Archives for July 23, 2006

The Yangtze River Dolphin, also known as the baiji, is perhaps the most endangered of the world’s large mammals. The last confirmed sighting was of a single adult in September 2004.

The journal Conservation Biology recently published three short papers [1] on the current state of baiji conservation and plans to save the species.

There is no single agreed plan, rather several disputed and contentious plans which can perhaps be summarized as four options:
1. Leave the baiji where they are.
2. Move individuals to the Institute of Hydrobiology dolphinarium in Wuhan, Hubei Province.
3. Move individuals to a 21-km oxbow lake originally part of the Yantze River at Tian-e-Zhou, Hubei Province.
4. Move individuals somewhere else.

The first option has been advocated by Professor Guang Yang and colleagues [1] on the basis that the chances of successfully finding, capturing and establishing a genetically viable ex situ population of baiji is unlikely. They argue that the baiji is essentially a lost cause, that available resources should be prioritized, and would be better spent on saving the finless porpoise population of the Yangtze river.

Drs Randall Rheeves and Nick Gales [1] reject the notion of leaving the baiji in situ. They claim that the baiji will surely go extinct if left in the Yangtze because of harmful fishing practices as well as increasingly river traffic, water pollution and habitat loss. They claim that it is more important to save the baiji than the finless porpoise. They explain that finless porpoises can be found from Japan to Iran in a narrow band of coastal continental shelf water while the baiji are only found in the Yangtze and “their disappearance would be like snapping off a complete branch from the tree of mammalian radiation.” They claim it should not come down to a choice between finless porpoises and baiji, that both can be saved.

There seems general agreement that moving baiji to the dolphinarium at Wuhan (Option 2) is not a good idea because previous attempts to establish a breeding colony there have failed.

Guang Yang et al. argue that moving baiji to the Tian-e-Zhou seminatural reserve (Option 3) is not a good idea because it “potentially compromises not only the future of the currently increasing finless porpoise population but would represent a major risk to the baiji due to potential for agonistic interactions, disease transmission, and competition for limited resources.”

A single baiji female released there in 1995 died of entanglement (presumably in fishing nets) but was already emaciated.

In contrast Drs Reeves and Gales argue that moving baiji to the Tian-e-Zhou reserve is the best option because finless porpoises have similar requirements to the baiji and the reserve has proven success for breeding the porpoises.

Drs Reeves and Gales propose that the population of finless porpoises now in the reserve be moved elsewhere, so there is no potential for competition with the baiji.

But, what about moving the baiji elsewhere – finding another seminatural reserve (Option 4)?

I’m inclined to think that if the finless porpoise population is doing well in the Tian-e-Zhou reserve, leave it alone. Find somewhere else for the baiji and begin preparing this new environment in anticipation of finding enough individuals to capture for translocation.

If enough baiji are never found for translocation, if the species does go extinct, then the new reserve could be used for the hopefully expanding finless porpoise population.

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[1] Thanks to Libby for sending me the papers:

* Guang Yang et al. 2006 ‘Conservation Options for the Baiji: Time for Realism?’ Conservation Biology Volume 20, Number 3, pgs 620-622

* Randall Reeves & Nicholas Gales. 2006 ‘Realities of Baiji Conservation’ Conservation Biology Volume 20, Number 3, pgs 626-628

* Ding Wang et al. 2006 ‘Conservation of the Baiji: No Simple Solution’ Conservation Biology Volume 20, Numbers 3, pgs 623-625

I’ve previously posted ‘Worrying About the Baiji’ .