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Yvette K. Ortega

Yvette K. Ortega
Wildlife and Terrestrial Ecosystems
800 East Beckwith Avenue
Missoula, MT 59801-5801
United States
Current Research
* Evaluate invader impacts at population and community levels, including underlying mechanisms. * Examine interactive impacts of drought and herbivory by biological control agents on the competitive dominance of a notorious weed. * Assess a new technique for assessing habitat quality for songbirds based on local song structure. * Measure effects of invasive plant control treatments on plants and animals and evaluate degree to which such methods mitigate target invader impacts.
Past Research

My past research includes examination of disturbance effects on harbor seals, edge effects of forest roads on songbirds, and habitat use of Canada lynx.

Research Interest
My primary interest lies in building understandings of ecological patterns and processes in order to improve the management of natural systems. Current applications include evaluating impacts of exotic plants on native plants, cascading effects on consumers, and efficacy of weed control efforts in mitigating these impacts. Studies consider population and community level attributes, and organisms from plants and invertebrate to birds and their predators.
Why This Research Is Important

My work aims to develop and apply ecological principles to solve real-world problems facing managers of natural systems.

  • University of California, Berkeley, B.A., Environmental Science, 1992
  • University of Vermont, M.S., Wildlife and Fisheries Biology, 1998
Featured Publications
Other Publications
Research Highlights

An herbicide solution to knapweed

Year: 2011
Station researchers evaluated the effects of a common herbicide treatment on grassland plants in western Montana to determine if and when suppression of spotted knapweed may relieve impacts of this notorious invader

Invasive Plant Erodes Bird Song Diversity via Food Chain Effects

Year: 2015
Although plant invaders are known for their negative effects on natural systems, the extent of these impacts is often unknown. Forest Service scientists studied how invasion of spotted knapweed (Centaurea stoebe) into grasslands of western Montana impacted native species from plants to insects to b...

The Bane of Weed Management: Secondary Invasions

Year: 2016
Weed management can result in unintentional secondary invasion: an increase in non-target exotics following efforts to suppress targeted invasive plants. Meta-analysis showed that management efforts strongly reduced target invader abundance overall; however, secondary invaders increased following co...

The tortoise and the hare: Can the slow native plant win?

Year: 2017
It has been suggested that exotic plants will be more successful than native plant species as a result of climate change. This is because exotics often exhibit stronger responses to disturbance, faster growth rates, and greater plasticity. In this study, we show that climate change can actually shif...

Invasiveness and Impact of 48 Exotic Plant Species in Native Grasslands

Year: 2015
This study quantified and ranked invasiveness and impact for 48 exotic plant species based on surveys over 20,000 square kilometers (12,427 square miles) of grasslands in western Montana. These data provide a valuable tool for managers to determine the relative impacts of invaders for prioritizing e...