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Festive seasonal price trends in a selection of Fish and Shellfish species Guest ArticleAccompanying document
Seasonal price trends in a selection of fish and shellfish species were found in an analysis of monthly data over the
period of 2002 to 2012. The figures below show the average price (blue line) and the quantity of stock landed
(grey line) over this period. The red spots on the graphs indicate the month of December, whilst the blue squares
that appear in some figures, but not all, indicate March.
Consistent December peaks in price were found in Monkfish, Scallops, Edible Crab and Nephrops caught by creel
(Figures 1 to 4). This could be linked to a festive change in the fish market. Figures 1 and 4 both show a second
consistent, although slightly less convincing, price peak in March for Monkfish and Edible Crab. Haddock and Cod
do not appear to have price peaks in either December or March.
In Figures 2 to 6, unsurprisingly, the trend in the quantity of stock landed mirrors the trend in fish prices; as
quantity landed decreased, price increased. Regression analysis was performed to establish whether the
relationship between the quantity of fish landed and the price was statistically significant (at the five per cent
level) for each fish species. In all species, bar Monkfish, there was a significant negative relationship between
quantity landed and price. Interestingly, the regression analysis performed on Monkfish prices and quantity
landed resulted in a non-significant result (F1,130= 1.46, co-efficient of variation (co-ef))= -0.29). This means that the
evidence suggests that the festive peak , and other peaks, in Monkfish price were not linked to dips in the
quantity landed.
This study into seasonal price trends does not investigate the reasons why there are price peaks, and associated
landing dips, that appear during the Christmas period of December. Or why the price of Monkfish does not have
the same strong relationship between the quantity of stock landed, like other species. This study identified that
there are price peaks and quantity dips during the festive period, and that there is a common relationship
between fish price and quantity if stock landed. There are other variables that could have relationships with the
price of fish. These are not investigated here but could be looked in further studies.
Figure 1: 2002 - 2012 Monthly Price and Quantity Landed – Monkfish
2002 -------------------------------- 2006 ----------------2009------------------------- 2012
Time
Red dots indicate the December period and blue squares indicate March. During the Christmas period (Dec) the price of
Monkfish peaks. Slightly less convincing peaks in price occur in March as well. Regression analysis tested the relationship
between price and weight. It resulted in a negative but non-significant relationship between the two variables (F1,130= 1.46,
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co-ef= -0.29). This is interesting as it goes against what might be expected. This non-significant result could be due to a high
level of underlying variation in the Monkfish data.
Figure 2: 2002 - 2012 Monthly Price and Quantity Landed – Nephrops caught by Creel
2002 ----------------------------- 2006 ----------------2009------------------ 2012
Time
Red dots indicate the December period. During the Christmas period (Dec), the price of Nephrops caught by Creel peaks.
Regression analysis revealed a significant negative relationship between the quantity landed and the price of Nephrops
(F1,130=7.43, co-ef = -6.78). This suggests that the peaks in prices around December are, at least partly, linked to the dips in the
quantity landed.
Figure 3: 2002 - 2012 Monthly Price and Quantity Landed – Scallops
2002 ----------------------------- 2006 ----------------2009------------------ 2012
Time
Red dots indicate the December period. During December the price of Scallops peaks. Regression analysis revealed a
significant, but small, negative relationship between the quantity landed and the price of Scallops (F1,130=25.17, co-ef = -0.39).
This suggests that the peaks in prices around December are, at least partly, linked to the dips in the quantity landed.
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Figure 4: 2002 - 2012 Monthly Price and Quantity Landed – Edible Crab
2002 ----------------------------- 2006 -----------------2009------------------------ 2012
Time
Red dots indicate December and blue squares indicate March. During the Christmas period (Dec) the price of Edible Crab
peaks. Slightly less convincing peaks in price occur in March. Regression analysis tested the relationship between price and
weight landed. The analysis resulted a significant, but small, negative relationship between the quantity landed and the price
of Edible Crab (F1,130=23.95, co-ef = -0.45). This suggests that the peaks in prices around December are, at least partly, linked
to the dips in the quantity landed.
Figure 5: 2002 - 2012 Monthly Price and Quantity Landed – Haddock
2002 ----------------------------- 2006 -----------------------2009---------------------- 2012
Time
Red dots indicate the December period and blue squares indicate March. Unlike Figures 1 to 4, there are no consistent peaks
in December or March, it actually appears to dip. Regression analysis revealed a significant, but slight, negative relationship
between the quantity landed and the price of Haddock (F1,130=87.48, co-ef = -0.19).
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Figure 6: 2002 - 2012 Monthly Price and Quantity Landed – Cod
2002 ----------------------------- 2006 -------------------------2009-------------------- 2012
Time
Red dots indicate the December period and blue squares indicate March. Similarly to Figure 5, there are no consistent peaks
in December or March. Regression analysis revealed a significant, but slight, negative relationship between the quantity
landed and the price of Cod (F1,130=29.81, co-ef = -0.41).