Blue Crab Fishery Research Articles

Fishing impact of blue swimming crab (Portunus pelagicus) fishery on target in Lamongan Water, Northern Coast of Eastern Java Province

Blue swimming crab (Portunus pelagicus) is a high-value export commodity of fisheries to the international market. Thus, it promotes overfishing, reducing target stocks, and ecological impact on non-target biota. Fishers in Lamongan Regency use traps, trammel nets, and mini trawl (arad) to target the crabs. The fishing gears have different levels of selectivity. This study aims to evaluate the impact of crab fishing on target (P. pelagicus), particularly in the study area. The samples of blue swimming crab (BSC) were collected using the quota sampling method. The parameters of the crab catch (Portunus pelagicus) collected included carapace width, weight, sex, and gonad maturity stage (GMS). 1424 fishing vessels and 3598 fishers targeted the BSC in the Lamongan water. The result of this study showed that 93% of BSC catch was higher than the legal size from traps, 66% (arad), 89 % (trammel nets). The growth parameter of L∞ = 156.95 mm (for female) and L∞ = 182.22 mm (male), while K = 1.4 per year (for female) and K = 1.4 per year (male). The relationship between carapace width and weight of the male and female crabs was positive allometric growth. The LB-SPR parameter value was 23% which indicated that the crab resource stock in Lamongan waters was a ‘fully-moderately’ status, while the selectivity level indicated an ‘over-exploitation’ base on the E value = 0.69 (for female crab) and E = 0.72 (for male). This study proposes urgently reducing the fishing effort targeting BSC, particularly by the mini trawl (arad) and implementing a rebuilding stock program for the BSC.

Diversity of Crustaceans Bycatch of Blue Swimming Crab (Portunus pelagicus) Fisheries of Landed in Leppe village, Soropia District, Konawe Regency

This research was aiming of find out the diversity of crustaceans bycatch of blue swimming crab (Portunus pelagicus) fisheries of moon period based. The method used was a survey method and sampling of crustacean bycatch was carried out during the period of bright moon (11-15 moon nights) and dark moon (27-1 moon nights). The results showed that there were 20 species of crustacean bycatch found during the study in which 17 species were found during the bright moon and 16 species were found during the dark moon. Thalamita danae species had the highest abundance during the dark and the bright moon period. The number of the male crustaceans bycatch was higher than the females for both bright and dark moon periods.Diversity index crustacean bycatch in both periods (brigh tand dark) ranged from 0.83 to 0.85. The evennes index and dominance index inthe bright and dark moon are the same (0.69 and 0.22, respectively).

Lost Gear on Blue Swimming Crab Fisheries in Banten Bay: Case of Abandoned, Lost or Discarded Fishing Gear

Blue swimming crab is one of the capture fisheries sector leading commodities in Banten Bay which is caught using gill nets and collapsible traps. The risk of lost fishing gears during operation is very high, both due to the bad weather and interactions with other fishing gear. The Abandoned, Lost or Discarded Fishing Gear (ALDFG) contributes significantly to the abundance of marine plactics in the world which has a negative impact on the sustainability of fish resources, water quality and endangers the safety of navigation. Nevertheless, there have been no mitigation activities and efforts to reduce ALDFG in the Banten Bay. This study aims to identify the global causes of lost fishing gear derived from blue swimming crab fisheries in Banten Bay. Data were collected around the Archipelagic Fishing Port (PPN) of Karangantu in May-June 2022. In-depth interviews were conducted with 28 respondents who were selected purposively and the results were analyzed descriptively. The results showed that generally, the causes of lost gear were conflicts with other fishing gear which constitute 64%, whilst human errors during fishing operations and bad weather contributed 19% and 17%, respectively. Keywords: ALDFG, conflict, blue swimming crab, lost gear.

Spawning and Reproductive Potential of Blue Swimming Crab (Portunus pelagicus) at Spermonde Archipelago, Indonesia

The problem in the management of blue swimming crab (BSC) fisheries is a decrease in stock that overlaps with an increase in fishing activities. This study aimed to analyze the ratio of spawning potential (SPR), reproductive potential, and reproductive productivity of BSCs taken from the Spermonde Islands. Spawning potential was analyzed using SPR, while reproductive potential analysis used the relative proportion of data between female, berried female and the average fecundity of each class size. The results showed that the BSC in Spermonde were growth overfishing and recruitment overfishing. The SPR of the BSC was estimated to be 7%, below the biological reference point. The highest reproductive potential index of berried females occurred in the group with a carapace width of 111-120 mm which contributed 36.84% of the total egg production. The value of reproductive productivity was 1.35 indicating a productive population. Current legislation allows the capture of BSCs with carapace sizes larger than 100 mm. Based on the data of this study, this size limit has the potential to eliminate 65.92% of the total egg production in the Spermonde Islands. To ensure the sustainability of BSCs in the Spermonde Islands, it is necessary to limit size by capturing BSCs >120 mm to protect the berried female and increase total egg production.

Perceptions of compliance in recreational fisheries: Case study of the Peel-Harvey blue swimmer crab fishery

Effective recreational fisheries management requires a balance between fisher enjoyment and compliance with regulations and fisher perceptions can be useful to understand whether the balance is right. Our study collected fisher insights via an online perceptions survey into compliance within the recreational shore-based Peel-Harvey blue swimmer crab fishery in Western Australia. Overwhelmingly, participants self-reported as complying with regulations; a positive finding for a licence-free fishery. Further, to enable increased quantity and size of available stock and thus overall enjoyment of the fishery, survey participants suggested longer fishery closure periods; harsher noncompliance penalties; more natural and physical surveillance; and greater educational signage in popular fishing areas. These insights challenge existing literature whereby tough regulations are often rejected by fishers and may lead to noncompliance. In a view to achieve a shared goal of a sustainable fishery, we explore survey perceptions against situational crime prevention to optimize compliance, embracing regulator-led ‘cooperative compliance’ outcomes. Our results are useful not only to this fishery but apply more broadly to other fisheries within and beyond Western Australia.

Dampak Pandemi Covid-19 pada Kelayakan Usaha Perikanan Rajungan di Teluk Banten

The Archipelagic Fishing Port of Karangantu located in Banten Bay is one of the blue swimming crab fishing centers in the Java Sea. Covid-19 pandemic had significant effect on blue swimming crab fisheries in Karangantu, especially on the increasing of fishing operational cost, decreasing of price, and limited acces for market distribution. This study aims to analyse the feasibility of blue swimming crab fisheries activity using bottom gillnet in Banten Bay after Covid-19 pandemic. The research was conducted in May-June 2021 in Karangmulya Village, Kasemen District, Serang City with a total of 22 respondents. The data were collected using deep interview with each respondent who was selected purposively. The analysis of business feasibility was conducted based on the parameters of the ratio between income and costs (R/C), payback period (PP), and net present value (NPV). The results show the Covid-19 induced the decreasing of R/C ratio value from 2.08 before to 1.81 after Covid-19 pandemic, respectively. The value of PP also increased from 0.65 years to 0.68 years. Moreover, the potential profit of blue swimming crab fishing also decreased from IDR 55 million before Covid-19 to IDR 52 million after Covid-19 pandemic. However, due to the positive NPN value, the blue swimming crabs fishing actvity using bottom gill nets in Banten Bay is still feasible to be developed. Keywords: blue swimming crab, Covid-19, impact, fisheries

Reproductive Biology and Feeding Ecology of The Blue Swimming Crab (Portunus pelagicus) in Northern Coastal Waters, Sri Lanka.

Blue swimming crab (Portunus pelagicus) fishery has emerged to become an important export-oriented fishery in Sri Lanka over a decade and recently resulted in a rapid increase in the exploitation. The present study attempts to understand the reproductive biology and feeding ecology of blue swimming crab which will be vital in the management of capture fishery. Five major landing sites in the Jaffna district in Northern Sri Lanka, where blue swimming crab is frequently landed throughout the year were selected for the study. Biological parameters relating to sex, carapace width, body weight, maturity, and egg sac colour with egg sac weight were recorded at the field from November 2014 to October 2015. Randomly selected crab samples were brought to the laboratory and analysed for their maturity stages, length at first maturity, Gonadosomatic Index, fecundity, and gut contents. The study revealed that male crabs mature at a smaller size than females. The sex ratio varied greatly with time and males were always dominant in the catch. The blue swimming crabs in the Northern waters of Sri Lanka spawn throughout the year, with two spawning peaks in February and May. The total fecundity of ovigerous blue swimming crab increased with increased carapace width and body weight and it ranged from 123,482 to 3,179,928 eggs, with an average of 884,982 ± 676,420. A remarkably higher percentage of empty stomachs were observed under the present study in both mature and immature crabs and this could be due to lack of food availability in the environment and different digestibility rates of food items. The diet of blue swimming crab is highly variable reflecting the ability to adopt to different modes of feeding.

Population dynamics of blue crab (<i>Paralithodes platypus</i> Brandt, 1849) in the northwestern Bering Sea

State of the blue crab stock and production is considered for the Russian sector of the Bering Sea on the data of bottom trawl and trap surveys conducted by TINRO in 2005–2017 and fishery statistics. The commercial stock was assessed for 2018 by cohort analysis. The absolute majority of commercial males within the West Bering Sea fishing zone concentrated in two areas located at Koryak coast and at Cape Navarin, whereas the commercial aggregations were absent in the Olyutorsky Bay and Karaginsky Bay. The stock distribution between these two areas was unstable; recently the aggregation at Koryak coast increased to 72 % of the total number of commercial males in 2017. This dynamics is conditioned by both changes in reproduction and intensity of fishery. The total commercial stock of blue crab had increased since 2014 and reached the maximum of 18.133 × 106 ind. (males) in 2017 that exceeded significantly the level of 2005–2013. The blue crab fishery extends in the Bering Sea, since 2010 the portion of used TAC increased from approximately 93 % in 2011–2015 to 98 % in 2016–2017 and 99 % in 2018. State of the population is evaluated as satisfactory and stable.

Assessing Northeast Florida Offshore Blue Crab Fishing Effort within Florida’s State Waters

AbstractDuring the winter months, commercial fishery effort targeting blue crabs Callinectes sapidus increases in the offshore Atlantic waters of northeast Florida as crabbers follow the seasonal migration of female blue crabs. The present study sought to describe offshore commercial fisher behavior through a mail survey (2020) and to characterize fishing effort using landings data (from 2009–2010 to 2019–2020) and an aerial survey from January to March (2021). Offshore fisher effort (i.e., number of participants and landings) varied each winter, and the effort was greatest in the winters of 2011–2012 and 2018–2019. The number of participants that reported offshore landings ranged from 6 to 11. Offshore landings accounted for 2.6% of the total landings in northeast Florida and were correlated with a decrease in inshore landings. The mail and aerial surveys determined that crab traps were concentrated off two sections of the coast within 1.61 km (1 mi) of shore: (1) from Vilano Beach to south of Ponte Vedra Beach and (2) between Neptune Beach and Atlantic Beach. Participants in the mail survey reported fishing a median of 150 traps (range = 50–400 traps), while aerial counts estimated an average ± SD of 59.5 ± 5.4 traps/crabber. Average trap counts from the aerial survey during the winter of 2020–2021 suggested that 9.33 km (5.8 mi) of vertical line were used within the survey area. This study successfully characterized the northeast Florida offshore blue crab fishery as a small but valuable fishery for a few crabbers, with effort driven by seasonal demand and crab availability.

Differential Effects of Three Crab Trap Escape Ring Sizes on Retention of Male and Female Blue Crabs

AbstractThe blue crab Callinectes sapidus supports a valuable commercial fishery in Texas waters. Several regulatory tools are used to manage the catch of blue crabs, including the use of escape rings, which are designed to allow for the escapement of undersized individuals. In this study, we first examined the relationship between carapace width (CW) and carapace length (CL) for male and female blue crabs (with an eye toward the effectiveness of the escape rings). Second, we examined the retention rates for male and female blue crabs across a range of CWs for three different escape ring sizes: 60.3 (current Texas minimum escape ring size), 63.5, and 66.7 mm. Male crabs were found to have a greater CL at a given CW than did female crabs, and this discrepancy between the sexes increased at larger CWs. Assuming that CL is the primary determinant in crab trap retention, this would suggest that males are typically retained at a smaller CW than females and this discrepancy at size of retention increases for larger escape rings. This interpretation was validated in the retention analyses for the three escape ring sizes examined in this study. Overall, the carapace width at 50% retention (CW50) increased with increasing escape ring size for each sex and the discrepancy between CW50 for male and female crabs increased from 4.4 mm (60.3‐mm ring) to 5.0 mm (63.5‐mm ring) to 7.2 mm (66.7‐mm ring). The probability of retention is given for a range of potential minimum CWs (127, 140, and 152 mm) for each escape ring size. Fishery managers should select appropriate escape ring sizes given the target legal minimum CW for the blue crab fishery and also consider the differential performance of these escape ring sizes between sexes when using crab trap escape rings as a management tool.

Status and Management of the Blue Crab Fishery in the Gulf of Mexico

AbstractManagement of the blue crab Callinectes sapidus fishery in the Gulf of Mexico is the responsibility of the individual states under the purview of a regional management plan. States generally follow the “2‐S” system of management, placing emphasis on size and sex. Despite management policies, harvest and juvenile abundances remain in decline. A significant trend toward decreasing harvest began in the early 2000s, with landings below average in 13 of the 20 years from 2000 to 2019. Since 2010, the fishery has maintained a lower but relatively stable harvest. There have been significant decreases in numbers of late‐stage juveniles in fishery‐independent trawl surveys, while numbers of megalopae and early juveniles have not exhibited declines. Postsettlement mortality is potentially driven by climate‐related hydrological processes that structure the biotic community (predator guild) and nearshore habitats. Diversity of predators, few predation‐free refuges, and a lack of seasonality in predation likely contribute to high regional mortality. Factors that influence quality and quantity of available refuge may ultimately control abundance. Although genetics data describe the population as panmictic, geographic differences in coastal climate and hydrological processes may act to structure populations. Separation of stocks according to ecozones may provide a more suitable approach to population delineation. The 2011 stock assessment divided the population into eastern and western regions based on confounding information on genetics, physiographic features that limit larval transport, variations in climate, and migration of female crabs along the west coast of Florida. There is concern that the population is undergoing Gulf of Mexico‐wide changes in biomass associated with regional climate regime shifts that may alter the resiliency of the stock. Whether the shift to a more favorable climate phase would reverse the declining trends is unknown. Changes in population levels could be rapid given the high juvenile mortality and short generation time as well as the importance of climate in structuring habitat.

A reflex action mortality predictor (RAMP) for commercially fished blue crab Callinectes sapidus in Florida

The paucity of data on discard mortality in the commercial blue crab fishery contributes significant uncertainty to stock assessments. The reflex action mortality predictor (RAMP) method is used to predict mortality of commercially fished species by establishing a relationship between reflex impairment and the likelihood of mortality (RAMP curve). The present study adapted the RAMP method to commercially fished blue crabs in two unique habitats in Florida, the Tampa Bay estuary and the St. Johns River. The euryhaline nature of blue crabs permits the fishery to operate in myriad habitats, which adds complexity to cumulative effects that influence discard mortality. A total of 697 crabs were assessed, and a RAMP curve was generated. Logistic regression analyses determined that reflex impairment score, injury score, and salinity are strong predictors of discard mortality, with 91% of predictions correct. For every 1-unit increase in reflex impairment and injury score, mortality was 2.71 and 1.65 times more likely, respectively. Additionally, for every 1-SD (11.35 ppt) increase in salinity, mortality was 2.17 times more likely. Crab size, sex, water temperature, and emersion time minimally influenced mortality. The present study is the first crustacean RAMP research that included water quality and demonstrated that its inclusion increases the predictability of discard mortality. The RAMP curve can be used as a tool to estimate discard mortality aboard commercial vessels and discard mortality in future stock assessments.

The coral reef health at surrounding blue swimming crab fishery sites in Mandangin Island, East Java, Indonesia

Blue swimming crab fishery activities very often do not put into account the environmental condition. Coral reef, as one of the blue swimming crab habitats, can be affected by these activities. This study aims to determine the effect of blue swimming crab fisheries on coral health in Mandangin Island, East Java, Indonesia. Data collection points are determined based on the results of interviews by participatory mapping. Water quality data includes visibility, temperature, salinity, pH, DO, current velocity. Collecting coral reef data were using Line Intercept Transect (LIT), while for reef fish Underwater Visual Census (UVC) were used. The coral health index was determined based on the relevance between benthic components and fish components. The average of Mandangin Island’s water quality is in accordance with the quality standards of the Indonesian Minister of Environment Decree No.51 of 2004. Hard coral cover and fish biomass are classified as low, but the value of resilience is high. The coral reef health index value on Mandangin Island is 3.

Fishery Biology and Population Structure of the Blue Swimmer Crab, Portunus pelagicus, from the Red Sea, Egypt

More than 300 MT of blue swimmer crabs (BSC), Portunus pelagicus, are annually captured from the fisheries of the Egyptian Red Sea waters. During the last 20 years, a decline has been witnessed in the production of this species. For management purposes, information about the fishery's biology and population structure is required. Hence, monthly samples of P. pelagicus were collected from the commercial catch of Hurghada landing site, Red Sea, Egypt during the period from November 2017 to October 2018. A number of 1190 specimens were measured for morphometric relationships, sex ratio, age determination using carapace width frequency, population structure, mortality rate and exploitation ratio. The study revealed that P. plagicus was targeted by trammel nets and caught by a small bottom trawler as a by-catch. Carapace width- total weight relationship showed positive allometric growth (b-value= 3.10). Higher condition factors were observed in the small individuals. Four age groups were determined and age group +I was dominant by number (60.6%). Parameters of the von Bertalanffy equation were 21.19 cm, 0.414 year-1, and -0.998 year for CW∞, K and to, respectively. The carapace width at first capture was estimated (CW50 = 8.7 mm). The mortality rates were calculated as 2.929, 1.285 and 1.644 year-1 for total, natural and fishing mortalities, respectively. The blue swimmer crab fisheries on the Red Sea is over-exploited (E= 0.65) by the trammel net. Some management measures were suggested to maintain its stock for sustainability.

More for less: Citizen science supporting the management of small-scale recreational fisheries

While many global fisheries rely on commercial catch and effort statistics to inform stock assessments and management, alternative approaches are required for small-scale recreational fisheries. In this study, a citizen science program was implemented to collect recreational catch and effort and fishery-independent data using three Western Australian blue swimmer crab (Portunus armatus) fisheries as case studies. Between 2013 and 2019, an opt-in Research Angler Program (RAP) was supported by 102 diarists submitting data from 1,705 fishing events, with direct and regular contact proving important for maintaining participation. Representing the only current recreational crabbing information for the three fisheries, the RAP data proved valuable in assessing management options (e.g. increases in size limits, bag limit reductions, seasonal closures) during a recent review of the Western Australian P. armatus resource. Two follow-up surveys to canvass diarist attitudes towards the program identified a desire to contribute to research and management, and concerns about fish stocks, as key motivations for involvement. In addition, 26 diarists assisted with fishery-independent breeding stock surveys (FIS) to collect valuable stock assessment data. The RAP and FIS proved complementary, as the first provided useful spatial/temporal coverage of catch rates and catch composition, while the second gave a targeted assessment of breeding stock abundance. We demonstrate how the data can generate annual fishery performance indices, such as standardised recreational catch rates and a fishery-independent egg production index, to support a potential harvest strategy. This study highlights a cost-effective and highly valuable citizen science approach to obtain key information for the assessment and management of small scale recreational fisheries, with suggested recommendations for researchers considering a similar approach elsewhere.

The influence of blue crab movement on mark–recapture estimates of recreational harvest and exploitation

Despite the need to quantify total catch to support sustainable fisheries management, estimating harvests of recreational fishers remains a challenge. Harvest estimates from mark–recapture studies have proven valuable, yet animal movements and migrations may bias some of these estimates. To improve recreational harvest estimates, explore seasonal and spatial harvest patterns, and understand the influence of animal movement on exploitation rates, we conducted a mark–recapture experiment for the blue crab (Callinectes sapidus) fishery in Maryland waters of Chesapeake Bay, USA. Data were analyzed with standard tag-return methods and with revised equations that accounted for crab movement between reporting areas. Using standard calculations, state-wide recreational harvest was estimated to be 4.04 million crabs. When movement was included in the calculations, the estimate was 5.39 million, an increase of 34%. With crab movement, recreational harvest in Maryland was estimated to be 6.5% of commercial harvest, a finding consistent with previous effort surveys. The new methods presented herein are broadly applicable for estimating recreational harvest in fisheries that target mobile species and for which spatial variation in commercial harvest is known.

Morphometric Relationships in the Blue Swimming Crabs, (Portunus pelagicus) (Linnaeus, 1758) from the Palk Bay, Sri Lanka

The blue swimming crab (Portunus pelagicus) has become the focus of an important export-oriented fishery in Sri Lanka for a decade. The Palk Bay in the Northern coastal waters of Sri Lanka is one of the best-known fishing grounds for blue swimming crabs in Sri Lanka. This study was undertaken with the aim of establishing some morphometric relationships for P. pelagicus in the Palk Bay.
 Biological sampling was conducted for five consecutive days per month from November 2014 - October 2015 in the Northern landing sites in the Jaffna District where the catch of Palk Bay blue swimming crab fishery was landed. P. pelagicus specimens were also randomly collected for laboratory analysis. The morphometric measurements of the specimens for the following parameters were undertaken: CW - carapace width with the spine, CWW - carapace width without spine, MW – mouth width, TL - total length, LCPL - left chelar propodus length, LMOV - left movable part Length, RMOV - right movable part length, LCPH - left chelar propodus height, RCPH - right chelar propodus height, ABW - abdominal width, ABL - abdominal length and BW - body weight. The least squared method was used to obtain the Length-Length (L-L) and Length-Weight (L-W) relationships.
 Of the 65 L-L relationships obtained for P. pelagicus from the study, 34 relationships were correlated (r2>0.5). The estimated relationships between BW and CW for males and females were BW=0.0001 CW 3.01 (r2 =0.84) and BW= 0.0001 CW 2.90 (r2 =0.86), respectively.
 Positive allometric growth was observed for male P. pelagicus, whereas a negative allometric growth was observed for female P. pelagicus. Most of the morphometric relationships of P. pelagicus obtained in this study were not isometric.

Spatial and Temporal Distribution of Blue Swimming Crab Larvae (Portunus pelagicus) in The Conservation Area of Betahwalang, Central Java

Betahwalang has been one of the main contributors to the Blue Swimming Crab (BSC, Portunus pelagicus) fisheries production in Central Java Province. Recruitment of the BSC depends to a large extend on the abundance of crab larvae. However, information on larval distribution of the crab affecting the recruitment to the fishery, fishery management and decision making to support crab conservation in Betahwalang area has been lacking. The purpose of this study is to describe the spatial and temporal distribution of BSC larvae in the crab conservation area, to identify the larval stage most commonly occurs in the conservation area, and to develop process of decision making to managing conservation areas. This study was conducted in twelve months, starting from January until December 2018. The spatial distribution of the crab larvae was analyzed and mapped by means of SPSS and ArcGIS. The results of this study indicate that the crab larvae occur in the conservation area throughout the year. The highest larval abundance of the crab occurs in May, September, and November. The most commonly found crab larval stages were megalopa. As megalopa and crablet stages are relatively much more active and closer to the adult form, their occurrence in the conservation area and throughout the year of 2018 suggests the existence of continuous support to the Blue Swimming Crab recruitment for the following year. The spatial and temporal distribution of the larvae were influenced by oceanographic parameters including temperature, nitrate and phosphate, which were associated with monsoonal changes in the Java Sea.

Who You Speak to Matters: Information Sharing and the Management of a Small-Scale Fishery

Sustainable natural resource management requires collaboration, adaptability and coordination between science, policy and stakeholders. Communication of scientific information through social networks is integral to effective governance. This study employed social network analysis to investigate information flow between stakeholders associated with the blue swimmer crab (Portunus armatus) fishery in the Peel-Harvey Estuary, south-western Australia. Although the fishery received Marine Stewardship Council certification in 2016, a preliminary study conducted between 2017 and 2018 revealed that fishers were concerned about its status and management. Consequently, 85 face-to-face interviews were conducted with commercial and recreational fishers, academics, government bodies, representatives of fishing organizations, non-governmental organizations, and tourism organizations to understand the flow of information and the influence on perceptions of sustainability. The results showed that: i) Few individuals were key for sharing information within and between different organizations forming the fishery network and only two of the six groups (government bodies and the commercial fishing sector) were highly connected and appeared as key for information sharing; ii) After the public sector stakeholders, academic groups were the second-least connected, despite having actively researched the Peel-Harvey Estuary and the P. armatus fishery for over 40 years; iii) Recreational fishers exchanged information mainly with other fishers and the regional fisheries department, rather than the organization representing recreational fishers; iv) Modes of communication used with the recreational fishing sector greatly differed between the fisheries department (i.e., mainly via phone/email) and the recreational fishing organisation (i.e., strong online presence, social media and phone/email); v) Issues of inclusiveness and representation were highlighted for some of the groups and organizations. This study has identified logistical and institutional difficulties to communicate information regarding the science, management and environmental issues related to a small-scale crab fishery, providing managers and other stakeholders with a pathway of action for enhancing resource management.

Stock Status of Blue Swimming Crab (Portunus pelagicus Linnaeus, 1758) in Tiworo Strait Waters, Southeast Sulawesi, Indonesia

The blue swimming crab (BSC) fishery in Tiworo Strait has been heavily exploited since two decades ago when its worldwide demand and price was very high. Study on population aspects of this organism in this waters is limited. The aim of present study was to investigate growth patterns, population stock status, and size at first gonad maturity of Portunus pelagicus. One of the main fishing ground of BSC around Tiworo Strait waters is at Bangko and Gala Islands. Samples of BSC were taken monthly using gillnet and collapsible trap. Each sample taken was identified its sex, measured its carapace width, and weighed. Data collected from fishing ground of BSC were analyzed to find out growth patterns, population stock status using spawning potential ratio (SPR) method, and the first gonad maturity (CW50). The results of study showed that growth patterns of BSC male and female following isometric growth patterns (b=0) (P<0.05). It was found out that SPR of BSC from both fishing ground was 22.46% and 23.71%, respectively which indicates that population stock status of BSC in Tiworo strait waters is “moderate level” (SPR > 20%). The size at first gonad maturity (CW50) was attained at carapace width of 9.16 cm for male and 10.16 cm for female. Those imply that BSCs allowed to be caught should be >10 cm.