little critical scrutiny of its efficacy in Ireland to date.
Once a TAC for a stock has been decided, usually in December for the following year, the quantity is broken by fixed key into allocations to member states. In Ireland, the Department responsible for fisheries, then “rations the quota” on a monthly basis to the fleet. It is Departmental policy to fill all quotas.
A study in 2014 demonstrated that more than half of the demersal quota species categories were not filled despite generous monthly allocations by the Department; more than 300 times the individual quota of one species was offered to the fleet which was unable to fill a single quota for it. This was interpreted as a genuine depletion of the species in question. Throughout these accounts landings are interpreted as proxy for stock biomass. The 2014 study was based on the distribution of quota in a single year and it prompted a wider enquiry. This, presented here, examines the harvest of the principal quota categories within demersal (finfish and Nephrops) and pelagic divisions. Their yield to the Irish fleet (tonnes landed annually) and the percentage of landings to quota (ie the percentage filled quotas) are examined for the period 1998 – 2016 inclusive. This period, which coincides with a dramatic decline in landings (Fig 1) was chosen because the Stock Book series published by the Marine Institute covers the nineteen years; it contains relevant data enabling the study to take place. Sources and the limitations of data (below) contains commentary.
Eighteen quota species were considered in this appraisal: 12 demersal, 6 pelagic; two demersal species combinations, angler/monk, skates & rays; total demersals, total pelagics and a sum total of all were examined: 22 entities (Table 1). Landings to the Irish fleet and landings as a percentage of quota were plotted and trend lines fitted over the 19 year period, the longest time series. If the slope of either trend line altered less than 10% over the time series, it was regarded as “level” for evaluation purposes.
This review attempts to peruse a sequence from worst to best performance to which end the results are presented in six groups.
Group 1 presents the worst scenario in which landings as a percentage of quota declined over the period while landings also fell, in other words, falling quotas failed to arrest stock decline. Blue whiting and boarfish (two species on which the new Biomarine Ingredients factory in Killybegs depend) observed this trend. Saithe, ling and plaice belong in this group also. Examples of boarfish and plaice are provided in Fig 2.
Group 2 is one in which landings as a percentage of quota were level throughout while landings fell; it is represented by sole (Fig 3). The data suggest that while quotas were not exceeded, there was a decline in the stock over the period; lower quotas would appear to be desirable in this, as in the preceding group.
Group 3 contains entities showing increasing landings as a percentage of quota while landings declined and the group includes herring, haddock, cod and skates & rays. These results imply that such declining landings as were recorded consisted to some extent of over-quota fish. Cod and herring are provided as examples (Fig 4).
Group 4 contains entities whose landings as a percentage of quota increased, whereas landings remained level throughout, suggesting that over-quota fish were the means by which landings were sustained. Pollock, whiting and all demersal species displayed this pattern, the second and third of these entities being cited as examples (Fig 5).
Group 5 has entities whose landings as a percentage of quota and landings both remained level, a pattern shown by mackerel and horse mackerel and also the case for all pelagics and all species, demersal and pelagic combined. Mackerel is the subject of Fig 6.
Finally, Group 6 contains five entities, Nephrops, angler/monk, megrim, hake and albacore, all of which responded positively to policy: landings as a percentage of quota increased while landings themselves also displayed an upward trend. The interpretation of these trends may not be straightforward although it suggests a more sustainable regime. Nephrops and hake are shown as examples (Fig 7).
Responses to quota management
Ten species, three of them pelagic, the remainder demersal, are placed in Groups 1-4; all require an adjustment of quota policy which, over the period of the review, would appear to have been too generous. Using the annual landings presented in Table 1 as an indication of their comparable size, these account for some 48% of all demersal species listed in Table 1 but they also represent a declining sub-division of this category because their landings trend downwards over the series. Similar statements can be made about the three pelagic species which, in common with all of the pelagics listed here, belong to much larger stocks than demersals; nonetheless, pelagic species in groups 1-4 represent more than 48% of the landings of all pelagic species, a similar percentage.
The average percentage of landings to quota over the series ranged from 29% for plaice through 50% for sole, 71% boarfish, 90% pollock, 100% haddock, 158% angler/monk; this statistic stabilised at 100% for Nephrops, 93% for all demersals bulked and 96% for all pelagics bulked and 95% for all species combined. The fact that the landings to quota ratio and the landings of bulked species approximated suggests that the objective of “filling species quotas” might be satisfied by combining species, some responding negatively to quota management, others exceeding quota limits, to obtain a less precise but acceptable outcome; this is a different perspective on the stated objective of Departmental policy.
Quota management is clearly more successful for those clean single-species fisheries which characterise pelagic stocks. Demersal stocks of various biomass sizes, exploited with unselective gears, respond in different ways; the smaller tend to reduce further over time while effort is geared towards harvesting the more abundant.
The practice of setting quota values too high is undesirable because it attracts effort to harvest fish which are not available (sole is a case in point) with consequent discarding of other, over-quota and by-catch species in the process.
Sources and the limitations of data
Any assessment of this kind is handicapped by the quality of available data. Two principal sources were consulted. Landings, by species, were obtained from the government department responsible for fisheries and thereafter, the Sea Fisheries Protection Authority (SFPA) which came into existence as a result of legislation in 2006 when it assumed the task of reporting these statistics. These are primary sources for such data. There is no alternative to accepting them as a true account of fish catches although there is reason to be sceptical; in 2003-2004, for example, there was an investigation by the fraud squad of landings to Ireland. Multiples of quota were reportedly brought ashore illegally but there was no adjustment of the official record as a result.[i] On occasion, corroborative confirmation of landings was sought in the Marine Institute’s Stock Book but that was not always satisfactory. In 2009 for example, landings of hake exceeding 6 times the quota were reported but specific tonnage was not provided in the Stock Book. Instead, the text reassured: “The TAC was overshot considerably between 2000 and 2005 but since 2006 landings have been below the TAC”, which appears to have prioritised diplomacy. Such landings data as were provided by the Marine Institute concern only quota species and the departmental and SFPA figures used by this writer and covering all landings have been relied on elsewhere on this website.
The other statistic used, the weight of quota per stock for the principal species is as reported in the Marine Institute’s annual Stock Book.[ii] This publication contains details of quota-stock assessments for the year of its publication and a number of statistics in summary form of particular relevance to Ireland.
Quotas are decided by a fixed key division of the agreed TAC but the reality can be more complex. Hague preferences could gift a greater proportion than determined by the quota formula to Ireland, quota “pay-back” for over-fishing in previous years has been known to reduce the tonnage of mackerel and swops of some smaller quotas in return for a share of others are commonplace. Here, it has been necessary in some cases to calculate quotas from first principles from the fixed percentage of the TAC due to Ireland when precise adjusted data have not been provided in the summary tables which accompany most issues of the Stock Book but, wherever possible, the exact figures have been discovered in the detailed text describing assessments of individual stocks.
[i] Fahy, E. (2013) Overkill! Self published, P 321
[ii] The stock book (1998-2016), published by the Marine Institute, Galway. On-line from the year 2000. Available at http://oar.marine.ie/handle/10793/14/simple-search?query=stock+book+2016