Capture, Transport & Storage

Every year billions of animals like crabs, lobsters, prawns and crayfish (decapod crustaceans) are captured and transported around the world by sea, air and land for commercial purposes. Throughout the journey from sea to plate, they go through three key stages, capture, transport and storage, each of which have their own set of stressors.

  

From capture onwards, decapods face numerous welfare issues, including: 

  • Damage and injury 

  • Inappropriate conditions – water quality, salinity, humidity, temperature, pressure changes 

  • Air exposure 

  • Disturbances – vibrations, light, noise 

  • Unsuitable packaging, stacking and compression 

  • High stocking densities – confinement and overcrowding 

  • Mixing of species 

  • Starvation, fasting, and dehydration 

  • Lack of shelter 

  • Handling 

  • Restricted movement – claw immobilisation, muscle loss 

  • Stress and exhaustion

Welfare Issues

Despite their hard shells, these fragile animals are at risk of physical trauma and injuries caused by capture methods. Being hauled up from the sea floor to fishing vessels causes a rapid change in environmental conditions, including suddenly changing pressure and temperature. They are also exposed to the air, and as aquatic animals that breath underwater using gills, this exposure disrupts oxygen consumption. Air exposure in decapods is associated with increased vulnerability to disease, induces as stress response, and increases the likelihood of death (1)(2)(3)(4)(5)(6)(7). 

Decapods are kept without food before travel to reduce waste products building up during the journey (1). They are also transported and stored alongside many other animals, sometimes of different species, with very little room. The hunger and dehydration combined with high stocking densities has been found to lead to aggressive behaviour and cannibalism (8)(9). In the wild, decapods tend to be solitary and territorial, so this proximity to other animals is extremely stressful for them (10)(11)(12). 

How the animals are packed, for example at the top or bottom of the transport tank, has a significant impact on their journey. Those at the bottom are more likely to lose limbs and have a reduced chance of surviving the journey due to compression and suffocation under the weight of those above (13). As well as this, they will be exposed to disturbances, such as road vibrations and noise. During all three stages, decapods are unable to express natural behaviour. They have their claws bound, which restricts movement and can cause loss of muscle as they may be stored in this way for months (14)(15).

Pacific White shrimps or Litopenaeus vannamei on hand in front of the aquaculture pond, Fr
Bound brown crab 3.jpeg

Recommendations

It is clear that basic welfare standards are not being met from capture to consumption.

We are calling for the establishment of legal codes of practice which meet species-specific welfare needs for decapod crustaceans during capture, transport and storage. Furthermore, live transports should be replaced as far as possible by the transport of meat and carcasses to minimise the number of animals subjected to transport processes.

References

  1. Fotedar, S., & Evans, L. (2011). Health management during handling and live transport of crustaceans: a review. Journal of invertebrate pathology, 106(1), 143-152. 

  2. Dong, Z., Mao, S., Chen, Y., Ge, H., Li, X., Wu, X., ... & Zhang, Q. (2019). Effects of air-exposure stress on the survival rate and physiology of the swimming crab Portunus trituberculatus. Aquaculture, 500, 429-434. 

  3. James, P., Izquierdo‐Gómez, D., & Siikavuopio, S. I. (2019). Use of reflex indicators for measuring vitality and mortality of the snow crab (Chionoecetes opilio) in captivity. Aquaculture research, 50(4), 1321-1328. 

  4. Barrento, S., Marques, A. Vaz-Pires, P. and Nunes, M.L. (2011). Cancer pagurus (Linnaeus, 1758) physiological responses to simulated live transport: Influence of temperature, air exposure and AQUI-S. Journal of Thermal Biology 36, 128–137. 

  5. Barrento, S., Marques, A., Vaz‐Pires, P., & Nunes, M. L. (2012). Physiological changes during simulated live transport of Cancer pagurus and recovery in holding tanks. Aquaculture Research, 43(10), 1415-1426. 

  6. Fotedar, S., Tsvetnenko, E., & Evans, L. (2001). Effect of air exposure on the immune system of the rock lobster Panulirus cygnus. Marine and Freshwater Research, 52(8), 1351-1355. 

  7. Raicevich, S., Giomi, F., Pranovi, F., Giovanardi, O., Di Muro, P., & Beltramini, M. (2011). Onset of and recovery from physiological stress in Liocarcinus depurator after trawling and air exposure under different seasonal conditions. Hydrobiologia, 664(1), 107-118. 

  8. Wickins J.F. & Lee O.C. (2002). Crustacean farming. Blackwell Science Ltd., Oxford, UK. 446 pp. 

  9. Siikavuopio, S. I., Johansson, G. S., James, P., & Lorentzen, G. (2019b). Effect of starvation on the survival, injury, and weight of adult snow crab, Chionoecetes opilio. Aquaculture Research, 50(2), 550-556. 

  10. Beard, T. W., & McGregor, D. (2004). Storage and care of live lobsters. Laboratory Leaflet (Revised), 66 (66), 1–27. 

  11. Carder, G. (2017). A preliminary investigation into the welfare of lobsters in the UK. Animal Sentience: An Interdisciplinary Journal on Animal Feeling, 2(16), 19. 

  12. Bennison, S. (2000). Guidelines on Aquatic Animal Welfare for the Aquaculture Industry in Western Australia. ACWA. 

  13. Barrento, S., Marques, A., Vaz-Pires, P., & Nunes, M. L. (2010). Live shipment of immersed crabs Cancer pagurus from England to Portugal and recovery in stocking tanks: stress parameter characterization. ICES Journal of Marine Science, 67(3), 435-443. 

  14. Esposito, G., Nucera, D., & Meloni, D., 2018. Retail Stores Policies for Marketing of Lobsters in Sardinia (Italy) as Influenced by Different Practices Related to Animal Welfare and Product Quality. Foods 7(7), 103. Chicago. 

  15. D’Agaro, E., Sabbioni, V., Messina, M., Tibaldi, E., Bongiorno, T., Tulli, F., Lippe,G., Fabbro, F. and Stecchini, M., 2014. Effect of confinement and starvation on stress parameters in the American lobster (Homarus americanus). Italian Journal of Animal Science 13, 891-896.