Is Red Nile Tilapia an Invasive Species?
By: Raul Pajaro Sanchez
Tilapia is typically an herbivorous species, however, the Red Nile Tilapia (Oreochromis niloticus) is an omnivorous type of fish that feeds on plants and animals, including eggs and larvae. The accidental and deliberate introduction of tilapia species into any ecosystem can lead to a plague with irreparable damage to the environment and the economy of the region where it occurs. According to experts, tilapia’s ability to adapt and reproduce quickly allows it to dominate most of the environments where it is introduced - this makes it an invasive species. Studies indicate that invasive species, including tilapia, have a negative impact on the global economy of approximately $1.4 billion US dollars annually.
The problem with tilapia occurs when it is released into ecosystems where endemic species are not prepared to coexist or fight to survive. The Red Nile Tilapia adapts and reproduces quickly, so controlling them or expelling them from a free habitat is complicated, time-consuming, and expensive. The impact of any introduction varies according to the geographical region and the specific ecosystem. Generally, given its resistance, voracity, and high growth rate, tilapia easily becomes a competitor to other fish species.
Tilapia are responsible for severe ecological impacts in natural environments, such as the displacement of native species in the river to other bodies of water like seas and oceans. Likewise, as an exotic species, it is invasive in developing countries. Additionally, their treatment has also been changing them over the last 20 years. In the catalog of exotic and transplanted aquatic biodiversity in Colombia, Oreochromis niloticus is considered a high-risk species, giving it a score of 1056 out of a maximum value of 1500 points (Gutiérrez et al., 2010 cited by Gutiérrez & Lasso, 2012).
In addition, Australia has indicated that the Red Nile Tilapia is an extreme risk in the risk analysis of introduced exotic fish species, giving it a rating of 23 (out of 24) points (Bomford & Glover, 2004). Other countries that have also reported the Red Nile Tilapia as an invasive species are Bangladesh, Japan, Peru, the Philippines, India, Taiwan, Thailand, Japan, and the United States (Global Invasive Species Database, 2012c).
Red Tilapia and Specifications
Within the Genus Oreochromis, the first ancestor of red Tilapia is reported as an “albino mutation” in a traditional culture of tilapia Oreochromis mossambicus with a standard color (black) introduced from Singapore in 1946, near the town of Tainan (Taiwan) in 1968.
Ho Kuo (Taiwan Fisheries Research Institute) in 1969 made the cross between the reddish-orange mutant male O. mossambicus and the normal-colored female O. niloticus, obtaining an F1 with 25% of reddish-orange fingerlings. After nine years, selective crosses could fix the red coloration in 70 to 80% of the population.
The Red Tilapia became the spearhead for the accelerated development of commercial fish farming from the 1980s on in countries with no South American aquaculture tradition, such as Colombia (introduced in 1982), Venezuela (introduced in 1989), and Ecuador (introduced in 1993) almost simultaneously with Central American, the Caribbean and North American countries.
The development of this hybrid allowed the market to obtain many advantages over other species.
- A high percentage of muscle mass (Large steak)
- Absence of intramuscular spines
- Rapid growth
- Adaptability to the environment
- Disease resistance
- Excellent texture and color of meat, with outstanding acceptance in the market