Psephurus gladius, Chinese Paddlefish

Transcription

1 The IUCN Red List of Threatened Species ISSN (online) IUCN 2008: T18428A Psephurus gladius, Chinese Paddlefish Assessment by: Qiwei, W. View on Citation: Qiwei, W Psephurus gladius. The IUCN Red List of Threatened Species 2010: e.t18428a Copyright: 2015 International Union for Conservation of Nature and Natural Resources Reproduction of this publication for educational or other non-commercial purposes is authorized without prior written permission from the copyright holder provided the source is fully acknowledged. Reproduction of this publication for resale, reposting or other commercial purposes is prohibited without prior written permission from the copyright holder. For further details see Terms of Use. The IUCN Red List of Threatened Species is produced and managed by the IUCN Global Species Programme, the IUCN Species Survival Commission (SSC) and The IUCN Red List Partnership. The IUCN Red List Partners are: BirdLife International; Botanic Gardens Conservation International; Conservation International; Microsoft; NatureServe; Royal Botanic Gardens, Kew; Sapienza University of Rome; Texas A&M University; Wildscreen; and Zoological Society of London. If you see any errors or have any questions or suggestions on what is shown in this document, please provide us with feedback so that we can correct or extend the information provided. THE IUCN RED LIST OF THREATENED SPECIES

2 Taxonomy Kingdom Phylum Class Order Family Animalia Chordata Actinopterygii Acipenseriformes Polyodontidae Taxon Name: Psephurus gladius (Martens, 1862) Common Name(s): English: Chinese Paddlefish Assessment Information Red List Category & Criteria: Critically Endangered (Possibly Extinct) A2cd; C2a(i); D ver 3.1 Year Published: 2010 Date Assessed: October 24, 2009 Justification: The population of the Chinese Paddlefish decreased due to historical overfishing and habitat degradation. In 1981, the construction of the Gezhouba Dam in the middle reaches of the Yangtze River blocked the migration route of this species, preventing adult fish moving to the upper reaches of the river to spawn. Only two adult specimens (both females) have been recorded since 2002, despite recent surveys to re-discover the species. Juveniles were last recorded in the lower reaches of the river in It is expected that there are less than 50 mature individuals left in the wild and this species is assessed as Critically Endangered (Possibly Extinct), though more extensive surveys are needed in areas across the species range in order to confirm whether or not individuals of this species remain. Date last seen: 2003 Previously Published Red List Assessments 1996 Critically Endangered (CR) 1994 Vulnerable (V) 1990 Vulnerable (V) Geographic Range Range Description: The Chinese Paddlefish is endemic to the Yangtze River (including the brackish water of the mouth) in China. Country Occurrence: Possibly extinct: China 1

3 Population From the mid-20th century the population of the Chinese Paddlefish decreased significantly. Incidental capture data between from the upper, mid and lower sections of the Yangtze River indicate the largest number of this species found during this period was in 1985, when 32 individuals were captured in the lower section (below the Gezhouba Dam) (Zhang et al. 2009). In 1995 juveniles of this species were recorded below the Gezhouba Dam of the Yangtze River (Chen 2008). Two specimens (1.2 kg weight, 47 cm tail length; 1.3 kg weight, 50 cm tail length) were found in the Chongqing reach in 1992 (Chen 2007). In 2002, a female Chinese Paddlefish (body length 330 cm, weight 117 kg) was captured in the section of Jiangsu Nanjing, Yangtze River. Urgent attempts were made to save this individual, but it only survived in captivity for 30 days. On Jan 24th, 2003, a female (body length 352 cm) was accidentally caught in Yibin, Sichuan Province China (upper stream of Yangtze River). It was captured, tagged with an ultra-sonic tag and released by Dr. Wei s team of the Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences. Unfortunately, after 12 hours of tracking, communication was disconnected. Between 2006 and 2008, Dr.Wei s team used a number of boats to deploy 4,762 setlines, 111 anchored setlines and 950 drift nets covering a stretch of km of the upper Yangtze River in a bid to catch the fish, but they failed to catch a single individual (Zhang et al. 2009). The team also used hydroacoustic equipment that beams sound through the water to create a picture of the river and anything in it. This identified nine possible targets, of which two could be paddlefish (Zhang et al. 2009). This species is considered to be the verge of extinction. Artificial reproduction has not been successful. Current Population Trend: Unknown Habitat and Ecology (see Appendix for additional information) This paddlefish is considered anadromous (spends at least part of its life in the sea and migrates upriver to reproduce). This species occurs in broad surfaced main streams of large rivers, staying usually in middle and lower layers of the water column, and occasionally swims into large lakes. Its spawning period is in March and April. Spawning sites are located in the upper reaches of the Changjiang River. Available information also indicates that spawning took place in the lower Jinsha River between Shuifu and Yibin (Liu and Zeng 1988, Li et al. 1997). The largest specimen recorded was 7 m in length and weighed over several thousand pounds. Systems: Freshwater, Marine Use and Trade (see Appendix for additional information) This species has historically been overfished for human consumption. Threats (see Appendix for additional information) The Chinese Paddlefish has historically been overfished. The long-life history of this species (e.g. late sexual maturation and large size) means the population will take a longer time to recover from depletion. 2

4 In 1981 the Gezhouba Dam was built in the middle reaches of the Yangtze River, blocking the migration route of this species and preventing adult fish moving to the upper reaches of the river to spawn. Fries of P. gladius form schools along the river, thus becoming easily captured in traditional Chinese fishing nets and set nets (Zhang et al. 2009). Conservation Actions (see Appendix for additional information) P. gladius is listed as a first-class state protected animal in China. Due to its endemicity and rarity, this species possesses significant academic and economic importance. This species was listed on CITES Appendix II in An integrated rescue programme was initiated in This extensive programme hopes to re-discover this species. It is also investigating habitat and plans to conduct studies on foraging behaviours and instigate captive breeding programmes, propagation for release, preservation of genetic resources, and even cloning (Zhang et al. 2009). The Protective Laws of Aquatic Products Resources should be implemented and increased awareness of the significance of the protection of the species is needed (Wei Qiwei et al. 2003). Current studies hope to investigate artificial breeding with the hope of releasing captive bred fries into rivers, ponds and reservoirs. The success of this work depends upon finding wild adult specimens. Credits Assessor(s): Qiwei, W. Reviewer(s): Pourkazemi, M., Zhang, H., Du, H. & Smith, K. 3

5 Bibliography Anonymous The biology of sturgeons and paddlefish in the Yangtze and their artificial propagation [in Chinese]. Sichuan Scientific and Technical Publishing House, Chengdu, China. Chen, X.H Biology and resource situation of Acipenseriformes [in Chinese]. pp Ocean Press, Beijing. Fan, X.G., Wei, Q.W., Chang, J., Rosenthal, H., He, J.X., Chen, D.Q., Shen, L., Du, H. and Yang, D.G A review on conservation issues in the upper Yangtze River a last chance for a big challenge: Can Chinese paddlefish (Psephurus gladius), Dabry's sturgeon, (Acipenser dabryanus) and other fish species still be saved? Journal of Applied Ichthyology 22(suppl 1): Fu, C., Wu, J., Chen, J., Wu, Q. and Lei, G Freshwater fish biodiversity in the Yangtze River basin of China: patterns, threats and conservation. Biodiversity and Conservation 12: IUCN IUCN Red List of Threatened Species (ver ). Available at: (Accessed: 10 March 2010). Mims, S.D Aquaculture of paddlefish in the United States. Aquatic Living Resources 14: Yun, L., Xiaoming, D. and Jianhu, J A preliminary study on the morphology, growth of juvenile Psephurus gladius on the upper reaches of the Changjiang River and a survey of its spawning grounds. Journal of Southwest Agriculture University 5: Zhang, H., Wei, Q., Du, H., Shen, L. Li, Y. and Zhao, Y Is there evidence that the Chinese paddlefish (Psephurus gladius) still survives in the upper Yangtze River? Concerns inferred from hydroacoustic and capture surveys, Journal of Applied Ichthyology 25(Suppl 2): Zhong, Y., Bin, Z. and Jianbo, C DNA extraction formalin-fixed tissue of Psephurus gladius and the applicability of microsatellite primers developed from its related species. Journal of Lake Sciences 20(2): Citation Qiwei, W Psephurus gladius. The IUCN Red List of Threatened Species 2010: e.t18428a Disclaimer To make use of this information, please check the Terms of Use. External Resources For Images and External Links to Additional Information, please see the Red List website. 4

6 Appendix Habitats ( Habitat Season Suitability Major Importance? 5. Wetlands (inland) -> 5.1. Wetlands (inland) - Permanent Rivers/Streams/Creeks (includes waterfalls) 5. Wetlands (inland) -> 5.5. Wetlands (inland) - Permanent Freshwater Lakes (over 8ha) - Suitable Yes - Suitable No 9. Marine Neritic -> Marine Neritic - Estuaries - Suitable - Use and Trade ( End Use Local National International Food - human No Yes No Threats ( Threat Timing Scope Severity Impact Score 4. Transportation & service corridors -> 4.3. Shipping lanes 5. Biological resource use -> 5.4. Fishing & harvesting aquatic resources -> Intentional use: (subsistence/small scale) 5. Biological resource use -> 5.4. Fishing & harvesting aquatic resources -> Intentional use: (large scale) 5. Biological resource use -> 5.4. Fishing & harvesting aquatic resources -> Unintentional effects: (subsistence/small scale) 5. Biological resource use -> 5.4. Fishing & harvesting aquatic resources -> Unintentional effects: (large scale) Past, unlikely to return Past, unlikely to return

7 7. Natural system modifications -> 7.2. Dams & water management/use -> Dams (size unknown) 1. Ecosystem stresses -> 1.1. Ecosystem conversion 2. Species Stresses -> 2.3. Indirect species effects -> Other 8. Invasive & other problematic species & genes -> 8.1. Invasive non-native/alien species -> Unspecified species 2. Species Stresses -> 2.3. Indirect species effects -> Hybridisation 9. Pollution -> 9.1. Domestic & urban waste water -> Sewage 1. Ecosystem stresses -> 1.2. Ecosystem degradation 9. Pollution -> 9.2. Industrial & military effluents -> Oil spills 1. Ecosystem stresses -> 1.2. Ecosystem degradation 9. Pollution -> 9.3. Agricultural & forestry effluents -> Soil erosion, sedimentation 1. Ecosystem stresses -> 1.2. Ecosystem degradation 9. Pollution -> 9.4. Garbage & solid waste 1. Ecosystem stresses -> 1.2. Ecosystem degradation 11. Climate change & severe weather -> Temperature extremes 2. Species Stresses -> 2.2. Species disturbance 2. Species Stresses -> 2.3. Indirect species effects -> Other Conservation Actions in Place ( Conservation Actions in Place In-Place Research, Monitoring and Planning Action Recovery plan: Yes Systematic monitoring scheme: Yes In-Place Species Management Subject to ex-situ conservation: Yes In-Place Education Included in international legislation: Yes Subject to any international management/trade controls: Yes Conservation Actions Needed 6

8 ( Conservation Actions Needed 1. Land/water protection -> 1.1. Site/area protection 1. Land/water protection -> 1.2. Resource & habitat protection 2. Land/water management -> 2.1. Site/area management 2. Land/water management -> 2.3. Habitat & natural process restoration 3. Species management -> 3.1. Species management -> Harvest management 3. Species management -> 3.1. Species management -> Trade management 3. Species management -> 3.2. Species recovery 3. Species management -> 3.4. Ex-situ conservation -> Captive breeding/artificial propagation 3. Species management -> 3.4. Ex-situ conservation -> Genome resource bank 4. Education & awareness -> 4.1. Formal education 4. Education & awareness -> 4.2. Training 4. Education & awareness -> 4.3. Awareness & communications 5. Law & policy -> 5.1. Legislation -> National level 5. Law & policy -> 5.2. Policies and regulations Research Needed ( Research Needed 1. Research -> 1.2. Population size, distribution & trends 1. Research -> 1.3. Life history & ecology 1. Research -> 1.5. Threats 1. Research -> 1.6. Actions 2. Conservation Planning -> 2.1. Species Action/Recovery Plan 2. Conservation Planning -> 2.2. Area-based Management Plan 2. Conservation Planning -> 2.3. Harvest & Trade Management Plan 3. Monitoring -> 3.1. Population trends Additional Data Fields Population Number of mature individuals:

9 Habitats and Ecology Generation Length (years): Movement patterns: Full Migrant 8

10 The IUCN Red List Partnership The IUCN Red List of Threatened Species is produced and managed by the IUCN Global Species Programme, the IUCN Species Survival Commission (SSC) and The IUCN Red List Partnership. The IUCN Red List Partners are: BirdLife International; Botanic Gardens Conservation International; Conservation International; Microsoft; NatureServe; Royal Botanic Gardens, Kew; Sapienza University of Rome; Texas A&M University; Wildscreen; and Zoological Society of London. THE IUCN RED LIST OF THREATENED SPECIES