Publications

The U.S. Army Corps of Engineers (USACE) operates the Willamette Valley Project (Project) in northwestern Oregon, which includes a series of dams, reservoirs, revetments, and fish hatcheries. Project dams were constructed during the 1950s and 1960s on rivers that supported populations of spring Chinook salmon (Oncorhynchus tshawytscha), winter steelhead (O. mykiss), and other anadromous...

Our study represents the first attempt to describe biogeographic provinces for North American (México, United States, and Canada) turtles. We analyzed three nested data sets separately: (1) all turtles, (2) freshwater turtles, and (3) aquatic turtles. We georeferenced North American turtle distributions, then we created presence–absence matrices for each of the three data sets. We used...

Among the most pressing concerns of land managers in post-wildfire landscapes are the establishment and spread of invasive species. Land managers need accurate maps of invasive species cover for targeted management post-disturbance that are easily transferable across space and time. In this study, we sought to develop an iterative, replicable methodology based on limited invasive species

Barrier islands are dynamic environments due to their position at the land-sea interface. Storms, waves, tides, currents, and relative sea-level rise are powerful forces that shape barrier island geomorphology and habitats (for example, beach, dune, marsh, and forest). Hurricane Katrina in 2005 and the Deep Water Horizon oil spill in 2010 are two major events that have affected habitats...

Summary Great Lakes fishery managers have the opportunity and have expressed interest in reestablishing a native forage base in the Great Lakes consisting of various forms and species within the genus Coregonus. This report summarizes the proceedings of a workshop focused on a subset of the genus, and the term “coregonines” is used to refer to several species of deepwater ciscoes (also...

An individual's investment in constitutive immune defenses depends on both intrinsic and extrinsic factors. We examined how Leucocytozoon parasite presence, body condition (scaled mass), heterophil-to-lymphocyte (H:L) ratio, sex, and age affected immune defenses in golden eagle (Aquila chrysaetos) nestlings from three regions: California, Oregon, and Idaho. We quantified hemolytic...

Monitoring species in National Parks facilitates inference regarding effects of climate change on population dynamics because parks are relatively unaffected by other forms of anthropogenic disturbance. Even at early points in a monitoring program, identifying climate covariates of population density can suggest vulnerabilities to future change. Monitoring landbird populations in parks...

Wildfire and the threat it poses to society represents an example of the complex, dynamic relationship between social and ecological systems. Increasingly, wildfire adaptation is posited as a pathway to shift the approach to fire from a suppression paradigm that seeks to control fire to a paradigm that focuses on “living with” and “adapting to” wildfire. In this study, we seek insights...

Altitudinal movement by tropical birds to track seasonally variable resources can move them from protected areas to areas of increased vulnerability. In Hawaiʻi, historical reports suggest that many Hawaiian honeycreepers such as the ‘I‘iwi (Drepanis coccinea) once undertook seasonal migrations, but the existence of such movements today is unclear. Because Hawaiian honeycreepers are...

Scenario planning helps managers incorporate climate change into their natural resource decision making through a structured “what-if” process of identifying key uncertainties and potential impacts and responses. Although qualitative scenarios, in which ecosystem responses to climate change are derived via expert opinion, often suffice for managers to begin addressing climate change in...

The colonization of urban environments by animals is often accompanied by earlier breeding and associated changes in seasonal schedules. Accelerated timing of seasonal reproduction in derived urban populations is a potential cause of evolutionary divergence from ancestral populations if differences in physiological processes that regulate reproductive timing become fixed over time. We...

The eastern migratory population of monarch butterflies (Danaus plexippus plexippus) has declined by >80% within the last two decades. One possible cause of this decline is the loss of ≥1.3 billion stems of milkweed (Asclepias spp.), which monarchs require for reproduction. In an effort to restore monarchs to a population goal established by the US Fish and Wildlife Service and adopted...