Effects of river otters on benthic macroinvertebrate populations - PowerPoint PPT Presentation

1 Effects of river otters on benthic macroinvertebrate populations of the Colorado Rocky Mountains Amanda J. Tetz Department of Biology Metropolitan State University of Denver Photo by Victoria Alexander on Unsplash

2 North American River Otter Lontra canadensis th century • Early arly 19 19 th century: first first rec record ord of of ot otte ter ob obse serv rvation ation in in th the st state ate • Fo Found und in in ev every ery ma major jor wate watershed rshed of of th the st state ate of of Co Colo lora rado do Photo by David Groves on Unsplash

3 Bad News for River Otters in Colorado… th & 20 th centuries L. Canadensis nadensis populations pulations declined lined in in th the 19 19 th 20 th turies … Mi Mini ning ng • Agric Ag icult ulture ure • Fu Fur Tr Trap appin ping • State tate End ndan ange gere red d in in 197 1975 [Coryell Coal Mine - Newcastle, Garfield County CO], Retrieved from http://www.miningartifacts.org/Colorado-Mines.html

4 State of Colorado River Otter Recovery Plan Ov Over er 100 100 ot otte ters rs re rele leas ased ed at at fi five ve si site tes ac acro ross ss th the st state ate be betw twee een 1976 1976-1991 1991 https://cpw.state.co.us/Documents/WildlifeSpecies/SpeciesOfConcern/RecoveryPlans/CDOW2003Riverotterrecoveryplan.pdf

5 Species Reintroduction Wolves of Yellowstone Trophic effects caused by Programs wolves in Yellowstone include: Elk pop’n Aspen & Cottonwood recruitment Beaver & Bison pop’ns Frank, J.W. (n.d). [Wolf portrait taken from a vehicle in a pullout]. Retrieved from https://www.nps.gov/media/photo/gallery-item.htm?pg=0&id=cebbfa91-94e3-4e62-bf1d-1dca050c5d5f&gid=25C97BD8- 155D-451F-675E208BE082FE26

6 Has reintroduction of L. canadensis caused similar trophic effects? Reestablishment of otter populations … fish populations macroinvertebrate populations [BugsinDish] Retrieved from https://dep.wv.gov/WWE/watershed/bio_fish/Pages/Bio_Fish.aspx

Based on reported otter sightings… 7 Five sites selected along 29.7 km stretches of two Rocky Mountain rivers • Colorado River (Between Dotsera & Glenwood Springs) • Roaring Fork River (Between Basalt & Aspen) Two river-bottom samples collected at each site Photo credit: Brad Samuels

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In Inta tact ct ma macr croi oinve nvertebra rtebrates tes 9 fr from om ea each ch ri rive ver r sa samp mple le we were re counted… Colorado River x ̄ count = 132.6 SD count = 62.5 x̄ temp = 8.1 °C Sd temp = 0.2 °C Factor p Roaring Fork River River 0.249 x ̄ count = 100.2 SD count = 55.3 Temp 0.476 x̄ temp = 8.3 °C River:Temp 0.461 SD temp = 0.7 °C

What can we 10 learn? Photo credit: Brad Samuels Su Substrate bstrate Di Diffe fferences rences Diet Die t of of L. L. Can Canaden adensis sis Fl Fly Fi y Fishing shing [Finalist_Fryingpan-River-East-of-Basalt]. Retrieved from: https://coloradowatertrust.org/project/wheeler-ditch

11 Entomopathogenic Nematodes Greb, P. (n.d). [entomopathogenic nematode (Heterorhabditis bacteriophora)]. Retrieved from: https://www.forestryimages.org/browse/detail.cfm?imgnum=1316021

12 [w631933162]. Retrieved from: https://columbiametro.com/article/utterly-otters/

13 Acknowledgements Sincerest thanks to… • MSU Denver Department of Biology • Mr. Christopher Cooley • My husband, Brad Samuels for all his support, assistance with sample collection, photography, and co- parenting during this project! [River-Otter]. Retrieved from: https://hhltmaine.org/nature-notes/nature-notes-river-otters/

14 Send any questions to: atetz@msudenver.edu Literature Cited Adams B.J., Nguyen K.B. (2008). Nematode Parasites of Insects. In: Capinera J.L. (eds) Encyclopedia of Entomology. Springer, Dordrecht Armstrong D. M. (1972). Distribution of mammals in Colorado . (Vol. 3). U of KA Printing Service. Berg, J. K. (1999). Final Report of the River Otter Research Project on the Upper Colorado River Basin in and Adjacent to Rocky Mountain National Park, Colorado . Colorado Division of Wildlife. (2003). State of Colorado River Otter Recovery Plan (Issue June). https://cpw.state.co.us/Documents/WildlifeSpecies/SpeciesOfConcern/RecoveryPlans/CDOW2003Riverotterrecoveryplan.pdf Ripple, W. J., & Beschta, R. L. (2012). Trophic cascades in Yellowstone: The first 15 years after wolf reintroduction . Biological Conservation, 145, 205 – 213.