|
|
ACTIVITIES
REGIONAL RESEARCH |
|
| Updated on 07/5/2001 |
Note: This Web page has been designed based on the Final Report of this project (EC, DG XIV, 97/0018). See PDF Version.
Table of Contents:
The primary purpose of the methodology employed was more to collect qualitatively accurate data than quantitative data per se, with a view to being able to put forward advisory and management strategies based on reliable information. Visits by observers to the fishing ports for purposes of sampling were conceived as a method of validating/calibrating the quality of the data supplied by the skippers through the logbooks and also as a method of collecting first-hand information where logbooks could not be accepted by fishermen. To that end, once or twice a week sampling was performed in the ports considered when the fishing vessels returned to port, to record the size of landings together with supplementary information from skippers on the number of hauls, towing duration, fishing locations, etc. in the period just previous to the sampling date. Results indicate that the deep-water shrimps fishing fleet consists of trawlers and multi-purpose vessels equipped with trawl nets. Catch per unit effort data on A. antennatus are most abundant for the Western Mediterranean, off mainland Spain and North Africa. High catches of this species in these areas coincide with low catches of A. foliacea. Generally the location of rose shrimp (A. antennatus) fishing grounds varied seasonally and were located between 400 and 950 m. Spatio-temporal movements are well described in the literature and submarine canyons play and important role as fishing grounds. For each area the fishing ground locations have been described and its concrete location can be found in the data bank. The profit margin after cost coverage is quite low in most ports. The residual amount has to be used to cover financial costs (depreciation and opportunity cost- interests) and, above all, to remunerate the managerial factor. In fact the highest profit margins are recorded in the ports of Almeria, Mazara del Vallo and Villa Real di San Antonio, i.e. where the rose shrimp fishing fleet is managed at industrial level. All collected data are given in a GIS presentation in the attached CD and in a data bank. Along the development of this project on the Mediterranean deep-sea shrimp fishery we faced a general major problem: the difficulty to collect reliable data to characterise the targeted parameters. These referred to a vast array of concepts necessary to deal with the main features of the fishery, and ranged from the amount of catches to the power of the engines or the actual value of landings. Keywords: Aristeus antennatus, Aristaeomorpha foliacea, Deep-sea, Red shrimp, Rose shrimp, Fisheries, Catches, Efforts, Economics, Mediterranean Sea, North Africa.
Participants:
COPEMED area teams involved:
The study area encompasses the Mediterranean (coasts of Spain, and Italy) and adjacent areas of the Atlantic (Algarve, Portugal), including North Africa (Tunisia, Algeria, Morocco) (Figure 1). It represents a first opportunity for simultaneous and comparative co-operation with the countries of North Africa. COPEMED (FAO) agreed to fund the corresponding part of the study in North Africa. A total of 29 effective ports around the Western and Central Mediterranean were sampled (Table I). |

Figure 1: area of deep-sea shrimps exploitation
|
TABLE I |
|||||
COUNTRY CODE |
REGION |
PORT |
PORT CODE |
ADMINISTRATIVE REGION |
REGION CODE NUMBERS* |
PO |
Algarvian |
Vila Real de Santo Antonio |
VRS |
Algarve |
26 |
SP |
N. Alboran |
Almeria |
ALM |
Andalucía |
16 |
SP |
S. Levant |
Santa Pola |
SPO |
País Valencià |
19 |
SP |
S. Levant |
Vila Joiosa |
VIL |
País Valencià |
19 |
SP |
Catalonian |
Barcelona |
BCN |
Catalunya |
17 |
SP |
Catalonian |
Blanes |
BLA |
Catalunya |
17 |
SP |
Balearic |
Palma |
PAL |
Illes Balears |
20 |
IT |
Ligurian |
Santa Margherita Ligure |
SML |
Liguria |
07 |
IT |
Ligurian |
Sestri Levante |
SLE |
Liguria |
07 |
IT |
N. Tyrrhenian |
Porto Ercole |
PER |
Toscana |
13 |
IT |
C. Tyrrhenian |
Formia |
FRM |
Lazio |
06 |
IT |
S. Tyrrhenian |
Salerno |
SAL |
Campania |
03 |
IT |
S. Tyrrhenian |
S. Maria di Castellabate |
SMC |
Campania |
03 |
IT |
S. Tyrrhenian |
Marina di Camerota |
CMR |
Campania |
03 |
IT |
N. Sicilian |
Terrasini |
TRS |
Sicilia |
12 |
IT |
N. Sicilian |
Trapani |
TRP |
Sicilia |
12 |
IT |
Sardinian |
Oristano |
ORS |
Sardegna |
11 |
IT |
Sardinian |
Sant'Antioco |
STT |
Sardegna |
11 |
IT |
Sardinian |
Cagliari |
CGL |
Sardegna |
11 |
IT |
Sardinian |
Arbatax |
ARB |
Sardegna |
11 |
IT |
G. Taranto |
Gallipoli |
GAL |
Puglia |
10 |
IT |
S. Sicilian |
Mazara del Vallo |
MZV |
Sicilia |
12 |
IT |
S. Sicilian |
Portopalo di Capopassero |
PCP |
Sicilia |
12 |
IT |
S. Sicilian |
Sciacca |
SCC |
Sicilia |
12 |
TU |
Tunisian |
Bizerte |
BIZ |
Tunisie Nord |
38 |
TU |
Tunisian |
Kelibia |
KEL |
Tunisie Nord |
38 |
AL |
Algerian |
Algiers |
ALG |
Centre |
31 |
AL |
Algerian |
Cherchell |
CHE |
Centre |
31 |
MO |
Moroccan |
Nador |
NAD |
Eastern Mediterranean |
35 |
*code numbers are related to those of figure 1
|
The collected data are: catch (biomass) and fishing effort data for the target species (Aristeus antennatus, Aristaeomorpha foliacea), the species composition and abundance (biomass) catch data for the major by-catch species, the seasonal size-frequency distributions of the target species, the location of the main fishing grounds in each subsector of the study area throughout the year, and the economic aspects of the fishery, costs and benefits. The primary purpose of the methodology employed was more to collect qualitatively accurate data than quantitative data per se, with a view to being able to put forward advisory and management strategies based on reliable information. Visits by observers to the fishing ports for purposes of sampling were conceived as a method of validating/calibrating the quality of the data supplied by the skippers through the logbooks and also as a method of collecting first-hand information where logbooks could not be accepted by fishermen. To that end, once or twice a week sampling was performed in the ports considered when the fishing vessels returned to port, to record the size of landings together with supplementary information from skippers on the number of hauls, towing duration, fishing locations, etc. in the period just previous to the sampling date. Generally the location of rose shrimp (Aristeus antennatus) fishing grounds varied seasonally and
were located between 400 and 950 m. (Table II). Spatio-temporal
movements are well described in the literature and submarine canyons
play an important role as fishing grounds. For each area the fishing
ground locations have been described and its concrete location can be
found in the data bank. |
|
TABLE II GENERAL INFORMATION BY REGION |
||||||||||||||||
|
Region |
Alv. |
Alb. |
S.L. |
Cat. |
Bal. |
Lig. |
N.T. |
C.T. |
S.T. |
N.Si. |
Sar. |
Tar |
S.Si. |
Tun. |
Alg. |
Mar. |
|
Max. Bethymetic distribution catches |
650 |
800 |
800 |
980 |
800 |
800 |
800 |
700 |
800 |
800 |
800 |
720 |
800 |
¿? |
500 |
400 |
|
Specific shrimpers |
N |
Y |
Y |
Y |
Y |
Y |
Y |
Y |
Y |
Y |
Y |
N |
Y |
Y |
N |
N |
|
Is Aa
a target species |
Y |
Y |
Y |
Y |
Y |
N |
Y |
Y |
Y |
Y |
Y |
Y |
Y |
N |
Y |
N |
|
Is Af.
a target species |
N |
N |
N |
N |
N |
Y |
N |
Y |
Y |
Y |
Y |
Y |
Y |
N |
Y |
N |
|
Shrimp fishing grounds |
Y |
Y |
Y |
Y |
Y |
Y |
N |
Y |
Y |
N |
Y |
Y |
N |
N |
Y |
N |
|
Fishing grounds exploited by different fleets |
Y |
Y |
Y |
Y |
Y |
Y |
Y |
Y |
Y |
Y |
Y |
N |
Y |
Y |
Y |
N |
|
Max. effective work (h) |
18 |
12-72 |
12 |
12 |
13 |
11 |
11 |
11-72 |
11 |
8-96 |
14 |
14 |
8-96 |
48-72 |
18 |
N |
|
Effort is know exactly |
Y |
N |
N |
N |
N |
N |
N |
N |
N |
N |
N |
N |
N |
N |
N |
N |
|
Catches are know exactly… |
Y |
Y |
Y |
N |
Y |
N |
N |
N |
N |
N |
N |
N |
N |
N |
N |
N |
|
Sold in different ports |
Y |
Y |
Y |
Y |
Y |
N |
Y |
Y |
Y |
Y |
Y |
Y |
Y |
Y |
Y |
N |
|
Official landings reliables |
Y |
Y |
Y |
N |
Y |
N |
N |
N |
N |
N |
N |
N |
N |
N |
N |
N |
|
Logbooks acceptable |
Y |
Y |
Y |
Y |
Y |
N |
N |
N |
N |
N |
N |
N |
N |
N |
N |
N |
|
In the Ligurian Sea, Eastern Italy,
and the islands of Sardinia and Sicily, catch per unit effort (CPUE)
data on A. antennatus are not as readily available, while CPUE
data on A. foliacea become increasingly available.
Taking these two species together, mean yields are around 4.2 kg/h,
with peak values of 9 kg/h, which translates into approximate mean
daily yields of about 50 kg/day. (Fig. 2 & 3). On the whole, the
data indicate that there is a tendency to catch the species A.
antennatus alone in the westernmost part of the Mediterranean,
whereas the two species are mixed in the easternmost portion of the
study area.
Figure 2: CPUE by species
Figure 3: CPUE by species There were seasonal variations in
catches both within species and between species. Throughout the
Mediterranean, the highest rose shrimp (A. antennatus) yields
were attained in summer, the lowest yields in autumn. (Figure 4) In
contrast, the highest red shrimp (A. foliacea) yields were
attained in winter and spring. On the whole, in the Western and
Central Mediterranean A. antennatus yields were higher than A.
foliacea yields. (Figures 5 & 6).
Figure 4: CPUE
Figure 5: CPUE A. antennatus
Figure 6: CPUE A. foliacea The range of the length frequency distribution for the total annual catch at each port studied may seem similar, but the relative importance of each size in the total catch varies. The size distribution of the total annual catch represents both different conditions of exploitation and particular aspects of species biology. (Figures 7 & 8).
Figure 7: annual size distribution of A. Antennatus females for an each area
Figure 8: annual size distribution of A.
Antennatus males for an each area In the UE countries (no data are
available from North Africa), the economic results of a fishing
business are directly related to its fishing effort (Tables IV &
V). A correct economic analysis must then relate the economic
variables to the effort data. The most efficient port was the port of
Almeria (Table VI). Efficiency is surely positively related to the
size of the vessels (when the size increases, output increases more
than proportionally); however it is also affected by other factors,
such as the age of the fleet, modernization, equipment, and last but
not least, the opportunity of choosing different fishing areas without
being forced to share the same area with all vessels coming from the
same port or from neighboring ports (as it is the case in the Ionian
channel). |



|
|

