Migration of green sturgeon, Acipenser medirostris, in the Sacramento River

AbstractBackgroundUnderstanding movement patterns of anadromous fishes is critical to conservation management of declining wild populations and preservation of habitats. Yet, infrequent observations of individual animals fundamentally constrain accurate descriptions of movement dynamics.MethodsIn this study, we synthesized over a decade (2006–2018) of acoustic telemetry tracking observations of green sturgeon (Acipenser medirostris) in the Sacramento River system to describe major anadromous movement patterns.ResultsWe observed that green sturgeon exhibited a unimodal in-migration during the spring months but had a bimodal distribution of out-migration timing, split between an ‘early’ out-migration (32%) group during May - June, or alternatively, holding in the river until a ‘late’ out-migration (68%), November - January. Focusing on these out-migration groups, we found that river discharge, but not water temperature, may cue the timing of migration, and that fish showed a tendency to maintain out-migration timing between subsequent spawning migration events.ConclusionsWe recommend that life history descriptions of green sturgeon in this region reflect the distinct out-migration periods described here. Furthermore, we encourage the continued use of biotelemetry to describe migration timing and life history variation, not only this population but other green sturgeon populations and other species.

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Behavior, movements, and habitat use of adult green sturgeon, Acipenser medirostris, in the upper Sacramento River

Environmental Biology of Fishes ◽

10.1007/s10641-013-0132-8 ◽

2013 ◽

Vol 97 (2) ◽

pp. 133-146 ◽

Cited By ~ 10

Author(s):

Michael J. Thomas ◽

Matthew L. Peterson ◽

Eric D. Chapman ◽

Alex R. Hearn ◽

Gabriel P. Singer ◽

...

Keyword(s):

Habitat Use ◽

Sacramento River ◽

Green Sturgeon ◽

Acipenser Medirostris

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Fine-scale habitat selection of green sturgeon (Acipenser medirostris) within three spawning locations in the Sacramento River, California

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2017-0072 ◽

2018 ◽

Vol 75 (5) ◽

pp. 779-791 ◽

Cited By ~ 6

Author(s):

M.T. Wyman ◽

M.J. Thomas ◽

R.R. McDonald ◽

A.R. Hearn ◽

R.D. Battleson ◽

...

Keyword(s):

Habitat Suitability ◽

Sacramento River ◽

Habitat Characteristics ◽

Physical Habitat ◽

Fine Scale ◽

Green Sturgeon ◽

Acipenser Medirostris ◽

Area Index ◽

Spawning Period ◽

National Marine Fisheries Service

Vast sections of the Sacramento River have been listed as critical habitat by the National Marine Fisheries Service for green sturgeon spawning (Acipenser medirostris), yet spawning is known to occur at only a few specific locations. This study reveals the range of physical habitat variables selected by adult green sturgeon during their spawning period. We integrated fine-scale fish positions, physical habitat characteristics, discharge, bathymetry, and simulated velocity and depth using a two-dimensional hydraulic model (FaSTMECH). The objective was to create habitat suitability curves for depth, velocity, and substrate type within three known spawning locations over two years. An overall cumulative habitat suitability score was calculated that averaged the depth, velocity, and substrate scores over all fish, sites, and years. A weighted usable area index was calculated throughout the sampling periods for each of the three sites. Cumulative results indicate that the microhabitat characteristics most preferred by green sturgeon in these three spawning locations were velocities between 1.0 and 1.1 m/s, depths of 8–9 m, and gravel and sand substrate. This study provides guidance for those who may in the future want to increase spawning habitat for green sturgeon within the Sacramento River.

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Biology, Management, and Protection of North American Sturgeon

Biology, Management, and Protection of North American Sturgeon ◽

10.47886/9781888569360.ch19 ◽

2002 ◽

Keyword(s):

Growth Rate ◽

Incubation Temperature ◽

Larval Survival ◽

Sampling Time ◽

White Sturgeon ◽

Green Sturgeon ◽

Acipenser Medirostris ◽

Relative Growth ◽

Klamath River ◽

Length Relationship

Abstract.—Gametes of green sturgeon Acipenser medirostris (caught in the Klamath River, California) and farm-reared white sturgeon A. transmontanus were obtained using hormonal induction of ovulation and spermiation. The offspring of one female in each species were reared in the laboratory, to compare their development and growth. Green and white sturgeon embryos had similar rates of development and hatched after 169 h and 176 h, respectively, at incubation temperature 15.7 ± 0.2°C. Embryos of both species exhibited similar holoblastic development and passed through 36 stages characteristic of acipenserids. Green sturgeon fertilization and hatching rates were 41.2% and 28.0%, compared with 95.4% and 82.1% for the white sturgeon. Larval survival to 45 d (metamorphosis) was 93.3% in green and 92.1% in white sturgeon. Newly hatched green sturgeon (length 13.7 ± 0.4 mm, mean ± SD) were larger and less pigmented, compared with white sturgeon. They had large ovoid yolk sacs and did not exhibit pelagic behavior that was observed in white sturgeon. The onset of exogenous feeding in green sturgeon occurred at age 10–15 d and length 24.0 ± 0.5 mm, and metamorphosis was completed at age 45 d and length 74.4 ± 5.9 mm (rearing temperature 18.5 ± 0.2°C). Weight and length of green sturgeon larvae and juveniles were considerably greater than in white sturgeon at each sampling time, but the relative growth rate and weight-length relationship were similar in both species. This suggests an effect of larger egg size and maternal yolk supply on the growth of green sturgeon. We conclude that green sturgeon differs from the white sturgeon in their reproductive strategy and, potentially, reproductive habitat.

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