The Eerie Sadness of China’s Paddlefish

China is home to a fish so rare that photographs of living specimens can be counted on two hands. Its lineage is so bizarre that it has only one close relative, found a continent away, and its skeleton straddles the anatomical cues that divide cartilaginous and bony fish. Even within its kin group, its habits and anatomy are unique.

The Chinese paddlefish or báixún, Psephurus gladius, is the only apparent preferential piscivore in the order Acipenseriformes. (The North American paddlefish is a planktivore, and sturgeons prefer shellfish.) Unlike its American sibling, its “paddle” is conical, and it is sometimes termed the “Chinese swordfish,” “white sturgeon,” or “elephant fish.” As an active, predatory schooling fish, it was once known for leaping across the surface of the Yangtze in large numbers. Rumor holds it can exceed seven meters in length and therefore rivals the beluga sturgeon for status as the largest freshwater or anadromous fish on our planet. However, the largest recorded specimen did not exceed a still-impressive four meters. Chances are, no Chinese paddlefish ever will.

CN veterinary imagery

The báixún was found only in the Yangtze River, and has not been abundant since 1976. Since then, dams on the Yangtze have prevented the free movement of Chinese paddlefish along the river’s length. Boat traffic has increased along the economically critical river, and with it deadly collisions with boat propellers. Pollution, development, and the dams have severed the paddlefish from most of its breeding grounds even as fishing for food continued. This unusual fish received legal protection from the Chinese government on par with what the giant panda and baiji dolphin receive, including severe penalties for harming one, but these were likely too little, too late. Most of the harm has already been done, by pollution, overfishing, and hydroelectricity.

The most recent sightings were in 2002, 2003, and 2007, each of individual specimens that died shortly thereafter. None have followed in the ten years since. The last sighting of juvenile specimens was in 1995. There are dozens of scientific papers that mention the Chinese paddlefish, most of which are anatomical, genetic, and taxonomic studies, or conservation papers pointing out how little is known about Psephurus’s ecology. The báixún’s strange place on the phylogenetic tree is established, but its ecology was still a mystery when its population crashed.

In 2002, a 3.3-meter, 130-kg Chinese paddlefish was caught as bycatch in Nanjing in Jiangsu province. The fishermen carefully towed the injured fish to shore, whereupon sturgeon specialists from Wuhan cut it from the net, sutured its injuries, and rushed it to the Kunshan sturgeon breeding facility in a specialized “fish ambulance.” Dr. Qiwei Wei and his team from the Yangtze River Fisheries Research Institute sustained the báixún with manual feeding for 30 days, but it did not survive. This paddlefish was the first adult to be discovered in 20 years, and the species became a focus of Dr. Wei’s efforts thereafter. Correspondingly, this specific báixún is the most extensively documented individual of its kind, with at nearly a dozen photos of various stages of its rescue in Chinese media.

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Fish ambulance.

A Chinese scientist handles Psephurus in an enclosure.
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In 2003, a 3.5-meter specimen was encountered in a reservoir in Sichuan province. Dr. Wei’s team fitted her with an ultrasonic tag and released, but the tag’s signal persisted for only several days.

The 2003 Sichuan paddlefish being attended to by researchers.
https://www.internationalrivers.org/campaigns/xiaonanhai-dam

In 2004, the last captive adults died without yielding a successful captive breeding program.

Top view of a Chinese paddlefish in a pond.
http://dotearth.blogs.nytimes.com/2009/09/30/another-long-goodbye-chinese-paddlefish/

In 2007, fishermen in Jiayu county in Hubei  province caught a 3.6-meter, 250 kilogram báixún, illegally bringing the fish to shore after being alerted of its protected status and then fleeing. Villagers alerted the authorities, who connected with the Yangtze River institute. Dr. Wei’s team was unable to save the paddlefish, which had sustained injuries during capture and which bore six fishhooks in its mouth. Some accounts claim that Zeb Hogan, host of Monster Fish, was part of the rehabilitation team (having been in the area for his episode on the Chinese sturgeon), but the lack of corroborating sources and lack of footage of the attempted rescue in said episode suggests this may be an error.

The 2007 paddlefish being attended to by researchers. Its tail is visibly wounded.
http://www.china.org.cn/english/environment/196795.htm

From 2006 to 2008, Dr. Wei’s team deployed an enormous quantity of boat-based setlines, anchored setlines, and driftnets to comb over 400 kilometers of the Yangtze River for paddlefish. Although a number of putative sightings were made by sonar, Dr. Wei’s team did not catch a single paddlefish.

In 2012, the Chinese government issued an official postcard and postage stamp commemorating the báixún, based on a photograph of a large specimen dragged to shore by fishermen. After dubbing this animal the “giant panda of the rivers,” with all the symbolic significance to the country’s image that such a name implies, it had little choice but to remind the Chinese people of its splendor. But with ten years since the last adult specimen was found—dead—and twenty since the last encounter with juveniles, after an exhaustive multi-year search found none, the báixún is unlikely to reappear.

Postcard showing a crowd of people standing in ankle-deep brown water with a three-meter-long gray fish.
https://viuspace.viu.ca/handle/10613/371?show=full

Like the thylacine and the baiji before it, the Chinese paddlefish is a ghost now. The hasty photos of harried reporters and pickled specimens in ichthyology labs are its final echo, sad and eerie next to fossils of its ancestors and the thousands of North American paddlefish raised for caviar in Chinese farms. The báixún will not receive the regal majesty of the public aquarium exhibits that currently show Atlantic sturgeon to the world, nor will they ever again delight and awe the world with leaping schools across the Yangtze surface. After millions of years, the Chinese paddlefish has seen its last day. The photo of the listless, bleeding 2007 specimen is the last glimpse that any human will have of this ancient and bizarre creature.

May the báixún be the last such wonder that our world must do without.

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The Eerie Sadness of China’s Paddlefish
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