Acipenser transmontanus (Upper Columbia River subpopulation), White Sturgeon

Transcription

1 The IUCN Red List of Threatened Species ISSN (online) IUCN 2008: T44562A Acipenser transmontanus (Upper Columbia River subpopulation), White Sturgeon Assessment by: Hammond, J. & Spence, C. (Ministry of Water, Land & Air Protection, Canada) View on Citation: Hammond, J. & Spence, C. (Ministry of Water, Land & Air Protection, Canada). Acipenser transmontanus (Upper Columbia River subpopulation). The IUCN Red List of Threatened Species 2004: e.t44562a 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 Acipenseridae Taxon Name: Acipenser transmontanus (Upper Columbia River subpopulation) Richardson, 1836 Parent Species: See Acipenser transmontanus Common Name(s): English: White Sturgeon Assessment Information Red List Category & Criteria: Critically Endangered A3b; E ver 3.1 Year Published: 2004 Date Assessed: April 30, 2004 Annotations: Needs Updating Justification: Upper Columbia white sturgeon were isolated from lower Columbia River stocks in the United States in 1941 following the construction of Grand Coulee Dam and related formation of Lake Roosevelt. Kettle Falls in Washington State is thought to have formed a seasonal barrier to white sturgeon migration prior to its inundation by Lake Roosevelt. Construction of Keenleyside, Mica, and Revelstoke dams on the mainstem Columbia River, Brilliant Dam on the lower Kootenay River, and Waneta Dam on the lower Pend d'oreille River further fragmented the population and altered the natural river regime. In addition, the impoundments created by these dams flooded the riverine system, altering or eliminating critical sturgeon habitats, changing water quality and generally reducing system productivity. Dam construction effects were exacerbated by additional impacts such as pollution and waterfront developments. Despite the regularity of spawning events, age structure analyses show that recruitment began to decline in 1969, and has failed entirely since 1985 (RL&L 1995). Without intervention, white sturgeon in the upper Columbia River will follow a continuing decline and be driven to extinction within three generations. This is based on a generation time of years, fish under the age of 20 are virtually absent from subpopulation, and the maximum age of individuals is in the order of 70 years. Based on these parameters, and continuing decline assuming that recruitment failure continues indefinitely, the last individuals in the subpopulation can be expected to reach extinction in about 50 years. Functional extinction will be reached much sooner. Geographic Range Range Description: Upper Columbia River white sturgeon subpopulation inhabits the Columbia River mainstem upstream 1

3 from Grand Coulee Dam. In this area, the largest documented group of the species resides in the area between Hugh Keenleyside Dam and the Canada U.S. border. Other remnant subpopulations occur, or are suspected, throughout the remainder of the drainage. Radio telemetry has shown that white sturgeon occurring downstream from Keenleyside Dam in Canada are typically either sedentary or localized in their patterns of movement. However, some fish have moved downstream into Lake Roosevelt in Washington State, at least as far downstream as Kettle Falls (RL&L 1995). Similarly, fish tagged in Lake Roosevelt have been recaptured upstream during sampling operations in Canada (BC Ministry of Water, Land and Air Protection, data on file). This evidence of trans-boundary migration suggests that white sturgeon from Keenleyside Dam in Canada to Lake Roosevelt in the U.S. form the same subpopulation. Given the exchange of upper Columbia River white sturgeon across the Canada U.S. border, evidence supporting the concept of a distinct white sturgeon subpopulation in the upper Columbia River can be derived from Anders et al. (2000, in prep). White sturgeon mtdna haplotypes were compared among 13 localities, and six large river systems over the range of the species (Columbia, Snake, Kootenai, Fraser, Nechako, Sacramento rivers) using pairwise frequency-distribution comparisons (Monte-Carlo simulations using 10,000 iterations of exact, weighted, Pearson chi-square tests). Haplotype frequency distributions were significantly different, or nearly so (P=0.09, 0.06, 0.06 and < 0.01), in four cases where Lake Roosevelt white sturgeon were compared with other subpopulations in the Columbia River downstream. These data point to low levels of gene flow between the groups, suggesting the upper Columbia subpopulation could be managed separately. Country Occurrence: Native: Canada (British Columbia); United States (Washington) 2

4 Population The abundance of white sturgeon from the Columbia River mainstem between Keenleyside Dam and the Canada-U.S. border was most recently assessed in 1995, when a population of 1,120 individuals (95% CI = 980 to 1,300) was estimated (RL&L 1996a). This figure does not include sampling in Lake Roosevelt in Washington State, and thus represents a minimum estimate of the total subpopulation. A smaller group of white sturgeon, considered part of the same subpopulation, has been identified at the upper end of Arrow Lakes Reservoir, located upstream from Keenleyside Dam. Estimates place the size of this group at 38 individuals (95% CI = 23 to 78) based on the results of 2000 studies (RL&L 2001). Extensive study has confirmed spawning by upper Columbia white sturgeon at two locations. The vast majority of spawning occurs at the Pend d'oreille Columbia confluence (Waneta tailrace) area near the Canada U.S. border (e.g., RL&L 1995). Spawning at this site has occurred annually since 1993 the first year spawning studies were initiated. In 1999, a second spawning area was documented in the upper Columbia River just upstream from Arrow Lakes Reservoir (RL&L 2000). Spawning did not occur at this site in Despite the regularity of spawning events, age structure analyses show that recruitment began to decline in 1969, and has failed entirely since 1985 (RL&L 1995). Changes in length-frequency distribution follow a similar pattern, with a dramatic reduction in representation by smaller fish in ongoing sampling programs (RL&L 1996a, BC Ministry of Water, Land and Air Protection, data on file). Sampling in Lake Roosevelt in Washington State, although less intensive, shows a similar recruitment failure (DeVore et al. 1999, Spokane Tribe, data on file). Thus, recruitment of upper Columbia white sturgeon has failed completely, to the point where continued existence of the subpopulation is at risk. First maturity is reached as early as 27 years of age for females and 16 for males (RL&L 1995), although the mean age of maturation is likely higher. Assuming a mean age of maturity of 30 years for the subpopulation, and limited or complete failure of recruitment for more than 20 years, at least 80% of the subpopulation is estimated to be of reproductive age. Thus, in combination, the groups of white sturgeon composing this subpopulation would represent about 930 mature individuals. Based on sampling currently underway (B.C. Ministry of Water, Land and Air Protection, data on file) the sex ratio is 1.35 males per female (n=94), indicating 396 females and an effective population size of 910 (Falconer 1981). The oldest documented individual in the subpopulation is 69 years of age. Assuming a typical mortality curve and using age 30 as the point at which maturity is reached, the average age of parents (generation time) in the population is likely years. Current Population Trend: Decreasing Habitat and Ecology (see Appendix for additional information) Restricted to freshwater habitat in the upper Columbia River. Systems: Freshwater Threats (see Appendix for additional information) Upper Columbia white sturgeon were isolated from lower Columbia River stocks in the United States in 1941 following the construction of Grand Coulee Dam and related formation of Lake Roosevelt. Kettle 3

5 Falls in Washington State is thought to have formed a seasonal barrier to white sturgeon migration prior to its inundation by Lake Roosevelt. Construction of Keenleyside, Mica, and Revelstoke dams on the mainstem Columbia River, Brilliant Dam on the lower Kootenay River, and Waneta Dam on the lower Pend d'oreille River further fragmented the population and altered the natural river regime. In addition, the impoundments created by these dams flooded the riverine system, altering or eliminating critical sturgeon habitats, changing water quality and generally reducing system productivity. Dam construction effects were exacerbated by additional impacts such as pollution and waterfront developments. Credits Assessor(s): Reviewer(s): Hammond, J. & Spence, C. (Ministry of Water, Land & Air Protection, Canada) St. Pierre, R. & Pourkazemi, M. (Sturgeon Red List Authority) 4

6 Bibliography Anders, P.J., Gelok, C.R. and Powell, M.S Assessing genetic variation among Columbia Basin white sturgeon populations Annual Report to the Bonneville Power Administration. Project No Portland, OR. Anders, P.J., Gelok, C.R. and Powell, M.S. In prep. Population structure and mitochondrial DNA (mtdna) diversity in North American white sturgeon (Acipenser transmontanus). DeVore, J.D., James, B.W., Gilliland, D.R. and Cady, B.J White sturgeon mitigation and restoration in the Columbia River and Snake River upstream from Bonneville Dam. Report B. Washington Dept. Fish and Wildlife, report prepared for Bonneville Power Administration, Portland, OR. Falconer, D.S Introduction to quantitative genetics. 2nd edition. Longman Group Ltd., Essex, UK. IUCN IUCN Red List of Threatened Species. Downloaded on 23 November RL&L Environmental Services White sturgeon in the Columbia River, B.C study results. Report prepared for BC Hydro, Environmental Affairs, Vancouver, B.C. RL&L Report No. 377D. 74 p. + 4 app. RL&L Environmental Services Columbia River white sturgeon investigations study results. Report prepared for BC Hydro, Kootenay Generation, Vancouver, B.C. and BC Ministry of Environment, Lands and Parks, Kootenay Region. RL&L Report No D. 93 pp.+ 6app. RL&L Environmental Services Ltd Investigations of white sturgeon populations in Revelstoke and Kinbasket reservoirs, 1995 data report. Report prepared for B.C. Ministry of Environment, Lands and Parks, Nelson, B.C. RL&L Report No. 468F RL&L Environmental Services Ltd White sturgeon investigations in Arrow Reservoir and Columbia River, B.C., 1999 study results. Report prepared for B.C. Ministry of Environment, Lands and Parks, Nelson, B.C. RL&L Report No. 754F RL&L Environmental Services Ltd White sturgeon investigations in Arrow Reservoir and the Columbia River, B.C., 2000 study results. Data report prepared for B.C. Ministry of Environment, Lands and Parks, Nelson, B.C. Citation Hammond, J. & Spence, C. (Ministry of Water, Land & Air Protection, Canada). Acipenser transmontanus (Upper Columbia River subpopulation). The IUCN Red List of Threatened Species 2004: e.t44562a 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. 5

7 Appendix Habitats ( Habitat Season Suitability Major Importance? 5. Wetlands (inland) -> 5.1. Wetlands (inland) - Permanent Rivers/Streams/Creeks (includes waterfalls) 5. Wetlands (inland) -> 5.6. Wetlands (inland) - Seasonal/Intermittent Freshwater Lakes (over 8ha) - Suitable - - Suitable - Threats ( Threat Timing Scope Severity Impact Score 1. Residential & commercial development -> 1.1. Housing & urban areas 1. Ecosystem stresses -> 1.1. Ecosystem conversion 1. Residential & commercial development -> 1.2. Commercial & industrial areas 1. Ecosystem stresses -> 1.1. Ecosystem conversion 3. Energy production & mining -> 3.2. Mining & quarrying 1. Ecosystem stresses -> 1.1. Ecosystem conversion 4. Transportation & service corridors -> 4.3. Shipping lanes 5. Biological resource use -> 5.4. Fishing & harvesting aquatic resources -> Intentional use: (subsistence/small scale) Past, unlikely to return 2. Species Stresses -> 2.1. Species mortality 2. Species Stresses -> 2.2. Species disturbance Species Stresses -> 2.1. Species mortality 5. Biological resource use -> 5.4. Fishing & harvesting aquatic resources -> Unintentional effects: (subsistence/small scale) 2. Species Stresses -> 2.1. Species mortality 2. Species Stresses -> 2.2. Species disturbance 7. Natural system modifications -> 7.2. Dams & water management/use -> Dams (size unknown) 1. Ecosystem stresses -> 1.1. Ecosystem conversion 6

8 8. Invasive & other problematic species & genes -> 8.1. Invasive non-native/alien species -> Unspecified species 2. Species Stresses -> 2.1. Species mortality 9. Pollution -> 9.2. Industrial & military effluents -> Type Unknown/Unrecorded Conservation Actions in Place ( Conservation Actions in Place In-Place Research, Monitoring and Planning Systematic monitoring scheme: Yes In-Place Land/Water Protection and Management Conservation sites identified: Yes, over entire range In-Place Species Management Harvest management plan: Yes Subject to ex-situ conservation: Yes Conservation Actions Needed ( 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 -> 3.3. Species re-introduction -> Reintroduction 3. Species management -> 3.4. Ex-situ conservation -> Captive breeding/artificial propagation 4. Education & awareness -> 4.3. Awareness & communications Research Needed ( Research Needed 1. Research -> 1.2. Population size, distribution & trends 7

9 Research Needed 1. Research -> 1.3. Life history & ecology 1. Research -> 1.5. Threats 1. Research -> 1.6. Actions 3. Monitoring -> 3.1. Population trends 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