River Otters in Yellowstone Lake Depend on a Declining Cutthroat Trout Population

Crait, Jamie R.; Ben‐David, Merav

doi:10.1644/05-mamm-a-205r1.1

Cited by 38 publications

(54 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Unlike these fish, cutthroat trout may spawn several times during their life (Gresswell 1995). Spawning mortality varied between 13 and 31% in tributary streams of Yellowstone v www.esajournals.org Lake, but nutrients from decaying cutthroat trout carcasses probably had small effects on streams because river otters (Lontra canadensis) and grizzly bears (Ursus arctos horribilis) consume cutthroat trout (Crait andBen-David 2006, Fortin et al 2013), and we never observed carcasses decomposing in streams (L. Tronstad, personal observation). Similar to iteroparous suckers with low spawning mortality (Childress et al 2014), excretion fluxes were likely the major nutrient source from spawning cutthroat trout.…”

Section: Nhmentioning

confidence: 64%

“…Furthermore, isotopic evidence from studies of migrating fish showed that transported nutrients were incorporated into all trophic levels, including primary producers, invertebrates, and fish (Bilby et al 1996, Childress et al 2014. Finally, declining cutthroat trout in Yellowstone National Park negatively affected terrestrial and semi-aquatic predators such as osprey (Pandion haliaetus; Baril et al 2013), river otters (Crait and Ben-David 2006), and grizzly bears , Teisberg et al 2014. The effects of fewer cutthroat trout may extend far from Yellowstone Lake because bears are eating more elk calves as spawning cutthroat trout become more scarce (Middleton et al 2013).…”

Section: Nhmentioning

confidence: 99%

See 1 more Smart Citation

Introduced lake trout alter nitrogen cycling beyond Yellowstone Lake

2015

View full text Add to dashboard Cite

Citation: Tronstad, L. M., R. O. Hall Jr., and T. M. Koel. 2015. Introduced lake trout alter nitrogen cycling beyond Yellowstone Lake. Ecosphere 6(11):224. http://dx.doi.org/10.1890/ES14-00544.1Abstract. Introduced predators can have large effects on the ecosystem in which they were introduced, but how much these effects extend to other ecosystems beyond the invaded one is less known. We compared how lake trout (Salvelinus namaycush) affected nutrient cycling in an invaded and adjacent ecosystem in Yellowstone National Park, Wyoming, USA. Introduced lake trout in Yellowstone Lake caused the native Yellowstone cutthroat trout (Oncoryhynchus clarkii bouvieri ) population to decline. Native cutthroat trout are a dominant animal in the lake and may alter nutrient cycling in both Yellowstone Lake where they reside and in tributary streams used for spawning. We estimated changes in nutrient transport and nutrient uptake in both Yellowstone Lake and Clear Creek, a spawning stream, before and after the invasion of lake trout. Annual area-specific excretion fluxes from cutthroat trout were nine times higher in Clear Creek compared to Yellowstone Lake when cutthroat trout were abundant. However, fluxes within the lake and stream were similar after cutthroat trout declined. In Yellowstone Lake, zooplankton excretion supplied 86% of ammonium (NH 4 þ ) that was taken up, but cutthroat trout only supplied ,0.3% after the introduction of lake trout. Conversely, NH 4 þ excreted by cutthroat trout was likely a major flux in ClearCreek, because NH 4 þ fluxes from cutthroat trout exceeded watershed export of NH 4 þ in years when .3000 cutthroat trout spawned. Furthermore, NH 4 þ excretion fluxes from spawning cutthroat trout in ClearCreek supplied up to 6.1% of the NH 4 þ demanded by microbes after the introduction of lake trout.However, based on modeled past NH 4 þ uptake, we estimated that up to 60% of NH 4 þ excreted by spawning cutthroat trout may have been taken up by stream microbes when cutthroat trout were abundant. Therefore, transported NH 4 þ from spawning cutthroat trout was likely an integral part of N cycling in tributary streams in the past. By comparing the effects of declining cutthroat trout on two ecosystems, we show that lake trout had a larger effect on N cycling within an adjacent stream ecosystem than the invaded lake ecosystem itself, because the migratory behavior of cutthroat trout concentrated them in spawning streams increasing their effect.

show abstract

Section: Nhmentioning

confidence: 64%

Section: Nhmentioning

confidence: 99%

Introduced lake trout alter nitrogen cycling beyond Yellowstone Lake

2015

View full text Add to dashboard Cite

show abstract

“…However, for otters in Yellowstone Lake, the challenge of successfully foraging at altitude has been heightened by a recent population decline in the native cutthroat trout, Oncorhynchus clarki bouvieri (Koel et al, 2005). Cutthroat trout are important prey for otters in Yellowstone Lake, and during the spawning season provide an accessible and lipid-rich food source (Crait and Ben-David, 2006). For otters in this ecosystem, the only comparable alternative prey is the recently introduced lake trout (Salvelinus namaycush).…”

Section: Introductionmentioning

confidence: 99%

High-altitude diving in river otters: coping with combined hypoxic stresses

Crait

Prange

Marshall

et al. 2012

Journal of Experimental Biology

Self Cite

View full text Add to dashboard Cite

SUMMARY River otters (Lontra canadensis) are highly active, semi-aquatic mammals indigenous to a range of elevations and represent an appropriate model for assessing the physiological responses to diving at altitude. In this study, we performed blood gas analyses and compared blood chemistry of river otters from a high-elevation (2357 m) population at Yellowstone Lake with a sea-level population along the Pacific coast. Comparisons of oxygen dissociation curves (ODC) revealed no significant difference in hemoglobin-oxygen (Hb-O2) binding affinity between the two populations - potentially because of demands for tissue oxygenation. Instead, high-elevation otters had greater Hb concentrations (18.7 g dl-1) than sea-level otters (15.6 g dl-1). Yellowstone otters displayed higher levels of the vasodilator nitric oxide (NO), and half the concentration of the serum protein albumin, possibly to compensate for increased blood viscosity. Despite compensation in several hematological and serological parameters, theoretical aerobic dive limits (ADL) were similar between high-elevation and sea-level otters because of the lower availability of O2 at altitude. Our results suggest that recent disruptions to the Yellowstone Lake food web could be detrimental to otters because at this high elevation, constraints on diving may limit their ability to switch to prey in a deep-water environment.

show abstract

“…There is very little information, however, relating the location and habitat features of latrine sites to spatial and temporal variation in their use. The exceptions are the use of deposition rates at latrine sites to document differences in latrine use between lake and stream habitats during the spring and summer (Crait and Ben-David 2006), and to investigate coarse-scale differences in the use of beaver ponds or wetland types (Leblanc et al 2007;Newman and Griffin 1994). Variation in latrine-site use among seasons has also been documented for Eurasian otters in Finland (Sulkava 2006).…”

Section: Introductionmentioning

confidence: 99%

“…The authors documented seasonal movements by otters to abundant food resources such as kokanee (Oncorhynchus nerka) spawning grounds. In Yellowstone Lake, otters also appeared to make movements in direct relation to the timing of spawning cutthroat trout {Oncorhynchus clarki) (Crait and Ben-David 2006).…”

mentioning

confidence: 99%

Patterns of river otter (Lontra canadensis) diet and habitat selection at latrine sites in central British Columbia.

Crowley¹

View full text Add to dashboard Cite

River Otters in Yellowstone Lake Depend on a Declining Cutthroat Trout Population

Cited by 38 publications

References 30 publications

Introduced lake trout alter nitrogen cycling beyond Yellowstone Lake

Introduced lake trout alter nitrogen cycling beyond Yellowstone Lake

High-altitude diving in river otters: coping with combined hypoxic stresses

Patterns of river otter (Lontra canadensis) diet and habitat selection at latrine sites in central British Columbia.

Contact Info

Product

Resources

About