Subscribe to:
Post Comments (Atom)
skip to main |
skip to sidebar
In summer 2010, an Anglo-Chinese expedition led by Prof. Rudy Gozlan will be going back to remote parts of China to find the origin of a fish invasion. A group of scientists from Bournemouth University and the Chinese Academy of Science will collect topmouth gudgeon material from 33 locations covering 9 major catchments and a trail of 10000km.
A fish on the trail of Genghis Khan
In the world of fish Topmouth gudgeon Pseudorasbora parva, a small cyprinid native to East China, has matched and gone beyond the great Mongol invasion, resulting in the vast range expansion covering much of Asia, Europe and now with a foothold in North Africa. The stealth invasion started in the 1950’s with the end of the Chinese civil war (from around 1840 to 1949) which had restricted human population mobility and trade. At that time, there was an increasing need for developing new sources of animal protein and black carp, grass carp, silver carp and big head carp were rapidly introduced from East China especially from the middle and lower reaches of the Yangtze River basin to many other places including Yunnan, Qinghai, Gansu and Xinjiang. This species had been cultured traditionally in East China for a long time with specific culturing techniques. These carp introductions for aquaculture have been the beachhead of topmouth gudgeon’s great escape.
Small in size (maximum length circa 9cm), highly fecund with batch spawning and nest guarding behaviour and highly tolerant to environmental changes, topmouth gudgeon has all the attributes of a successful invader. Its first introduction outside of China was in reservoirs and ponds around the black sea as part of a fish farming agreement between China and the former Eastern block. Following long distances and hitchhiking cross country with movements of carp, it rapidly escaped and colonised local waters, dominating communities in ponds and lakes. Recently identified as a healthy carrier of a deadly non-species specific eukaryotic parasite Sphaerothecum destruens, it now poses a threat to European fish diversity.
Preserved material will be compared to material collected from populations established from the first introduction in each country within the non-native range. Topmouth gudgeon has been introduced for several decades to countries with clear contrasting climatic conditions such as Poland, Italy and Algeria. This will provide a unique opportunity to study adaptation under contrasting climatic conditions. Populations will be compared for their life history traits and parasitic communities as well as their population genetic structure within native range but also across introduced range. In addition, live topmouth gudgeon will be brought back from China and various parts of the non-native range to characterise the reaction norms of different populations along thermal gradients. Individual fitness, measured as the number of reproductive events, size of batches and larval growth will be measured for several contrasting populations under a range of controlled thermal challenges. This will allow the evolutionary and phenotypic shift that has occurred during topmouth gudgeon invasion to be measured.
Beyond the immediate scientific interest this expedition represents a cultural and historical journey where an innocent movement of fish from the East coast to the West part of China has rippled all the way to England 50 years later.
Small in size (maximum length circa 9cm), highly fecund with batch spawning and nest guarding behaviour and highly tolerant to environmental changes, topmouth gudgeon has all the attributes of a successful invader. Its first introduction outside of China was in reservoirs and ponds around the black sea as part of a fish farming agreement between China and the former Eastern block. Following long distances and hitchhiking cross country with movements of carp, it rapidly escaped and colonised local waters, dominating communities in ponds and lakes. Recently identified as a healthy carrier of a deadly non-species specific eukaryotic parasite Sphaerothecum destruens, it now poses a threat to European fish diversity.
Preserved material will be compared to material collected from populations established from the first introduction in each country within the non-native range. Topmouth gudgeon has been introduced for several decades to countries with clear contrasting climatic conditions such as Poland, Italy and Algeria. This will provide a unique opportunity to study adaptation under contrasting climatic conditions. Populations will be compared for their life history traits and parasitic communities as well as their population genetic structure within native range but also across introduced range. In addition, live topmouth gudgeon will be brought back from China and various parts of the non-native range to characterise the reaction norms of different populations along thermal gradients. Individual fitness, measured as the number of reproductive events, size of batches and larval growth will be measured for several contrasting populations under a range of controlled thermal challenges. This will allow the evolutionary and phenotypic shift that has occurred during topmouth gudgeon invasion to be measured.
Beyond the immediate scientific interest this expedition represents a cultural and historical journey where an innocent movement of fish from the East coast to the West part of China has rippled all the way to England 50 years later.
The TEAM
ALL ALONG THE EXPEDITION I WILL KEEP THE BLOG ALIVE SO GET IN TOUCH, ASK QUESTIONS AND I WILL BE AS REACTIVE AS POSSIBLE TAKING YOU ALONG THE JOURNEY. :-)
Hi guys,
ReplyDeleteI'm back in England now. Good to hear that the trip and also sampling is going well, even without me ;-). Hope Yahui has managed to collect some more Carassius for me?! Although it is great to be back here with my family I envy you. What I don't miss is the 8 hours in the car each day. My back and bottom are glad that this is over. I bet you are also happy to have a bit more space on the back bench?
I had a great time in Beijing. I'm glad that I decided to stay in the town centre - made things much easier. Friday evening I had a wonder to Tiananmen square and beyond (a good place for going out). Met lots of nice people, but also plenty of conmen who try to drag you into a restaurant of "their choice". Saturday I went shopping with my friend Liying, had Peking duck and saw the Summer palace. Plenty of fish in the lake! Rudy, if you go there take a net, maybe you can catch some of Nicols rare TMG morphotypes!!
A word of advice concerning shopping. Most of the alleged silk stuff I bought turned out to be fake. Without having real silk as a comparison it is difficult to tell (for me anyway), although Kerry noticed within a few seconds :-(
In fact the only real silk thing I bought was from the airport shop. My advice, buy your stuff there.
Saw the great wall at Mutianyu on Sunday. As expected it was quite touristy but stunning nevertheless. On the bus I met a couple of crazy Spanish ladies in their 60ies and we went out in the evening – had a great time!
I’m looking forward to the Semifinal with Spain tomorrow. Raffa, fair play, may the better team win! Although I do have to say that so far this was clearly Germany. But then every game is different and Spain has still live up to their potential, maybe they will tomorrow!
Take care and thanks to everybody who has taken an interest in our Blog so far!
Bernd