Shing, C.C.A.

Aquatic Commons

Shark Fisheries of Trinidad and Tobago:  
A National Plan of Action 
 
CHRISTINE CHAN A. SHING 
Fisheries Division  
Ministry of Agriculture Land and Marine Resources. 
 Port of Spain, Trinidad and Tobago 
Current address: 
Department of Conservation and Fisheries 
Ministry of Natural Resources and Labour 
Tortola, British Virgin Island.s 
 
 
ABSTRACT 
Sharks are valued fisheries resources in Trinidad and Tobago ranking 
fourth in the total estimated landings of the artisanal fishery.  They are caught 
primarily as bycatch of the artisanal gill-net fishery but are landed as by catch 
of almost all other fisheries such as the artisanal pelagic, and demersal hook 
and line fisheries for mackerels and snappers, respectively; the beach seine 
fishery for mackerels and the demersal trawl fishery for penaeid shrimps. 
There is in addition a small-directed fishery targeting largely the Brazilian 
sharpnose, Rhizoprionodon lalandii.  This species is one of the five most 
important species comprising the artisanal landings, which averages about 800 
metric tons per year.   Sharks are also an important component of the landings 
of the small, offshore, semi-industrial pelagic longline fleet for tunas and 
swordfish.  In response to national concerns for the sustainability of shark 
fisheries, Trinidad and Tobago is developing its National Plan of Action for 
Sharks under the Food and Agriculture Organization’s International Plan of 
Action (IPOA) for sharks.  This poster presents some of the elements of the 
plan and associated assessment report, namely description of the fishery, brief 
status of the knowledge of the main species, catch and effort data and the 
major issues for management as required under the IPOA.  
 
KEY WORDS:  Trinidad and Tobago, sharks, National Plan of Action 
 
Piscifactoría de Tiburón de Trinidad y Tobago:  
Un Plan Nacional de Acción 
 
Los tiburones son recursos de piscifactoría valorados en Trinidad y 
Tobago la clasificación de cuarto el en general estimó aterrizajes del piscifac-
toría artisanal. Ellos son agarrados principalmente cuando por - agarran del 
piscifactoría artisanal neto de papada, pero son conseguidos cuando por 
agarran de casi todos otros piscifactoría como el gancho artisanal pelágico y 
profundo y piscifactoría de línea para caballas y castañuelas respectivamente; 
el piscifactoría de jábega de playa para caballas y el piscifactoría de red de 
arrastre profundo para camarones peneid. Hay además un piscifactoría 
pequeño-dirigido que apunta en gran parte el Brasileño sharpnose, Rhizoprio-
Page 206                 57th Gulf and Caribbean Fisheries Institute  
 
nodon lalandii.  Esta especie es una de las cinco especies más importantes que 
comprenden los aterrizajes artisanal, que hace un promedio de aproximada-
mente 800 mt. por año.  Los tiburones son también un componente importante 
de los aterrizajes de la flota pequeña, en el exterior, semiindustrial pelágica 
longline para atunes y pez espada.  En respuesta a preocupaciones nacionales 
por la sostenibilidad de piscifactoría de tiburón, Trinidad y Tobago desarrollan 
su Plan Nacional de la Acción para Tiburones bajo el Alimento y el Plan 
Internacional de la Organización de Agricultura de la Acción (IPOA) para 
tiburones.  Este cartel presenta algunos elementos del plan e informe de 
evaluación asociado, a saber la descripción del piscifactoría, el breve estado 
del conocimiento de las especies principales, agarrar y datos de esfuerzo y las 
cuestiones principales para la dirección como requerido bajo el IPOA. 
 
PALABRAS CLAVES: Trinidad y Tobago, tiburones, Plan Nacional de 
Acción 
 
 
INTRODUCTION 
Consistent with widespread global trends concerned with the management 
and sustainable use of shark resources, several countries are proceeding with 
the analysis of shark fisheries and the development and implementation of 
National Plans of Action as required under the International Plan of Action 
(IPOA) for shark conservation and Management (FAO Website).  The IPOA 
Sharks is the outcome of a global response to promote sustainable use of shark 
resources.  Sharks and their relatives exhibit life history characteristics which 
render them particularly vulnerable to unrestrained exploitation.  In addition, 
there has been a general outcry for the tremendous waste of shark resources 
through the practice of ‘finning’, that is removing the fins of captured sharks 
and discarding the rest of the animal, often alive.  In 2000, FAO elaborated 
precise guidelines for the development and implementation of shark plans and 
assessment reports at the national regional and international levels (FAO 
2000).  
Adherence to the requirements of the IPOA Sharks, as well as preparation 
and implementation of a NPOA, are both voluntary.  However, the IPOA 
Sharks recommends that states adopt a NPOA if their vessels conduct directed 
fisheries for sharks or regularly catch sharks in non-directed fisheries. Stevens 
et al. (2000) notes that by-catch makes up about half of the annual global catch 
of sharks and rays.   
Trinidad and Tobago, located on the continental shelf of northeastern 
South America about eight miles east of Venezuela, is one of the few Carib-
bean island states where sharks are extensively utilized.  Estimated landings of 
shark rank fourth in volume and value of the species landed by the artisanal 
fleet.  There is also some export of large pelagic sharks and shark fins. As in 
most parts of the world, the fishery is principally a by-catch fishery with a very 
limited, seasonal directed component (Shing 1993).  The fishery is being 
analysed and the biological data collected over the period 1985-1986 and 1987, 
and later are being reviewed in the context of a NPOA. 
 
  Shing, C.C. A.  GCFI:57   (2006) Page 207  
 
 
FISHERY DESCRIPTION 
The principal inshore artisanal fishery that catches sharks is the gill net 
fishery for carite Scomberomorus brasiliensis and kingfish S. cavalla.  This 
fishery contributes about 60% of the estimated shark landings (Henry and 
Martin, 1992).  Sharks are also caught incidentally by the beach seine fishery, 
the hook and line (trolling live bait (a la vive) and banking) fishery; the 
demersal longline or palangue fishery, and the semi-industrial pelagic longline 
fishery.  Of the species of sharks identified from the waters of Trinidad and 
Tobago about 15 generally comprise the catch.  
The artisanal vessels involved in the fishery are either wooden, fiberglass, 
or fiberglass coated wooden boats between 6.71m. and 9.14m. in length called 
pirogues.  These vessels are equipped with one or two outboard engines, 
commonly 45 to 75 hp.  All operations are manual (Henry and Martin 1992). 
The semi-industrial vessels are fully equipped for spending up to seven days at 
sea. Gear used is pelagic longlines. 
 
 
DATA COLLECTION 
Catch and effort data for sharks have been collected since 1962 as part of 
the onshore data collection system.  With this system, data are collected at 31% 
of the fish landing sites for 20 random days in the month. Data are subse-
quently raised to account for non-enumerated days and sites.  Data collected 
includes landings and trip details for each vessel.  Trends in the landings and 
standardized effort for some years are examined. These data do not include the 
offshore semi-industrial fleet.  Attempts to record sharks by species is achiev-
ing limited success. 
Biological data on sharks were collected over the period 1985 - 1986 and 
later from 1987 - 1989 with some follow up activities intermittently from 1999 
- 2000.  Samples were obtained largely through a fishery independent survey, 
which sought to mimic the activities of the inshore artisanal, gillnet vessel on 
the north and east coasts where sharks were found to be most prevalent in the 
landings.  However, while the typical artisanal gillnet vessels use gillnets of 
about 4½ in. mesh size, the nets used in the survey were at least 6 inch mesh 
and deployed specifically for sharks.  The species composition of the catch was 
noted and biological data collected on all species caught.  These included sex, 
total length, weight and stomach contents; for females the width of the shell 
gland, reproductive state, presence of eggs or pups in the uterus, sex (where 
possible), and size of pups.  For males data collected were clasper length and 
reproductive state.  Some of these data are summarized here for five species. 
 
 
CATCH AND EFFORT DATA 
Between 1962 and 2002 landings averaged about 800 tons.  Figure 1 
shows estimated landings for this period.  Landings peaked in the late 1970s, 
declined dramatically in these mid-1990s with an increasing trend in 2000s. 
The variations in landings may be typical of a by catch fishery.  It is to be 
noted however that the peaks in the late 1900s early 2000s are lower than 
Page 208                 57th Gulf and Caribbean Fisheries Institute  
 
peaks in previous years.  CPUE data were standardized for some years between 
1972 and 1992 and is shown in Figure 2.  The CPUE peaked in the late 1970s 
declined in the mid-1980s with further increases.  However, as with the 
landings the later peak is at a lower level. 
 
 
Figure 1.   Estimated landings of sharks 1962 - 2002 
 
 
 
Figure 2.  Standardized CPUE (catch per standard boat trip) (Henry and Martin 
1992) 
Estimated Landings 1962-2002
0
500
1000
1500
2000
1960 1970 1980 1990 2000 2010
Years
La
nd
in
gs
 (t
on
ne
Standardized CPUE for some years between 1972 
and 1991
0
5
10
15
20
25
1970 1975 1980 1985 1990 1995
Years
C
PU
E 
(C
at
ch
 p
er
 s
ta
nd
bo
at
 tr
ip
)
  Shing, C.C. A.  GCFI:57   (2006) Page 209  
 
 
SPECIES COMPOSITION OF THE CATCH 
Data from the fishery independent survey collected with respect to the 
fishing grounds on the north and east are presented in Figure 3.  It shows that 
15 species were most common in the catch.  Carcharhinus porosus was most 
abundant followed by Sphyrna tudes and Rhizoprionodon lalandii.  
 
 
Figure 3:  Percentage species composition of the catch (fishery independent 
survey data) 
 
 
SUMMARY: BIOLOGICAL DATA AND FISHERY NOTES 
 
Biological Data   
Table 1 summarises the biological data based on data collected during 
fishery surveys (in bold) and data from the literature in italics for comparison. 
It provides a snapshot of the life history characteristics of the main exploited 
species.  Largely it demonstrates that these species like other chondrichthyians 
have extended gestation periods, whether they are small or large sharks, pro-
duce a limited number of large progeny and are mature at relatively large sizes. 
 
 
Species Composition (%) of the Catch (Survey 
Data)
C. porosus S. tudes S. tiburo C. limbatus
S.lewini S. media C.plumbeus R. porosus
R. lalandii M.higmani C.perezi M. canis
C.acronotus S. mokarran C brevipinna
Page 210                 57th Gulf and Caribbean Fisheries Institute  
 
 
Fishery Notes 
 
Carcharhinus porosus ― The smalltail shark was found to be quite common in 
the landings as well as in the survey catch.  The catch comprised both neonates 
and immature sharks. Neonates were taken in nets set between 10 to 16 
fathoms off the north and east coasts about three to five miles offshore. On the 
north coast particularly in the months of March to May pregnant females of 
this species comprised a substantial part of the catch of this shark from the 
Table 1: Biological data on five species of sharks (*Data in bold is largest 
specimen in the catch, °data is bold is the smallest female with eggs or pups in 
the uteri or smallest male with a calcified clasper; pup length in bold in the 
largest pups observed, Data in italics from Compagno 1984). 
  
Species Gesta-
tion  
Period 
Litter 
Size 
°Age/Size 
(cm)at 
Maturity 
*Max. 
Length 
(cm) 
Max. 
Age 
Size at 
Birth 
  
Carcharhinus 
porosus 
  
9-10 
months 
  
2-7 
  
75-78 
84 
  
  
150 
  
9yrs 
  
31-
40cm 
  
  
C. limbatus 
10-
12mths 
  
  
  
  
1-10           
(4 com-
mon) 
  
  
  
4-6 
4yrs 
135-
180 
120-
190 
106 
140 
255 
  
  
  
  
167 
200 
12yrs 38-72 
  
  
  
  
  
48cm 
  
Sphyrna tudes 
7-9 mths. 
  
7-9 mths 
6-9 
  
6-10 
  
  
765 
150. 
  
152 
118 
  30cm. 
  
29 -30 
Rhizoprionodon 
porosus 
10-11 
  
  
2-6 
  
2-8 
60 
80 
64 
 65 
110 
  
 97 
105 
  31-
39cm. 
34cm 
R. lalandii   
7mths 
1-4cm 
2-4 
40-50cm 
 
56cm 
64cm 
71cm 
  33-34 
32cm 
  Shing, C.C. A.  GCFI:57   (2006) Page 211  
 
inshore artisanal fishery for mackerels.  A preliminary assessment done in 
1992 (Walker 1992) with respect to this species concluded that it was not yet at 
the stage of maximum exploitation.  Complimentary assessments done on the 
target species Scomberomorus brasiliensis concluded that this species was at 
the level of maximum exploitation and management measures were prescribed 
which included an increase in mesh size and increasing use of lines instead of 
gillnets.  
 
C. limbatus ― The blacktip shark is a favoured species.  The inshore artisanal 
catch of blacktips comprise both neonates and adults depending on the fishing 
location (distance from shore).  Beach seine catches have been observed to 
land both neonates and older, immature males and females but at different 
times suggesting that pups may stay in nearshore waters as they develop.  The 
semi-industrial longline fishery also catches mature blacktips. 
 
Sphyrna tudes ― The smalleye also known as a golden hammerhead or 
buttershark has declined in numbers in the landings of the inshore artisanal 
fishery.  This was also evident from a review of the data collected during the 
fishery survey.  
 
Rhizoprionodon lalandii ― The Brazillian sharpnose like the blacktip is also a 
favoured species given cultural predilection for small sharks.  This shark is the 
focus of a small directed fishery on the north coast of Trinidad.  Unfortunately, 
based on observations of individuals most of the catch comprise females 
carrying pups.  A public awareness programme is focused on restricting the 
development of this fishery. 
 
R. porosus ― The Caribbean sharpnose shark has been observed from the 
catches of most fishing gears in the artisanal fishery. Generally an inshore 
species, catches are usually of adult/mature males and females. 
 
 
ISSUES FOR FISHERY MANAGEMENT 
The location, landings and biological and fisheries notes present a number 
of issues for fishery management: 
i) Multispecies nature of the fishery,  
ii) Apparent patchy distribution of species, 
iii) Landings generally bycatch of more lucrative fisheries, 
iv) Inability of field data collectors to reliably record landings by species, 
v) Different life history stages of the same species caught by different 
fisheries., 
vi) Different life history stages of the same species caught by the same 
fishery, 
vii) Females carrying pups found on same fishing ground as target species 
of some fisheries,  
viii) Lack of stock assessments for important coastal species, 
ix) Need for collaboration with neighbouring states (transboundary 
Page 212                 57th Gulf and Caribbean Fisheries Institute  
 
issues), 
x) Shark finning, 
xi) Systematic recording of shark catches from all sources, 
xii) Framework for identification of threatened species, 
xiii) Inappropriate legal framework, 
xiv) Public education awareness, 
xv) Human resource capability for systematic monitoring of sharks, 
xvi) Post harvest practices that contribute to waste of sharks caught, 
xvii)Ecosystem impacts as a consequence of shark fishing (directed 
fishery), 
xviii)Further research on shark fisheries biology, age and growth, diet 
composition and volume of diets contributed by prey species, and 
xix) Systematic collection of trade data on sharks. 
 
 
CONCLUSION 
Much remains to be done to complete the assessment report for sharks. 
The issues identified so far remain to be reviewed and finalized.  The continu-
ing challenge is the multi-species, bycatch nature of the fishery.  However, the 
management measures that have been proposed and in some cases imple-
mented with regard to the gillnet fishery, includes gear modifications and 
promotion of more selective gears.  These will have implications for the 
associated bycatch of sharks. 
Further studies on these species will require regional collaboration at least 
with neighbouring states to ensure compatibility with regard to management 
approaches. 
 
 
ACKNOWLEDGEMENTS 
The Director of Fisheries Ms. Ann Marie Jobity and the staff of the 
Marine Fishery Analysis Unit are thanked for providing, respectively, support 
and assistance for this work.  The assistance of Fisheries Officers Lara 
Ferreira, Louanna Martin and Suzuette Soomai and Mr. Andre Thomas, 
Systems Manager are gratefully acknowledged.  Special thanks is extended to 
Dr. Jose Castro who provided technical assistance with species identification 
and biological studies on sharks, Mr. Terry Walker and the FAO Project Team 
(Mr. Michael Sanders, Team Leader) are gratefully acknowledged for the 
assessment of C. porosus.  Special thanks is extended to Ms. Shannon Gore, 
Marine Biologist at the Conservation and Fisheries Department, British Virgin 
Islands, for her assistance in compiling the poster and providing advice during 
the preparation of the document. 
 
 
LITERATURE CITED 
Castro, Jose I. 1983.  The Sharks of North American Waters. The W.L.Moody 
Jr., Natural History Series 5. Texas: Texas A&M University Press, 
College Station, Texas USA. 
 
  Shing, C.C. A.  GCFI:57   (2006) Page 213  
 
Chan A Shing, C. 1993.  The status of shark resources in Trinidad and Tobago. 
Trinidad and Tobago: Ministry of Agriculture Land and Marine Re-
sources. Fisheries Division Fisheries Internal Report No. 218 pp.  
Compagno, L.J.V. 1984.  FAO Species Catalogue Vol 4. Sharks of the World. 
An Annotated and Illustrated Catalogue of Shark Species Known to Date.  
Part 2 – Carcharhiniformes. UNDP; FAO Species Synopsis Vol.  4  No. 
125. Part 2. FAO, Rome, Italy. 
Food and Agriculture Organization 2000.  FAO Technical Guidelines for 
Responsible Fisheries- Fisheries Management –4 Suppl. 1-1 Conservation 
and  Management of Sharks. FAO, Rome, Italy. 
Food and Agriculture Organization Website. 2002. Implementation of the 
IPOA Sharks. Food and Agriculture Organisation 8th .FAO, Rome, Italy. 
  http://www.fao.org/DOCREP/003/X8692E/x8692e0b.htm 
Henry, C. 1989.  An exploratory shark fishing survey off the east coast of 
Trinidad, draft. Ministry of Food Production and Marine Exploitation. Port 
of Spain, Trinidad and Tobago: FisheriesTechnical Series  No. 3. 40 pp. 
Henry, C. and  L. Martin. 1992.  Preliminary stock assessment for the Carite 
fishery of Trinidad. FAO/UNDP Project TRI/91/001. Technical Report for 
the Establishment of Data Collection Systems and  Assessment of the 
Fisheries Resources. Port of Spain, Trinidad and Tobago. 47 pp. 
Stevens, J.D., R. Bonfil, N.K. Dulvy, and P.A. Walker. 2000.  The effects of 
fishing on sharks, rays and Chimaeras. (Chondrichthyans) and the 
implications  for marine ecosystems.  ICES Journal of  Marine Science 57
(3):476-494. 
Walker, T. I. [undated]. Trinidad and Tobago Shark Stock Assessment Mission 
Report. FAO, Rome, Italy.  22 pp. 
Page 214                 57th Gulf and Caribbean Fisheries Institute  
 
 
 
 
 
 
 
 
 
 
 
 
 
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