5. Fishing experiments

A record of all fishing stations is given in Annex II. The design of the bottom trawl is shown in Annex I.

North coast.

Table 1 shows standardized catch rates by main groups for the bottom trawl stations. “Demersal” includes the families Sciaenidae (croakers), Lutjanidae (snappers), Pomadasiydae (grunts), Serranidae (groupers), and Ariidae (catfish) and “Pelagic”: Clupeids, anchovies, Carangids, mackerels, barracudas and hairtails.

The catch rates off the north coast were as in Survey II in May fairly high ranging up to one tonne per hour for both demersal and pelagic forms. Sharks seem less abundant though than in May. Much of the catch consisted of large sized fish. Table 2 shows the catch rates by families for demersal fish. The croakers dominated with the rather small sized Jamaica weakfish Cynoscion jamaicensis giving nearly 60 per cent of the total croaker catch mainly resulting from one catch which exceeded one tonne per hour. The larger sized whitemouth croaker, Micropogonias furnieri representing 20 per cent of the catch of this family was more evenly distributed. The not very abundant snappers were mostly southern red snapper, Lutjanus purpureus.

Table 1. North coast. Standardized catch rates by main groups, kg/hour.

ST. NO.	DEP.	Demersal	Sharks	Shrimp	Pelagic	Squid	Other
1020	45	12.8	1.8		288.0		17.7
1021	82	365.1	4.6		155.3		47.2
1022	39	110.2	4.0	16.8	60.2	0.9	47.7
1023	39	43.2		26.8	50.1	1.2	39.8
1024	97	16.6	6.7		20.7	0.7	0.8
1025	46	59.6	12.0		130.6	3.2	57.2
1026	76	1235.6	17.0		53.1		48.4
1027	74	29.5	12.9	0.7	218.8	6.0	39.1
1028	33	54.4	7.6	0.0	148.5		51.8
1029	26	204.0	15.8		1008.0		26.8
1030	24	147.6	36.8	2.6	546.4		94.6
1031	43	117.6	5.6	1.1	173.0	1.5	103.3
1034	63	8.4	27.0		209.5	0.8	27.5
1035	36	75.0	11.6		175.5	0.2	9.2
MEAN		177.1	11.6	3.4	231.2	1.0	43.6

Table 2. North coast. Standardized catch rates of demersal fish by families, kg/hour.

ST. NO.	DEP.	Catfish	Croakers	Grunts	Snappers	Groupers	Other
1020	45				12.8		307.5
1021	82		361.7	0.6	2.8		207.1
1022	39		87.6	1.2	20.8	0.6	129.6
1023	39		41.4			1.8	117.9
1024	97				16.6		28.9
1025	46		47.4		12.2		203.0
1026	76		1145.6		88.8	1.2	118.5
1027	74		2.0		26.4	1.1	277.5
1028	33		35.5		18.9		207.9
1029	26	28.4	162.2	13.4			1050.6
1030	24	8.0	135.4	1.6		2.6	680.4
1031	43	4.0	110.6		3.0		284.5
1034	63				8.4		264.8
1035	36		73.0		2.0		196.5
MEAN		2.8	157.3	1.2	15.2	0.5	291.0

Table 3. North coast. Standardized catch rates of pelagic fish by families, kg/hour.

ST. NO.	DEP.	Clupeids	Anchovies	Carangids	Mack. Barr.	Hairtails	Other
1020	45	46.0		237.1	3.4	1.5	32.3
1021	82	10.5		82.8	1.2	60.8	416.9
1022	39	24.6		27.2		9.3	178.7
1023	39			39.9		11.4	109.8
1024	97			7.3	10.0	4.1	24.1
1025	46	18.2		48.4	62.0	5.2	128.8
1026	76	9.0		15.0	11.1	18.0	1301.0
1027	74	48.0		27.8	13.0	136.0	82.2
1028	33	3.0		72.0	73.5		113.9
1029	26	361.3	33.1	559.0	47.0	7.6	246.6
1030	24	228.8	23.4	99.2		195.0	281.6
1031	43	25.0	1.0	137.0	4.0	7.5	227.6
1032	8	28.7	81.5	6.1	3.2	0.8	3.7
1034	63			163.1	6.4	40.8	62.9
1035	36	37.5		104.5	26.5	7.2	95.8
MEAN		56.0	9.2	108.4	17.4	33.6	220.41

Table 3 shows the catch rates by families for the pelagic fish. The Clupeids were medium sized and juvenile forms of dogtooth herring, Chirocentrodon bleekerianus, pellona Pellona harroweri and thread herring Opisthonema oglinum. Moonfish Selene seta pinnis and rough scad Trachurus lathami of generally large size were the most common Carangids. The barracudas were far more abundant than the Spanish mackerels with the guachanche barracuda dominating. The hairtail Trichiurus lepturus was abundant, often with large sized specimens.

Table 4. East coast. Standardized catch rates by main groups, kg/hour.

ST. NO.	DEP.	Demersal	Sharks	Shrimp	Pelagic	Squid	Other
1033	126	8.4			56.9	0.0	23.8
1037	28	450.0	13.0	5.0	44.0		112.6
1038	35	323.2	10.7	1.1	46.8		45.6
1039	28	421.4	17.4	14.0	74.4		50.1
1046	49	8.7	10.0		40.8	5.0	4.0
1047	30	194.2			18.3	0.3	57.3
1048	34	25.1	9.4		42.3	4.0	2.2
1049	30	27.2			47.2	4.8	40.2
1050	61	31.4	31.8	3.6	101.7	2.4	30.7
1051	55	49.4	4.8	9.4	99.7	4.8	40.6
MEAN		153.9	9.7	3.3	57.2	2.1	40.7

East coast.

Table 4 presents the standardized catch rates by main groups of fish for 10 hauls in different parts of the wide eastern shelf. North of the Manzanilla Bank trawlable bottom is limited to a few areas and there is a wide shallow and partly corraline belt inshore. This is the reason for the wide dispersion of the fishing stations in this area. The catch rates are low, approximately as in Survey II. Table 5 shows the demersal fish by families. Part of the croakers were small sized species, but about 25 per cent was whitemouthed croaker, Micropogonias furnieri. The snapper catch at st. 1047 was large sized mostly mutton snapper Lutjanus analis and was taken close to hard inshore bottom. Otherwise lane snapper Lutjanus synagris was most common.

Table 5. East coast. Standardized catch rates of demersal fish by families, kg/hour.

ST. NO.	DEP.	Catfish	Croakers	Grunts	Snappers	Groupers	Other
1033	126				65.3	0.0	23.8
1037	28	64.0	386.0	5.0	44.0		125.6
1038	35	13.2	285.6	2.7	69.6		56.3
1039	28	20.8	368.8	34.8	85.4		67.5
1046	49			0.4	49.1	5.0	14.0
1047	30			2.4	208.4	2.1	57.3
1048	34			23.4	44.0	4.0	11.6
1049	30			3.6	70.0	5.6	40.2
1050	61		14.2	3.6	118.8	2.5	62.5
1051	55	5.4	26.8	9.4	116.5	5.2	45.4
MEAN		10.3	108.1	8.5	87.1	2.4	50.4

East coast deep slope.

Table 6 presents the catch rates for deep water shrimp on the slope off the east coast. In the hauls at 380 and 440 m depth the shrimp catches were about 5 and 11 kg/hour of the gender Penaeopsis and in the four hauls between 670 and 800 m the commercial species was Plesiopenaeus edwardsiensis with catch rates from 1.7 to 3.2 kg/hour. The rates were thus consistently low and below those obtained previously.

Table 6. East coast deep slope. Catch rates for shrimp, kg/hour.

ST. NO.	DEP.	Shrimp	Squid	Sharks	Other
1040	720	8.5	2.00	0.0	33.3
1041	670	4.5	6.50	1.0	31.8
1042	383	5.4	2.70	37.5	3440.1
1043	442	12.4	5.50	0.2	94.4
1044	689	5.3	7.10	2.4	50.6
1045	797	7.0	6.00	0.4	30.8
MEAN		7.1	4.9	6.94	613.5

The large catch offish on station 1042, about 3.5 tonnes consisted nearly exclusively of Ariomma bondi, driftfish.

Joint Fishing Area.

A total of 26 trawl hauls were worked in a special programme to cover the Joint Fishing Area. Some of these were repeat hauls in approximately the same position to study daynight variations in the catch of the various types of fish.

Table 7. Joint Fishing Zone. Standardized catch rates by main groups, kg/hour.

ST. NO.	DEP.	Demersal	Sharks	Shrimp	Pelagic	Squid	Other
1052	36	77.7	1.4	15.7	36.5		78.3
1053	49	102.5	11.0	4.5	21.9		8.4
1054	17	52.2	5.2	6.3	442.8		9.6
1055	43	86.6	4.8	0.2	112.7		27.3
1056	55	280.9	1.2	0.4	93.2	1.5	9.5
1057	32	234.8	32.6		193.2	0.8	35.9
1058	17	71.6	12.3		288.9		59.4
1059	32	64.4	14.8		266.2		35.6
1060	31	80.6	2.5	29.8	71.2	12.0	18.9
1061	14	128.5		26.8	311.4		33.1
1062	19	56.3		14.4	201.4		84.3
1063		15.3	1.3	12.0	130.1		11.5
1064	45	63.9	6.3	1.2	9.9		10.4
1065	19	60.7	1.8	21.4	35.6		22.8
1066	31
1067	37	47.5	13.0		148.0	0.1	21.1
1068	53	106.8	1.2	4.8	96.8	1.2	15.7
1069	40	192.3	1.1	67.2	108.6	1.2	10.5
1070	33	97.8		15.6	29.5		8.4
1071	29	47.9		9.7	32.3		84.4
1072	16	11.6		9.8	60.8	2.4	14.6
1073	17	38.2		31.2	34.0		34.6
1074	37	449.0	5.2	2.0	206.0	0.6	6.0
1075	33	291.1		18.0	65.6	0.7	140.7
1076	36	91.2	1.0	3.2	41.7		21.7
1077	21	137.0		40.0	562.9	24.0	122.4
MEAN		111.0	4.4	12.8	138.5	1.7	35.6

Table 8. Joint Fishing Zone. Standardized catch rates for demersal fish by families, kg/hour.

ST. NO.	DEP.	Catfish	Croakers	Grunts	Snappers	Groupers	Other
1052	36		66.4	2.0	7.7	1.6	132.0
1053	49		92.1	6.0	4.4		45.8
1054	17	2.2	49.4	0.6			463.9
1055	43	12.0	74.2		0.4		145.0
1056	55	22.4	188.4	56.0	14.1		105.8
1057	32		188.0		44.5	2.2	262.5
1058	17	8.5	54.0		2.9	6.2	360.6
1059	32	10.0	40.0		14.0	0.4	316.6
1060	31	22.4	58.2				134.4
1061	14	24.3	104.2				371.4
1062	19		50.0	0.3	6.0		300.1
1063			14.6		0.6		155.0
1064	45	1.5	61.4		1.0		27.9
1065	19	8.4	52.2	0.1			81.7
1067	37		20.3		26.9	0.3	182.3
1068	53	18.6	79.8		8.4		119.8
1069	40	4.8	184.5		3.0		188.7
1070	33	2.2	95.6				53.6
1071	29		26.4		18.9	2.6	126.4
1072	16		11.0		0.1	0.4	87.8
1073	17		37.0		1.2		99.8
1074	37		432.0		13.0	4.0	219.8
1075	33	62.0	220.3	8.8			225.0
1076	36	28.9	62.3				67.7
1077	21	1.1	130.8	5.0			749.3
MEAN		9.1	95.7	3.1	6.6	0.7	200.9

Table 7 lists the standardized catch rates by broad groups for all the prepositioned hauls made. Compared with the two previous surveys in May and in August the catch rates for the broad groups offish are about the same or lower, but there is some increase for shrimp. Of a total catch of 250 kg of the larger Penaeids 50 % was brown shrimp Penaeus subtilis and 35 % pink shrimp P. notialis, the rest red spotted and white. Table 8 shows the catch rates by families of demersal fish. The Jamaica weakfish dominate the croakers with more than 60 %, but whitemouth croaker Micropogonias furnieri also occurred abundantly with often large sized fish. Table 9 presenting the pelagic forms shows Clupeids to be the most common family although catch rates are overall small. As in the Guianas the season seems to be one of recruitment of small pelagic fish with juveniles dominating. The most important Clupeid species were dogtooth herring Chirocentrodon bleekerianus, pellona Pellona harroweri, thread herring Opisthonema oglinum and scaled herring Harengula jaguana. Barracudas and Spanish mackerel were scarce, but hairtails often of large size represented a pelagic predator.

Size distributions of some of the most common forms are shown in Annex 4.

Table 9. Joint Fishing Zone. Standardized catch rates for pelagic fish by families, kg/hour.

ST. NO.	DEP.	Clupeids	Anchovies	Carangids	Barr&Mack	Hairtails	Other
1052	36	3.2	1.1	30.10		2.1	173.1
1053	49	2.7	8.4			10.8	126.4
1054	17	118.0	210.6	11.80	94.0	8.4	73.3
1055	43	67.8	3.5	1.78	1.2	38.4	118.9
1056	55	63.6		1.60		29.5	292.0
1057	32	53.9	48.0		10.9	81.1	303.3
1056	17	46.5	140.3	15.20	12.2	74.6	143.3
1059	32	98.6	128.0	27.60		12.0	114.8
1060	31	42.0	19.2	1.40		20.6	131.8
1061	14	113.8	93.4	1.80		102.4	188.5
1062	19	180.0	9.0		2.4	10.0	155.0
1063		66.5	36.8	2.40	4.0	20.4	40.1
1064	45	0.9	5.6	0.10		3.3	81.9
1065	19	0.9	27.1	1.90		5.7	106.8
1067	37	111.8	2.1	19.60	12.0	2.6	81.6
1068	53	54.4		5.52		38.1	128.5
1069	40	34.8	65.2	3.00		6.7	271.2
1070	33	1.2	23.5			4.8	121.9
1071	29	25.2	0.8	0.32		6.0	142.1
1072	16	15.3	1.9	0.90	2.3	42.8	36.1
1073	17	26.4	2.4	1.20		4.0	104.0
1074	37	87.4	0.6			118.6	462.2
1075	33	16.2	3.6	10.80		35.7	449.8
1076	36	4.9	3.0	2.80		31.0	117.2
1077	21	324.0	111.1	16.22	32.0	103.6	299.4
MEAN		62.4	37.8	6.2	6.8	32.5	170.5