Not just ugly
Lina Mahmoud investigates mixed opinions on the transplanted freshwater crayfish in Cairo's Nile waters
"I have been selling it for months. I eat it too. It's delicious," said Nawal Mohamed, who peddles freshwater crayfish at Imbaba's fish market. She conceded that five years ago people were scared to buy crayfish, but optimistically claimed that these days they have grown accustomed to the originally North American shellfish. In front of her is a basket of her wares: dark-shelled ominous- looking mini-lobster-like creatures wiggling their tentacles and tails at potential buyers. Hind El-Sayed, a housewife who lives in Giza, shuddered at Nawal's goods and said she was "too scared to buy it".
The crayfish Procambarus Clarkii was accidentally introduced to the Nile during the 1980s. "The owner of a fish farm imported it from the United States thinking it was a kind of prawn. But the crayfish eventually ate themselves through the mud partitions of his farm and spoiled his other tanks," explained Magdi Tawfik, professor of zoology at Ain Shams University. "So he decided to get rid of the destructive fish by letting them off into in the Nile."
The Ain Shams University Department of Zoology has been studying this species of crayfish for 10 years in collaboration with the University of Texas and the Louisiana-based Institute for Fresh Water Crayfish Studies. P Clarkii is native to the south-central United States and northeastern Mexico.
"However, the Egyptian environment is ideal for its growth because of the warm weather, the organic material available in our waters and the Nile River's abundance in shells and plants," Tawfik said.
This particular shellfish is distinguished by its high fertility. Each one lays 200 eggs at least three times a year. Its proliferation in the Nile has thus been rapid, especially given that the waterway is free of credible competitors.
Many fishermen and vendors still believe P Clarkii is an insect, and consider the crayfish to be dangerous and even poisonous. "We call them the sea cockroaches. They are a danger to the fish population of the Nile. In short, they are very bad," said Sayed, a fishermen selling his catch at the Giza fish market.
Rafik Mohamed, a computer science student and fishing enthusiast, casting from the Munib bridge in Giza also believes that the crayfish is a poisonous insect -- and has the empirical know- how to back up his claim. "I used to put them in a glass of water and watch them for a while," he said. "But it's very boring."
However, Tawfik believes that after a decade of study and research the P Clarkii can be deemed a pollution-free source of seafood protein. Research has proven that despite being fond of all types of meat, crayfish do not harm the species of fish that live in the Nile. They're scavengers, a trait scientists say could be useful in ridding the Nile bed of dead snails that pollute Egyptian waters. Tawfik explained that while the crayfish "clean the Nile water from harmful pollutants, its shell is shed five to six times a year, ridding the crayfish of harmful pollutants. Hence the poisonous material absorbed into the shell does not affect the meat of the crayfish."
Some fishermen accuse P Clarkii of tearing their fishing nets and even eating their catch. Others complain that fish are no longer as abundant since the crayfish was introduced into the Nile.
"Every day I find torn fish in my net. These have been ravaged by the crayfish and I end up eating the remains of the fish with my family," said Mohamed Hassan, a fisherman in Manial.
Tawfik revealed that P Clarkii is in fact very slow and has weak eyesight, so while it cannot catch fish swimming freely in the water, it can get at those in a net.
The solution? Eat crayfish in huge quantities, said Tawfik.
