Treesearch

Many systems are prone to both exotic plant invasion and frequent natural disturbances. Native species richness can buffer the effects of invasion or disturbance when imposed in isolation, but it is largely unknown whether richness provides substantial resistance against invader impact in the face of disturbance. We experimentally examined how disturbance (drought/burning) influenced the impact of three exotic invaders (Centaurea stoebe, Linaria dalmatica, or Potentilla recta) on native abundance across a gradient of species richness, using previously constructed grassland assemblages. We...

Caragana, with distinctive variation in leaf and rachis characters, exhibits three centers of geographic distribution, i.e., Central Asia, the Qinghai-Tibetan Plateau (QTP), and East Asia, corresponding to distinct biomes. Because Caragana species are often ecologically dominant components of the vegetation in these regions, it is regarded as a key taxon for the study of floristic evolution in the dry regions of temperate Asia. Based on an expanded data set of taxa and gene regions from those previously generated, we employed molecular clock and biogeographical analyses to infer the...

Monarch butterflies (Danaus plexippus), other pollinators, and Greater Sage-Grouse (Centrocercus urophasianus) are currently the focus of increased conservation efforts. Federal attention on these fauna is encouraging land managers to develop conservation strategies, often without corresponding financial resources. This could foster a myopic approach when allocating resources and setting restoration priorities, and at best, allow for inefficiencies in the usage of land management resources, or, at worst, pit one species (or suite of species, e.g., pollinators) against another (e.g.,...

The primary goals of a two-day Russian olive symposium held in February 2014 were to disseminate current knowledge and identify data gaps regarding Russian olive biology and ecology, distributions, integrated management, and to ascertain the feasibility and acceptance of a proposed program for classical biological control of Russian olive. The symposium was hosted by the Northern Rockies Invasive Plant Council in conjunction with NRIPC’s 3rd Invasive Species in Natural Areas Conference, held February 10-15, 2014, in Spokane, WA. Funding to support the Russian olive symposium was received...

An online survey was distributed through email lists provided by various stakeholder groups on behalf of the International Consortium for Biological Control of Russian Olive in spring of 2012. A total of 392 respondents replied from 24 U.S. states and 1 Canadian province. Questions posed in the survey were designed to identify and categorize 1) stakeholders by geographic location, profession and professional affiliation; 2) stakeholder perceptions of Russian olive as a problematic and/or beneficial organism; 3) by ecological, economic and geographic scale stakeholders’ perceived benefits...

Traditional knowledge about fire and its effects held by indigenous people, who are connected to specific landscapes, holds promise for informing contemporary fire and fuels management strategies and augmenting knowledge and information derived from western science. In practice, however, inadequate means to organize and communicate this traditional knowledge with scientists and managers can limit its consideration in decisions, requiring novel approaches to interdisciplinary and cross-cultural communication and collaboration. We propose that Participatory Geographic Information Systems...

The recent development of an interagency strategy to monitor wilderness character allows on-the-ground managers and decision-makers to assess whether stewardship actions for an individual wilderness are fulfilling the legislative mandate to "preserve wilderness character." By using credible data that are consistently collected, one can assess how wilderness character changes over time and evaluate how stewardship actions affect trends in wilderness character. As most of these data depict spatial or geographic features in wilderness, a Geographic Information System (GIS) -based approach was...

Aim: The purpose of this study was to examine the influence of moisture and fire on historical ponderosa pine (Pinus ponderosa Dougl. ex Laws.) age structure patterns. Location: We used a natural experiment created over time by the unique desert island geography of southern Arizona. Methods: We sampled tree establishment dates in two sites on Rincon Peak and another site in the Santa Catalina Mountains. The influence of regional moisture patterns was investigated by examining synchrony among tree age peaks and periods of favourable moisture. The influence of fire was investigated by...

The geography of the Black Hills region of South Dakota and Wyoming may limit connectivity for many species. For species with large energetic demands and large home ranges or species at low densities this can create viability concerns. Carnivores in this region, such as cougars (Puma concolor), have the additive effect of natural and human-induced mortality; this may act to decrease long-term viability. In this study we set out to explore genetic diversity among cougar populations in the Black Hills and surrounding areas. Specifically, our objectives were to first compare genetic variation...

The difficulty of collecting occurrence and population dynamics data in mammalian populations of low density poses challenges for making informed management decisions. We assessed the use of scat-detection dogs to search for fecal pellets in a low density moose (Alces alces) population in the Adirondack Park in New York State, and the success rate of DNA extraction from moose fecal pellets collected during the surveys. In May 2008, two scat-detection dog teams surveyed 20, 4-km transects and located 138 moose scats. In 2011 we successfully amplified DNA from 39 scats (28%) and were able to...