Krill and shrimp are two different species of organisms though they belong to crustaceans but have unique orders. The krill has a three-segmented body, while the shrimp only has two.
Both of the organisms vary in body size as krill is smaller in size as compared to shrimp which is comparatively larger and has an elongated body. The lifespan of krill is nearly about 7 years, whereas the shrimp have a lifespan of about 1 to 6 years.
Krill vs Shrimp
The main difference between krill and shrimp is that the krill are of the Euphausiacea order, and the shrimp are the Natantia suborder of the Decapoda order. It has been said that krill only has 85 species, whereas shrimp has more than 1900 species. Krill are smaller in size as compared to shrimp. Moreover, krill are transparent, and shrimp are colorful.
Krill is considered as an important trophic level connection between the food chains. They feed on various planktons and zooplanktons. They are the food source of a majority of fishes and larger animals. In various countries, krill has been used as a food source for human consumption. Krill is also used in the aquaculture industry and as fish food.
Shrimp are abundant in nature. They play a key role in the food chain. The muscular part of the shrimp is used for human consumption. The shrimps are omnivore organisms that are their food source can be plants as well as animals. The larger shrimps are likely to be targeted more for commercial use. Larger shrimps are called prawns, and they have a much larger industry.
Comparison Table Between Krill and Shrimp
| Parameters of Comparison | Krill | Shrimp |
| Order | Euphausiacea | Decapoda |
| Size | Smaller | Comparatively Larger |
| Body Structure | Three segment body- Cephalon, thorax, and abdomen | Two segment body- cephalothorax and abdomen |
| Characteristic | Mostly Transparent | Colorful |
| Reproduction | Lay thousands of eggs per year | Lay millions of eggs per session |
What is Krill?
Krill are small crustaceans of the order Euphausiacea, and it has been reported that 85 different species of krill are found in the world’s ocean. The krill is about 6 cm in length and a gram in weight when they are fully matured. The krill has a longer life span. That is, it can live up to 7 years. The krill are mostly transparent, but their shell is bright red.
The krill is zooplankton that can float at the upper surface of the water and is at the mercy of ocean currents. They are not able to swim in the water because they change their position. At night time, the krill feed on the surface of the water, while during the daytime, it sinks deeper into the water column. It has also been reported that they are found in abundant quantities in the Antarctic ocean. The Antarctic krill can lay up to 8,000 eggs per brood, and the season may last for about 5 months.
In the 19th century, krill was considered a food source for humans and animals. Krill has been a major source of proteins and omega-3 fatty acids and was used as a human food source in the early 21st century as dietary supplements, livestock food, capsules, etc. Also, krill is used in aquaculture and as fish food for the pharmaceutical and healthcare industry.
What is Shrimp?
Shrimp have decoded crustaceans with elongated and two-segmented bodies, i.e., cephalothorax and abdomen. Its body color also varies from species to species and can be influenced by age, harvest season, diets, and the farm sites. But when the shrimps are cooked, their color changes to pink or reddish. Shrimp are widespread and abundant. Shrimps are considered a very important part of the food chain. They are the food sources for larger animals ranging from fish to whales. Shrimp are found in all oceans, freshwater lakes, and streams.
The length varies from a few millimeters to more than 20 cm. The size of shrimp is approximately between 4 to 8 cm. It has thin, fragile legs, which they use primarily for perching. The life span is one to seven years. The shrimp can easily swim backwards by flexing the abdomen and the tail. The primary source of food consists of small plants and animals. The female shrimp can lay 1500 to 14000 eggs that are attached to its swimming legs. Moreover, the swimming larvae can go through the five stages of development before they become juvenile. The larger size of shrimp is called prawns.
The muscular tail of shrimp is used for human consumption. The shrimp are low in fat and are a rich source of protein and omega-3 fatty acids. Not only this, but it has also been caught and used for farming. Currently, the world supply of shrimp has exceeded the demand. Farming the commercial shrimp species has industry support of about 50 billion dollars a year.
Main Differences Between Krill and Shrimp
- Krill has three segments in the body that are cephalon, thorax, and abdomen, whereas the shrimp has only two segments, and that is cephalothorax and abdomen.
- The life span of krill is ten years, whereas the lifespan of shrimp is two years.
- Krill has only a pair of antennae, while shrimp has two pairs of antennae.
- Krill are herbivores. On the other hand, shrimp are omnivores.
- Krill are generally smaller in size, whereas shrimp are comparatively larger.
Conclusion
The krill and shrimp are crustaceans, but they both belong to different orders. The krill are smaller in size as compared to shrill. There have been 85 species of krill, which are known to date, and for shrimp, 1900 species are known. They both play an important role in the food chain and are also the food source for several fishes and larger animals.
The farming of shrimp has benefitted the industry a lot. Whereas the krill is a rich source of proteins and omega -3 fatty acids are used as capsules, dietary supplements, etc. Both species have a lot of benefits, and it has been proven to benefit both animals and humans.
References
- https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-2095.2010.00791.x
- https://books.google.co.in/books?hl=en&lr=&id=yo8fRGvracAC&oi=fnd&pg=PA262&dq=krill+vs+shrimp&ots=9KmjHKdKxo&sig=kdS_iRejiERKly65AjqAqV9UBXY