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Research about Yellowstone Lake

Source-linked reports with geographic coverage including Yellowstone Lake.

26 records · Page 2Linked to original sources

Organic pellet decomposition induces mortality of Lake Trout embryos in Yellowstone Lake

Yellowstone Lake is the site of actions to suppress invasive Lake Trout Salvelinus namaycush and restore native Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri and natural ecosystem function. Although gill netting is effective (Lake Trout λ ≤ 0.6 from 2012 through 2018), the effort costs more than US$2 million annually and only targets Lake Trout age 2 and older. To increase suppression efficiency, we developed an alternative method using organic (soy and wheat) pellets to increase mortality of Lake Trout embryos on spawning sites. Decomposition of pellets during two in situ experiments caused dissolved oxygen (DO) concentrations to temporarily decline to lethal levels (<3.4 mg/L) within days of application. Embryo mortalities during the first exposure period (days 1–6 following application) were high at all treatment levels (1.75–28.0 kg/m 2 ) at the substrate surface and within interstices 20 cm below the surface, varying from 97 ± 1.8% (mean ± SE) to 100 ± 0.0%, but may have been enhanced by a handling effect (exposure to sunlight). Embryo mortalities during the second exposure period (days 11–22) were highest 20 cm below the surface, varying from 78 ± 9.7% to 100 ± 0.0%. Almost all (98 ± 3.1%) Lake Trout embryos died after exposure to DO < 3.4 mg/L for >200 h during the second period. Pellets caused lethal DO for several weeks below the substrate surface, despite largely dissolving and dissipating from the surface of treated areas by day 39. Broad-scale application of pellets at 1.75 kg/m 2 following the spawning period in autumn may reduce Lake Trout recruitment and enhance population suppression because the area of 14 verified spawning sites is only 11.4 ha (0.03% of lake surface area). Pellet application may be useful in other similar systems as part of an integrated pest management approach targeting multiple life stages of invasive freshwater fish.

Wyoming

In situ evaluation of benthic suffocation methods for suppression of invasive Lake Trout embryos in Yellowstone Lake

Suppression of invasive Lake Trout Salvelinus namaycush is an important management tool to use in native fish and ecosystem conservation throughout the U.S. Intermountain West. Lake Trout suppression, primarily by gill netting, has been ongoing in Yellowstone Lake, Yellowstone National Park, Wyoming, since 1995. Additional methods that cause mortality of Lake Trout embryos could be used simultaneously with gill netting to enhance suppression. Our objective was to evaluate the in-situ efficacy of two benthic suffocation methods—tarping with gas-impermeable tarps and Lake Trout carcass deposition to increase the mortality of Lake Trout embryos. Tarping did not increase embryo mortality; mean control mortality was 21 ± 1.9% (mean ± SE), and mean tarp-treatment mortality was 20 ± 2.9%. Lake Trout carcass deposition caused 98 ± 1.2% mean mortality of embryos at the substrate surface and 100 ± 0.1% mean mortality of embryos 20 cm below the substrate surface. Hypoxic conditions in the carcass treatments were probably the cause of the high embryo mortality; dissolved oxygen concentrations at the substrate surface declined from 7.74 to 0.06 mg/L when carcasses remained on the treatment locations. The deposition of Lake Trout carcasses shows potential to be an additional suppression method that can induce mortality in Lake Trout embryos through benthic suffocation and could be implemented at Lake Trout spawning sites in Yellowstone Lake.

Wyoming

Myxobolus cerebralis in native cutthroat trout of the Yellowstone Lake ecosystem

The exotic parasite Myxobolus cerebralis was first detected in native adult Yellowstone cutthroat trout Oncorhynchus clarkii bouvierii from Yellowstone Lake in 1998, seriously threatening the ecological integrity of this pristine, naturally functioning ecosystem. We immediately began to assess the prevalence and spatial extent of M. cerebralis infection in Yellowstone cutthroat trout within Yellowstone Lake and to determine the infection risk of age-0 Yellowstone cutthroat trout, the relative abundance and actinospore production of lubificid worms, and the basic environmental characteristics of tributaries. During 1999-2001, juvenile and adult Yellowstone cutthroat trout were infected throughout Yellowstone Lake; the highest prevalence (15.3-16.4%) occurred in the northern and central regions. Exposure studies in 13 streams indicated that Pelican and Clear creeks and the Yellowstone River were positive for M. cerebralis; the highest prevalence (100%) and severity was found in Pelican Creek during mid-July. Sexually mature individuals of the oligochaete Tubifex tubifex were most abundant in early summer, were genetically homogenous, and were members of a lineage known to produce moderate to high levels of M. cerebralis triactinomyxons. Only 20 of the 3,037 sampled tubificids produced actinospores after 7 d in culture, and none of the actinospores were M. cerebralis. However, one non-actinospore-producing T. tubifex from Pelican Creek tested positive for M. cerebralis by polymerase chain reaction. Stream temperatures at Pelican Creek, a fourth-order, low-gradient stream, were over 20??C during the first exposure period, suggesting that T. tubifex were capable of producing triactinomyxons at elevated temperatures in the wild. Although the infection of otherwise healthy adult Yellowstone cutthroat trout within Yellowstone Lake suggests some resistance, our sentinel cage exposures indicated that this subspecies may be more susceptible to whirling disease than previous laboratory challenges have indicated, and M. cerebralis may be contributing to a significant recent decline in this population. ?? Copyright by the American Fisheries Society 2006.

Wyoming

Hydrothermal vent fluids, siliceous hydrothermal deposits, and hydrothermally altered sediments in Yellowstone Lake

Stable isotopic (dD and d18O) data indicate about 13% total evaporative concentration has occurred in Yellowstone Lake, yet lake waters are enriched in dissolved As, B, Cl, Cs, Ge, Li, Mo, Sb, and W by at least an order-of-magnitude relative to the flow-weighted composition of inflowing streams. We conclude that lake water is a mixture of inflowing surface water and hydrothermal source fluid that is strongly enriched in Cl and other elements. We estimate that ~10% of the total hydrothermal flux in Yellowstone National Park (YNP) occurs in Yellowstone Lake. Geochemical and mineralogical studies of hydrothermal deposits and hydrothermally altered lake sediments (vent muds) from the active or recently active vent sites on the floor of Yellowstone Lake indicate that their formation is due to hydrothermal fluid quenching during flow through shallow conduits, or to mixing upon egress into cold bottom waters. Siliceous precipitates form conduits within the uppermost sediments, tabular deposits along sedimentary layers, and spires up to 8 m tall. These deposits are enriched in As, Cs, Hg, Mo, Sb, Tl and W. Spires, vent deposits, and conduits contain filamentous microstructures that probably represent silicified bacteria. Partly recrystallized and silicified diatoms are abundant in deposits below the sediment-water interface. Vent muds and some outer conduit walls show pervasive leaching of silica, which explains the occurrence of most sublacustrine vents in craters. Systematics of dD and Cl variations, as well as silica and cation geothermometry for hydrothermal fluids, suggest that ascending fluids boil due to depressurization to a temperature of ~220°C and then mix with pore waters prior to venting on the lake bottom. Depositional temperatures for sublacustrine silica deposits, calculated using oxygen isotope fractionation, range from 78°C to 164°C. The amorphous silica-saturated vent fluids precipitate silica to form spires or conduits largely by conductive cooling. Bacterial accumulations may have inhibited the mixing of vent fluids and bottom waters, and provided a site for silica deposition.

Wyoming

Effects of the wildfire on growth of cutthroat trout in Yellowstone Lake

This chapter discusses the effects of wildfire on the growth of cutthroat trout in Yellowstone Lake. Trends in year-to-year variation in growth for individual age groups and 25 mm length groups of cutthroat trout in Yellowstone Lake were examined in an attempt to detect shifts in growth patterns associated with the fires. Approximately 100,000 ha of the Yellowstone Lake watershed burned between early July and late August 1988 and the majority of area burned was in the southern part of the drainage, including the Yellowstone River, the largest tributary to the lake. Pelican Creek, the second largest tributary to the lake, was the only major tributary entering the lake from the north that was affected by the fire. In order to aid interpretation of trends through time, relative growth rates of cutthroat trout in individual age and length groups were evaluated using linear regression.

Wyoming

Influence of basin-scale physical variables on life history characteristics of cutthroat trout in Yellowstone Lake

Individual spawning populations of Yellowstone cutthroat trout Oncorhynchus clarki bouvieri differ in life history characteristics associated with broad spatial and temporal environmental patterns, but relationships between specific life history characteristics of Yellowstone cutthroat trout and physical aspects of the environment are poorly understood. We examined basin-scale physical characteristics of tributary drainages and subbasins of Yellowstone Lake in relation to timing (peak and duration) of lacustrine–adfluvial Yellowstone cutthroat trout spawning migrations and mean length of cutthroat trout spawners in 27 tributaries to the lake. Stream drainages varied along gradients that can be described by mean aspect, mean elevation, and drainage and stream size. Approximately two-thirds of the variation in the timing of the peak of the annual cutthroat trout spawning migrations and average length of spawners was explained by third-order polynomial regressions with mean aspect and basin area as predictor variables. Because most cutthroat trout ascend tributaries soon after peak runoff, it appears that the influence of basin-scale physical variables on the date of the migration peak is manifested by the pattern of stream discharge. Spawner length does not seem to be a direct function of stream size in the Yellowstone Lake watershed, and aspect of the tributary basin seems to have a greater influence on the body length of cutthroat trout spawners than does stream size. Mechanisms that explain how the interaction of basin-scale physical variables influence spawner length were not investigated directly; however, we found evidence of distinct aggregations of cutthroat trout that are related to physical and limnological characteristics of the lake subbasins, and there is some indication that lake residence may be related to tributary location.

Wyoming