NEAR EAST

BAHRAIN

BAHRAIN SHRIMP FISHERY AND THE MARINE ENVIRONMENT

by Ebrahim A. A. Abdulqader, National Coordinator (Bahrain Center for Studies and Research; P.O. Box 496; Bahrain)

PREFACE

The preparatory phase of a global project on reducing the impact of tropical shrimp trawling fisheries on living marine resources through the adoption of environmentally friendly techniques and practices started in January 1999 and ended in June 2000.

The activities carried out by Bahrain during the project development phase included: 1) organizing a local workshop on 28 July 1999 entitled Workshop on reducing the impact of Bahrain shrimp fisheries on the marine environment by adopting environmentally friendly techniques and practices, 2 conducting an opinion survey using the FAO standard questionnaire (The results were published in a separate report (Uwate and Abdulqader, 1999), 3) preparing and printing a pamphlet (1 000 copies), 4) writing two reports, first on the results of the opinion survey and the second being the national report here'in included.

1. INTRODUCTION

Total shrimp landings were 2 571 tonnes in 1997 and formed 25.6% of Bahrain's total landings. Value at first sale was 3.5 million Bahrain Dinars (Fisheries Statistical Section, 1998a). This is equivalent to US$ 9.3 million. During the period 1980 to 1997, maximum shrimp landings were 3 565 tonnes in 1996, while lowest was 752 tonnes in 1992 during the Gulf war.

Shrimp is the most valuable species landed in Bahrain. Despite its importance, the shrimp fishery can play a negative role on the marine environment. This is due to the use of the trawl net, which is a low selective gear. In addition to shrimp, trawls pick up quantities of other fauna inhabiting the seabed. Shrimp trawls may contribute towards lowering the bio-diversity of the marine habitat. This report introduces the Bahrain shrimp fishery, and highlights its interaction with the marine environment.

2. THE HISTORY OF THE BAHRAIN SHRIMP FISHERY

Traditionally, the tidal barrier trap (local name: Hadhrah) was the y2859e gear used for shrimp fishing in Bahrain. These traps are usually placed against the direction of shrimp migration. The importance of these traps in the local shrimp fishery was reduced after the introduction of trawling in 1967 (FAO, 1978). At present, trawl nets are responsible for most shrimp landings in Bahrain.

Bahrain Fishing Company (BFC) was the first established company to commercially exploit shrimp resources. This company started its fishing operations in March 1967 (FAO 1978). American and Japanese markets were the y2859e purchasers of shrimp catches, most of which were exported as headless shrimp (Boreama and Job, 1968).

In the first two years of its operation, BFC operated eight trawlers. Eight more trawlers were soon added in 1968. Further, two more boats were added to the fleet in 1973 (FAO, 1978). In 1976 some of these trawlers were replaced and the total number reduced to 15 boats (FAO, 1978). All trawlers were double rigged (outrigger trawlers), using Gulf of Mexico trawl nets. Their headrope length ranged from 14 m in the case of small boats, to 17 m in the case of big boats. Mesh sizes of these nets ranged from 45 to 50 mm. All boats were steel hulled; their length ranged from 15 to 23 m.

BFC was the only company allowed to fish in Bahrain waters. The fishing season of this company usually started in Maniffa grounds off Saudi Arabia during July and August. From September to February, both Saudi and Bahrain grounds were fished (FAO, 1978). Total landings of this sector included the catches from both Bahrain and Saudi waters (Boerema and Job, 1968; Boerema, 1969; FAO, 1973; FAO 1978).

After a sharp decline in catches in the 1978/79 season and in the early 1979/80 season, shrimp trawling became uneconomical and the BFC ceased fishing in August 1979 (Abdulqader, 1983). A revival of the industrial sector of the Bahrain shrimp fishery started in 1980/81, but it experienced low catch rates. This fleet operated 4 double rigged trawlers which had been trawling for fish since 1975.

The artisanal trawl fishery started in 1971 (Abdulqader, 1983) by fishermen previously involved in the barrier trap fishing. In 1976, there were 26 full time shrimp trawlers in this category y2859ely operating from Sitrah jetty. All of these boats were made of wood known locally as "banoush". After the implementation of the registration and a licensing scheme in 1983, shrimp trawlers increased to 68 boats (Abdulqader, 1988). In 1985, the number increased to 495, with small boats forming 54% of the total.

From 1971 to 1985 artisanal shrimp fishermen were manually hauling the nets. Winches were introduced in 1986 by the Directorate of Fisheries. In 1997 about 86% of the fleet were equipped with winches.

Since the start of the artisanal shrimp fishery, the Sitrah pier was the y2859e landing site for this sector. This was due to the closeness of this site to the y2859e artisanal fishing grounds. After the implementation of a shrimp fishing ban period in 1980/81 (Abdulqader, 1982), the northern grounds became more important to the artisanal fleet. With that change the Manama landing site became an important shrimp landing site. The shrimp fishing ban regulation, and the introduction of winches, shifted the artisanal fleet to exploit deeper waters in the north.
Shrimp landings from industrial and artisanal fishing fleet are presented in Figure 1. High landings were observed for the industrial fleet before the crash of the fishery in 1979. The second period of industrial landings started in 1980 (Figure 1).

The increase in the size and fishing power of the artisanal fleet resulted in a gradual reduction of the industrial fleets role in shrimp fishing. The latter fleet was able to fish only for a few weeks of the season. In 1997, a decree was issued to totally ban fish trawling in Bahrain waters. This decree resulted in the removal of all industrial boats from the shrimp and fish fisheries. These boats had become dependent on fish trawling.

Figure 1. Shrimp landings from artisanal (solid line)
and industrial sectors from 1967/68 to 1993/94 fishing seasons.
(Source: FAO 1978, and Fisheries Statistical Services, 1998a)

From 1998, the Bahrain shrimp fishery was based only on the artisanal fleet. This fleet has grown over time and thus became very efficient. The word "artisanal" is no longer valid to define Bahrain's shrimping sector. A commercial sector is a more appropriate term to describe the present shrimp trawl fisheries

Catch and effort statistics for the Bahrain shrimp fishery are shown in Table 1. These statistics started with the second industrial sector period in 1980 and include the present time (1997/98). Effort data were standardized to artisanal effort units (Abdulqader, 1995). Due to the changing fishing behaviour of the artisanal sector throughout this period, standard effort was calculated based on the catch rate ratios for each season. The standard effort was calculated by converting the industrial fishing hours to artisanal hours using the following equation:

Where F is the total standard effort

FA is the artisanal effort

FI is the industrial effort

UI is the industrial catch rate

UA is the artisanal catch rate

TABLE 1. Shrimp total catch and artisanal, industrial, and standard effort
for the 1979/80 to 1997/98 shrimping season

SEASON	Catch In Tonnes	EFFORT IN FISHING HOURS (x 1 000)			CATCH Rates
		Artisanal	Industrial	Total
80/81	625.5	27.0	5.1	34.6	18.1
81/82	543.5	24.1	6.0	46.8	11.6
82/83	685.4	37.5	8.6	75.1	9.1
83/84	727.5	42.0	10.2	80.7	9.0
84/85	778.1	54.1	10.4	93.6	8.3
85/86	1444.2	54.6	7.2	87.1	16.6
86/87	1313.2	66.7	5.3	97.7	13.4
87/88	1695.1	86.7	11.9	146.0	11.6
88/89	1072.6	145.6	12.5	184.4	5.8
89/90	1258.2	158.0	15.3	176.4	7.1
90/91	1150.8	154.4	7.3	186.5	6.2
91/92	620.4	153.8	4.0	162.7	3.8
92/93	806.7	178.6	3.5	187.6	4.3
93/94	2079.3	229.5	1.8	234.7	8.9
94/95	1115.5	226.4	1.4	256.8	4.3
95/96	1666.0	232.2	.5	234.0	7.1
96/97	3799.8	316.2	1.6	319.1	11.9
97/98	2247.0	366.6	1.1	371.9	6.0

Source (Fisheries Statistical Section, 1998a)

Total catch and standard effort are shown in Figure 2 for seasons 1980/81 to 1997/98. Clear increasing trend in the effort appeared from 1986/87 season. Catch varies with the highest peak being in the 1996/97 season. After the collapse of the fishery in the late 1970s, low catches were seen till the 1984/85 season. Similar low catches were seen again in the post Gulf war period, in the 1991/92 and 1992/93 seasons.

Figure 2. Shrimp total catch (bars, in tonnes) and standard fishing hours (x 1 000)
for Bahrain shrimp fleet for the season 1980/81 to 1996/97.
Source (Fisheries Statistical Section, 1998a)

The 1980/81 and 1985/86 high catch rates (Figure 3) were during periods of reduced fishing effort. The 1985/86 high catch rates (Figure 3) stimulated an increase in effort. This caused the decline in catch rates of the successive seasons.

3. SHRIMP FISHERIES STATISTICS COLLECTION METHODS

For shrimp fishery, two schemes are currently used in the collection of statistics.

First scheme is based on the stratified random sampling (Abdulqader, 1986). This scheme originally allows three visits for each major landing site in a month. In each day, landing and fishing efforts are recorded per boat, per fishing gear, and per fish species. The total daily shrimp landings and efforts are estimated by multiplying the average landing per boat by total number of boats landed at the sampling day. Monthly landings and effort are estimated by multiplying the average daily estimates of three sampling days by number of landing days.

As the sampling is conducted in the landing sites, the sampling scheme generates statistics on shrimp landings not on shrimp catches. In case of Bahrain, most of shrimp catches are landed. Landing statistics, therefore, were considered to represent catch statistics. Fishing hour is the unit used to represent the fishing effort. Complete statistics were produced by this scheme since 1979 until the present time.

Figure 3. Standard catch per unit of effort for the seasons 1980/81 to 1997/98.

Since 1985, a logbook or reporting scheme expanded to all shrimp fishing boats (Abdulqader, 1988). Earlier, this scheme was used for the industrial steel-hulled boats. Shrimp skippers/owners are required to record their daily fishing activities in a monthly standard report (Appendix 1). Submission of the fishing reports is a prerequisite to boat licensing.

Unlike the sampling scheme, the logbook scheme provides catch statistics related to the fishing grounds. This logbook scheme provides more detailed catch and effort statistics. Statistics generated by this scheme have not been published yet.

The fishing logbooks scheme provided the basis for development of the Shrimp Fisheries Monitoring Program (SFMP). This program utilizes several database types including: logbook data, boat and owner registration details, fishing area details, shrimp sizes (number per kg), boat price, engine price, winch price, fish price, and cost of fishing (Abdulqader and Mehic, 1996). SFMP generates reports in the form of tables, figures and maps. Catch, effort and catch per unit of effort can be presented for any selected time period and boat size in a map format. Based on shrimp size data, the program has a subroutine to convert shrimp catches to numbers, and to display shrimp density in various grounds. The system contains a subroutine to generate cost and revenue reports for a selected time period and boat size.

The SFMP is now operational, but still it is not providing information to the fisheries managers because there is a shortage in budget and staff.

4. THE SHRIMP FISHERY

Shrimp resources

Seven penaeid species were found in Bahrain waters (Abdulqader, 1999). Commercial shrimp landings are y2859ely from a single species, Penaues semisulcatus. The six other rey2859eing species makes about 5% of the annual shrimp landings. Two species P. latisulcatus and Metapenaeus kutchensis grow to good size. The rey2859eing four species M. stebbingi, Trachypenaeus curvirostris, Metapenaeopsis stridulans, and M. mogiensis are smaller and are usually partially or entirely discarded. Catches of small sized shrimp frequently exceed the amount of big shrimp catches at the end of the season (February and March).

The shrimp fishing grounds extend from a depth of 2 to 20 m. There are three major shrimping areas: western, northern and southern area. The approximate locations of the shrimp fishing grounds were determined with fishermen's assistance (Abdulqader & Mehic,1996) and are illustrated in Figure 4. Fishermen identified fifty shrimp fishing grounds within Bahrain waters. Local names are used to identify these grounds. Total shrimping area is estimated at about 871 km². Ghumais fishing ground located at the south, is the biggest fishing ground (area 163 km²), it makes up 18.7% of the total shrimping area. The second important ground is Umm-Adood (area 105 km²) found in the north, which makes 12.1% of the total shrimp grounds.

Fishing Vessel and Gear

Bahrain shrimp fishing boats vary in size and composition. Wood is the traditional material used in boatbuilding. Recently, the number of fibreglass boats has increased. Low y2859etenance cost and lighter weight are to the advantage of the fibreglass boats which fishermen now prefer.

Regardless of the building material used; all big and medium size boats are built following the traditional boat design which is well known in the Arabian Gulf area and adjacent seas. Banoush is the local name used for these boats.

Most of big and medium boats are equipped with winches, while in most of the small boats, nets are retrieved manually. Most of the fishing boats use second hand car engines or diesel engines to power their winches. Also many shrimp boats use hydraulic winches.

In the 1997/98, thetotal number of shrimp boats was 335 boats. About 14% of these boats had no winch; 49% were fibreglass boats. For the shrimp season, 306 boats were licensed (for some reason 29 boats did not renew their fishing licence).

Figure 4. Bahrain shrimp grounds within three y2859e areas.
Major coral reefs (Fasht AlJarim, Fasht AlAdhom, and Fasht AlDebil)
and land areas also indicated.

During the 1997 shrimp closed period, all shrimp boats were examined and their specifications were verified and recorded. This includes boat, engine, winch specifications. These records were entered in the SFMP. The 1997 data on fishing fleet specification are the most recent information on the fleet. Detailed description of the fleet is presented below. These results were obtained from the SFMP.

Boat Size Frequency Distribution

Bahrain shrimp fleet includes boats from 5 to 23 m in total length. The majority of these boats are about 16 m length. The Bahrain fleet contains a considerable number of small boats. Length frequency for all shrimp boats, with and without winch included, is shown in Figure 5.

Figure 5. Number of boats found within specific size class for all boats.

Figures 6 shows length frequency distribution of boats with winch and Figure 7, those without winch. Most boats without winch are small and most operate in shallow waters.

Figure 6. Number of boats found within specific size class for all boats with winch

Figure 7. Number of boats found within specific size class for all boats without winch

Boat Age Distribution

The SFMP provides information about the boat age. Figure 8 shows the age distribution of Bahrain shrimp fishing fleet in year 1998. In Bahrain's shrimp fleet there are boats more than 28 years old. Most boats are between 0 to 26 years old. Many boats are new to the fishery.

Figure 8. Number of boats found within specific age class for all boats

Boat Engine Horsepower Distribution

All boats used in the present shrimp fishery are powered either with outboard (class A boats), or inboard engines. Engines of 300, 200 and 50 horsepower are most common in the Bahrain shrimp boats (Figure 9). The 450 horsepower engines are used by steel hulled boats. These steel boats were banned from the Bahrain shrimp fishing fleet in 1997.

Figure 9. Number of boats found within specific engine horsepower class for all boats

Boat Origin

Most of Bahrain shrimp boats were built in Bahrain and the United Arab Emirates (Figure 10). Most of boats built in UAE are fiberglass big boats, while most boatsbuilt in Bahrain are wooden boats.

Figure 10. Frequency of shrimp boats per country of origin. BAH = Bahrain,
UK = England, IND = India, JAP = Japan, KUT = Kuwait, OM = Oman, QAT = Qatar,
SA = Saudi Arabia, SW = Sweden, UAE = United Arab Emirates

Shrimp Fishing Nets

A single net of the Gulf of Mexico flat type is used per fishing boat. According to the boat size, nets varied in size from 5 to 24 fathoms footrope lengths. Cod ends are usually made of 1.182 inches (30mm), 65 twin netting. The rey2859eder of the net is usually made of 1.5 inches (38mm), 35 twin netting. One or two rows of chains (8mm thickness) are usually used. Nets equipped with two rows of chain are towed in higher speed.

Doors used with net are made of wood. Steel is used in these doors to support wood pieces, and to form the door base. The common door used is 140cm length by 70cm width, and about 80 kg in weight.

Fishing Technology

Most of shrimp fishermen depend on GPS navigation in their fishing operations. Fishermen realized the importance of GPS in minimizing sailing time and preventing the loss of nets. GPS stores the co-ordinates of hazard locations, which will enable the fishermen to avoid dangerous locations during their fishing. Most large boats use both GPS and echo sounders. Several large boats are using mobile phones to communicate between boats, and between boats and land.

5. SHRIMP FISHING PRACTICE

Shrimp fishing in Bahrain is a daily operation. Boats usually depart from the jetties in the late afternoon and return just after sunrise. In seasons of high catch rates, shrimp fishing can be done during the daytime at the beginning of the season. However, Bahrain shrimp fishing is y2859ely a night operation.

All shrimp fishing boats trawl with a single net. These nets are released from the stern of the boats. The release of the doors and the forward movement of the boat facilitate the movement of the net to the sea bottom. Nylon rope of about 26mm diameter is usually used to haul the trawl net. This rope is stored on the winch, which is usually mounted toward the bow of the boat.

Trawling by big and medium boats is normally conducted at about 3.5 knots. However, some of the big boats use double chain rows on the footrope of large nets (over 20 fathom footrope). They are able to trawl at 5 knots speed. Practically, the boats with more chain on their trawl which are sweeping bigger area have more fishing power than those using a single row of chain. However, this practice reduces engine life.

Trawl duration varies with the boat size and the catch quantities. Small boats trawl for 15 minutes in cases of high catch rates, while the trawling period may extend to one hour when catches are low. This is because net hauling is carried out manually. Bigger boats may trawl up to two hours. Despite the use of a winch, there are limitations for hauling the bag onto the deck which is usually done manually.

The catch is sorted into shrimp, crab, and commercial fishes. The rey2859eing catch is discarded at the sea. This last portion usually includes non-commercial fish, juveniles of commercial fishes and occasionally marine turtles. At end of the season, catches usually contain significant quantities of small shrimps other than P. semisulcatus. These shrimp are partially kept during the periods of high market demand.

After sorting the catch, the shrimp is usually washed with seawater and stored in chilled brine. Shrimp catches are usually stored in 40 kg insulated boxes. Shrimp catches are kept in these boxes during the transfer to the auction market.

6. SOCIAL ASPECTS

Previously, the term artisanal was used to distinguish the smaler wooden boats from the steel hull ones. The artisanal fleet is now dominant in the shrimp fishery in term of fishing power. The term artisanal is not used anymore to describe this sector. Detailed specifications of Bahrain's shrimping fleet are discussed in section 4.

In 1976, among the 26 wooden boats, ranging from 6 to 17 m in length, involved on a full time basis in shrimp fishing (FAO, 1978), 18 were operating from Sitrah pier. Their fishing area was restricted to the shallow areas found in the south and around Muharaq Island. All fishermen working on these boats were Bahraini (personal observation). Boats were managed on a family basis and, normally, own by their captains. Fishing revenues were distributed y2859ely to members of the family. As trawling was introduced only in 1971, the experience of these fishermen was limited. Nets were retrieved manually, resulting in the use of small nets and the need for relatively large crew.

From the mid 1980s, the number of foreign fishermen on shrimp boats increased because they were less costly. Also, use of foreign workers was encouraged by the government to meet country development requirements in all sectors. This resulted in the appearance of another type of boat ownership. The new owners were investors who did not directly participate anymore in shrimp fishing and depended on foreign crews. Using foreign crews allowed the owners/investors to operate several boats. Now, some owners own up to 7 boats. About 95% of the shrimp fishermen are foreigners.

Foreign fishermen come from different cultures, but primarily from India. A considerable percentage of these fishermen possesses only a basic education.

The increase in foreign fishermen has resulted in less Bahraini going for fishing. A number of Bahraini, former fishermen, now owns and manages two or more boats.

Most of the shrimp fishing boats are found at three y2859e landing sites. These are Manama, Sitrah, and Muharaqe pier. The basic services (electricity, water and jetty) are found in these landing sites. Dry docks and mooring areas are available for hull y2859etenance.

Most of the shrimp fishing boat owners use the share system for distributing the catch revenue. This is done on a daily, weekly or monthly basis. Costs of fishing (fuel, oil, water and ice) are calculated and subtracted from the total shrimp revenue. The resultant amount is divided into two halves. One half goes to the boat owner as depreciation and y2859etenance cost for the boat and engine. The second half is divided into shares. One share is for each fisherman (including the captain). In addition one share is for the car driver and another share for the boat winch. The boat captain receives an additional half share from the owner of the boat.

7. CATCH AND EFFORT DISTRIBUTION BY FISHING AREA AND BOAT SIZE CLASS

As already mentioned, a special computer program known as Shrimp Fisheries Monitoring Program (SFMP) was developed for the processing of the fishing log data (see section 3). Only 1997/98 data has been entered in this programme and a summary of catch and effort data produced by SFMP is presented in this section. For the 1997/98 nine and half months shrimp seasonthe total catch was 2507.9 tonnes and effort estimated by SFMP to 416.2 thousand of hours. These estimates are about 11% higher than the estimates provided by sampling scheme (see section 3), which are, for the same season, a total catch of 2247.0 tonnes for an effort amounting to 371.9 thousand hours.

Shrimp catch and effort distribution by boat size

The Shrimp Fisheries Monitoring Program (SFMP0) has classified the shrimp boats into 5 classes, i.e.: class A (<= 5.9 m); class B (6 - 10.9 m); class C (11 - 15.9 m); class D (16 - 25.9 m); and class E (=> 26 m) classes.

A summary of 1997/98 season is produced in Table 2. Catch rate increases with increase in boat sizes class. Boats class D were responsible for most shrimp catches. Boat class A had the lowest catch rate.

TABLE 2. Boat size class, catch, effort (x 1 000 trawl hours), and catch rate (kg/ trawl hour)
for the season 1997/98. SFMP outputs

Catch, effort, and catch per unit of effort for different boat sizes and months are presented in Tables 3, 4, and 5 respectively. For the period July 1997 to March 1998, the catches were the highest the first month (Table 3). This month, the Effort was slightly higher than effort in successive months (Table 4). The catch per unit of effort of the boats more than 11 m (Class C and D) was also found the highest in July 1997 (Table 5). It is worth observing that in February and March 1998 the smaller boats (class A) had to stop fishing because they were not able to move to deeper waters where the bigger boats caught the shrimp.

TABLE 3. Shrimp catches (in tonnes) per month by boat size class for the 1997/98 season. (SFMP outputs)

MONTH	Size A	Size B	Size C	Size D	TOTAL
July 97	0.2	21.8	169.0	555.1	746.1
August	0.3	9.8	104.8	253.7	368.6
September	0.05	11.4	79.1	193.4	283.9
October	0.1	10.6	73.9	173.5	258.0
November	0.04	8.4	64.9	162.2	235.6
December	0.1	6.4	51.1	153.6	211.2
January 98	0.004	3.3	35.6	124.4	163.3
February	0	2.6	27.3	86.2	116.2
March	0	2.2	32.0	90.7	125.0
Total	0.8	76.5	637.8	1792.9	2 507.9

Catch and Effort Distribution by Fishing Ground

A summary of 1997/98 catch and effort data per fishing ground is provided in Table 6.

About 66% of efforts were spent in Ummdood and Ghamais fishing grounds. These are the y2859e fishing grounds in the northern and southern areas respectively. Further, about 69% of total catch was taken from these two grounds. Catch rates in these grounds were 6.5 and 6 kg/hr.

TABLE 4. Effort (in thousands of hours) per month by boat size class for the 1997/98 season. (SFMP outputs)

MONTH	Size A	Size B	Size C	Size D	TOTAL
July 97	0.1	3.4	18.8	33.9	56.1
August	0.1	1.5	17.2	31.4	50.1
September	0.05	2.5	15.2	28.8	46.6
October	0.05	2.6	16.3	30.6	49.5
November	0.05	2.3	16.3	31.7	50.3
December	0.1	2.1	14.4	31.7	48.3
January 98	0.002	1.5	11.3	28.2	40.9
February	0	1.2	9.7	24.2	35.1
March	0	1.0	11.5	26.8	39.3
Total	0.4	17.9	130.6	267.3	416.2

TABLE 5. Catch per unit of effort (kg / fishing hour) per month
by boat size class for the 1997/98 season. (SFMP outputs)

MONTH	Size A	Size B	Size C	Size D
July 97	2.1	6.5	9.0	16.4
August	2.7	6.7	6.1	8.1
September	0.9	4.6	5.2	6.7
October	1.5	4.1	4.5	5.7
November	1.1	3.71	4	5.1
December	1.2	3.1	3.5	4.8
January 98	2	2.3	3.2	4.4
February	0	2.2	2.8	3.6
March	0	2.2	2.8	3.4

High catch rates, more than 10 kg/hr, were found in several grounds: Buoy 25, Ras Albar, and Al hadid Wasalb E (Table 6) but, however, the effort was little. Green buoy and Red buoy grounds in the north, and Shaik Ebrahim island received a considerable amount of fishing effort but the Catch rates from these areas were lower than from Ummdood and Ghamais.

The lowest catch rate was recorded from Tubli Bay (Table 6). The effort was also little in this area were usually only small boats (Class A) fish.

8. SHRIMP BY-CATCH ASSESSMENT

"By-catch" is a group name used to identify all fauna (except for shrimp) found in the catches of shrimp trawls. The word "discard" is a group name used to identify by-catch species being discarded at sea because of their low economic value. These definitions are adopted in this report.

TABLE 6. Total catch, effort, and catch per unit of effort (kilo per hour) per fishing ground
for the 1997/98 shrimping season, see Figure 4 for location of these grounds. (SFMP outputs)

FISHING AREA	CATCH IN TONNES	EFFORT (x1000 hours)	CATCH RATE
Aleslah	81.6	12.3	6.7
Khur Fasht NW	10.8	1.5	7.3
Albab	2.3	0.4	6.2
Aldoba	1.0	0.2	3.9
Green Bouy	122.6	21.8	5.6
Red Bouy	111.0	20.8	5.3
E Doba	3.2	1.2	2.6
Aljarim E	0.4	0.2	2.2
Ummdood	970.3	149.3	6.5
Bouy 15	42.2	5.8	7.3
Bouy 25	32.4	2.5	13.0
Alghazarah	4.0	0.9	4.2
Tubab	18.3	2.0	9.0
Qitat Jaradah	24.6	4.5	5.5
Tubli Bay	1.4	0.7	2.1
Mina Sulman	13.1	4.9	2.7
Dry Dock	30.3	6.2	4.8
Al hadid Wasalb E	52.8	5.2	10.1
Asheeb	6.8	0.7	9.6
Trekat N	0.2	0.04	4.3
Pump house	2.2	0.8	2.9
Alhadher	0.5	0.1	4.2
Shaik Ebrahim island	140.0	30.3	4.6
Tal Hayan	0.3	0.1	2.3
Ummjalid	14.3	2.6	5.6
Jaw	23.6	5.6	4.2
Reg Ghamais	1.3	0.4	3.5
Ghamais	767.3	128.8	6.0
Tighilib W	19.1	4.4	4.4
Mishtan	6.6	1.4	4.7
Ras Albar	0.7	0.1	12.6
Umm Alnassan	1.7	0.3	5.1
Buoy 3	0.3	0.1	3.7
TOTAL	2507.1	416.0	6.0

In Bahrain, by-catch generated by trawling activities has been studied for a relatively long period. This topic is still considered as one of the most important areas of current research work. From the 1980s until the present time, three major by-catch studies have been conducted. The first was carried out for 13 months paralleling the first shrimp survey (from June 1980 to June 1981). The second study was carried out for two years (from January 1983 to February 1985). This work assessed both fish and shrimp trawl by-catch. The third by-catch study is conducted parallel to the present GCC regional shrimp survey. This survey started in March 1999 and will continue for two years.

First Shrimp Survey (June 80 to June 81)

Details of this study were documented in Abdulqader, 1986. In the study, one industrial fishing vessel was allocated for this survey for 3 days per month. The sampling was conducted under normal fishing conditions, but using a single Gulf of Mexico flat trawl. The size of the net used was 27 m at the headrope.

Sampling was conducted at fixed stations. These stations (27) were selected within the defined limits of Bahrain's shrimp fishing grounds (Figure 11). Each sampling station was trawled once a month for 45 minutes.

After sorting the shrimp, big and small fish were recorded by weight. The number of fish was also recorded in the case of big fish. The weight was obtained either by visual estimation (in the case of big fish), or by using standard baskets. A 5 kg random sample was collected from each sampling station. In the laboratory, these samples were sorted to species level. Number and weight of different species were recorded. Records were also collected on the incidental catches of sea turtles, the number and estimated weight of which were recorded.

During this survey, more than 90 fish species were identified in the shrimp by-catch. In addition, several invertebrate species were also found in the by-catch. The scientific names of these species and their family or group names are presented in Appendix 2.

Species occurrence was used to assess the abundance of the species in shrimp by-catch (Abdulqader, 1986). Species occurrence is a ratio of the stations where the species were present, to the total stations trawled during the month. For this calculation, only the qualitative data were used. Occurrence values ranged from 1, when a species was present in all stations, to 0 when a species was absent from all sampled stations. The overall occurrence is calculated by simple averaging of monthly figures.

Based on this survey, the overall occurrence was calculated for each species (Abdulqader, 1986). The various species were categorized according to their occurrence score into dominant (>0.5), common (0.3 - 0.5), less common (0.1-0.3), occasional (0.01-0.1), and rare species (<0.01). Based on occurrence score, 11 species were dominant in the shrimp by-catch, these are, Gerres oyena, Paramonachanthus sp., Pomadasys stridens, Scolopsis taeniatus, Upeneus tragula, Lethrinus lentjan, Selaroides leptolepis, Siganus canaliculatus, Nemipterus bleekeri, Rhabdosargus haffara, and Upeneus sulphureous. Also 6 species were found common, 27 species less common, 41 species occasional, and 14 species were rarely observed.

The first shrimp survey produced a by-catch assessment key (Abdulqader 1986). This key shows catch rates per species for 45 minutes fishing for each sampling month.

By-catch Assessment Program (February 1983 - January 1985)

This second study assessed by-catch taken by the industrial trawling fleet. This includes both shrimp and fish trawling. At that time, the industrial fleet was responsible for most by-catch generated by trawl fisheries. It is worth mentioning that at that time the reporting scheme had not yet been developed to include the artisanal sector which anyway started increasing significantly only in 1985. Industrial fishing boats were required to submit monthly reports on their fishing activities. Standard forms for both fish and shrimp fishing were provided to every fishing boat. In these reports, skippers were requested to report on their fishing activities on a daily basis. For the by-catch assessment program, an additional form was provided to the skippers. In this form, the skipper was to record on a daily basis, haul after haul, the target species (shrimp or fish), the weight of total catch, quantity of shrimp, fish block number and the weight of the by-catch per haul (the weight of small fishes was recorded in number of standard baskets).

Figure 11. Map showing the fixed stations trawled
during the first shrimp survey conducted from June 1980 to June 1981

For by-catch estimation purposes, the entire fishing ground was divided into 10 nautical mile grids. This resulted in 182 grids.

One basket of small fish was randomly collected per fishing day. At the laboratory, these samples were sorted to the species level. Weights of each species in the samples were recorded. Species weight ratios of the sample were used to estimate the weights of these species in the total by-catch.

Data on fleet activities were provided in the standard fishing forms. The total number of hauls conducted in a month was estimated from these forms. Average by-catch weight per haul was used to estimate monthly total by-catch in each fishing block. Fishing effort was estimated in the same way.

Most of the calculations have been completed. The final report summarizing these data has not yet been written. Time and computer limitation prevented the full analysis of these data.

GCC (second) Shrimp Survey (March 99 to February 2001)

Under the Gulf Co-operative Council (GCC) umbrella, in March 99, Kuwait, Saudi Arabia, Bahrain and Qatar started to conduct a regional shrimp survey. This survey is on going and includes a monthly sample for two years. Each country is responsible for conducting the survey in their own waters at randomly selected grids. The shrimp area was divided into 3 miles grids. Each grid was defined by a unique alphanumeric code. All concerned countries adopted standard nets and fishing practices. Only commercial fishing boats are used in this survey.

For Bahrain, 57 fishing blocks were identified within the three y2859e shrimp areas: west, north, and south (Figure 12). In each month, 50-60% of the fishing blocks are randomly selected. Each selected block is trawled once for 30 minutes. Sampling is usually conducted over three nights.

In addition to the data collected on shrimp, records are also kept on total weight of fish by-catch for each sampling block. Results for March, April and May 99 are presented in Appendixes 3, 4 and 5 respectively. Shrimp to fish by-catch ratio showed wide variation during these months from 1:0.2 (BG74, March 1999) to 1:150 (BL74 & BM73, April 1999).

9. SHRIMP HANDLING, AND PROCESSING

Bahrain shrimp fishing is a one-day operation. All shrimp landed are displayed as a fresh head-on product for local consumption and export. A shrimp auction is conducted daily at the Manama Central Market. Shrimp are usually displayed in 40 kg insulated boxes. The auction is held from 04:00 to 06:00 hrs daily.

During the shrimp season, shrimp are usually displayed as fresh heads-on. During the ban period, only frozen and processed shrimp are allowed for sale. Dried shrimp are sold throughout the year. Demand for dried shrimp increases during the ban period. Shrimp inflow, and wholesale and retail values for 1995 to 1997 are shown in Table 7.

TABLE 7. Shrimp inflow, and wholesale and retail value (in million Bahrain Dinars)
for the years 1995, 1996, and 1997 in Manama Central Market.
(1 US$ = 0.378 Bahrain Dinar)

YEAR	INFLOW (TONNES)	WHOLESALE VALUE	RETAIL VALUE
1995	1,811	2.9	3.4
1996	2,753	3.1	3.8
1997	1,924	2.8	3.4

Source: Fisheries Statistical Section, 1998a

Shrimp wholesale and retail prices showed a decline with increase in landings from 1995 to 1997 (Table 8). Wholesale and retail prices ranged from Bahrain Dinars 1.241/kg to 1.855/kg and from Bahrain Dinars 1.555/kg to 2.157/kg respectively.

YEAR	LANDING (TONNES)	WHOLESALE PRICE	RETAIL PRICE
1995	1,662	1.855	2.157
1996	3,565	1.241	1.555
1997	2,571	1.626	1.891

Source: Fisheries Statistical Section, 1998a

For shrimp exports, frozen products increased between 1995 to 1997 (Table 9). Fresh shrimp were exported in 1995 and 1996. Most of fresh shrimp were exported to Saudi Arabia because of the early opening of Bahrain shrimp season. From the 1997/98 season, the Saudi shrimp fishing season started on the same date as the Bahrain season. This resulted in the saturation of the Saudi market and reduced Bahrain shrimp export. Fresh shrimp were not exported in 1997.

Frozen shrimp exports go y2859ely to the European market. Smaller amounts go to the Near East markets. At present, there are 5 processing plants operating in Bahrain. These plants are capable of producing frozen head-on or headless shrimp for export. Recently, the European Union released new health standards for fish products imported to EU countries. Bahrain shrimp exports are no longer allowed until local regulations are improved and inspection services become available.

Bahrain shrimp cannot be exported to the US markets. This is due to the shrimp import embargo enforced through the US public law 101-162. The law requires that nations or economies that export shrimp to the United States must receive from the department annual certification. There were shrimp exports from Bahrain to US markets in the 1970s, during the operation the BFC. Since that time, there have been no shrimp exports from Bahrain to US.

TABLE 9. Shrimp landings, and wholesale and retail price (in Bahrain Dinars)
for the years 1995, 1996, and 1997 in Manama Central Market

PRODUCT EXPORT/IMPORT	1995	1996	1997
Export – Fresh	164	1,096	-
Export – Frozen	471	856	1,740
Export – Dried	13	-	599
Import – Fresh	89	1	-
Import – Frozen	72	28	50
Import – Dried	36	17	122

Source: Fisheries Statistical Section, 1996, 1997, 1998a.

10. REGULATIONS AND MANAGEMENT MEASURES

The Directorate of Fisheries (Ministry of Works and Agriculture) is the institution concerned with the management of the fisheries resources in Bahrain waters. This office was created by Amiri Decree Number 11 for the year 1979. The first industrial shrimp fleet was established in 1967.

The fishing law was declared in 1981. There have been no major changes to the law since that date. However based on this law, a number of ministerial decrees were issued subsequently to develop management procedures for fisheries resources. Many of these decrees related to the shrimp fishery.

A shrimp ban was first declared in 1980 (decree no. 26 for 1980). This decree set the ban period from 1 March to 30 June 1980, excluding a defined area within the southern ground. Decrees Number 16 and 17 for 1981 required fishing boats to be registered and licensed by the Directorate of Fisheries.

Decree Number 6 for the year 1986 established the minimum mesh sizes for several types of fishing gears used in Bahrain waters. For shrimp trawl, the minimum mesh size was set at 30 mm.

Decree number 15 of the year 1994 prevented issuance of new fishing licenses during 1995 and 1996. Decree Number 16 for the year 1994 required the presence of a Bahrain captain on the fishing boats.

In addition to the above decrees, several decrees were issued annually to set the start and the end of the shrimp seasons.

The current fishing decrees focus on three y2859e area bases for managing Bahrain's shrimp fishery. First is the control of the number and size of fishing boats through a registration and licensing scheme. Second is protecting shrimp recruits by banning shrimp fishing during sensitive time periods. Third is increasing the selectivity of fishing nets by setting a minimum mesh size. Currently, there are no regulations on the use of the by-catch reduction devices (BRD) or turtle excluding devices (TED).

From 1985, the number of shrimp fishing boats has increased dramatically. At present there are about 400 boats ready to be involved in shrimp fishing. As such the licensing scheme has failed to control the fishing effort.

The GCC Fisheries Committee (fourth session, 3-4 October 1996) proposed an expansion of the shrimp fishing ban period to 6 months. The ministerial meeting in November 1996 approved this. For the unique social and economical conditions, Bahrain was excluded from the immediate enforcement of this regulation. In Bahrain the ban period was extended gradually from three to four months only. Further expansion of the ban period received strong opposition from Bahraini fishermen. The GCC countries had great concern about the non-implementation of the six months ban period. This matter will be discussed at a future ministerial meeting.

Bahrain fisheries suffer from inadequate enforcement of fishing regulations (Directorate of Fisheries 1993). This problem was defined as a major obstacle to developemnt of the Bahrain fisheries. In order to establish better control, surveillance, and management, the cabinet issued Decree Number 6 for the year 1997 to create a special committee to address and enforce fishing decrees. This committee includes officials from the Ministry of Works and Agriculture (Directorate of fisheries), Ministry of Information and Cabinet Affairs (television, radio, press), Ministry of Housing, Municipalities, and Environment (Environment Affairs, Municipalities), Ministry of Interior (Coast Guard Directorate), and the Ministry of Labour and Social Affairs.

The Fisheries Enforcement Committee initiated significant surveillance and control efforts during the 1997/98 shrimp ban period. This effort was still not enough to achieve full implementation of shrimp fishing regulations. Illegal shrimp fishing was again reported during the 1999 ban period.

Lower catch rates, longer trawling periods, and smaller shrimp sizes, are all indicators of over-fishing in the Bahrain shrimp fishery. In addition, the shrimp fleet contains a wide size range of boats. This includes small boats, which y2859ely operate on shallow waters, and big boats, which operate in deeper waters. This contracting fishing strategy prevents the proper management of the Bahrain shrimp fishery. The future management requirements should assure that all fishing boats should y2859etain the same fishing strategy. This can be achieved by setting the minimum and maximum size limits of the fishing fleet. This regulation excludes small boats, and consequently prevents catching small shrimp during the season.

To ensure protection of shrimp recruits, a ban area regulation might be considered. This regulation might prevent fishing and other destructive activities in specific areas. These areas should be determined as important shrimp nurseries. However, since enforcement is still inadequate, it would be difficult to secure and protect these sensitive nursery areas.

11. IMPACT OF SHRIMP FISHING ON MARINE ENVIRONMENT

In the case of Bahrain, the impact of shrimp fisheries on the marine environment and living resources have not been studied as a special topic. Several works have been conducted on the fisheries and marine environment. The assessment of impact of shrimp fisheries is based on these works and the opinion of the author.
Shrimp Resources

The common shrimp species P. semisulcatus showed a prolonged spawning behaviour in Bahrain waters (Abdulqader, 1995). This is also suggested by the appearance of shrimp recruits over a long time period. It is common to catch these recruits even during the fishing season by small boats. At present, there is no regulation to protect shallow nursery areas. Trawling in shallow areas may cause over-fishing of recruits. In addition, both Metapenaeus stebbingi and M. kutchensis females spawn in the shallow waters in April and May (Abdulqader, 1999). Fishing during the ban period in these areas will reduce the spawning stocks of these two species.

Shrimp trawlers are causing recruitment over-fishing of the y2859e shrimp species, P. semisulcatus. This is suggested by low catch rates and smaller shrimp sizes observed from the on going GCC shrimp survey. Trawlers are likely to have less impact on the spawning stock of this species.

Ban area regulation may prevent fishing at shrimp nursery grounds. Small boats can be excluded from the shrimping fleet. These could provide further protection to shrimp recruits.

Fish Resources

Results of the first shrimp survey indicated the presence of more than 90 fish species in the shrimp by-catch (Abdulqader, 1986). Based on the occurrence score (see section 8), there were 11 species dominating shrimp by-catch: G. oyena; Paramonachanthus sp.; P. stridens; S. taeniatus; U. tragula; L. lentjan; S. leptolepis; S. canaliculatus; N. bleekeri; R. haffara; and U. sulphureous. The Rabbit fish; S. canaliculatus supports wire trap and gillnet fisheries. It contributed by 16% to the 1997 total fisheries landings. Also L. lentjan, and R. sarba are common species in the wire trap fishery. G. oyena are caught by the gillnet fishery.

The presence of the juveniles of commercially important fish species in the shrimp by-catch indicates an interaction between the shrimp trawls and the wire trap and gillnet fishery.

Shrimp trawls also result in mortality of the non-commercial fish species. This can alter the marine food web. In Bahrain waters shrimping activities are conducted in depths extending from 2 to 20 m. These shallow areas are probably the nursery grounds for many fish species found in Bahrain waters.

Shrimp trawling can reduce fish abundance. In addition to shrimp trawls, there are other fishing practices and gears used which negatively impact the marine environment in Bahrain waters. As such these can also contribute towards reduced fish catch rates. Fish trawlers can contribute in reducing fish catch rates. These trawlers operated in Bahrain waters since the 1970s, and continued to operate until 1998. A 3 month ban period was enforced only in 1997. Now, fish trawling is illegal in Bahrain waters.

Double and triple layered gillnets are illegal in Bahrain waters, but are still used. This non-selective gear is used in shallow and coral reef areas. It catches juvenile fish. The traditional gear, the barrier trap is still used in the coastal waters of Bahrain. If this gear is erected in nursery areas, it can catch large numbers of juvenile fish. Similarly, small mesh gillnets are frequently used to catch small rabbit fish.

Although the impact of shrimp trawls on reducing fish catch rates is considerable, it is difficult to relate this decline solely to shrimp trawlers. Other gear and unhealthy fishing practices also play a role. Increasing net selectivity by adopting BRD will reduce the impact of shrimp trawls on fish resources.

Marine Turtles

In Bahrain waters, turtles are incidentally caught in shrimp trawls. The magnitude of these incidences is difficult to assess especially as turtles are not landed for human consumption. Turtles caught are alive and just usually returned to the sea. The shrimp fishing logbook scheme provided a good opportunity for data collection on turtle incidence in shrimp trawls. Collection of turtle incidence data started with the 1997/98 shrimping season. Results of the 1997/98 season were completed and presented in Abdulqader (draft). Information provided below is based on this work.
.
From the 1997/98 shrimp season, an additional column was introduced into the shrimp fishing logsheet. In this column, fishermen were instructed to note down, on a daily basis, the number of turtles found in their catches. The 'X' symbol was used to indicate turtle absence. Since fishermen only use one local name for sea turtles, it was not possible to differentiate different turtle species.

In the 1997/98 season, there were 1,229 turtle incidences from 54,831 fishing days. Out of the 20 fished areas during the 1997/98 season, turtles were found only in 12 of these grounds (Figures 4 and 13). The "Umudood" area received most of the fishing effort and was the second highest in turtle incidence. The highest turtle incidence was found in "Qumais" fishing area, which had the second highest amount of fishing effort.

Turtles were not found in the western grounds, including Aleslah and Khur Fasht areas (Figures 4 and 13). Turtles were also not found in other areas, including Buoy 25, Jaradah, Mina Sulman, Jaw, Ras Albar, Umalnaisan, and Tibab.

The highest number of turtle incidences and fishing effort were in October 1997 (Figure 14). Turtle incidence declined in the following months and were at the minimum by February 1998 (Figure 14). Fishing effort also shows a similar declining trend during these months but by a smaller magnitude. Turtles were found in the shrimping ground throughout the season.

In Bahrain, there is no regular coastal monitoring of sea turtles stranded. The public usually reports the presence of dead animals to the concerned authority. A few reports on stranded turtles are usually received at different times during a year. If the shrimp fishery is responsible for these mortalities, high numbers of dead turtles should be found during October, when the highest incidence rates occur. Caillouet et al. (1991) detected a significant correlation between stranded turtles and shrimping in the Northwestern Gulf of Mexico shrimp fishery. They concluded that this correlation does not demonstrate that shrimp fishing was the cause of stranded turtles.

Crab

The Bahrain crab fishery is based on a single species, Protunus pelagicus. Crabs are traditionally collected by hand from shallow coastal areas or by the inter-tidal barrier trap. Recently, shrimp trawls (Fisheries Statistical Section 1997, 1998b) produce about 95% of crab landings. Crab landings increased from 1985 to 1997 (Figure 12). By the end of the shrimping season, crab catches usually compensate for the decline in the shrimp catches.

Shrimp trawls operated in shallow waters may catch a considerable amount of juvenile crabs. Intensive operation in these areas may cause recruitment over-fishing. Buried females are usually found in deeper waters. In the GCC shrimp survey, buried females were abundant in March 99. Buried crabs declined gradually in the successive months reaching the lowest percentage in August 99. In Bahrain, present regulations do not ban catching and marketing the buried females. Increase in shrimp fishing effort will likely reduce the number of the buried females. Crab landings (Figure 15) did not indicate that the present level of shrimp fishing caused over-fishing of crab stocks.

Other Fauna

The shovelnose lobster, Thynus orientalis, is common in shrimp by-catch. This species was found in fish trawls in good quantities during the period October to January. Up to almost 200 tonnes of shovelnose were landed in a year (Fisheries Statistics Section 1998a).

The mantis shrimp, Squilla sp., is another crustacean found in shrimp by-catch. This species is not caught in other gears, and does not support any fishery in Bahrain. This species is not consumed locally.

Toward the end of the shrimp season, Cuttlefish Sepia sp., are usually caught in good quantities. Their quantities may surpass shrimp catches during this period. Cuttlefish eggs are usually caught in shrimp by-catches.

Figure 12. Sampling grids defined within the Bahrain waters for the use
of the GCC shrimp survey. The alphanumeric codes are shown per grid.

Figure 14. Total monthly turtle incidences (bars), and total fishing days (square)
during the 1997/98 season, aggregated for all fishing areas

Figure 15. Total crab landings for 1985 to 1997 (Fisheries Statistical Section, 1998a)

Discards from shrimp trawls are used as food by sea gulls and dolphins. Large numbers of sea gulls are usually seen during the fishing season chasing shrimp trawlers. These birds are not found in similar abundance during the ban period. The shrimp provides easy food for both sea gulls and dolphins, and accordingly enhanced their populations.

Bottom Habitat

Shrimp trawls impact the seabed. The direct contact of the gear will damage and destroy algae and sea grass. Also, it can break and remove corals. Operation of the gear generates silt in the water column. Settlement of the silt on coral and other sensitive habitat can suffocate these areas.

12. RESEARCH ACTIVITIES

In this sections only fisheries research activities are highlighted. These include, shrimp trawl selectivity, Spanish mackerel fishery, shrimp fishery, crab fishery, and shovelnose lobster fishery.

Shrimp Trawl Selectivity

Increasing shrimp trawl selectivity is an important solution to minimize fish by-catch. Fish catch rates in Bahrain waters are generally low. Waste from shrimp trawls commercial by-catch may be contributing in decreased fish catch rtaes. The aim of this research was to develop By-catch Reduction Device (BRD) for Bahrain shrimp fishery.

Initial experiments concentrated on evaluating square mesh as a means of reducing fish by-catch (Abdulqader and Mansoor, 1996). These experiments had encouraging results (Appendix 6). There was also a smal reduction in fish by-catch when mamals were in trawl catches.

A rigid grid was developed to exclude big mamals and to facilitate the escape of small fish. The Radius Square Mesh (RSM) was used instead of Square Mesh (SM). Escape areas for small fish and big mamals were covered by collecting bags. All mamals which escaped from the nets were collected in these bags. The prelimanery results of these experiments were encouraging (Table 10).

Further experiments were conducted by covering areas of escape of small fish and big mamals. The aim of these experiments was to set the specification of the Bahrain BRD.

In February 1999 a new research project on BRDs was started. This programme aimed to test the BRD with seasonal variations in fish abundance and change in the physical properties of sea water. This programme will continue until January 2000.

TABLE 10. Species/group, percentage escape in number from the BRD experimented
on 18 August 1997. Numbers in brackets indicates number of species

SPECIES (numbers) / GROUP NAME	% ESCAPED
Lethrinus sp. (3)	15.4
Siganus canaliculatus	71.4
Gerres sp. (3)	30.8
Rhabdosargus haffara	48.9
Upeneus sulphureus	23.2
Nematalosa nasus	11.1
Scomberomorus commerson	12.5
Scolopsis taeniatus	36.8
Alepes melanopetra	63.6
Selar crumenophthalmus	76.5
Arius thalassinus	43.8
Carangidae (7)	38.9
Other sp. (14)	49.0
Sepia sp.	31.6
Protunus pelagicus	1.7

In this study, two trials are conducted each month. Since Bahrain shrimp trawlers use only one net, two commercial boats were required so that catches between the conventional net and a net equipped with the BRD could be compared. Each trial lasted one night. Four 2 hr trawls were normally conducted. Trawls were conducted at 3.5 knots y2859ely in straight line path.

The catch is sorted into shrimp, crab, small fish, big fish (> 30cm total length) and small shrimp (found in abundance in certain months). From the first trawl, carapace length was measured for a random sample of 3 kg of shrimp (only P. semisulcatus) from both boats. Total numbers, and weights of shrimp are recorded for each haul in all boats. Similarly, total number and weight of crab catches are recorded. If total small fish catch is around 40 kg, the entire catch was collected to determine species composition. In cases of higher catches, 30 kg samples were randomly collected. Total weight of small fish was recorded. For big fish, lengths and total weight were recorded for each species. In addition, the presence of sea turtles and any significant remarks were recorded.

Shrimp Fishery

The GCC fisheries committee (fourth session, 3-4 October 1996) recognised the necessity to manage the shrimp resources at a regional level. A standard regional survey was proposed for the collection of the information required for regional shrimp management. This survey was important for countries with a shrimp fishery. These countries include: Bahrain, Kuwait, Saudi Arabia and Qatar.

This survey is conducted monthly for a period of two years. Sampling was started in March 1999. The sea area was divided into 3-mile grids. Each grid is defined by a unique alphanumeric code. Each country is responsible for conducting sampling in their waters.

Within Bahrain waters, 57 fishing blocks were identified for this survey (Figure 12). Each month, about 50-60% of the fishing blocks are randomly selected. Each selected block should be trawled once for 30 minutes. Sampling is usually conducted during three nights.

Different data types are collected during the survey. These include records on the fishing location, towing speed, sampling times, temperature and salinity of the surface and bottom, shrimp weight, fish by-catch weight and weight of small shrimp. Small shrimp are abundant during certain months. In addition, 3 kg shrimp samples were collected from each block. In the laboratory, samples are sorted into species, and further to sex level. Carapace length and maturity stages (in case of females) were recorded for three y2859e species, i.e. P. semisulcatus, P. latisulcatus, and M. kutchensis.

Spanish mackerel fishery

For its migratory behaviour, Spanish mackerel (Scomberomorus commerson) received considerable attention from the GCC fisheries committee. A standard sampling programme was developed, particularly after observing a general decline in landings.

The spanish mackerel programme is based on concurrent sampling of Spanish makerel landed along the whole GCC sea area. This sampling follows standard procedures and practices. The sea area of this programme extends from Kuwait at the Arabain Gulf, across the Gulf of Oman, to Salalah at the Arabian Sea..

The programme proposed that an experimental period shoud precede full adoption of the programme. The experimnetal phase will allow countries to evaluate and amend this programme. This phase lasted for 12 months from November 1997 to October 1998. Along the GCC coasts, 15 landing sites were considered for this programme. The number of sampling sites was determined according to the length of their coastline. One site was determined for Kuwait, Bahrain, and Qatar, two sites in Saudi Arabia, four in UAE, and six in Oman.

At the end of the experimental phase, a regional workshop was organized in Bahrain from 28 November to 2 December 1998. In this workshop, data of the experimental phase were collected and analyzed. Based on these data, the first publication on the GCC Spanish mackerel fisheries was prepared (Abdulqader et al., 1999). This workshop agreed on the extension of this programme to make it continuous or the development of a special computer programme to handle the data of the next phase.

Shovelnose Lobster Fisheries

Shovelnose lobster (Thennus orientalis) is usually found in abundance in fish trawling grounds from October to April. Fish trawlers landed up to 200 tonnes of shovelnose per year (Fisheries Statistical section, 1998a). From 1998 onward, fish trawling was prohibited in Bahrain waters. Besides the long term benefits derived from this regulation, the ban also caused the loss of the shovelnose fishery. The aim of the research on shovelnose was to test the viability of using traps to catch shovelnose lobster. Using traps is not practised in any part of the world.

Five trap designs will be tested under experimental conditions at the National Mariculture Centre (NaMaC). Also different types of bait will be tested. These experiments will start in October 1999.

Crab fishery

Bahrain's crab fishery is now being researched with the co-operation of the Unversity of Wales, UK. This programme will provide a detailed description of crab life cycle in Bahrain waters. This information is essential for management of this fishery. Sampling started in March 1999. It will continue monthly until March 2000. Shrimp trawls, gillnets, and plankton nets are being used to sample different crab life stages in the shallow coastal and offshore deeper areas.

13. PERCEPTION OF THE PRESENT SITUATION REGARDING SHRIMP EXPLOITATION AND ENVIRONMENTAL IMPACTS

This section is based on the findings of the opinion survey (Uwate and Abdulqader, 1999, Appendix C) conducted during the current GEF/UNEP/FAO project. Perception of shrimp fishing and its impact on the environment were documented for different sectors. This includes the views of: 1) the shrimp fishing industry; 2) other fishermen; 3) environmental groups; and 4) fish traders.

Shrimp Fishing Industry

Shrimp fishermen were the y2859e target group of this opinion survey. Shrimp fishermen disagree with 8 problems outlined in the questionnaire. They only agree (70%) that Bahrain shrimp fishery faces a problem of increase in fishing effort. To reduce the fishing effort, they favoured reduction in the number of fishing boats (84%), restrictions on fishing gear (83%), and improvement of the efficiency of fishing gear (78%). They also agree (75%) to change fishing practices to target other species. They did not favour introduction of the BRD (72%), implementing closed area regulations (72%), and the use of another gear in shrimp fishing (75%).

Other Fishermen

Other fishermen considered any reduction in fish by-catch would be beneficial to fish resources. They agreed that the important problems are: catching fish (75%) and shrimp (75%) juveniles, and damaging the seabed (68%). They agree that poor knowledge (62%) and poor management of the shrimp fishery (69%) are fisheries management problems. To reduce the fishing effort, they agreed with 1) improved Monitoring, Control, and Surveillance MCS (91%); 2) restricted fishing in certain season (81%); 3) introducing limitation on fishing gear (72%); 4) implementing closed areas (70%); and 5) reducing the number of fishing boats (68%).

To increase fish and shrimp stocks, they agreed (84, and 86 %) with the introduction of BRDs, and the establishment of closed areas (73, and 84%) respectively. To minimize the damage to the seabed, they agreed with the reduction of bottom contact of shrimp trawls (81%), and replacing trawling with alternative methods (68%).

In order to increase knowledge of the shrimp and fish stocks, 88% of the respondents agreed that more fisheries research was necessary and fishermen should provide more information (72%). To solve poor management, 88% of the responses agree that national priority should be given to fishery research, 79% agreed that the fishing industry and other stakeholders should participate in management decisions.

Environmental groups

The number of respondents from this group was small (6). Responses agreed (83%) that damage to the seabed, poor knowledge on shrimp stocks, and poor management were y2859e fisheries problems. They agree that reducing gear contact (83%), and replace trawling were y2859e issues to minimize damage to the seabed. Most (83%) agreed that increased research on shrimp and fish stocks was needed, and that fishermen should provide more information in order to increase knowledge on shrimp and fish stocks. They agree (83%) that fisheries research should be a higher national priority so fishery management could be improved.

Fish Traders

Fish traders agreed that damage to seabed (80%), poor management (75%), poor knowledge (69%), reduced catch rates (63%), and catching juvenile shrimp (61%) are the significant problems in Bahrain's fisheries. Respondents (81%) indicated that seabed damage could be reduced by decreasing bottom contact of gear, and by replacing trawling with another fishing method. They agree that higher national priority should be given to fishery research and the fishing industry should be involved in management decisions. To increase knowledge on shrimp and fish stocks, all interviewed fish traders agreed that fishery research needs to be increased, and that fishermen should collect more information.

To increase catch rates, 94% agreed that MCS should be improved. Most (89%) agreed to introduce of restrictions on fishing gear, restrict fishing in certain seasons (82%), change target species (77%), and improve gear efficiency (77%). To decrease juvenile shrimp in the catches, 91% agree that size selection devices be introduced, 82% agreed that trawling should be banned when juvenile shrimps were abundant, and 73% agreed that areas be closed when there was a large amount of juvenile shrimp present.

14. NATIONAL IDENTIFICATION OF PRIORITY ISSUES REQUIRING ACTIONS TO MEET ACCEPTABLE STANDARD OF ENVIRONMENTALLY FRIENDLY SHRIMP EXPLOITATION

In Bahrain's fisheries certain preferred species have declining catch rates over a relatively long period. Solving this problem is an objective of fisheries management. Several factors may play a role in this decline and the future plans for the development of fisheries resources should be based on the principle of responsible fishing. At this time there is no official fisheries management plan. Any proposed Bahrain plan for fishery development should give priority to by-catch, unhealthy gear and fishing practices, and the over-fishing problems. These management requirements cannot be implemented in the absence of effective monitoring, control, and surveillance efforts.

Protection of the Nursery Areas

At present, shrimp fishing in Bahrain is not restricted to water of certain depths. Except for the shrimp ban period, fishing can be practised at any time and in any area regardless of the depth. Shrimp fishing causes damage to the marine environment. The magnitude of this damage will vary according to the fishing gear used, and the sensitivity of the area. Shrimp fishing will have greater impact if conducted in shallow waters, which can be nursery grounds for small fish.

Abdulqader and Naylor (1995) suggested that important shrimp nursery areas are found in the shallow water areas south of Fasht Al-Adhom. These waters also may be the spawning ground for M. stebbingi and M. kutchensis (Abdulqader 1999). Therefore, it is important to protect these shallow waters against fishing operations and other human activities. A distance of 1 mile from the coast or from coral reefs may be an appropriate distance.

Protection of the Recruits

At present the shrimp ban period extends for 4 months. It usually starts on 1 April and ends on 1 August. This ban period was implemented to protect shrimp recruits. For proper management, this period should be extended to six months. First September is the ideal date for starting the fishing season. Low catch rates and a high percentage of small shrimp were observed in August catches in 1998 and 1999. Also small shrimp are usually caught in March in shallow waters by small boats. This indicates that during the present fishing season, shrimp recruits are still caught in significant numbers.

To achieve adequate protection of shrimp recruits, it is necessary to extend the shrimp ban period to six months. Both March and August should be included in the ban period. The GCC Fishery Committee also proposed a similar time period for the shrimp ban period.

Stop New Shrimp Fishing Licenses

Over capacity is a major problem in the Bahrain shrimp fishery. The number of fishing boats increased from 26 to about 400 between 1976 and the present time (1999). The increase in the number of fishing boats has resulted in less catch per boat. This is creating difficult economic conditions for these boats. During bad seasons, several boats were unable to continue and were forced to leave the fishery. The present number of boats exceeds the potential of the stock. According to Abdulqader (1995) 73 full time boats are enough for this fishery. The first step toward reducing the number of boats is to stop issuing new shrimp fishing licenses.

Fishing Gear and Boat Limitation

Introduction of winches allowed the use of larger trawl nets. In some cases, nets up to 25 fathoms (foot rope) are used. There is no restriction on the net size used in the shrimp fishery. Similarly, there is no restriction on the size of the shrimp boat.

Bahrain shrimp fishery suffers from extremely high fishing effort and recruitment over-fishing. Any development plan should set 1) an upper size limit for trawl nets, and 2) lower and upper size limits for the shrimp fishing boat.

Increasing Net Mesh Size

Increasing mesh sizes may contribute towards increasing net selectivity. Increasing mesh sizes will also reduce the resistance of the nets during operation. This will be economically beneficial to the fishing boat. The present minimum mesh size (30 mm) is relatively small. For the future, the increase of minimum size to at least 40 mm should considered

Implementation of BRD

The present experiments proved that the use of the BRD in the Bahrain shrimp fishery would be beneficial to the fishery and the marine environment. These benefits need to be highlighted and demonstrated to the fishermen. These benefits included: 1) reducing the sorting time; 2) improving shrimp quality; 3) y2859etaining net efficiency for a longer period; and 4) y2859etaining the bio-diversity of the environment. Demonstrating these benefits will convince fishermen to adopt the BRD.

For successful BRD adoption by shrimp fishermen, it is important that they believe in its importance. They should understand the operation concepts of the BRD and should be able to handle problems arising from use of the device. An extension programme should be initiated to demonstrate the necessity of the device to achieve responsible fishing. Also fishermen need training on how to make the device and how to solve problems that may arise from using it. Training also will be required for the Coast Guards who should focus on legal specifications of BRDs, and procedures to verify these specifications.

ACKNOWLEDGMENTS

I would like to express my gratitude and appreciation to Dr. Roger Uwate Adviser Directorate of Fisheries, for his review to the first draft of this document.

LITERATURE CITED

Abdulqader, E. A. A. 1982. The impact of the close season on the shrimp fishery in Bahrain. In Appendix11, pp. 69-76, in FAO 1982, Assessment of the shrimp stocks of the West Coast of the gulf between Iran and the Arabian Peninsula. FI:DP/RAB/80/015, pp.163.

Abdulqader, E. A. A. 1983. Review of the statistical system adopted by the Directorate of Fisheries (Bahrain), Directorate of Fisheries, Ministry of Commerce and Agriculture, Technical Circular No. 16.

Abdulqader, E.A.A., 1986. Study of by-catch generated by shrimp trawling in Bahrain waters. M.Sc. Thesis, University of Wales, U.K., pp. 98.

Abdulqader, E.A.A., 1988. A trial to introduce a reporting scheme for data collection of the artisanal shrimp fishery in Bahrain. Ministry of Commerce and Agriculture (Bahrain), Directorate of Fisheries, Technical Circular No. 33, pp. 9.

Abdulqader, E.A.A., 1995. Fisheries and aspects of the biology of penaeid shrimps of Bahrain. Ph. D. Thesis, University of Wales, U.K, pp. 195.

Abdulqader, E.A.A. and Naylor, E., 1995. Bionomics and migration patterns of the green tiger prawn, Penaeus semisulcatus De Haan, in Bahrain waters. Fisheries Research, 12:395-407.

Abdulqader, E.A.A. and Mehic, N., 1996. Development of GIS for Bahrain shrimp fisheries management. Sixth International Conference on Computer Theory and Applications, 3-5 September 1996, Alexandria, Egypt, pp. 361-366.

Abdulqader, E.A.A. and Mansoor, J., 1996. Preliminary results of shrimp trawl selectivity experiments in Bahrain. In Yimin Ye and AlMatar, Proceedings of the meetings of the working group on shrimp and other invertebrates and working group on demersal fishes and marine habitat, Kuwait, 11-13 May 1996, pp. 106-110.

Abdulqader, E.A.A., 1999. The role of shallow waters in the life cycle of the Bahrain penaeid shrimps. Estuarine, Coastal and Shelf Sciences, 49 (Supplement A) pp. 115-121.

Abdulqader, E.A.A.; AlMuameri, J.M.; AlMuhammedi, J.S.; Fita, N.E.; AlZaroni, M.A. and AlMubarak, K.A., 1999. Spanish mackerel fisheries in the GCC waters - report on the experimental phase of the standard program to monitor Spanish mackerel landings in the waters of the GCC countries. Bahrain Center for Studies and Research, GCC General Secretary, pp. 45.

Abdulqader, E.A.A. (draft). Turtle incidences in shrimp trawl nets during the 1997/98 shrimp season in Bahrain waters. (Submitted to Asian Journal of Fisheries).

Boerema, L.K. and Job, T.J., 1968.The state of shrimp and fish resources in the gulf between Iran and the Arabian peninsula. IOFC, first session, Italy, 16-12 September 1968, IOFC/68/INF.11, pp.16.

Boerema, L.K., 1969. The shrimp resources in the gulf between Iran and the Arabian Peninsula. FAO Fisheries Circular No. 310, pp. 29.

Caillouet Jr, C.W.; Duronslet, M.J.; Landry Jr.; A.M., Revera, D.B.; Shaver, D.J.; Stanley, K. M.; Heinly, R.W. and Stabenau, E.K., 1991 Sea turtle strandings and shrimp fishing effort in the North-western Gulf of Mexico, 1986-89. Fishery Bulletin, U.S., 89:712-718.

Directorate of Fisheries, 1993. Survey of fishermen in Bahrain. Ministry of Commerce and Agriculture, Bahrain, pp. 27.

FAO, 1978. Fisheries biologist - shrimp - Bahrain - project findings and recommendations. FI:DP/BAH/74/017, pp. 58.

FAO, 1973. Report of the first session of the Indian Ocean Fishery Commission - special working party on stock assessment of shrimp in the Indian Ocean area. FAO Fisheries Reports No. 138, pp. 40.

Fisheries Statistical Section, 1997. Fisheries statistics for the first half of year 1997. Technical CircularNo. 68, Directorate of Fisheries, Ministry of Commerce and Agriculture.

Fisheries Statistical Section, 1998a. Annual statistics report - 1997. Technical Circular No. 70, Directorate of Fisheries, Ministry of Commerce and Agriculture, pp. 90.

Fisheries Statistical Section, 1998b. Fisheries statistics for the second half of year 1997. Technical Circular No. 69, Directorate of Fisheries, Ministry of Commerce and Agriculture.

Uwate, R.; Abdulqader, E.A.A., 1999. Interaction of the Bahrain shrimp trawl fishery with the marine environment: An opinion survey. GEF/UNEP/FAO Project on Reducing the Impact of Tropical Shrimp Trawling Fisheries on Living Marine Resources through the Adoption of Friendly Techniques and Practices, pp. 33.

Appendix 1. Logbook sheet used by the shrimp trawl fishermen to report on their daily operation.
Additional column was added in 1997 to report turtle incidence

Appendix 2. Scientific names and corresponding family or group names of by-catch species
found in shrimp trawl during the first shrimp survey from June 1980 to June 1981

FAMILY / GROUP NAME	SCIENTIFIC NAME
Triacanthidae	Pseudotriacanthus strigilifer (Cantor, 1849)
Lethrinidae	Lethrinus lentjan (Lacepede, 1802)
	L. nebulosus (Forsskal, 1775)
	Lethrinus sp.
Carangidae	Seriolina nigrofasciata (Ruppell, 1829)
	Selaroides leptolepis (Cuyvier, 1833)
	Selar crumenophthamus (Bloch, 1793)
	Scomberoides commersonianus (Lacepede, 1802)
	Trachurus indicus (Nekrasov, 1966)
	Alepes sp.
	Carangoides bajad (Forsskal, 1775)
	Carangoides sp.
	Gnathanodon speciosus (Forskal, 1775)
Gerreidae	Gerres oyena (Forskal, 1775)
	G. filamentosus (Cuvier, 1829)
Tetraodontidae	Chelonodon patoca (Hamilton-Buchanan, 1822)
	Arothron stellatus (Bloch and Schneider, 1801)
Synodontidae	Saurida undosquamis (Richardson, 1848)
	S. tumbil (Bloch, 1795)
	Trachinocephalus myops (Bloch and Schneider, 1801)
Nemipteridae	Scolopsis taeniatus (Ehernberg in Cuvier and Valenciennes, 1830)
	S. ghanam (Forsskal, 1775)
	Nemipterus bleekeri (Day, 1875)
Teraponidae	Terapon puta (Cuvier, 1829)
	T. theraps (Cuvier, 1829)
	Pelates quadrilineatus (Bloch, 1790)
Monacanthidae	Paramonacanthus choirocephalus (Bleeker, 1852)
	Stephanolepis diaspros (Fraser-Brunner, 1940)
Pegasidae	Pegasus natans (Linnaeus, 1766)
	Pegasus sp.
Sparidae	Rhabdosargus haffara (Forsskal, 1775)
	Acanthopagrus bifasciatus (Forsskal, 1775)
	Argyrops spinifer (Forsskal, 1775)
	Diplodus sargus kotschyi (Steindachner, 1876)
	D. noct ((cuvier & Valenciennes)
Apogonidae	Apogon bifasciatus (Ruppell, 1838)
	Cheilodipterus arabicus (Gmelin, 1788)
Ariidae	Arius thalassinus (Ruppell, 1837)
Mullidae	Upeneus sulphureus (Cuvier, 1829)
	U. tragula (Richardson, 1845)
	U. asymetricus (Lachner)
	Parupeneus heptacanthus (Lacepede, 1802)
	Parupeneus sp.
Blennidae	Petroscirtes ancylodon (Ruppell, 1838)
Leiognathidae	Leiognathus equulus (Forsskal, 1775)
	L. bindus (Valenciennes, 1835)
Sillaginidae	Sillago sihama (Forsskal, 1775)
Clupeidae	Nematolosa nasus (Bloch, 1795)
	Sardinella sp.
Bothidae	Pseudorhombus arsius (Hamilton and Buchanan, 1822)
	Bothus pantherinus (Ruppel, 1830)
Scombridae	Scomberomorus commerson (Lacepede, 1802)
	Rastrelliger kanagurta (Cuvier, 1817)
Mugiloididae	Parapercis ??
Platycephalidae	Platycephalus indicus (Linnaeus, 1758)
	P. tuberculata (Cuvier, in Cuvier and Valenciennes, 1829)
Lutjanidae	Lutjanus fulviflammus (Forsskal, 1775)
	L. ehrenbergi (Peters, 1869)
	L. malabaricus (Bloch and Schneider, 1801)
	Lutjanus sp.
Siganidae	Siganus canaliculatus (Park, 1797)
Callionymidae	Callionymus persicus (Regan, 1905)
Pomacanthidae	Pomacanthus maculosus (Forsskal)
Pomacentridae	Dascyllus trimaculatus (Ruppell, 1829)
	Pomacentrus trichourus (Gunther, 1866)
Echeneididae	Echeneis naucrates (Linnaeus, 1758)
Syngnathidae	Hippocampus kuda (Bleeker, 1852)
Labridae	Gastrophysus lunaris (Bloch & Scneider)
Sphyraenidae	Sphyraena obtusata (Cuvier, 1829)
	S. jello (Cuvier, 1829)
	Sphyraena sp.
Gobiidae	Amblygobius albimaculatus (Ruppell, 1930)
	Cryptocentrus lutheri (Klausewitz, 1960)
Plotosidae	Plotosus linatus (Thunberg, 1787)
Soleidae	Euryglossa orientalis (Bloch & Schneider, 1801)
	Aesopia cornuta (Kaup,1858)
	Solea bleekeri (Boulenger, 1898)
Dactylopteridae	Dactyloptena orientalis (Cuvier, 1829)
Scorpaenidae	Apistus carinatus (Bloch & Schneider, 1801)
	Pseudosynanceia melanostigma (Day, 1878)
	Synanceia nana (Eschmyer & Rama Rao, 1973)
Chaetodontidae	Halichores sp.
Serranidae	Epinephelus suillus (Valenciennes in C. & V., 1828)
Batrachoididae	Batrachus grunniens (Linnaeus, 1758)
Rachycentridae	Rachycentron canadus (Linnaeus, 1776)
Engraulidae	Thryssa sp.
Ephippididae	Platax tiera (Forsskal, 1775)
Haemulidae	Pomadasys stridens (Forsskal, 1775)
Sharks & Rays
Crab	Protunus pelagicus
Sand Lobster	Thynus orientalis
Cuttlefish	Sepia sp.
Mantis shrimp	Squilla sp.

Appendix 3. Results from GCC shrimp survey of shrimp catches (kg), fish by-catch weight (kg),
and shrimp to fish by-catch ratio in March 1999 by sampling block

Block Number	Shrimp Catches	Fish By-catch	Ratio Shrimp: by-catch
BC74	4.9	3	1:0.6
BF74	4.3	6	1:1.4
BF75	8.3	5	1:0.6
BG74	19.7	3	1:0.2
BH72	1.9	40	1:21.1
BH74	7.0	2	1:0.3
BI73	2.1	2	1:1.0
BI74	6.5	4	1:0.6
BJ72	1.4	35	1:25.0
BJ75	1.2	-	-
BJ76	0.7	-	-
BK73	3.2	-	-
BK78	6.0	5	1:0.8
BM72	3.6	50	1:13.9
BH82	7.5	5	1:0.7
BI81	0.5	-	-
BI82	6.0	-	-
BI83	4.5	15	1:3.3
BI85	3.5	10	1:2.9
BJ82	7.0	-	-
BJ83	14.1	-	-
BJ71	3.5	40	11.4
BM71	5.5	50	9.1

Appendix 4. Results from GCC shrimp survey of shrimp catches (kg), fish by-catch weight (kg),
and shrimp to fish by-catch ratio in April 1999 by sampling block

Block Number	Shrimp Catches	Fish By-catch	Ratio Shrimp:by-catch
BB72	14.0	20	1:1.4
BC74	1.0	23	1:23
BD75	4.0	18	1: 4.5
BF75	3.0	18	1:6.0
BI72	2.0	20	1:10.0
BI74	2.5	2	1:0.8
BJ72	2.0	12	1:6.0
BJ73	4.0	4	1:1
BJ74	2.0	2	1:1
BJ75	3.0	2	1:0.7
BJ76	3.0	22	1:7.3
BK72	1.5	22	1:14.7
BK76	2.0	125	1:62.5
BK77	2.2	60	1:27.3
BL74	.5	75	1:150.0
BM73	.5	75	1:150.0
BH81	8	20	1:25
BH83	-	-	-
BI82	.5	7	1:14.0
BI83	2.0	15	1:7.5
BI84	.5	7	1:14.0
BJ82	4.0	1	1:0.3
BJ83	1.0	2	1:2.0
BK82	4.0	2	1:0.5

Appendix 5. Results from GCC shrimp survey of shrimp catches (kg), fish by-catch weight (kg),
and shrimp to fish by-catch ratio in May 1999 by sampling block

Block Number	Shrimp Catches	Fish By-catch	Ratio Shrimp:by-catch
BB74	0.5	-	-
BC72	1.2	20	1:16.7
BD75	0.5	30	1:60.0
BE75	3.7	20	1:5.4
BF74	1	20	1:20.0
BG74	0.4	25	1:62.5
BH73	1.2	15	1:12.5
BH74	1.0	2	1:2
BI72	1.5	45	1:30
BI74	3	4	1:1.3
BI75	0.2	7	1:.35.0
BJ72	1	15	1:15.0
BJ74	0.3	15	1:50
BJ76	1.5	30	1:20.0
BK72	1.0	30	1:30.0
BK74	1.5	20	1:13.3
BK75	1.7	45	1:46.5
BK76	2.0	30	1:15.0
BL72	1.0	45	1:45
BH82	2	60	1:30
BH83	0.4	15	1:37.5
BI83	3	30	1:10
BI84	1	15	1:15
BJ82	17	45	1:2.6
BJ84	1.3	10	1:7.7
BK82	15	40	1:2.7
BK83	1.9	10	1:5.3

Appendix 6. Per species, average number of individuals per haul (X) and correspondent standard
deviation (SD) in modified (with square mesh) and normal shrimp trawls

1) Significant different at a = 0.05 and n = 4, N= significant, NS= non significant.
2) y2859ely P. semisulcatus.