Characterisation of the Commercial Mangrove Land Crab Fishery in Trinidad

CERMES Technical Report No 76

Characterisation of the commercial mangrove land crab fishery in Trinidad

M.E. MAYNARD AND H.A. OXENFORD

Centre for Resource Management and Environmental Studies Faculty of Science and Technology The University of the West Indies Cave Hill Campus, Barbados

2014

ABSTRACT

Mangroves are typically found along coastlines within the tropics. The natural resources encompassed within these mangrove ecosystems provide goods and services which can be of great commercial value to humans. Mangrove land crabs are one such resource. Within the Caribbean region, mangrove land crab harvesting is common though small scale in nature, often not included in countries‟ commercial fisheries reports and with little to no management. As such, these „fisheries‟ are plagued by uncontrolled exploitation and a lack of formal information, as it relates to the status of the resource. The Caribbean island of Trinidad is no exception.

Trinidad is home to two species of mangrove land crab; the blue land crab, Cardisoma guanhumi and the hairy land crab, Ucides cordatus, with both species being harvested and sold commercially. The country of Trinidad and Tobago is either a contracting member or a signatory party to a number of conventions including the Convention on Wetlands of International Importance Especially as Waterfowl Habitat (Ramsar Convention), the Convention on Biodiversity (CBD) and the Protocol concerning Specially Protected Areas and Wildlife to the Cartagena Convention (the SPAW Protocol), with each promoting the sustainable use, monitoring, regulation and or protection of fauna due to their possible value and importance. In an effort to provide baseline information which can help Trinidad better attain the goals and responsibilities stipulated under these conventions, this study seeks to characterise the commercial mangrove land crab fishery in Trinidad for the first time.

Data were collected from 29 crab harvesters and 18 vendors via semi-structured interviews, general observations and informal conversations at their vending sites in public markets or along major roads. Crabs were captured in eight mangrove ecosystems throughout the country with the Caroni swamp, on the western coast of the island, being the largest and most commonly used harvesting site on the island. Bamboo and net traps were the main gear types used for catching blue and hairy crabs respectively, and a typical harvester can catch between 41 - 60 crabs per trip. Crabs were found to range between 56 -92 mm in carapace width and 75 - 350 g in weight. The exact number of crabs caught per trip was generally unknown by the harvesters. Once caught, the crabs are bound alive and either sold singly or in bunches at prices ranging between TT$10-$501, depending on the size of the crab. Crude estimates provided by harvesters and vendors suggest that the amount of crab sold by each harvester or vendor per week can range from anywhere between 0.5 to over 90 kg. The majority, 72% each of harvesters and vendors, rely on this fishery as their main source of income. Women comprise a major part of this fishery, representing a third of the harvesting population and two-thirds of the vendors.

From the sample population of 110 crabs of each species, no statistically significant difference was detected between the weights and carapace widths of blue and hairy land crabs. However, within each species there was a significant difference between the weights of males and females for both blue and hairy crab, and a significant difference observed in the carapace widths of the males and females of blue crabs. This difference in carapace width was not observed between male and female hairy crabs. The weight-width relationships of males and females for each species indicated a pattern of negative allometric growth. The sex ratio was similar for both

1 Exchange rate: US $1= TT $6.42 i species, with male to female ratios being approximately 2:1 for both. Juveniles made up a very small percentage of the sample population, with only seven being found amongst the sampled blue crabs and none amongst the hairy crabs.

Crab harvesting is not only a small scale commercial activity in Trinidad, but is also a popular recreational activity amongst locals during the spawning months of July to September, known as the “running” season. During this time, the crabs are abundant and easy to catch during their trek to and from the sea, where they deposit their eggs. These recreational harvesters, who may also sell a portion of their catch, present competition for regular harvesters and vendors.

Despite the importance of crab harvesting, it remains unregulated and unmonitored, and more than half of the harvesters reported that they have observed a decline in the abundance of the mangrove land crabs in recent years. This observation, coupled with the fact that crabs are particularly targeted during their spawning migrations and that their mangrove habitats are being degraded, suggests that the current practices are unlikely to be sustainable over the long term.

Keywords: blue land crab; Cardisoma guanhumi; hairy land crab; Ucides cordatus; small scale fishery; Trinidad

ACKNOWLEDGEMENTS

We gratefully acknowledge the participation and assistance of all the Trinidad crab harvesters, vendors and key informants who contributed their time and vast knowledge to this study. We also acknowledge Rosemarie Kishore of the Institute of Marine Affairs (IMA) for her inspiration and key role in providing the necessary tools needed to conduct this study. Special thanks are also extended to Hamish Asmath and Bheshem Ramlal of the IMA and the Department of Geomatics Engineering and Land Management at the UWI St. Augustine Campus respectively, for providing GIS data. In-kind contributions are acknowledged from the Institute of Marine Affairs, Trinidad and Tobago.

iii

TABLE OF CONTENTS

ABSTRACT ...... i

ACKNOWLEDGEMENTS ...... iii

1 INTRODUCTION ...... 1

2 RESEARCH AIMS AND OBJECTIVES ...... 3

3 BACKGROUND ...... 3

3.1 Distribution ...... 3

3.2 General biology ...... 4

3.2.1 Blue land crab (Cardisoma guanhumi) ...... 4

3.2.2 Hairy land crab (Ucides cordatus) ...... 6

3.3 Mangrove land crabs in Trinidad and Tobago ...... 7

4 METHODOLOGY ...... 11

4.1 Field Interviews and Observations ...... 11

4.1.1 Crab vending ...... 11

4.1.2 Crab harvesting ...... 12

4.1.3 Geographic Information System (GIS) mapping ...... 12

4.2 Biological measurements ...... 13

4.3 Data analysis ...... 14

5 RESULTS ...... 15

5.1 Harvest sector ...... 15

5.1.1 Profile of a harvester ...... 15

5.1.2 Harvest sites ...... 21

5.1.3 Harvesting methods ...... 21

5.1.4 Harvesting effort ...... 23

5.1.5 Catch per trip ...... 29

5.1.6 Harvesting inputs ...... 30

5.1.7 Factors affecting crab harvesters ...... 32

5.2 Vendors ...... 33

5.2.1 Profile of a Vendor ...... 33

5.2.2 Sources of crab ...... 39

5.3 Retail sector ...... 40

5.3.1 Location ...... 40

5.3.2 Frequency and seasonality ...... 43

5.3.3 The cost of land crabs ...... 44

5.3.4 Sale of land crabs ...... 48

5.3.5 Popularity of each species ...... 49

5.3.6 Quantity of crab sold ...... 51

5.4 The Mangrove land crab resource ...... 52

5.4.1 Size ...... 52

5.4.2 Gender ...... 58

5.4.3 Perceived state of the land crab resource ...... 61

6 DISCUSSION ...... 64

6.1 The fishery ...... 64

6.2 Post harvest and retail ...... 67

6.3 Socio -economic contribution ...... 67

6.4 Management ...... 68

7 CONCLUSION ...... 69

8 REFERENCES ...... 70

9 APPENDICES ...... 75

Appendix 1: Crab vendor survey ...... 75

Appendix 2: Crab harvester survey ...... 78

Appendix 3: Biological data form ...... 82

Appendix 4: Statistical Outputs...... 83

Citation Maynard, M., and H.A. Oxenford 2014. Characterisation of the Commercial Mangrove Land Crab Fishery in Trinidad. Centre for Resource Management and Environmental Studies, The University of the West Indies, Cave Hill Campus, Barbados. CERMES Technical Report No 76. 87 pp. vi

1 INTRODUCTION

Mangroves are commonly found along sheltered coastlines in the tropics and subtropics where they fulfil important socio-economic and environmental functions. These include the provision of a large variety of wood and non-wood forest products, coastal protection against the effects of wind, waves and water currents, conservation of biological diversity, including a number of endangered mammals, reptiles, amphibians and birds, protection of coral reefs, sea-grass beds and shipping lanes against siltation, and provision of habitat, spawning grounds and nutrients for a variety of fish and shellfish, including many commercial species (FAO 2007).

These intertidal mangrove habitats provide a transitional environment between the land and sea, with a diversity and complexity of habitats which is reflected by what Nybakken and Bertness (2005) refer to as the “strange mixture of marine and terrestrial organisms”. Of this “strange mixture”, many of these species are exploited for subsistence and commercial purposes. Commercial species found within mangroves have been described by the Millennium Ecosystem Assessment (2005) as the provisional services of mangroves. Juman (2010) defines these provisional services as being all the goods that can be extracted from wetlands, such as food, freshwater, fibre and fuel and biochemical and genetic materials.

On the Caribbean island of Trinidad, the larger of two islands which constitute the Republic of Trinidad and Tobago, mangroves are a key coastal feature and exploitation of its natural resources is part of the island‟s culture. Mangroves provide many people and households with livelihoods and income particularly at the subsistence level (Juman 2010). Of the myriad of organisms exploited within these mangroves, the capture of crabs, in particular the blue land crab (Cardisoma guanhumi) (Figure 1) and the hairy land crab (Ucides cordatus) (Figure 2), is of commercial importance and constitutes one of the major estuarine fisheries on the island (EMA 1997). These crabs are also believed to play an important ecological role, and are known to have both cultural and recreational importance to Trinidadians. Despite this, the overall importance of the resource has never been assessed, the fishery has never been characterised and data on the crabs and/or crab harvesting are not formally collected by any state agency. As such the mangrove land crab fishery is unmonitored and unregulated with a dearth of formal knowledge on the status of the resource, the stakeholders involved or the key linkages between them. This, coupled with its open access nature (Mangal 2008), means that the land crab resource is at high risk of overexploitation. Amongst other adverse ecological impacts, overexploitation is likely to lead to negative social and economic effects.

Apart from the very limited scope of the 1916 Fisheries Act and the 1970 Marine Areas (Preservation and Enhancement) Act of Trinidad and Tobago, the crab resource remains essentially unmanaged and unprotected. This not only affects the country locally, but also has ramifications internationally as it hinders the achievement of some of the goals stipulated by international agreements to which Trinidad and Tobago is either a contracting member or a signatory party. These include the Convention on Wetlands of International Importance Especially as Waterfowl Habitat (Ramsar Convention), the Convention on Biodiversity (CBD) and the Protocol concerning Specially Protected Areas and Wildlife to the Cartagena Convention (the SPAW Protocol).

This study attempts to address the information gap on the land crab resource and seeks to provide stakeholders and decision makers with an overview of the socio-economic and biological characteristics of the mangrove land crab fishery in Trinidad. It thereby provides baseline information upon which other studies can be conducted and managers can use to make more informed decisions.

Figure 1 General physical features of a typical blue land crab (Cardisoma guanhumi, Latreille, 1828). (Source: Tavares 2002)

Figure 2 General physical features of a typical hairy land crab (Ucides cordatus, Linaeus, 1763). (Source: Tavares 2002)

2 RESEARCH AIMS AND OBJECTIVES

The mangrove land crab fishery in Trinidad is one which is unmanaged, unregulated and unmonitored although it is of social, economic and ecological importance. As such, this study seeks to characterise the extent and nature of this fishery. More specifically, it seeks to provide baseline data on the resources, the people and the practices involved, through the knowledge provided by the main stakeholders involved in the fishery, namely the harvesters and vendors.

The contributions of the harvesters and vendors will be used to determine:

 Who are the active crab fishers and vendors in Trinidad?  The number, range and characteristics of active harvesters and vendors.  How important is crab harvesting and vending as a livelihood?  The location of harvest and vending sites.  What are the average rates of harvest and sale of land crabs?  What are the harvesting and vending practices?  Seasonality within the fishery and factors which may be affecting the fishery and the crab resource.

This resulting information can be used to facilitate informed decision making, proper management decisions and assist more specific research on the fishery in the future.

3 BACKGROUND

3.1 Distribution

The semi-terrestrial land crabs; the blue land crab (Cardisoma guanhumi) and the hairy land crab (Ucides cordatus) are described as being true crabs (Decapoda: Eubrachyura) and are both common to mangrove areas (Tavares 2002). These crabs are distributed (Figure 3 and Figure 4) throughout different ranges within the Western Central Atlantic region only, with the blue land crab having a more extensive distribution, including: Bermuda, southern Florida and Texas, throughout the Caribbean Sea to Brazil (from the states of Ceará to São Paulo) (Figure 3). The distribution of the hairy land crab excludes Bermuda, southern Texas and Central America, although it includes all other territories within which the blue land crab is found and its distribution extends further south along the coast of Brazil to the state of Santa Catarina (Tavares 2002) (Figure 4).

Like their geographic distribution, the habitats of C. guanhumi and U. cordatus also appear to overlap but differ in some respects. The blue land crab is almost completely terrestrial (Burggren and McMahon 1988, Tavares 2002) with burrows, which can be up to 1.5 m deep (Tavares 2002), being made mainly in firm, muddy areas (Kenny 2008, Witherington 2009). Its tolerance for fresh to saltwater conditions allows it to be found as far as 8 km inland from the sea, but always in low lying areas where the water table can be reached so that it can occasionally wet its gills, thereby maintaining gill function and body moisture (Tavares 2002, Witherington 2009). As such they are commonly found amongst mangroves, along canals, or ditches among rocks and debris, open fields, the margins of rivers, in forests, along roads or even under houses (Bright and Hogue 1972, Tavares 2002).

The hairy land crab is said to be a true mangrove crab (Nordhaus 2003) that lives in swamp conditions (Kenny 2008) in burrows of 0.6 to 2.0 m in depth (Goes et al. 2010) that always reach the water table (Tavares 2002). This crab constructs its burrow in very soft mud, either in open ground or under vegetation in areas that are frequently flooded by tidal surge such as; mangroves, along the mouths of rivers and brackish water marshes adjacent to the sea (Bright and Hogue 1972, Tavares 2002) such that when these areas are flooded by the tide these crabs remain within their burrows (Nordhaus 2003). U. cordatus is often found within the burrows of other crab species such as the Cardisoma (Tavares 2002).

Figure 3 Geographic range of the blue land crab (Cardisoma guanhumi) (Source: Tavares 2002)

Figure 4 Geographic range of the hairy land crab (Ucides cordatus) (Source: Tavares 2002)

3.2 General biology

3.2.1 Blue land crab (Cardisoma guanhumi)

The blue land crab belongs to the family Gecarcinidae (land crabs) despite the fact that their life cycle is not completely terrestrial. They are still dependent on the sea during the spawning 4 season (Burggren and McMahon 1988). Although all of the seven species belonging to the Cardisoma genus are distributed throughout the tropics, C. guanhumi is the only one that is located within the Western Central Atlantic region (Burggren and McMahon 1988).

These crabs have a carapace that is broadly egg shaped that narrows to the back and can have a maximum width of 120 mm in males and 110 mm in females (Tavares 2002). They have eyes that are widespread, large and on fairly long stalks and ambulatory or “walking” legs that are sparsely hairy (Gifford 1962, Hill 2001 and Tavares 2002). The chelipeds of these crabs, which are arm-like structures to the front of the ambulatory legs, end in a chelae or pincer, one of which is larger than the other. However, the difference in size between the two pincers is more exaggerated and conspicuous in males than females (Gifford 1962, Tavares 2002).

Colour is a distinguishing factor for this species as it changes with various life stages and according to the sex. Juveniles first appear dark brown with a transitional stage where the carapace is purple and the legs orange (Tavares 2002, Witherington 2009). Adults are generally a bluish-grey colour with dirty white chelipeds (Bright and Hogue 1972) (Figure 5 ) however; females that are ovulating, carrying or bearing eggs, turn almost white or grey (Lutz and Austin 1983, Hill 2001, Tavares 2002).

Figure 5 Typical colouration of an adult blue land crab. (Source: Teixeira 2008)

These crabs reach sexual maturity at around four years of age (Hill 2001, Hostetler et al. 2013). The entire yearly reproductive cycle is synchronised with the patterns of the weather and the lunar cycles. Typically the onset of the “rainy season” in their tropical habitats, which generally extends from June to November, and the nights preceding and following a full moon during this time, instigates peaks of mass spawning (Gifford 1962, Lutz and Austin 1983). The time, place and manner of copulation are said to be unknown. However, it is known that the sperm is carried by the female and the eggs fertilised internally. Once fertilisation occurs, the eggs, which can number 300,000 to 700,000, are carried externally by the specially adapted abdomen of the female for approximately two weeks (Lultz and Austin 1983, Hill 2001 and Hostetler et al. 2013). The gravid females migrate to the sea according to the lunar cycle and release their eggs,

5 which then hatch into swimming larvae. These larvae develop through five larval stages and one post larval stage before becoming juveniles (Lultz and Austin 1983, Witherington 2009).

C. guanhumi is said to be a slow growing species compared to other crabs (Hill 2001, Witherington 2009). The ability to grow, as with most other crab species, is facilitated by the shedding of their exoskeletons in a process known as moulting (Witherington 2009). At the pre- moult stage these crabs retreat to their burrows and seal them until the process is complete. The period within which these crabs moult appears to differ based on climatic factors but generally appears to occur during the winter months starting from the end of November through to April or May (Lultz and Austin 1983). The diet of these crabs is said to be primarily herbivorous, including leaves, berries, flowers, grasses and decaying plant material (Hill 2001, Witherington 2009, Hostetler et al. 2013). They are known to occasionally feed on insects and to exhibit cannibalistic tendencies by feeding on their young (Burggren and McMahon 1988, Hill 2001).

3.2.2 Hairy land crab (Ucides cordatus)

The hairy land crab is currently widely recognised as a member of the family Ocypodidae (ghost crabs) although it was previously classified in the same family as Cardisoma; the Gecarcinidae (Burggren and Mc Mahon 1988). This family is a relatively large one with members that exist worldwide in tropical and sub-tropical regions (Burggren and Mc Mahon 1988).

This species is the largest of the mangrove crabs belonging to this family and is said to be the most sluggish of the land crabs (Tavares 2002, Diele and Koch 2010). It can attain a maximum carapace width of 100 mm (Burggren and McMahon 1988, Tavares 2002). The general shape of the carapace amongst other features is strikingly similar to that of C. guanhumi; however, unlike the blue land crab, the carapace is usually bluish and yellow in certain areas with deep dark coloured grooves on its back (Bright and Hogue 1972, Tavares 2002) (Figure 6). The pincers are uneven in both sexes but the size difference is not as exaggerated as in C. guanhumi (Bright and Hogue 1972, Tavares 2002). The legs of U. cordatus are a distinguishing factor between sexes as this species generally has legs that are red-violet in colour (Bright and Hogue 1972) and they are covered in low, silky grey to almost black hairs which are more pronounced on the legs of males (Bright and Hogue 1972, Tavares 2002).

Figure 6 Typical colouration of an adult hairy land crab. (Source: Government of the State of São Paulo Institute of Fisheries n.d.)

The age at which sexual maturity is attained was estimated by Pinheiro et al. (2005) to be around three years old. The reproductive cycle of U. cordatus follows the general pattern of seasonal spawning which coincides with the start of the rainy season. Spawning activity has been described as a series of “mass mate-searching events” controlled by lunar cycles where mate searching behaviour occurs one or two days after the full or new moon for up to four days (Saint- Paul 2006, Diele and Koch 2010). Like C. guanhumi, the females of this species carry their eggs externally on their abdomen once fertilised. Egg incubation can last between 3.5 to 4 weeks, after which the females release the eggs in conjunction with the spring tides which flood the mangroves (Saint-Paul 2006 and Diele and Koch 2010).

U. cordatus like C. guanhumi is a long lived slow growing species (Diele et al 2010) that can attain a maximum life span exceeding 10 years (Araújo 2006). They grow by moulting throughout their life with a growth rate that decreases with age (Diele and Koch 2010). The diet of this species is solely herbivorous, and almost exclusively reliant on mangrove litter, roots and bark (Nordhaus 2003).

The general life history characteristics of slow growth, large size, k-selected reproductive strategy and use of spawning aggregations by both these species of crab suggests that they are highly vulnerable to overfishing (Diele and Koch 2010)

3.3 Mangrove land crabs in Trinidad and Tobago

The twin island Republic of Trinidad and Tobago are the two most southerly islands in the Caribbean archipelago chain. The country is located between 10°02' to 10°50' North latitude and 60°55' to 61°56' West longitude, with Trinidad being 13 km to the East of Venezuela and Tobago being 32 km off the North East coast of Trinidad (Soomai 2004) (Figure 7 and Figure 8). Tobago is the smaller of the two islands with an area of 300 km2 as compared to its larger sister isle which has an area of 4,828 km2 (FAO 2011). The total coastline of Trinidad and Tobago is 7

362 km and despite sharing certain characteristics, the coastal zones of these islands differ from each other. The coastline of Trinidad is said to be more complex than its sister isle‟s. It is characterised by sandy and rocky beaches, mud flats and extensive mangrove systems while Tobago‟s coastline typically comprises sandy beaches and rocky shorelines although some mangrove forests are present. Mangroves are found along all the coasts of Trinidad with the largest stand, within the Caroni Swamp, representing 60% of the island‟s mangroves. Conversely, in Tobago, they are found mainly on the southwest of the island (FAO 2005). The structural diversity along the coastlines of these islands has allowed for the creation of a number of microhabitats which has allowed for diversity within and amongst species. According to Khan and Ravinchandran (n.d), “Crabs are among the most predominant species in many mangrove forests” and their diversity and or biomass is particularly high within these ecosystems (Nordhaus 2003). Of the variety of species of crabs found within the mangroves of these islands, the blue land crab (Cardisoma guanhumi) and hairy land crab (Ucides cordatus) are the primary species targeted for harvest and sale (Kenny 2008).

These are “two land crabs that are exploited at a high scale and also in an artisanal way in the Caribbean area and on the coasts of Brazil, where populations are endangered due to uncontrolled exploitation” (Carmona-Suarez and Guerra-Castro 2011). According to Mangal (2008), “…the blue land crab (Cardisoma guanhumi) and hairy land crab (Ucides cordatus) are another „open access‟ resource exploited in coastal areas of Trinidad and Tobago. „Crab- catching‟ tends to be an informal activity that may be subsistent in nature with people freely moving into the activity or where those involved have the activity as their sole source of income. Both species are commonly sold along major roadways and in markets as fresh „live‟ specimens and can fetch prices of TT$30 - $502 per kilogram… there is a large number of recreational harvesters that exploit these commodities at times, such as „seasonal‟ crab runs in coastal areas of Trinidad.”

This practice highlighted by Mangal (2008) alludes to the unsustainable way in which many of these crabs are caught within Trinidad and Tobago especially for recreational purposes. The females of both these crab species return to the sea to release their eggs and traditionally it is well known that they can be found “running” to the sea especially when there is a full moon and a high tide. As a result, many people will go to coastal areas on nights like these and capture the “berried” females by the bag-full (EMA 2001) as they make their way to the sea. This will result in loss of potential future populations of these crabs. Crabs are also caught using wooden or bamboo traps which are carefully set and sometimes baited, within the burrows of the targeted crab. The trap is left for a period of time after which the harvester returns to the traps to collect the captured crabs and reset the traps. It has also been reported that the local demand for these crabs is not only being met by the local resources, but is also met by crabs being caught in the Orinoco delta in Venezuela which are illegally sold to fishermen in Trinidad (Carmona-Suarez 2011).

2Exchange rate: US $1= TT $6.42 8

Figure 7 Map showing the location of the islands of Trinidad and Tobago in relation to the Eastern Caribbean and South America (Source: Caribbean Large Marine Ecosystem Project n.d)

Figure 8 The islands of Trinidad and Tobago (Source: Maps101 2013)

The mangrove land crab fishery in Trinidad and Tobago is not only of commercial importance, but it is also important recreationally and culturally as a key component of traditional local dishes such as “crab and callaloo” and the well renowned “curry crab and dumpling” which is especially popular in the island of Tobago. It is said that some Trinidadians go to Tobago simply for this dish and tourists are encouraged to try this local cuisine which can be obtained from many of the island‟s local food vendors and in restaurants. The blue land crab is also used in Tobago for “Crab Races”. These races take place mainly twice per year during the Buccoo Goat Race Festival on the Easter weekend, and the Tobago Heritage Festival in late July, where the crabs are tied with a string which is used to guide them to the finish line, the resulting winner and all the other competitors are then “rewarded” by being used in a pot of curry crab and dumpling (Media and Editorial Projects Limited 2008). These races also attract curious visitors and tourists who wish to witness this unique sport.

Mangal (2008) states that, “The importance of the resource has not been assessed in terms of production, carrying capacity and consumer patterns as an economic venture, in addition, „crab- catching‟ has not been assessed to ascertain the number of people involved in the activity.” A significant resource such as this which contributes to the people of the country of Trinidad and Tobago economically, recreationally and culturally needs to be assessed. There is no formal

10 information on the status of this resource and the associated fishery and as such it is unregulated and unmonitored.

4 METHODOLOGY

4.1 Field Interviews and Observations

Information about the fishery in Trinidad was collected from the crab harvesters and vendors during the months of August to November 2012 through the use of semi-structured questionnaires. Distinct survey instruments were developed for harvesters and vendors and were field tested using the responses of three interviewees to determine the applicability and relevance of the questions and to fine tune the questionnaires before their application throughout the entire research project (Appendix 1 and 2).

As there was no formal information on the fishery, and consequently the people involved, it was determined that the best way to locate and interview the crab harvesters and vendors was via their chosen vending sites. Many harvesters sell the crabs they have captured in the same locations as vendors, and the two can only be distinguished via interview. The location of harvesters and vendors was initially facilitated by information provided by the Institute of Marine Affairs (IMA). This information identified markets such as those found in Port of Spain, San Juan, Tunapuna, Chaguanas, San Fernando etc. and major roadways in areas such as Mayaro, Gasparillo, Caroni etc. as known areas where persons selling crabs could be found. Subsequent harvesters and vendors were located via the snowball sampling method whereby harvesters and vendors were asked to identify other known areas where harvesters and vendors might be found. A few other harvesters and vendors were identified by scoping communities in close proximity to mangroves, and through anecdotal information from members of the public, who were informed about the project and highlighted any sightings of persons selling crab throughout the data collection phase of the project. These sightings were verified with site visits, and once a harvester or vendor was located they were interviewed. If at the time of the site visit there was no one there, the site was revisited at a later date and different time. If the person was still not located then the location was recorded as an “Other Possible Crab Vending Site”, as it was considered to be known that the person sighted at the location was involved in the sale of crabs, but not necessarily the harvest. Questionnaires were supplemented by observations and informal conversations.

The location of the point of sale for each harvester and vendor were noted as part of the questionnaire and their precise locations, including the locations of those who were not interviewed, were recorded using a hand held GARMIN eTrex 10 GPS device in order that they could be located in the future, and to facilitate their inclusion in maps of Trinidad generated in ArcGIS. The total number of crab harvesters and vendors on the island still remains uncertain as none of those interviewed had any idea as to the approximate total number and as such were unable to provide any information regarding this.

4.1.1 Crab vending

The vendor questionnaire contained 29 socio-economic questions in total; 21 related to selling crabs and 8 demographic questions relating to the sex of the interviewee, ethnicity, age group,

11 their community of residence, and the main reason(s) for engaging in this activity, whether this was their main source of income and, if so, how much did selling crab contribute to their overall annual income (Appendix 1).

The crab vending related questions covered topics such as: length of time that they have been selling crabs, the species of crabs which they sell, how they obtained the crabs they sold, the reason for their chosen source of crab, the frequency with which they come out to sell the crabs, the cost which they pay for the crabs and the price for which they sell it, the quantity sold, seasonal availability of the crab and the perceived status of the crab resource and possible reasons for this. Both vendors and harvesters were asked to indicate any other known locations where other harvesters and or vendors could be found.

4.1.2 Crab harvesting

The questionnaire used to interview the harvesters contained 38 questions; 30 questions related to harvesting and selling the crab and 8 questions related to demographics (which were the same as those presented to the vendors). In general the questions which related to selling crab, were the same questions put forward to the vendors although some were modified to relate to their harvesting activities (Appendix 2).

Questions related to harvesting crab incorporated aspects related to; how long they have been catching crab, the location of their chosen harvest sites, the type of crab caught, how and when they are caught and the reasoning behind the chosen method used to capture the crab, the harvest frequency and effort, seasonality in crab harvesting, the perceived status of the crab resource and the possible reasons for its current state.

4.1.3 Geographic Information System (GIS) mapping

ArcGIS version 10.0 software was used to create three different maps representing the Harvester Locations, Vendor Locations and the Proximity of Harvesters‟ Communities in relation to Harvest sites. A shapefile of the “Trinidad_Coastline_1994” (B. Ramlal pers. comm.3) was used to represent the coastline in all three of the maps created.

The general procedure used to create both the Harvester and Vendor Location maps was the same. At each of the locations of all 47 respondents (29 harvesters and 18 vendors) and the 13 “Other Possible Crab Vendors”, waypoints were collected using a handheld GPS device, recording the longitudes and latitudes in decimal degrees. On completion of the data collection process, the waypoints were downloaded from the handheld GPS device and uploaded to the DNRGPS application which allows the user to transfer the data between the handheld GPS device and the ArcGIS Software. The waypoints were characterised based on the location of the interview (either roadside or market) and the interviewee (harvester or vendor) and the DNRGPS application was used to create four separate shapefiles; Market Crab Harvesters, Roadside Crab Harvesters, Market Crab Vendors and Roadside Crab Vendors. A fifth category and shapefile of

3 Personal communication: Dr. Bheshem Ramlal, Head of Department in the Department of Geomatics Engineering and Land Management, University of the West Indies, St. Augustine, Trinidad, phone and e-mail conversation, 14th December, 2012. 12

“Other Possible Crab Vendors” was created to represent those locations where persons were reportedly observed selling crab but were not interviewed.

These shapefiles were opened using the ArcGIS software; ArcMap version 10.0 along with the Trinidad Coastline and a “Roads” of Trinidad and Tobago shapefile (DIVA-GIS n.d.) which was used to represent the major roads in Trinidad, along which harvesters and vendors could be found selling the land crab. The respective layers were turned on or off as needed so as to generate separate maps of the “Harvester Locations” and “Vendor Locations”.

A third map was created to represent the proximity of the harvesters‟ communities of residence to their chosen harvest site, based on the responses of the harvesters to the questions concerning where they caught their crabs, and the general area of which they were resident. This was done again using the “Trinidad_Coastline_1994” shapefile, a shapefile of the “Land Cover” of Trinidad (H. Asmath pers.comm.4) which was used to create a “Mangroves” shapefile and the gazetteer data of locations within Trinidad and Tobago (National Geospatial Intelligence Agency 2012) which was used to create a “Harvester Communities” shapefile.

To create the “Mangroves” shapefile the land cover shapefile was opened in ArcMap and the attribute table was used to highlight all polygons which were classified as “MANGROVES”; the “Export Data” function was then used to create the resultant shapefile using the selected records. The gazetteer data of the locations within Trinidad and Tobago cannot be directly opened in ArcMap and as such it was first viewed in ArcCatalog and the “Export” function was used to create a database file (dbf) where the specific communities listed by the harvesters were selected and the same procedure utilised to create the “Mangroves” shapefile was then used to create the “Harvester Communities” shapefile. Subsequently the mangrove sites were numbered and a legend used to indicate the names of each site and the harvester communities were indicated on the map. All three maps were exported as JPEG files.

4.2 Biological measurements

Permission was obtained from ten different harvesters and vendors to obtain biological data at their vending sites by examining the bundles of crabs which they had on sale. Only the crabs of vendors who purchased them from a local supplier were measured and to ensure that the results would be reflective of the crab resource in Trinidad. All ten gave permission to collect carapace width and gender information, while only five allowed weight measurements. Weight measurements were more difficult to request of harvesters and vendors, as they would have to untie the crabs from bunches for individuals to be weighed accurately. This resulted in the weight, width and gender being recorded for fifty crabs of each species whilst the width and gender of one hundred and ten crabs were recorded for each species.

The biological measurements which were collected included measurement of features such as the width of the carapaces and the weight of the crab. The width of the carapace was recorded to the nearest 0.1 mm, and was measured transversally from the first pair of pereiopods [the largest

4 Personal comm.: Hamish Asmath, Geographic Information Systems Officer, Institute of Marine Affairs, Trinidad e-mail conversation, 21st December, 2012.

13 body dimension of the crab (Alves et al. 2005) (Figure 9)] using a pair of vernier callipers. The weight of the crabs was measured using a kitchen scale and recorded to the nearest 0.5 grams.

Figure 9 Diagram to show where morphometric measurements were taken on the carapace of the land crabs (Source: Alves et al. 2005)

The gender of each of the crabs measured was determined mainly by examining the shape of the abdomen of the crabs to differentiate between males and females (Figure 10). The abdomen of a female crab is broader and rounder to accommodate carrying of eggs, while the shape of the male abdomen is narrow and more pointed than that of a female. In the case of the hairy land crab (Ucides cordatus) the gender of the crab could also be differentiated by observing the amount of hair on the legs of the crab; the female has few, short strands of hair while the males have a mass of long strands of hair on each leg. The legs of the females were further examined to determine whether or not they were carrying eggs at the time of capture.

Figure 10 Differentiation in the general shape of the abdomen of male and female crabs (Source: Tavares 2002)

4.3 Data analysis

All the data collected were recorded and stored in Microsoft Excel spreadsheets and the tabulation and graphical functions were used for analysis. Statistical analyses were performed

14 using SPSS version 21.0. Data to be statistically analysed were first tested for normality using the results of the Sharpiro-Wilk test to determine the nature of data and whether parametric or non-parametric analyses should be conducted. If the data were normal, parametric tests were performed. Otherwise, non-parametric tests were used.

Statistical tests were used to test for significant differences between: the mean weight and carapace width between males and females within species; the mean carapace widths and weights between each species; and the ratio of males to females for each species. Tabulation and graphical functions within Microsoft Excel were used to examine relationships such as: size frequency, mean carapace width, mean weight, width-weight relationships and frequency of juveniles. Sexual maturity was determined using the carapace width of first sexual maturity for males and females as 6.22 cm and 5.87cm respectively in Cardisoma guanhumi (Shinozaki- Mendes et al 2012) and the size of juveniles being less than or equal to 39 mm and 32 mm for male and female Ucides cordatus, respectively (Pinheiro and Hattori 2005).

5 RESULTS

5.1 Harvest sector

5.1.1 Profile of a harvester

Crab harvesters were considered to be those who not only catch but also sell the crabs which they harvest. A total of 29 active crab harvesters were located and interviewed, with eight individuals (28%), of the surveyed population consisting of females. The ethnic backgrounds of the respondents were not diverse and only three groups were represented, with those of East Indian descent being the predominant group representing almost 69% (20 individuals). The remaining 31% consisted of eight individuals of African descent and only one who was of mixed descent between the two (East Indian and African) (Figure 11).

Mixed 3%

African 28%

East Indian 69%

Figure 11 Ethnic backgrounds of the harvesters

Of the six age groupings presented to the harvesters only four of the ascribed categories were utilised. The extreme age group categories (under 20 and over 60) were not selected by any of the respondents. The majority, 31% (nine respondents), fell within the 41- 50 age group while the remainder of respondents were split almost equally amongst the other age groups with seven (24%) or six (21%) each (Figure 12).

9 8 7 6 5 4 3 2 Number Number Respondents of 1 0 Under 20 21-30 31-40 41-50 51-60 Over 60 Age Groups

Figure 12 Age distribution of harvesters

Harvesters were found to live within 17 different communities throughout Trinidad, most of which were located within the western central region of the island. The central community of Felicity has the largest number (eight harvesters, 28%), followed by Las Cuevas, in the north, with four (14%) and the areas of Manzanilla and Sangre Grande, in the east, both having two (7%) each (Figure 13, Table 5.1).

Almost all of the respondents (96%) indicated that they have been catching crabs for more than five years, of which 24% had been doing so for more than 30 years (Figure 14). Persons did not necessarily fall within the same intervals when it came to how long they have been selling crab, with harvesters often reporting that they have been selling crab fewer years than they have been catching crab. However, most (86%) of the respondents had been selling crab for more than five years with 21% doing so for more than 30 years. A male respondent at Claxton Bay was identified as having been involved in the fishery the longest, reporting that he had been catching and selling crabs for the past 50 years while a female respondent interviewed at the Sangre Grande market, who had only started selling and catching crab over the past year, was the newcomer of the group and had the shortest involvement in this activity.

Figure 13 Harvesters‟ residential communities and chosen harvest sites

Table 1 List of harvest sites around Trinidad used by commercial crab harvesters showing their spatial area and the number of known crab harvesters that use them from various communities (Source: Area of harvest sites; Juman 2010)

Harvest site Area of harvest site (ha) No. of harvesters Harvester‟s community

Manzanilla 0.7 2 Manzanilla

1 Arima

1 Sangre Grande

Fishing Pond 269.8 1 Fishing Pond

1 Oropouche

1 Sangre Grande

Caroni Swamp 5263.0 8 Felicity

1 Chaguanas

1 Cunupia

1 Curepe

1 Carapichaima

Las Cuevas 3.0 4 Las Cuevas

Godineau Swamp 765.4 1 San Francique

1 Debe

Nariva Swamp 580.7 1 Mayaro

Claxton Bay 247.8 1 Claxton Bay

1 Marabella

Toco <1.0 1 Toco

Total 7131.3 29

7 6 5 4 Catching 3 Selling 2 1

Number Number Respondents of 0 0-5 6-10 11-15 16-20 21-25 26-30 Over 30 Years

Figure 14 Comparison of crab harvesters‟ involvement in catching and selling crabs

The options of „source of income‟, „tradition‟ or „both‟ were presented to the harvesters as reasons for being involved in the crab fishery. The majority of respondents, 16 individuals (55%), stated that this was simply a source of income for them, while only four (14%) listed tradition as their main reason and the remaining nine respondents (31%) said that it was a mixture of both of these options (Figure 15)

Figure 15 Harvesters‟ reasons for being involved in the crab fishery

Crab harvesting and vending was reported as the main source of income by the majority of harvesters (72%), of which 18 (62%) reported that it contributed to more than 75% of their annual income, while the remaining three (10%) reported that it contributed between 51% - 75% of their annual income. All ten females interviewed fell within the category of having crab harvesting and vending as their main source of income, with nine of them relying on the crab fishery for greater than 75% of their income. The other female within this grouping was also involved in and relied on other mangrove fisheries, such as the oyster and conch fisheries, as sources of income. Of the 18 respondents (62%) that reported crab harvesting and vending as being their main source of income, most of them (15 individuals) indicated that this was their sole source of income (Figure 16).

10% 52%

62% 17%

10%

11%

<25% 26-50% 51-75% >75 Other sources of Income Sole source of Income

Figure 16 Harvesters‟ percentage income derived from the crab fishery

Amongst the 48% that indicated that they also relied on other sources of income, only three alternative sources of employment were listed by harvesters. These included; produce (vegetable or fruit) vending; other fisheries (finfish, oyster and/or conch – later presumed to be Caribbean crown conch, Melongena melongena); and jobs in the public service. The sale of produce was the most common alternative occupation listed by 28% (eight) of respondents and it was often observed during interviews, as being sold by the harvesters simultaneously alongside the crabs. Other fisheries and jobs in the public service were listed by four (14%) and two (7%) respondents, respectively (Figure 17).

Sale of Produce

Other Fisheries

Male

Public Service Female Sources Income of

Crab Fishery Only

0 5 10 15 20 Number of Respondents

Figure 17 Sources of income listed by crab harvesters

5.1.2 Harvest sites

A total of eight harvest sites were recorded, all of which coincided with mangroves along the coasts of the island. The western coast of Trinidad, in particular the Caroni swamp, a designated Ramsar site containing prohibited areas, was the most popular of all the sites with 12 (41%) of the respondents reporting that they harvested in this area, followed by mangroves in Manzanilla on the east coast and Las Cuevas in the north with four (14%) harvesters each. The proximity of the mangroves to their homes appears to have played a role in the choice of harvest site as most, if not all, of the harvesters appear to have chosen the mangroves closest to their communities(Table 1, Figure 13).

All respondents indicated that the blue and hairy land crabs were not found in the same areas within the mangroves and that they had different habitats. Blue land crabs are found further inland in drier areas, such as on the banks, where there is less water and the ground is harder. Conversely the hairy land crabs are found within the mangroves themselves, closer to the coast where there are swampy or muddy conditions; areas that are frequently underwater and the ground is softer.

5.1.3 Harvesting methods

Four different methods were used by the harvesters to catch crabs (Table 2); baited traps which can either be made of bamboo or board (Figure 18), unbaited „traps‟ comprising a bundle of large mesh (4” x 4”) monofilament net staked over the crab hole (Figure 19), wire hooks stuck into the crab hole and/or simply using one‟s hand to take them out of the crab hole or pick them up while they are running. Traps are mainly baited with coconut or some other strong scented or sweet tasting fruit/plant, including pineapple, mango, papaya (Carica papaya), lemon, fig leaves, balisier (Heliconia bihai) leaves or sugarcane. Two of the harvesters reported the creation and use of a “poppy” as bait, which involves either sticking a piece of coconut on a fig leaf stem or wrapping it in a balisier leaf and placing it in the trap or on the trigger of the trap. A type of stifling method which is done only when the tide is low and one can see the crab hole, locally called boché, was also mentioned by one harvester, although she herself did not use it. This apparently involved stuffing crabs‟ holes, which are inundated with water, with mud and grass thereby cutting off the air supply in the hole and making it easier to coax the crab from its hole and capture it.

Of those who set baited traps and unbaited net traps to capture the crab, the basic method used was to collect all of the ensnared crabs into crocus bags before resetting the traps or placing the nets over different holes until the harvesting trip. Those that used hooks or their hands basically went to different holes and pulled the crabs out from them or picked them up while they were running and placed them in crocus bags.

Figure 18 Examples of baited traps, showing (L) a board trap and (R) a bamboo trap. (Source: Mangal 2008 and Maitland 2002)

Figure 19 Example of an unbaited trap, showing (L) the monofilament large mesh net used and (R) demonstrating how it is placed over the entrance of the crab hole by harvestors

The predominant harvest method appeared to differ between the two crab species. All four of the listed methods were employed to catch the blue land crab although baited traps were the most popular with 17 (68%) respondents utilising this method, four (16%) using their hands, three (12%) using nets and only one (4%) using a hook. In the case of the hairy land crab only three of the four methods were utilised with eleven (55%) using nets, six (30%) using their hands, three (15%) using baited traps and none reported using hooks (Figure 20). However, 50% of the harvesters who caught both species of crab used the same method of capture for both types of crab.

10 Blue 8 Hairy Number Number Harvestersof 6

0 Trap Net Hand Hook Harvest Method

Figure 20 Popularity of harvest methods used for each species of crab

A preference for a particular method was stated by 24 (83%) of harvesters as their main reason for choosing a particular method of capture while three (10%) listed tradition and two (7%) stated that their choice was based on the efficiency of the method. Although cost was presented as an option for choosing their method of harvesting, none of them chose this option, with all harvesters indicating that the materials needed, if materials were needed at all, were inexpensive and as such this had no bearing on their decision.

Once the crabs are caught they are tied so as to restrict movement and prevent high rates of mortality which, as harvesters reported, tends to occur if the crabs are left untied as they move continuously and eventually tire themselves out, exerting so much energy in the process that some of them die. This results in the harvester losing a portion of their catch. All harvesters were seen to tie their crab with the same type of plant, which they call “Coré” or “Zore”. This type of grass or reed is apparently found in the mangroves where the crabs are caught. It can be pounded to soften and flatten it before use, or it can be used as is to tie the crabs (Figure 21).

5.1.4 Harvesting effort

The frequency, seasonality and length of harvesting trips and the number of traps set on each trip were used to assess harvesting effort.

Frequency and seasonality

The majority of interviewed harvesters were found to have a consistent, self-imposed, weekly harvesting schedule. However, their schedules differed from one another in the number of days per week that they would actively harvest crabs, varying from daily to just 1-2 days per week, and one of the weekly harvesters did not harvest at all during the March-May moulting season

Figure 21 Examples of the “Coré” or “Zore” mangrove reed used to bind crabs, showing (top) a roll ready for use, (bottom left) blue land crabs tied with the reed in its round state and (bottom right) hairy land crabs tied with the reed in its pounded state or during the annual spawning runs occurring in the months of July, August and September (Table 2). Based on the interviewed population, it appears that harvesting between 3 to 4 days per week was the most popular schedule amongst harvesters with 14 harvesters or 48% of respondents following this pattern. The two harvesters considered here are strictly seasonal, capturing their crabs solely during the “running season” (July to September), with one doing so on a monthly basis and the other opportunistically (Table 2,Figure 22).

Seasonality was found to affect both the harvesting and vending aspects of these crabs for harvesters and was influenced by four main factors; the natural life cycle of the crabs, the lunar cycle, climate, and the cultural and/or religious practices of consumers. The first three can be said to be linked, as the timing of certain major events in the life cycle of the crab, such as spawning, mating and moulting, have been indicated by many of the harvesters as being dependent on certain phases of the moon or the weather pattern being experienced at the time.

Table 2 Crab harvesting methods and effort reported by 29 respondents

Frequency of harvest Number Reported Median Method of Traps Catch per Catch

Un- Baited

set per trip per trip Hook Hand baited Boat Period

Harvest trap trip (# crabs) (# crabs) trap Weekly 61-80 41-60 51 Y Y 1-2 days 81-100 41-60 51 Y 21-40 1 - 20 11 Y 21-40 21-40 31 Y Y Y 21-40 21-40 31 Y 21-40 21-40 31 Y

41-60 21-40 31 Y Y

41-60 21-40 31 Y May)

- 41-60 unsure - Y Y Mar

3-4 days 41-60 unsure - Y Y

61-80 41-60 51 Y Y 81-100 41-60 51 Y Y Y 81-100* 41-60 51 Y Y Y >100 41-60 51 Y Y >100 81-100 91 Y Y Y None unsure - Y 21-40 1- 20 11 Y Y 61-80 41-60 51 Y Y 5-6 days 81-100 unsure - Y Y None 21-40 31 Y 21-40 1- 20 11 Y Y

Year Round (exceptduring moulting period 21-40 1 -20 11 Y 41-60 21-40 31 Y Daily 41-60 21-40 31 Y 41-60 unsure - Y Y 81-100 41-60 51 Y Y Y 81-100 41-60 51 Y

Mean 31

Running Opportunistic None 1- 20 11 Y period only (Jul-Sep) Seasonal Monthly None 81-100 91 Y Y

Mean 57 * This harvester does NOT harvest during the annual „runs‟ which occur during the months of Jul-Sep.

7% 48%

93%

14%

Seasonally Weekly 1-2 Days 3-4 Days 5-6 Days

Figure 22 Harvesting frequency, showing the breakdown of seasonal versus weekly harvesters and the various „categories‟ of weekly harvesters

The vast majority (26 individuals or 90%) of the harvesters reported that they harvest and sell crabs “year round”. Note however, that for a harvester “year round” does not mean all twelve months of the year, but excludes those months during which the crabs close their holes, moult, grow and harden their new shells. This generally spans the months of March to May and according to the harvesters, the crabs become scarce during this time as a result of this activity. Initially the newly formed exoskeleton is soft and can be broken easily. If it breaks a milky white substance is emitted from under the shell. The crab is said to be unpleasant tasting as a result of this substance and the harvesters refrain from catching the crabs as the public does not buy them when they are in this state. Once the transition is complete, and the shells harden, regular harvesters resume catching the crab and continue to do so throughout the rest of the year.

The harvesting and vending patterns of the two strictly seasonal harvesters were solely dependent upon the annual spawning or “running” season which was generally conveyed by the interviewed harvesters as spanning the months of July to September. The running season occurs when the female crabs that are laden with fertilised eggs run towards the sea so as to wash off and deposit the eggs in the water, where the eggs will hatch and develop before returning to land as juveniles. Harvesters reported that there are three major “runs” which occur over the space of three days after the new or full moon for three months. During this time hundreds of crabs make the trek to and back from the shore. This activity in Trinidad attracts large numbers of the general public (not considered harvesters) as the crabs are easy to catch by hand while they are running. One harvester who lived within walking distance of a harvest site reported that often he is only alerted to the fact that the crabs are running due to the noise, traffic and number of people catching the running crabs outside of his home.

The seasonal harvesters were found to be opportunistic, only catching and selling crab during the “running” season. The weekly harvester who refrains from harvesting and selling crab during the “running” season (Table 2) stated the reason for this choice was that it was unprofitable to harvest during runs because of the large number of recreational harvesters who bombarded the market, opportunistically selling their excess catch. This sentiment was echoed by all other regular harvesters who found it more difficult and unprofitable to ply their trade during this season as a result of the competition from recreational harvesters, but despite this, they still continued to catch and sell their crab albeit at a lower price.

Although it appears that the behaviour of recreational harvesters during the “running” season causes financial problems for harvesters, the majority (14 harvesters or 48%) still stated that this season was the best time of the year to catch these crabs due to the ease and abundance while conversely five harvesters (17%) stated that the best time of the year to catch crab was outside of the “running” season. The remaining 35% either stated that after the moulting season was their preferred time or that there was no time of the year which was better for catching crab Figure 23().

6 Number Number Harvestersof 4

0 During running Outside running After moulting season No season in season season particular Season

Figure 23 Best times of the year to catch land crabs according to interviewed crab harvesters

Length of trips

A harvesting trip was defined by the harvesters who set traps, as the time they spent collecting the crab which were caught by the traps which were set on a previous trip and resetting the traps, while for those who used their hands and or hooks as their harvesting method of choice, it simply included the time they spent collecting the crabs. The reported times spent on each trip ranged from less than an hour up to whole day trips with more than 50% of the harvesters reporting that they spent more than a few hours on each trip, with 10 (35%) spending half a day in the field and eight (28%) utilising the entire day (Figure 24).

4 Number Number Harvestersof 2

0 <1 hour 1-2 hours 2-3 hours 3-4 hours 4-5 hours Half Day Whole Day

Time

Figure 24 Length of time spent on crab harvesting trips

Traps set

Of the twenty-five harvesters who chose to set traps as their harvesting method (whether board, bamboo or nets), each reported a different number of traps per trip. As such these figures were combined to create six different categories reflecting a possible range of traps set; 1-20, 21-40, 41-60, 61-80, 81-100 and over 100 (Table 2 and Figure 25). None of these harvesters set less than 20 traps while the majority (15 harvesters or 52%) set between 21-40 or 41-60 traps per trip while two harvesters stated that they set more than 100 traps per trip (Figure 5.15).

7 6 5 4

Number Number Harvestersof 3 2 1 0 1-20 21-40 41-60 61-80 81-100 > 100 Number of Traps

Figure 25 Number of traps set per trip by crab harvesters

5.1.5 Catch per trip

It was revealed that all the harvesters did not keep track of or record the number of crabs they caught on each trip and as such five harvesters (17%) were unable to make any estimations as to the number of crabs they caught per trip. The remaining 24 (83%) were able to provide estimates which were combined into groupings of twenty, viz. 1-20, 21-40, 41-60, 61-80 and 81-100 (Figure 26).

10 9

8 7 6 5 4 3

Number Number ofrespondents 2 1 0 1-20 21-40 41-60 61-80 81-100 Unsure

Amount of crab

Figure 26 Amount of crabs caught per trip

5.1.6 Harvesting inputs

Other than the effort placed into the actual harvesting of crabs, inputs such as transport, monetary expenses and extra labour were also found to be necessary for some harvesters to function within the mangrove land crab fishery.

Transportation

The majority of harvesters (19 respondents or 66%) relied on some form of transport to access their harvest sites of choice. This 66% comprised 13 harvesters (45%), who used a boat, either a pirogue or flat bottom boat, and six (21%) who used some other form of transport such as a personal vehicle or public transportation to access their chosen sites. The harvesters who utilised boats to access their harvest sites consisted of all 12 of those who caught their crab in the Caroni Swamp and one that harvested at the mangroves at Claxton Bay. The remaining 10 (34%) harvesters lived within walking distance of their chosen harvest sites and as such, they required no form of transport (Figure 27).

Walking 34%

Use of a Boat 45%

Other 21%

Figure 27 Use of transportation by the crab harvesters to access harvest sites

Cost of harvesting

All harvesters were of the view that being involved in crab harvesting required little to no financial inputs with the exception of transportation. Materials needed to catch crab were either inexpensive or naturally occurring for example traps that were created out of bamboo. The need for and the type of transportation dictated the amount of money that needed to be spent. Those who lived within walking distance of their chosen harvest sites required no form of transport and no financial inputs were required while those who required a boat to reach their harvest sites reported the highest financial inputs, in the form of money for fuel for the boat, with most, eight of those who use a boat stating that the cost was TT$100 per trip, while the other boat users quoted figures of TT$40 or between TT$150 and $200 per trip (Figure 28). Of the 18 harvesters 30 who spent either half day or the whole day on each of their harvesting trips 16 (89%) of these required either a boat or some other form of transport to reach their harvest site of choice.

Those who used other forms of transport reported figures of TT$10, $30, $40 or $50 per trip with the cost of each trip possibly being dependent on the distance travelled, the form of transport taken and the number of people on the trip. For example the harvester who reported that each trip cost TT$10 lived relatively close to the harvest site, went alone and used public transport, while the harvester who reported a cost of TT$50 lived further away from the harvest site and chose to hire a vehicle to carry her and her family on each trip.

10 $150- $200 8 $100

6 $10- $50 Number Number Respondents of 4 $0

0 Walking Boat Public/Private transportation Type of Transport

Figure 28 Types and cost of transportation used by harvesters

Labour

Most harvesters were accompanied on their trips by either family (34%) or friends (21%). The remaining 13 harvesters (45%) who chose to harvest alone, included all 10 harvesters who lived within walking distance of their destination (Figure 29).

Friends 21%

Alone 45%

Family 34%

Figure 29 Labour used on harvesters‟ trips

5.1.7 Factors affecting crab harvesters

Conversations with harvesters revealed that they experienced the effects of various issues while harvesting often resulting in the depletion of the amount of crab which they catch. These issues can be categorised as being natural and man-made. Of the natural factors, harvesters highlighted the loss of some of their harvest to predators; such as dogs and also the crab-eating raccoon (Procyon cancrivorus) which are found within the mangroves of Trinidad. The occurrence of high tide also affected their harvesting patterns and ability to reach their area of harvest sometimes resulting in them turning back and abandoning a trip. Of the manmade factors most spoke about the effect of recreational harvesters, overexploitation and mangrove degradation (which will be further discussed in a later section), praedial larceny, whereby persons entering the mangrove would steal crab from the traps set by harvesters, and the influx of illegally imported crab from Venezuela. Although none of the harvesters or vendors indicated that they were selling illegally acquired crab, often times if a harvester and or vendor were selling in close proximity one or the other would indicate that the other was selling crab from Venezuela, claims which could not be verified without the cooperation of the harvester or vendor themselves. Harvesters said that the importation of these crabs from Venezuela affected them somewhat negatively as the crab coming from that country were much bigger in size compared to those originating in Trinidad and as such they believed that customers now had unrealistic expectations by thinking that all the crab should be that size and would in turn buy the illegally imported crab as opposed to the local crab.

5.2 Vendors

5.2.1 Profile of a Vendor

Unlike the crab harvesters, vendors only sold crabs and were not involved in the harvesting process in any way. Other than the 29 harvesters, a total of 18 active crab vendors were found and interviewed. Two thirds (12 vendors, 67%) of the interviewed population were female. The ethnic backgrounds of the vendors were also not diverse and only three groups were represented; with those of East Indian descent being the predominant group representing almost 72% (13 individuals) while the remaining 22% consisted of 4 individuals of African descent and only one who was of mixed descent (East Indian and African) (Figure 30).

Mixed 6%

African 22%

East Indian 72%

Figure 30 Ethnic backgrounds of vendors

Of the six age groupings, only the four older categories were chosen by the vendors indicating an older age range than the harvesters. More than half (10 vendors or 56%), fell within the 41- 50 age group while the remaining eight vendors were split three (17%), four (22%) and one (6%) amongst the 31-40, 51-60 and over 60 age groups, respectively (Figure 31)

4 Number Number Vendorsof

0 Under 20 21-30 31-40 41-50 51-60 Over 60 Age Groups

Figure 31 Age distribution of vendors

Vendors were found to reside within 16 different communities, which meant that they were more dispersed throughout the island as compared to harvesters. Almost every vendor was found to reside within a different community, with the exception of three who came from Arima in the north of the island (Figure 32). Vendors‟ communities of residence were found to be in close proximity to their chosen vending locations and were not dependent on the point of origin of the crabs, as was the trend noticed for crab harvesters (Figure 32 and Table 3).

Two thirds (67% or 12 vendors) of the respondents indicated that they had been selling crab for more than fifteen years with the remaining six had been selling crab between 0-10 years, with no respondents falling within the category of selling crab for the past 10-15 years (Figure 33). Two females indicated that they had been selling crab for over 30 years.

The options of „source of income‟, „tradition‟ or „both‟ were presented to the vendors as reasons for being involved in the crab fishery. The majority of respondents, 13 individuals (72%), stated that this was simply a source of income for them, while only three (17%) listed tradition as their main reason and the remaining 2 respondents (11%) said that it was a mixture of both of these options (Figure 34)

Table 3 List of vending locations in relation to vendors‟ residential communities

Vendor Locations Number of Vendors Vendor Community

Arima 2 Arima

Chaguanas 1 Felicity

Couva 1 Carapichaima

1 Couva

Marabella 1 Marabella

Penal 1 Penal

Port of Spain 1 Arima

1 Cunupia

1 Diego Martin

Princes Town 1 Moruga

San Fernando 1 La Romain

1 Princes Town

Sangre Grande 1 Mayaro

1 Toco

San Juan 1 St. James

Tunapuna 1 Sangre Grande

Union Hall 1 Rousillac

Figure 32 Vendors‟ residential communities in relation to their chosen vending sites

Number Number Vendorsof 2

0 0-5 5-10 10-15 15-20 20-25 25-30 Over 30 Years

Figure 33 Vendors‟ involvement in the crab fishery

Figure 34 Vendors‟ reasons for being involved in the crab fishery

The same percentage of vendors as harvesters (72%) indicated that crab vending was their main source of income, of this, 11 vendors (85%) reported that it contributed to more than 75% of their annual income, while the other two (15%) indicating that it contributed between 51% - 75% of their annual income. Crab vending was not only the main source of income but also the sole source of income for 10 (56%) of vendors with the other vendors being involved in finfish fishing and the sale of produce (Figure 35 and Figure 36)

11% 56%

11% 61%

5% 17%

<25% 26-50% 51-75% >75 Other sources of Income Sole source of Income

Figure 35 Vendors‟ percentage income derived from the crab fishery

As for harvesters, the sale of produce was the most common alternative source of income for vendors. Produce was listed by seven (39%) vendors as their alternative source of income, with only one vendor (6%) relying on the finfish fishery (Figure 36).

Sale of Produce

Other Fisheries

Male

Public Service Female Sources Income of

Crab Vendors Only

0 2 4 6 8 10 12 Number of Respondents

Figure 36 Sources of income listed by crab vendors shown separately by gender

5.2.2 Sources of crab

Local or imported

Vendors were asked whether their crab was obtained locally, imported or from both of these sources. Vendors‟ responses revealed that 94% (17 vendors) of them relied solely on local harvesters as their crab source while only one relied on importing the crab. Each vendor was asked to state the reason for choosing this particular source and five different reasons were provided; ease, preference, taste, long lasting and cost. The first four reasons were provided by those who obtained crab locally with the ease of obtaining crab from local harvesters being the most popular reason amongst vendors as it simply involved going to a local harvester and buying the crab from them while importing would involve a longer waiting period, additional costs to import and various other aspects to consider. Vendors also believed that local crab tasted better than the imported crab and that were they to import the crab, they would lose part of their imported stock as they stated that the long trips often resulted in high mortality rates. Conversely, the lone vendor who imported her crab, did so from Grenada and stated that importing the crab from Grenada worked out to be cheaper and was more convenient for her (Figure 37).

8 Imported 6 Local

Number Number Vendorsof 4

0 Ease Preference Taste Long Lasting Cost Reason for chosen crab source

Figure 37 Vendors‟ reasons for their chosen crab source

Seasonal availability

As harvesters were asked to indicate the seasonality of the harvesting of the crab, vendors were asked to indicate whether or not they had noticed an annual pattern in the seasonal availability of the crab, and what factors they had attributed the cause of these changes to. Vendors‟ responses were reflective of the patterns of seasonality which the harvesters experienced with responses indicating that there is greater abundance and availability of crab during the rainy and running seasons and scarcity experienced during the Christmas and moulting seasons. Of the 18 vendors

39 however, six (33%) indicated that although they had noticed a pattern of changing availability throughout the year, they were unsure as to why this occurred.

Source price

The need for vendors to utilise a local or foreign source to obtain their crab meant that they also had to pay for these crabs before they themselves could sell them. Vendors‟ prices were grouped into four different price ranges of TT$5-10, $10-15, $15-20 and $20-25. The majority of vendors (eight or 44%) obtained their crab for between TT$10-15 which included the vendor who imported her crab. Only one vendor fell within the highest price grouping of TTD $20-25 (Figure 38).

4 Imported Local 3

Number Number respondentsof 2

0 5-10 10-15 15-20 20-25 Trinidad and Tobago Dollars

Figure 38 The price paid per pound by vendors for land crabs.

5.3 Retail sector

5.3.1 Location

Crab harvesters and vendors are both involved in the retail sector of the crab fishery and thus they were all located via their vending locations throughout the island.

Generally, they were found to ply their trade to individual customers within „regional‟ public markets, often run by the local government, or from semi-permanent stalls or structures along major roads (Figure 39), which may even lie directly in front of their homes.

Figure 39 Crab vending locations in Trinidad (L) A typical public market and (R) A semi-permanent structure along the roadside

The 29 interviewed harvesters sold their crabs in 18 different general areas, with the majority being located within the western central region of the island in areas such as Caroni, Kelly Village, Chaguanas and Charlieville (Figure 40). The interviewed vendors were found in 12 different general areas, the majority of which were also found on the western side of the island.

Seventeen harvesters (59%) indicated roadside stalls as their primary vending location, followed by 11 (38%) utilising markets and only one (3%) of the harvesters reporting that he sells his harvest solely and directly to a restaurant (Figure 41). Secondary alternative vending locations were also listed by twelve (41%) of the harvesters in the event that they did not sell all of their catch at their primary location. Of the eleven market harvesters three listed other markets while two resorted to roadways, while of the roadside harvesters, four listed markets while two used other major roads and only one stated that they would act as a hawker, driving around to sell the crab (Figure 41). Conversely, vendors appeared to greatly favour markets with 16 (89%) utilising these as their primary vending location. They also rarely utilised secondary locations with only two of the market vendors utilising either another market or roadside location as their secondary location (Figure 41)

Most of the harvesters and vendors interviewed were able to name locations where other harvesters and/ or vendors could be found. Subsequently, this information was used to locate most of the interviewed population and it also provided the locations of other possible vending sites throughout the island, which were included on the map (Figure 40). The number of crab vending sites around the country was thus estimated at 37. However, the total number of crab harvesters and vendors remains uncertain.

Figure 40 Vending locations throughout Trinidad

10 Other Markets 8 Other Roads 6

Number Number Respondents of 4 Single Location

0 Harvester Vendor Harvester Vendor Harvester Vendor Roadside Markets Restaurant

Primary Vending Locations

Figure 41 Harvesters‟ and vendors‟ primary vending locations also showing the number of respondents in each group who had additional alternative vending locations

5.3.2 Frequency and seasonality

Most harvesters (90%) and vendors (89%) stated that they sold crab “year round” with harvesters‟ vending patterns being reflective of their harvesting patterns (Figure 42). With respect to vendors, only two did not sell crab year round and this was because they were both seasonal vendors, with one vending solely during the rainy season and the other doing so three to four times for the year.

Vendors

Seasonal Year Round Harvesters

0 5 10 15 20 25 30 Number of respondents

Figure 42 Vending patterns of harvesters and vendors

Harvester and vendors each had their own vending schedule that they followed throughout the year. The responses of the harvesters and vendors were grouped into five different categories of vending frequency; occasional vending which was reflective of the five (three harvesters and two vendors) who were seasonal vendors and did not sell the crab throughout the year, once a week, weekends (which were defined as Friday to Sunday) 3-5 days of the week, which was reflective of those who sold on the weekend and additional days during the week, and everyday vendors (Figure 43). Most of the harvesters (19 or 66%) and vendors (10 or 56%) sold on weekends, which is when most of them were found for the purposes of this project. The least popular grouping for harvesters was the “once a week” which was also one of the least popular for vendors along with the “everyday” grouping which each had one harvester and one vendor each fall within this category.

20 18 16 14 12 10 Harvesters 8 Vendors 6 4

2 Number Number Respondents of 0 Occassionally Once a week Weekends 3-5 days per Everyday week Frequency

Figure 43 Frequency of sale of crab by harvesters and vendors

5.3.3 The cost of land crabs

Crabs are displayed for sale to customers in their bound state either singly (Figure 44) which allows customers to choose the crab they want and have them weighed and sold to them based on a specific rate per pound defined by the vendor, or in pre-priced bunches (Figure 45), which generally consisted of a group of usually 3 to 5 crabs of a certain weight and or size which make up a bunch of a specified price.

Although the blue land crab and hairy land crab were different species, they were sold at the same prices. Most harvesters (59%) and vendors (94%) sold their crab at a specified rate per pound. The vendors‟ sale prices were found to be TT$5 more than the cost price, the price which they bought the crab for. These vendors‟ sale prices were found to be on par with the harvesters‟ sale prices. The rate per pound prices established by harvesters and vendors fell within five categories (Figure 46); TT$10-15, $15-20, $20-25, $25-30 and $30-35. The most popular price range listed by harvesters and vendors was TT$15-20 per pound with the least popular for the harvesters being both the TT$20-25 and TT$30-35 ranges.

Figure 44 Singly bound blue land crab displaying a pre-determined rate of $TT20 per pound

Figure 45 Crabs bound in bunches and displayed for sale on semi-permanent structures

6 Harvesters

4 Vendors Number Number respondentsof

0 10-15 15-20 20-25 25-30 30-35

Price (TT $)

Figure 46 Harvesters‟ and vendors‟ price per pound

For vendors the least popular price range was the TT$30-35 range. Using a conversion ratio of one pound is the equivalent of 455.6 g and using the average crab weight between the two species, which was found in this study to be approximately 180.0g, it can be estimated that you can get approximately two to three crabs per the pound, depending on their size, for this price.

The remaining harvesters and vendors sold their crab using a specified price per bunch. Although most of the pre-priced bunches sold by harvesters and vendors were typically 3-5 crabs in size, there could have been any number of crabs in a bunch with bunches being as small as two and as large as eight crabs per bunch. The crabs in these bunches are put together based on their weight and size with bunches consisting of smaller crabs having more in one bunch compared to bunches consisting of larger crabs which would have fewer. For example, one harvester sold both small and large crabs with bunches being sold at a rate of six for TT$30 and four for TT$45, respectively (Figure 47). The pricing of crab using this method is subjective and such prices varied greatly and were not standardised like the rate per pound method.

Figure 47 Range of prices given by interviewed harvesters and vendors per bunch of different sized crabs

Small Crab Medium Crab Large Crab

Harvester 4 for $25 4 for $35 4 for $40

3-4 for $20 3- 4 for $35 3- 4 for $50

5 for $40 4 for $40 3 for $40

- 4-5 for $35 -

4 for $20 - 4 for $40

8 for $40 5 for $40 -

- - 2 for $25

- - 8-10 for $100

4-5 for $30 - 4-5 for $40

6 for $30 - 4 for $45

5 for $20 - 3 for $60

5 for $25 5 for $35 -

Vendor - 5 for $40 -

Differential Pricing

Differential pricing, throughout the year, was found to be a side effect experienced as a result of the demand and supply patterns caused by seasonality. This phenomenon has been identified by respondents, as being further compounded by the cultural and or religious practices within the country. The two most prominent examples of this are the Hindu month of Kartik and the Christmas season. The month of Kartik is a season of fasting for Hindus within the country and meat is generally not consumed. It usually falls within the months of October and November, when the crab are still plentiful after their “running” season. This season of fasting results in harvesters and vendors experiencing a decrease in demand for the crab. This, in conjunction with the crab still being in abundance from the “running” season, results in lower prices being maintained. The opposite however, occurs during the Christmas season in late December which is when it was stated that the crab begin to get scarce, in preparation for their moulting season and although members of the Christian community do not fast during this time, the society on a whole generally participates in the traditions of the season and as such meals which do not involve crab become more popular at this time. The decrease in demand combined with the scarcity of the crab prompts them to raise their prices (Figure 48).

Figure 48 Annual cycle of differential pricing of crabs

5.3.4 Sale of land crabs

All of the vendors and all but one of the harvesters stated that they sold their crab to individuals with the remaining harvester stating that he sold the crabs he caught directly to a restaurant every week. The harvesters did not indicate whether or not their customers included vendors as well as the general public.

Once the crab was chosen by the customer it was either sold to them alive or dead depending on the customer‟s request. To kill the crab, the vendor would remove the back of the crab by pulling it off with their hands and discarding it. The remaining body of the crab, which mostly comprises the legs of the crab, would be cut in half (Figure 49). The pointed tips of the walking legs or the dactylus would also be cut off and discarded. This leaves the customer with the legs, the most desired part of the crab as it contains the most meat. In addition, if the crab purchased was a hairy land crab, some sellers also provide the service of free cleaning of the legs of the crab, by scraping a sharp knife along the length of the legs (Figure 49).

Figure 49 Preparation of hairy crab by a vendor, showing (top left and right) crabs after the back is removed and each crab is cut in half, and (bottom) the process of removing the hairs on the legs of the crab

5.3.5 Popularity of each species

Most harvesters caught and sold both the blue and hairy land crabs (16 respondents, 55%), whilst most vendors (10 respondents, 56%) sold blue crab only and hairy crabs were the least popular crab for sale amongst both harvesters and vendors (Figure 50 and Figure 51).

Incentives such as the removal of the hair along the legs of the hairy land crab, are provided by harvesters/vendors to encourage customers to purchase this particular species as according to harvesters and vendors, customers view this as additional work and this is often the reason why the blue land crab is more popular and more readily bought by the general public (Figure 52). Despite the fact most harvesters and vendors may have listed a particular species as being more popular than the other, they were unable to give a reason as to why they were more popular. However, of those who gave reasons, the majority of those who stated it was the blue crab also stated that it was as a result of it having less cleaning while those who stated that it was the hairy crab believed it was because this particular species was “sweeter” and tasted better than the blue crab (Figure 53).

Figure 50 Types of crab caught and sold by crab harvesters

Figure 51 Types of crab bought and sold by crab vendors

8 Harvesters

6 Vendors

4 Number Number respondentsof 2

0 Blue Hairy Neither

Figure 52 Harvesters‟ and vendors‟ perceptions of the most popular crab species amongst the general public

Harvesters- Blue 6 Harvesters- Hairy 4 Vendors- Blue Vendors- Hairy Number Number resondentsof 2

0 Taste Price Less cleaning Area of No reason country

Reason for popularity

Figure 53 Harvesters‟ and vendors‟ reasons for each species‟ popularity

5.3.6 Quantity of crab sold

Most harvesters and vendors sell their crab at a particular rate per pound, as such they were all asked to give the amount of crab they sold per week in pounds. None of the harvesters and vendors kept records of how much they sold and as such the responses were given as approximate ranges. The responses provided were grouped into five different ranges; 1-50 lb, 51- 100 lb, 101-150 lb, 151-200 lb and over 200 lb and another grouping provided for those who

51 were unable to provide a response. Harvesters and vendors were almost equally distributed throughout all the groups. The highest grouping (>200 lb per week) was the most frequently stated by harvesters (six harvesters or 21%) and was also one of the most frequently stated amongst vendors along with the lowest grouping of 1-50 lb per week with each having four (22%) vendors each (Figure 54). All harvesters and vendors stated that they sold all the crab that they caught and bought and did not keep any of it for personal use or otherwise.

Harvesters 3 Vendors

2 Number Number Respondents of

0 1-50 51-100 101-150 151-200 >200 unsure Weight of crabs sold (lb)

Figure 54 Quantity of crab sold per week by harvesters and vendors

5.4 The Mangrove land crab resource

5.4.1 Size

A total of 220 crabs, which consisted of 110 hairy land crabs and 110 blue land crabs, was sampled opportunistically. The carapace width was measured and the gender determined for all 220 crabs while 50 each of both species; 100 in total, were also weighed. The width of the carapaces of the blue land crabs ranged from 55.90 mm-108.20 mm with a mean of 73.55 mm while those of the hairy land crabs ranged from 54.50 mm - 90.00 mm with a mean of 74.03 mm (Figure 55,Table 4). Statistical analysis of the carapace width of the blue and hairy crab revealed that the measurements of the blue crab were not normally distributed (Shapiro-Wilk: df = 110; P = 0.000) while those for the hairy crab were (Shapiro-Wilk: df = 110; P = 0.569) (Appendix 4), this was reflected in the carapace frequency plots for both species (Figure 56, Figure 57). There was a significant difference between the carapace width of male and female blue crabs (Mann Whitney: U = 841.50, n = 110, p = 0.005) while there was not a significant difference between the carapace width of male and female hairy crabs (t-test: t = 1.217,df = 108, p = 0.226) nor was there a significant difference between the carapace widths of blue and hairy crabs (Mann Whitney: U = 5390.0, n = 220, p = 0.163) (Appendix 4).

Table 4 Maximum, minimum and mean carapace width and weight of each species of crab

Parameter Species Number of Minimum Maximum Mean Standard Crabs Deviation

Carapace Blue Crab 110 55.90 108.20 73.55 9.34 Width (mm) Hairy Crab 110 54.50 90.00 74.03 6.08

Weight (g) Blue Crab 50 75.00 350.00 185.50 68.06

Hairy Crab 50 75.00 275.00 178.58 48.25

120

100

Carapace Width (mm) 20

0 Blue Crab Hairy Crab Crab Species

Figure 55 Box and Whisker Plot comparison of the carapace widths of blue and hairy crab

6 Female

Frequency 4 Male

0 55 60 65 70 75 80 85 90 Carapace Width (mm)

Figure 56 Carapace width frequency for hairy crab

6 Female Male

Frequency 4

0 55 60 65 70 75 80 85 90 95 100 105 Carapace width (mm)

Figure 57 Carapace width frequency for blue crab

The weights of each crab species also followed the trend where the blue crab was not normally distributed (Shapiro-Wilk: df = 50; p = 0.000) but the hairy crab were (Shapiro-Wilk: df = 50; p = 0.151) (Appendix 4) which was reflected in the weight frequency distribution for each species (Figure 58, Figure 59) The weight of the blue land crabs ranged from 75 – 350 g with a mean of 185.50 g while the weight of the hairy land crabs ranged from 75 – 275 g with a mean of 175.6 g (Figure 60 and Table 4). There was a significant difference between the weights of male and female blue crabs (Mann Whitney: U = 153.5, n = 50, p = 0.008) and the weights of male and female hairy crabs (t-test: t = 2.591, df = 48, p = 0.013) however, there was no significant difference between the weights of blue and hairy crabs (Mann Whitney: U = 1224, n = 50, p = 0.259) (Appendix 4).

9 8 7

4 Female Frequency 3 Male 2 1 0 75 100 125 150 175 200 225 250 275 Weight (g)

Figure 58 Weight frequency for hairy crabs

Female 4 Frequency Male 3

0 75 100 125 150 175 200 225 250 275 300 Weight (g)

Figure 59 Weight frequency for blue crabs

400 350 300

250 200

150 Weight (g) 100 50 0 Blue Crab Hairy Crab Crab Species

Figure 60 Box plot comparing the weights of blue and hairy crab

The weight-width relationships of the male and females for each species was also plotted so as to determine the type of growth pattern that each gender in each species undergoes. Based on the

55 equations which each represent the form y=axb, the males and females of both species experienced negative allometric growth where b < 3 (Figure 61 and Figure 62.

(a)

300 Hairy crab (males)

250

200

y = 0.0529x1.8859 150 R² = 0.4613

Weight (g) 100

0 40 50 60 70 80 90 100 Carapace Width (mm)

(b)

300 Hairy crab (females)

250 y = 0.0006x2.9023 R² = 0.5504

200

150

100 Weight (g)

0 40 50 60 70 80 90 Carapace Width (mm)

Figure 61 Weight-width relationship for hairy crabs showing (a) males and (b) females separately

(a)

400 Blue crab (males) y = 0.001x2.8203 350 R² = 0.802

300

250

200 Weight (g) 150

100

0 40 50 60 70 80 90 100 Carapace Width (mm)

(b)

250 Blue crab (females)

y = 0.0019x2.6563 200 R² = 0.5983

150

Weight (g) 100

0 40 50 60 70 80 Carapace Width (mm)

Figure 62 Weight-width relationship for blue crabs showing (a) males and (b) females separately

5.4.2 Gender

The males and females were quite similar in general appearance but were easily differentiated by the shape of their abdomen and/ or the colour of the crab in the case of the blue crabs (Figure 63) or the presence of hair on the legs in the case of the hairy land crabs (Figure 64).

Figure 63 Male and female blue land crabs showing (top) differential colour between genders; blue male and white female; (bottom left) the shape of the abdomen of the female; and (bottom right) the shape of the abdomen of the male

Figure 64 Male hairy land crab with hair on the ambulatory legs (top). Female hairy land crab with the absence of hair on the ambulatory legs (bottom)

In both the sampled populations of 110 blue and 110 hairy crabs, males dominated the group, with the blue crab sample group containing 77 males (70%) (Figure 65) and the hairy crab sample group containing 74 (67%) males (Figure 66). This meant that these samples exhibited a ratio of approximately two males to every female (Table 5).

30% Male Female 70%

Figure 65 Gender composition of a sample of blue crabs

33% Male Female 67%

Figure 66 Gender composition of a sample of hairy crabs

Table 5 Male to female ratio for each species of crab

Species Males Females Calculation Ratio

Blue Crab 77 33 77/33 = 2.33/1 2:1

Hairy Crab 74 36 74/36 = 2.06/1 2:1

Of the 110 blue and 110 hairy crabs sampled and measured, only the blue crab sample were found to contain juveniles; with one female being less than the 58.7 mm carapace width threshold and six males being less than 62.2 mm. The juveniles therefore, represented a limited percentage of the population (7 blue crabs or 6%) (Table 6).

Adults Juveniles

94%

Table 6 Percentage of juveniles in the blue crab sample

Egg-carrying (or „berried‟) females were not found amongst any of the crabs sampled, neither were they observed being sold. This was reflective of harvesters‟ responses and views on this issue as they would catch the crabs as they make their way back from the sea during “running season”. Alternatively, if they did catch berried females, they would wash them off in the water before taking them. This was a practice that they stated most of the recreational harvesters did not adhere to.

5.4.3 Perceived state of the land crab resource

More than half (16 respondents, 55%) of the harvesters interviewed stated that they have noticed a change in the number and size of the crabs they catch, in that the size and/ or abundance of these crabs has decreased over the years. Of this 16, three harvesters were unsure as to what exactly caused this change, while the other 45% provided three main reasons for this occurrence which included; mangrove degradation, over exploitation and obstruction of rivers (Figure 67).

These figures and responses were similar amongst vendors, with half (9 vendors, 50%) stating that they had noticed a change; in the form of a decrease in the availability of the crab over the years in terms of the size and/or abundance of the crab that they were getting. Only five (28%) were able to provide a possible cause for this change with the other four (22%) stating that they were unsure as to what had caused these changes. However, vendors also provided the same reasons for these changes as the harvesters with the exception of the obstruction of rivers (Figure 68).

Over exploitation of the crab resource proved to be the most popular reason, which was listed by nine of the harvesters and three vendors as the cause of this change. Many harvesters attributed this to the popularity of the “running season”, the number of crabs harvested during this season and the lack of knowledge of those recreational harvesters who capture the crab before they have been able to release their young into the sea, thereby affecting the future stock. Two harvesters also indicated that with respect to harvesting methods, they had observed that other harvesters had started to use whole nets draped across the mangrove floor instead of cutting squares to be staked over the holes of the crab resulting in larger amounts being captured than necessary. Due to the large size of these nets they often get tangled with crab in them and they are left and discarded in the mangrove leading to more crab being tangled in the net resulting in a type of “ghost harvesting.”

Mangrove degradation was listed by two harvesters and vendors each while the obstruction of rivers was only listed by two harvesters with no vendors listing this as a possible cause for the changes observed. The harvesters who listed mangrove degradation were both users of the Caroni swamp and they stated that chemicals were being dumped in the mangrove and its surrounding environment by factories and other companies which were causing the mangroves themselves to die thereby affecting the mangrove land crab habitat and their abundance and size. The blockages which caused the river obstructions were not identified as being man-made or natural however, both harvesters stated that these blockages affected the regular flow of the river and caused changes in their surrounding environments which, in turn, decreased the abundance of crab in those areas.

31%

45% 55% 7%

7% 10% No change Observed changes Mangrove degradation Over exploitation Obstruction of Rivers Unsure

Figure 67 Harvesters‟ suggested causes for the perceived state of the mangrove land crab resource and the factors affecting the resource

17%

50% 50%

22% 11%

No change Observed changes Mangrove degradation Over exploitation Unsure

Figure 68 Vendors‟ suggested causes for the perceived state of the mangrove land crab resource and the factors affecting the resource

Ten of the 16 harvesters and all nine of the vendors were able to indicate an approximate timeframe over which they have observed these changes to the resource occurring, with responses ranging between 1-5, 6-10 and over 10 years (Figure 69). Amongst harvesters, the most frequently chosen timeframe was 1-5 years with a decreasing number of responses with increasing time range. Conversely, the most frequently stated time range amongst vendors was the highest time range of over 10years, with no vendors choosing the 6-10 years timeframe.

4 Harvesters 3 Vendors

2 Number Number respondentsof 1

0 1-5 6-10 Over 10 Unsure Years

Figure 69 Perceived time frame over which changes to the land crab resource have occurred

Despite this, most of those who stated that they had observed changes over the years (11 harvesters and 8 vendors) did not feel the need to switch their choice of harvest site or their 63 source of crab respectively as a result of these changes. The five harvesters who indicated that they had felt the need to change their choice of harvest site had not switched to other mangrove ecosystems, but had simply switched to other areas within the same mangrove ecosystem. Conversely, the single vendor who said that they had switched sources, indicated that they had not switched from one local harvester to another but that the harvester who they bought their crab from had switched from one ecosystem to another; from Manzanilla to Mayaro, both on the eastern coast of the island.

6 DISCUSSION

6.1 The fishery

Mangrove land crab catching has a long history in Trinidad, with shell midden sites containing crab chelae dating back to 5000 B.C. being found on the island (Ali 2012). The mangrove land crab fishery of Trinidad is a small-scale fishery involving the active targeted harvesting of blue land crabs (Cardisoma guanhumi) and/or hairy land crabs (Ucides cordatus) for sale to the general public. Formal information on these species and the mangrove land crab fishery in this country is limited, and this state of affairs is reflective of the general nature of information on this fishery throughout other Caribbean territories. For example, only mention is made of the presence and use of these crabs, mostly the blue land crab, in other islands such as Jamaica (Warner 1969, Vee 1988 and Quinn 2006), St. Lucia (Morton 2009), Guyana (Allan et al. 2002) and the Bahamas (Blick 2012). The only formal recording of crab fisheries statistics appears to be that of Puerto Rico (Matos-Caraballo 2007).

Despite the lack of formal data, it is clear that the mangrove land crab fishery of Trinidad is thriving, and appears to be similar in terms of extent, economic and social importance to the mangrove land crab fisheries of South America; such as those found in Brazil and Venezuela.

The term “socially universal fishery” was used to describe the land crab fishery of Jamaica by Quinn (2006). This term is a true representation of the mangrove land crab fishery of Trinidad as men, women, the young and the old are all found to be represented within this fishery. A total of 29 harvesters, who also sell their harvest, and 18 vendors were found and interviewed across the island, of which females made up a relatively high percentage of harvesters (28%) and vendors (67%). The role of women in fisheries in Trinidad is undocumented (Mohammed et al. 2011) but this pattern follows the general trend in Caribbean fisheries where women are less involved in the active fishing or harvesting but dominate the post-harvest sector (Baldeo 2011, McConney 2011 and Valle-Esquivel et al. 2011). Conversely, in Guyana, women were found to be the main crab harvesters (Allan et al. 2002). Through informal discussions with the women involved in the fishery in this study, it was found that their involvement in the fishery was influenced by the traditions of the families in which they grew up, or by the practices of their husbands. This included failed relationships or the loss of income by the main bread winner in the home that spurred them to turn to the fishery as a quick and relatively easy way to earn income. This highlights the importance of this fishery as a social/livelihood safety net.

According to the results of this study, entry into this fishery is relatively simple in Trinidad. There are no licences needed, there is minimal need for capital investment, especially for harvesters as the price of harvesting materials is minimal to non-existent, bait is readily available

64 in the form of fruits and leaves and often times harvesters live within walking distance of their chosen harvest sites which nullifies the cost of or the need for transportation. Some, however, were found to require a boat and forms of public or private transportation to access their harvest sites. Transportation costs related to harvest activities may range between TT$10-200 per trip. These trends and low costs associated with the fishery are also seen in the Brazilian fishery where harvesters also have few inputs and will also walk to their harvest site if possible (Araujo 2006). The use of boats by harvesters is also a common occurrence in the crab fishery of Brazil, as many harvest sites are only accessible from the coast. Likewise, in Trinidad, certain harvest sites within the Caroni swamp were unreachable by land, and as such most of the harvesters who used a boat were those using this area. Unlike Trinidad harvesters however, who stated that they paid boat operators fees for fuel for the boat, Brazilian harvesters were found to either make their own boats (Firmo 2012) or pay the boat operators with part of their catch (Araujo 2006). Other than the financial inputs associated with transport, the main inputs by harvesters were reflected in the time which the harvesters spent catching the crab. Most harvesters in Trinidad harvested upwards of three days per week and the length of these trips ranged from a few hours to whole day trips, with half and whole day trips being the most common. This is very similar to the 3-5 days per week, 5-8 hour long trips which are typical of harvesters in Bahia State, Brazil (Firmo 2012). Conversely it is unlike the fishery in Jamaica where a typical trip lasts two to four hours, and harvesters simply harvest crabs from along the sides of the road (Quinn 2006).

Harvesters and vendors were found throughout the island, although the majority were located in the western-central area of the island. This is believed to be the typical pattern for the crab fishery in Trinidad, however, it may be slightly biased by the limited ability of the researcher to visit and explore the other coasts and areas of the island as frequently as the western-central area. The ethnic composition of the population within these areas, including Chaguanas, Couva etc., is primarily of East Indian descent, according to the Central Statistical Office of Trinidad and Tobago (2012), and this was reflected in the ethnic composition of the crab harvesters and vendors.

Harvesters‟ were found to obtain their crab from eight different mangroves throughout the island, with the residential locations of the harvesters being in close proximity to their chosen harvest site. This reflects the views of Quinn (2006) who stated that these crabs are traditionally harvested by people inhabiting coastal areas throughout the Caribbean. The Caroni swamp, a protected area and Ramsar site, on the west coast, is the largest mangrove habitat in Trinidad and it was also the most popular harvest site. The use of this site for crab harvesting is recorded in several documents (e.g. James et al. 1986, Gibbes et al. 2008) although it has not been further described until now.

Bamboo, board or net traps, hooks and free-hand harvesting are the main methods of capture of these crabs with the bamboo and net traps being the most widely used methods for blue and hairy land crabs, respectively. These methods were found to be utilised in other land crab fisheries around the world such as in Brazil (Araujo 2006, Nascimento et al. 2011 and Firmo et al. 2012) and the Philippines (Maitland 2002). The use of net traps, which involves the covering of the entrance of the crab hole with a net which is staked firmly over it, is said to have been invented in Brazil in the 1980s (Nascimento et al. 2011). This method is commonly called “redinha” in that country. However, the use of net traps in Brazil has now been outlawed due to the fact that important stages in the crabs‟ life cycle can be affected through the use of this method, as gravid

65 females and moulting crabs are not excluded from capture. The net pieces are also often lost or abandoned, since over 100 of these traps are regularly set per harvesting trip by each harvester, causing pollution. Furthermore, when the crabs become entangled in the net and are left there, it encourages prey such as the crab-eating raccoon, and the discarded nets with entangled decomposing crabs is believed to drive away other crabs from the area (Araujo 2006, Nascimento et al. 2011). This method is commonly used in Trinidad and most harvesters who utilise these net traps were found to set 80 to over 100 traps per trip. All these impacts have been listed and described by harvesters interviewed as some of the major issues that they experience, without realising that the use of the method itself has been found to be harmful to the fishery. It is issues such as these that highlight the need for proper monitoring, management and continuous studies to be done on the fishery, so as to ensure that best practices are employed and that the actions of the harvesters themselves are not harmful to the fishery on which they themselves are reliant.

The majority of harvesters and vendors were found to harvest and sell crab most of the year, barring the moulting season during the months of March to May when they are scarce. This, along with the “running” or spawning season during the months of July to September, when the crab are abundant, exhibits the seasonality of the fishery which is experienced by harvesters and vendors in Trinidad and in other territories as well. These seasons do not occur over the same time period in every country. In fact they may even be different within a country. For example, in some parts of Brazil the moulting season can occur during July and August while the spawning season may occur during the months of December and February (Firmo et al. 2012). Conversely, in another state these seasons can occur during the months of May to August and December to April, respectively (Araújo 2006).

Our study corroborates the information given in an interview and reported in a local newspaper article by Waldropt-Ferguson (2012). The article gives insight into the typical life of, and dependence of, harvesters and vendors in the crab fishery in Trinidad. According to the article, the interviewed crab vendor, Sita Ali, was “born” into the crab business, learning to catch crabs from her grandparents. Her immediate family, who she sources her crabs from, is also involved in crab catching, though she herself only sells the crabs and has been doing so for the past five years. Being from Couva on the western coast of the island, they harvest from the mangroves within this area including the Caroni swamp. She indicates, in the article, that this is her main livelihood. Her story also indicates the theme of tradition that was found to be an important factor in this fishery; the input and involvement of family during harvesting trips; the manner in which crabs are sold to customers; the postharvest processing; and the importance of the fishery as a livelihood for persons and their families involved in the fishery.

The crabs examined in our study have very similar size and weight characteristics as harvested crabs of the same species in other studies (e.g. in Brazil: Dalabona et al. 2004, Shinozaki- Mendes et al. 2012; in Jamaica: Quinn 2006). In our study, carapace width measurements were used to indicate the presence of juveniles using the parameters stipulated by Shinozaki-Mendes et al. (2012) for blue crab and Pinheiro and Hattori (2005) for hairy crab in NE Brazil. In view of the fact that there are no restrictions on the harvesting of crab in Trinidad and Tobago, it was interesting to discover that the harvested population had very few juveniles. It is unclear however, whether the paucity of juveniles in the catch results from low abundance of juveniles at harvesting sites or active avoidance of crabs below a certain size by the harvesters.

The weight-width relationship has been used by some authors (e.g. Pinheiro and Fiscarelli 2008, Araújo et al 2012) to determine the type of growth and even the “well being” of the population which can change with season (Pinheiro and Fiscarelli 2008). As such, samples taken at a different time of year to could be used to compare the crab population condition with our own summer samples.

6.2 Post harvest and retail

There are no formal „landing‟ sites or harvest records for the Trinidad and Tobago crab fishery. Even the harvesters themselves do not keep records of how much they catch per trip, and were therefore only able to give estimates during interviews. This is an undesirable situation, making it very difficult to access and monitor the status of the resource over the long term. According to Jablonski et al. (2006), harvest data is essential for evaluating the economic value and performance of the resource and allowing for appropriate compensation in the event that conflicts arise.

The crabs‟ life cycle not only affects annual harvesting patterns but also affects prices, with prices rising during periods of low supply (i.e. March to May). This has also been reported in Jamaica (Quinn 2006) and Brazil (Araújo 2006). The regular price of crab in Trinidad at TTD $15-20 per pound (USD $2.35-3.12) falls within the range of prices reported from elsewhere across the region, for example: in Jamaica JD $500-800 (USD $5.06- 8.10) for 8-12 crabs (Quinn 2006); in the Turks and Caicos USD $3.00-5.00 per crab, (Manco 2008); in Guyana, GD $200- 250 (USD $0.98-1.22) per 15-20 crabs (Allan 2002); and in Brazil R$1.00 (USD $0.47) per 14 crabs (Araújo 2006).

In Trinidad, the demand for crabs supports full time harvesters and vendors whose livelihoods depend on the fishery, as well as recreational harvesters, who traditionally harvest crabs only during the “running season” but retail their excess crab harvest to the public. This suggests that there are viable economic returns to be gained in this fishery. It also appears as though the demand for crab in Trinidad exceeds the local supply, as indicated by the illegal importation of crabs from neighbouring Venezuela. This issue was highlighted by some of the interviewed harvesters and vendors, and has been reported by Carmona-Suarez (2011) from Venezuela as well as a local newspaper report by Anna Poliah (TnT Mirror Weekend Edition, May 12, 2013) in which she reported that several persons were caught in the act of buying crabs from Venezuelans.

6.3 Socio -economic contribution

Although there are no recorded exports and the economic value of the crab fishery is likely to be negligible compared with other fisheries in Trinidad and Tobago, there is no doubt that it provides an important source of income to an appreciable number of harvesters and vendors and provides an important security during hard times. Most harvesters and vendors (72% each) reported that the crab fishery was their main source of income, with over 50% each indicating that it was their sole source of income. Using the responses provided by interviewees; a typical harvester and vendor sells crab at TT$15-20 per pound and the modal quantity of crab sold per week reported by harvesters and vendors is over 200 pounds per week. This means that crab

67 harvesters and vendors could be grossing between TT$3,000-4,000 (USD$467-623) per week on average from a fishery that requires little to no financial input.

This fishery is also of cultural significance in Trinidad, as the catching of crabs by the general public during the running season is considered a traditional activity and involves large numbers of the local population.

6.4 Management

The mangrove land crab fishery is an open access, unmonitored, unmanaged fishery; characteristics which have led to the demise of many other fisheries throughout the world. This study has revealed that approximately 50% of the interviewed harvesters and vendors perceive that the size and abundance of mangrove land crabs over the years has decreased in Trinidad, with most of these collectively stating that it has occurred over the past 10 years. Harvesters were able to better indicate the cause of this possible decline due to their first hand interaction with the resource and its habitat and they related it to mangrove degradation, overexploitation and blocked river ways. With respect to the degradation of the mangroves they indicated that the mangroves were being polluted from upstream factories and industries that were releasing toxic effluent into the water, which eventually reaches and kills the mangrove trees, thereby reducing the mangrove land crab habitat. As a result of this observation, they suggested the need for better monitoring and policing of these industries and possible fines for their actions. Overexploitation was mainly attributed to the recreational harvesters who become engaged in the fishery during the “running season”. The full time (commercial) harvesters stated that as persons who have generally been in the fishery for many years and depend on the fishery, they practice the capturing of female crabs only after they have released their eggs, or if a gravid female is caught, the harvesters wash the eggs off into the sea before taking the crab. They stated that these practices were not followed by the recreational harvesters. This, coupled with the hundreds of people taking hundreds of crabs during their annual reproductive season, is having a negative effect on the future land crab populations. This is clearly an area of conflict between the recreational and commercial land crab fishers. As a result of these issues some harvesters indicated that although they are happy to be able to freely operate within the fishery, they believe that there is some need for management as these issues affect their livelihood and there is nothing that they can do about it without the aid of regulation and enforcement measures.

Apart from this, there are many management issues which have been highlighted by this study, they include:

 The need for effective monitoring of the crab fishery. Harvesters and vendors have reported on the perceived degradation of the resource and suspected causes. However, the harvesters themselves do not realise that they are using a method of crab capture that has been banned in another country due to its adverse effects on the resource and the crab habitat. An effective landing data collection system is needed to determine the approximate annual amount of crab harvested and any changes to this, so as to give a better idea of the state of the resource.

 What is the best way to monitor such an informal and open access fishery? People can easily enter and leave this fishery, there are no records as to the current number of

persons involved, and with the number of harvesting sites throughout the country, the labour and inputs needed to implement monitoring and enforcement would be substantial. However, with harvesters having a great self interest in sustaining this fishery and their vast traditional knowledge, it should be possible to initiate some form of “community based” management system whereby harvesters record their own catches and users of the same harvest sites can monitor each other‟s actions and encourage best practices.

 What would be the socio-economic impact on the harvesters and vendors if management tools and regulations were implemented? The dependence on the crab fishery as a source of income throughout the year means that if the need for a closed season or other restrictions is realised, whole families will be significantly affected as this is their main source of income.

7 CONCLUSION

This study was able to not only document the characteristics of the blue and hairy mangrove land crab resource in Trinidad but to also describe the characteristics, roles and functions of two of the main stakeholder groups in this fishery: the harvesters and vendors. The study provides an insight into their interactions not only with the resource, but with each other and the general public.

Through the information provided by the 29 crab harvesters and 18 vendors, their harvesting and vending locations, harvesting and vending practices, seasonality and availability of the resource, catches, sales and economic dependence on the fishery, the importance of the resource and the contribution to the livelihoods of these stakeholders have been illuminated. There has been no previous documentation of the state of the resource before now, and as such it is unclear whether the resource has been depleted over the years or not. However, the indication that the mangrove habitat of these crabs is being affected, the observations of decreasing abundance and size by harvesters and vendors and the potential impacts of the poor practices of other stakeholders on the resource and the livelihoods of these harvesters and vendors are definite cause for concern.

The data acquired throughout this study highlight the need for further, more rigorous studies on the fishery and the stakeholders involved, while providing baseline information which can facilitate the development of a national management plan for the crab resource. Such a plan should aim to ensure not only that the hairy and blue land crab resources are maintained, but that there is sustainable use of these resources and that the livelihoods of the stakeholders involved are not compromised through factors internal and external to the fishery. Public awareness programmes can also be developed which target and educate those members of the general public who become recreational harvesters during the “running season” about best practices to adopt when becoming engaged in the fishery.

The crab resource in Trinidad remains essentially unmanaged and unprotected. This not only affects the country locally, but also hinders the achievement of goals stipulated by international agreements to which Trinidad and Tobago is either a contracting member or a signatory party. These include the Convention on Wetlands of International Importance Especially as Waterfowl Habitat (Ramsar Convention), the Convention on Biodiversity (CBD) and the Protocol

69 concerning Specially Protected Areas and Wildlife to the Cartagena Convention (the SPAW Protocol). The information provided here can help Trinidad and Tobago to fulfil these commitments, leading to a better international standing.

8 REFERENCES

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9 APPENDICES

Appendix 1: Crab vendor survey

CRAB VENDOR SURVEY

Data Collector: ……………………. Date: …………………. Number……………………..

GPS Waypoint# ……………….. N………………………… W………………………………

Interview Location: ...... ………… Harvester ID: ………………………………..

1. Is this the only place you sell crab? Yes? No?

2. If no, where else? ......

3. What type(s) of crab do you sell? ……………………………………………………………….

4. How do you obtain the crab? Import? Locally? Other………………………………......

5. Why do you choose to obtain the crab through this means? …….…………......

6. Do you sell crab year round? Yes ? No ? (If yes, skip to Q6. If no, go to Q5)

7. If no, what times of the year do you sell and why? ......

8. How often do you sell crab? ……………………………………………………………………

9. Who are your main buyers? Individuals? Caterers? Restaurants? Other? …………………...

10. What price do you pay for the crab you sell? ......

11. What price do you sell the crab at? ……......

12. Are there different prices at different times during the year? Yes? No?

Explain…………………………………………………………………………………………...…

13. What quantity of crab do you sell per week? …......

14. Which is the most popular or frequently sold type of crab? Explain …………………………..

………………………………………………………………………………………………………

15. What is the seasonal availability of crab? ......

16. Have you noticed a change in the availability and the size of crabs over the years? Explain

………………………………………………………......

17. Over what time period have you noticed this change? ………………………………………...

18. What do you think is the cause of this change? ......

......

19. Has this change led you to switch sources for crab? Yes? No?

Explain……………………………………………………………………………………………...

SOCIO-ECONOMIC CHARACTERISTICS

20. Gender of Harvester: Male? Female?

21. Ethnicity of Harvester: African? Indian? Chinese? Syrian? Lebanese? White? Mixed? Other? ......

22. What age group do you belong to? 20 & under? 21-30? 31-40? 41-50? 51-60? Over 60?

23. Where are you a resident of? ......

24. How long have you been selling crabs? ………………………………………………………..

25. Is it a tradition or simply a source of income? …………………………………...…………….

26. Is crab vending your main source of income? Yes? No?

27. If no, what other activities do you earn income listing in order of importance?

………………………………………………………………………………………………………

28. What percentage of your annual income would you say is derived from the sale of crabs?

<25%? 25-50% 50-75% >75%

29. Do you know of other crab vendors and or harvesters, and if so please provide contact information, if possible: …………………………..………………………………………………..

Appendix 2: Crab harvester survey

CRAB HARVESTER SURVEY

Data Collector: ……………………. Date: …………………. Number……………………..

GPS Waypoint#...... N………………………..…… W…………………………………

Interview Location: ...... ………… Harvester ID: ………………………………..

1. Is this the only place you sell crab? Yes? No?

2. If no, where else? ……......

3. Where do you catch your crab? …………………………………………………………………

4. What type(s) of crab do you catch? ……………………………………………………………..

5. Do you find different crab species in different areas? Explain

…………………………………………………………………………………………………….

6. Do you catch crab year round? Yes ? No ? (If yes, skip to Q8. If no, go to Q7)

7. If no, when do you harvest and why? ......

………………………………………………………………………………………………………

8. How often do you harvest? ......

9. In your opinion when is the best time of the year to catch crab and why?

………………………………………………………………………………………………………

10. On average what quantity of crab do you catch per trip? ......

11. Do you sell all the crab that you harvest? ……………………......

12. How often do you sell crab? …………………………………………………………………..

13. Who are your main buyers? Individuals? Caterers? Restaurants? Other……………………….

14. What price do you sell the crab at? ……......

15. Are there different prices at different times during the year? Yes? No?

Explain…………………………………………………………………………………………...…

16. What quantity of crab do you sell per week? …......

17. Which is the most popular or frequently sold type of crab? Explain …………………………..

………………………………………………………………………………………………………

18. How do you catch the crab? Describe the equipment and method that is used:

………………………………………………………………………………………………………

……………………………………………………………………………………………………....

19. If gear is used, how much is set per trip? ………………………………….

20. Why do you prefer that method? Tradition? Cost? Preference? Other ………………………...

………………………………………………………………………………………………………

21. Do you harvest: Alone? With family? Friend(s)? Other………………………………………..

22. How much time do you spend on each trip? ......

23. On average, how much does each trip cost, in relation to transport, gear, bait etc.?

………………………………………………………………………………………………………

24. Have you noticed a change in the number and size of crab at the sites you use? Explain

………………………………………………………………………………………………………

25. Over what time period have you noticed this change? ………………………………………...

26. What do you think is the cause of this change? ......

......

27. Has this change led you to switch harvesting sites and why? ......

……………………………………………………………………………………………………… SOCIO-ECONOMIC CHARACTERISTICS

28. Gender of Harvester: Male? Female?

29. Ethnicity of Harvester:

African? Indian? Chinese? Syrian? Lebanese? White?

Mixed? Other? ......

30. What age group do you belong to?

20 & under? 21-30? 31-40? 41-50? 51-60? Over 60?

31. Where are you a resident of? ......

32. How long have you been catching crabs? ……………………………………………………...

33. How long have you been selling crabs? ………………………………………………………..

34. Is it a tradition or simply a source of income? ……………………………………………….

35. Is crab vending your main source of income? Yes? No?

36. If no, what other activities do you earn income, listing in order of importance?

………………………………………………………………………………………………………

37. What percentage of your annual income would you say is derived from the sale of crabs?

<25%? 25-50% 50-75% >75%

38. Do you know of other crab vendors and or harvesters, and if so please provide contact information, if possible: ………………………………………………………………………….

Appendix 3: Biological data form

BIOLOGICAL DATA FORM

Date Species Carapace Width (mm) Estimated Total Weight Sex (g)

Appendix 4: Statistical Outputs

Shapiro-Wilk test for normality on Hairy Crab Carapace Widths

Kolmogorov-Smirnova Shapiro-Wilk

Statistic df Sig. Statistic df Sig.

Hairy_Crab .050 110 .200* .990 110 .569

*. This is a lower bound of the true significance. a. Lilliefors Significance Correction

Shapiro-Wilk test for normality on Blue Crab Carapace Widths

Kolmogorov-Smirnova Shapiro-Wilk

Statistic df Sig. Statistic df Sig.

Blue_Crab .155 110 .000 .920 110 .000 a. Lilliefors Significance Correction

Shapiro-Wilk test for normality on the weights of Hairy Crab

Kolmogorov-Smirnova Shapiro-Wilk

Statistic df Sig. Statistic df Sig.

Hairy_Crab_Weight .105 50 .200* .965 50 .151

*. This is a lower bound of the true significance. a. Lilliefors Significance Correction

Shapiro-Wilk test for normalityon the weights of blue crab

Kolmogorov-Smirnova Shapiro-Wilk

Statistic df Sig. Statistic df Sig.

Blue_Crab_Weight .201 50 .000 .899 50 .000 a. Lilliefors Significance Correction

Mann Whitney U Test comparison of means on the carapace widths of male and female blue crabs

Gender N Mean Rank Sum of Ranks

Male 77 61.07 4702.50

Blue_Crab_Width Female 33 42.50 1402.50

Total 110

Test Statisticsa

Blue_Crab_Width

Mann-Whitney U 841.500

Wilcoxon W 1402.500

Z -2.798

Asymp. Sig. (2-tailed) .005

Exact Sig. (2-tailed) .005

Exact Sig. (1-tailed) .002

Point Probability .000 a. Grouping Variable: Gender

T-Test comparison of means on the carapace widths of male and female hairy crabs

Gender N Mean Std. Deviation Std. Error Mean

Male 77 74.5873 6.29054 .71687 Hairy_Crab_Width Female 33 73.0485 5.52891 .96246

Independent Samples Test

Hairy_Crab_Width Levene's Test for t-test for Equality of Means Equality of Variances

F Sig. t df Sig. (2- Mean Std. Error 95% Confidence tailed) Difference Difference Interval of the Difference

Lower Upper

Equalvariances .518 .473 1.217 108 .226 1.53879 1.26395 -.96657 4.04415 assumed

Equal variances not 1.282 68.480 .204 1.53879 1.20010 -.85567 3.93324 assumed

Mann Whitney U Test comparison of means between the carapace widths of blue and hairy crabs

Species N Mean Rank Sum of Ranks

Blue Crab 110 104.50 11495.00

Crab_Width Hairy Crab 110 116.50 12815.00

Total 220

Test Statisticsa Crab_Width Mann-Whitney U 5390.000 Wilcoxon W 11495.000 Z -1.398 Asymp. Sig. (2-tailed) .162 Exact Sig. (2-tailed) .163 Exact Sig. (1-tailed) .081 Point Probability .000 a. Grouping Variable: Species

Mann Whitney U Test comparison of means on the carapace weights of male and female blue crabs

Gender N Mean Rank Sum of Ranks

Male 33 29.35 968.50

Blue_Crab_Weight Female 17 18.03 306.50

Total 50

Test Statisticsa

Blue_Crab_Weight

Mann-Whitney U 153.500

Wilcoxon W 306.500

Z -2.614

Asymp. Sig. (2-tailed) .009

Exact Sig. (2-tailed) .008

Exact Sig. (1-tailed) .004

Point Probability .000 a. Grouping Variable: Gender

T-Test comparison of means on the weights of male and female hairy crabs

Gender N Mean Std. Deviation Std. Error Mean

Male 21 195.2381 45.66799 9.96557 Hairy_Crab_Weight Female 29 161.3448 45.65341 8.47763

Independent Samples Test

Hairy_Crab_Weight Levene's Test t-test for Equality of Means for Equality of Variances

F Sig. t df Sig. (2- Mean Std. Error 95% Confidence Interval tailed) Difference Difference of the Difference

Lower Upper

Equal variances .461 .500 2.591 48 .013 33.89327 13.08300 7.58813 60.19840 assumed

Equal variances not 2.590 43.244 .013 33.89327 13.08368 7.51182 60.27472 assumed

Mann Whitney U Test comparison of means between the weights of blue and hairy crabs

Species N Mean Rank Sum of Ranks

Blue Crab 50 51.02 2551.00

Crab_Weight Hairy Crab 50 49.98 2499.00

Total 100

Test Statisticsa

Crab_Weight

Mann-Whitney U 1224.000

Wilcoxon W 2499.000

Z -.180

Asymp. Sig. (2-tailed) .857

Exact Sig. (2-tailed) .859

Exact Sig. (1-tailed) .430

Point Probability .001 a. Grouping Variable: Species