64
The sex of a crab can be easily determined. Females have a large abdomen, while
males are narrower. Males are larger than females of the same size. The mating is
carried out in the summer months and in the waters close to the shore while the
females are still in the soft shell immediately after the shell change. For 2 weeks
prior to shell replacement, male crabs are accompanied by hard-shell males.
Spawning occurs immediately after the females discard the shell. Maturing of most
of the females in July August spawn in November of the same year. However, in
some cases, ovulation is delayed until next winter. Crabs usually choose soft sea
bottoms to spawn. They often choose deep water. The eggs are kept in the abdomen
of the crab for about 7 months. The number of eggs carried can vary from half a
million to three million. In the spring and summer following the ovulation, the
females move to the coastal waters where the eggs hatch (Edwards and Early 1978).
2.2.2.2 Trade and Marketing of Crabs
According to FAO (2016) report, the world fishery crabs’ production is primarily
comprised of Scylla serrate, Scylla olivacea, Portunus pelagicus, and Callinectes
sapidus. Production has increased from 343 thousand t, in 1990, to more than
951,000 t, in 2015. China accounts for 71.9% of the world annual production
(684,400 t), followed by Indonesia (77,700 t), USA (72,400 t), and Philippines
(27,200). However, precise information of the global production is limited as most
production systems are small-scale or family-owned, and when carried out on an
industrial scale, there is usually no interest in the disclosure of data or, very often,
trade secrets are involved. This difficulty limits the knowledge about real production
data and often leads to the underestimation of the total amount produced (Hungria
et al. 2017).
According to the FAO-Globefish (2019a, b) report, global imports of crab (all
types) increased slightly in 2018, to 405,400 tonnes. Imports into the United States
of America dropped by 3.3% to 104,400 tonnes, while Chinese imports grew slightly
to 81,900 tonnes. Imports into the Republic of Korea also grew, from 45,400 tonnes
to 50,100 tonnes. Shipments to the United States of America dropped from Canada
and increased from the Russian Federation. Russian Federation crab exports
increased by almost 10%, and the main markets were the Republic of Korea (43,000
tonnes or 61% of the total), the Netherlands (12,800 tonnes or 18% of the total) and
China (11,500 tonnes or 16% of the total). China’s crab exports fell slightly to
72,600 tonnes in 2018, from 75,000 in 2017. The main markets were the Republic
of Korea, the United States of America, and Taiwan Province of China (FAOGlobefish 2019a).
Indonesia is the main supplier of blue swimming crab to the US market, but landings in Indonesia have been flat. In 2017, the United States of America imported a
total of 26,300 tonnes. Indonesia shipped 46% of this volume, while China supplied
14% and the Philippines 12%. During the first 9 months of 2018, the United States
of America imported 20,200 tonnes of blue and red swimming crab, around 6.8%
2 Crustacean Shellfish
The sex of a crab can be easily determined. Females have a large abdomen, while
males are narrower. Males are larger than females of the same size. The mating is
carried out in the summer months and in the waters close to the shore while the
females are still in the soft shell immediately after the shell change. For 2 weeks
prior to shell replacement, male crabs are accompanied by hard-shell males.
Spawning occurs immediately after the females discard the shell. Maturing of most
of the females in July August spawn in November of the same year. However, in
some cases, ovulation is delayed until next winter. Crabs usually choose soft sea
bottoms to spawn. They often choose deep water. The eggs are kept in the abdomen
of the crab for about 7 months. The number of eggs carried can vary from half a
million to three million. In the spring and summer following the ovulation, the
females move to the coastal waters where the eggs hatch (Edwards and Early 1978).
2.2.2.2 Trade and Marketing of Crabs
According to FAO (2016) report, the world fishery crabs’ production is primarily
comprised of Scylla serrate, Scylla olivacea, Portunus pelagicus, and Callinectes
sapidus. Production has increased from 343 thousand t, in 1990, to more than
951,000 t, in 2015. China accounts for 71.9% of the world annual production
(684,400 t), followed by Indonesia (77,700 t), USA (72,400 t), and Philippines
(27,200). However, precise information of the global production is limited as most
production systems are small-scale or family-owned, and when carried out on an
industrial scale, there is usually no interest in the disclosure of data or, very often,
trade secrets are involved. This difficulty limits the knowledge about real production
data and often leads to the underestimation of the total amount produced (Hungria
et al. 2017).
According to the FAO-Globefish (2019a, b) report, global imports of crab (all
types) increased slightly in 2018, to 405,400 tonnes. Imports into the United States
of America dropped by 3.3% to 104,400 tonnes, while Chinese imports grew slightly
to 81,900 tonnes. Imports into the Republic of Korea also grew, from 45,400 tonnes
to 50,100 tonnes. Shipments to the United States of America dropped from Canada
and increased from the Russian Federation. Russian Federation crab exports
increased by almost 10%, and the main markets were the Republic of Korea (43,000
tonnes or 61% of the total), the Netherlands (12,800 tonnes or 18% of the total) and
China (11,500 tonnes or 16% of the total). China’s crab exports fell slightly to
72,600 tonnes in 2018, from 75,000 in 2017. The main markets were the Republic
of Korea, the United States of America, and Taiwan Province of China (FAOGlobefish 2019a).
Indonesia is the main supplier of blue swimming crab to the US market, but landings in Indonesia have been flat. In 2017, the United States of America imported a
total of 26,300 tonnes. Indonesia shipped 46% of this volume, while China supplied
14% and the Philippines 12%. During the first 9 months of 2018, the United States
of America imported 20,200 tonnes of blue and red swimming crab, around 6.8%
2 Crustacean Shellfish