As reported earlier, an ill-fated eel somehow ended up in the butt of an allegedly constipated Chinese gentleman. Two European fish experts have now taken a closer look at a photograph of the eel in question and given their expert opinion on its identity.

When discussing the fish-in-butt incident with Swedish ichthyologist Dr Sven Kullander, Dr Ralf Britz of London’s Natural History Museum – an expert on the order Synbranchiformes – suggested that this fish might not be an eel at all. Instead, he believes the elongated fish to be a member of the species Monopterus albus, since the tip of its tail is very slender and the gular region somewhat inflated.

Despite not being a true eel, Monopterus albus is commonly known as Asian swamp eel in English. It is a popular food fish in parts of south-east Asia and you can buy it alive in fish markets. All young swamp eels are female but some of the change sex and become male as they age. If a male swamp eel founds itself in an environment with no or very few females, he can change himself back into a female fish again. The change from one sex to the other can take up to a year.

If you ever feel the need to insert a swamp eel into your body, we here at AC Tropical Fish suggest you do it orally.

Swamp Eel Chowder
4 servings

Ingredients
Ruhgly 600 g Monopterus albus
150 g Lean Pork
50 g Dry Black Fungus
5 pieces of Dry Black Mushroom
3 tbsp cooking oil
1 tbsp Shaoxing Wine
1 L Chicken Stock
2 tbsp Shredded Lemon Leaves
1 tbsp Shredded Ginger
1 tbsp Chopped Parsley

Ingredients for seasoning
3 tbsp Water Chestnut Powder
1 tbsp Water
1 tbsp Sesame Oil
1/2 tbsp Dark Soy Sauce
1/2 tbsp Light Soy Sauce
1/2 tbsp Salt
1 tsp pepper

Instructions
1.) Prepare the seasoning by stirring all seasoning ingredients together. Set aside.
2.) Remove the bones from the eel.
3.) Wash the eel meat in hot water and shred it.
4.) Let the black fungus and black mushrooms soak in water until they become soft.
5.) Shred the black fungus and black mushrooms.
6.) Clean the pork and shred it.
7.) Heat up a wok or large frying pan and add the cooking oil.
8.) Add the eel meat to the wok and stir fry.
9.) Add wine and chicken stock and bring to a boil.
10.) Add the shredded fungus, mushrooms, and pork and cook for 5 minutes while stirring.
11.) Add ginger and parsley and cook at low heat for another 5 minutes while stirring.
12.) Add the seasoning, continue to cook and stir for 2 more minutes.
13.) Sprinkle with chopped parsley before serving.

* If you want to see the low resolution picture of the actual specimen extracted at the Kwong Wah Hospital, the paper where it is included has been published in the journal Surgery. “Siu Fai Lo, Sin Hang Wong, Lok Sang Leung, In Chak Law, Andrew Wai Chun Yip, Traumatic rectal perforation by an eel, Surgery, Volume 135, Issue 1, January 2004, Pages 110-111”.

In May this year, hundreds of Asian swamp eels were discovered in and around Silver Lake in historic Gibbsboro, New Jersey. This was the first finding in New Jersey, Asian swamp eelbut not the first finding in the United States. Unlike Florida, Georgia, and Hawaii – the three other U.S. states where this species have been discovered – New Jersey is however subjected to harsh winters and a breeding population of Asian swamp eels in New Jersey confirms the suspicion that this Asian invader has no problem adjusting to the
chilly climate of northern North America.

The Asian swamp eels were found by a local college student checking on frogs and turtles in the Silver Lake. As he spotted snake-like heads peeking from the water, he decided to photograph them and post the pictures online. This lead to the “snakes” being identified as Asian swamp eels, Monopterus albus, and prompted a call to the local authorities.

In its native environment in Asia and Australia, the swamp eel Monopterus albus inhabits gentle hill streams, estuaries and lowland wetlands, and it is a common species in rice paddies. It has developed a long row of traits that makes it an apt survivor in many different kinds of environments. Unfortunately, these traits also make it the “perfect” invasive species and biologists fear that the Asian swamp eel may wreck havoc with existing North American ecosystems, especially if the predatory species of these systems prefer to target familiar prey rather than catching the newcomers.

– The Asian swamp eel can survive long periods of drought by burrowing in moist earth, and can therefore take advantage of seasonally appearing, short-lived bodies of water.

– If its home becomes unsuitable, e.g. because of drought, this eel simply crawls ashore and make its way to a more suitable home by slithering over land, just like a snake. This makes it hard to eradicate from bodies of water using poison or similar; there is always the risk of at least two specimens getting away over land and forming a new breeding colony in nearby waters.

– The Asian swamp eel can tolerate a wide range of oxygen levels in the water since it is capable of absorbing oxygen from the air above the surface through its skin. This skill doesn’t only come in handy in oxygen depleted waters; it is also what makes it possible for the fish to travel impressive distances over land.

– This eel prefers freshwater habitats, but can tolerate brackish and saline conditions, which increases its chances of always finding a suitable home.

– It eats all sorts of prey, not only fish, crustaceans, amphibians, and other aquatic animals, but detritus (decaying organic matter) as well. Highly specialized feeders have a much harder time adjusting to new habitats and are therefore less likely to become problematic invasive species.

– This eel is a protandrous hermaphrodite, which means that it can change its sex. All specimens are born male, but can turn into females if necessary. This means that if an aquarist releases two male specimens into a lake, one of them can turn into a female to make reproduction possible.

In Georgia, the first specimens of Asian swamp eel was discovered in 1994, and three years later eels were found in Florida as well. The Hawaiian history of combating swamp eels is much longer as the first specimens are believed to have been released in Hawaiian waters about 100 years ago. In Georgia and New Jersey, biologists blame aquarists of having caused the situation by releasing their pets into the wild. In Florida and Hawaii however, Asian food markets and fish-farmers are considered more likely sources. Asian swamp eels are typically sold fresh in food markets and can be kept alive for long periods of time as long as their skin is kept moist.

New Jersey authorities are now focusing on containing the creatures while trying to figure out a way of annihilating them. “We’re not panicking yet,” says Lisa Barno, chief of the New Jersey Bureau of Freshwater Fisheries. “It’s more that it’s just an invasive species we’d rather not have. We’re still documenting the true extent of the problem, but right now it seems to be fairly contained.” One of the immediate goals is to prevent an expansion downstream to the Cooper River and a watershed leading to the Delaware River. Since May, only one Asian swamp eel has been discovered outside the Silver Lake.