We describe the singing behavior of Yellow-rumped Warblers (Setophaga coronata) in southern Oregon. Males used songs of 2 categories. Type I songs were delivered early in the breeding season before females were observed, and differed from the Type II songs delivered in low-light conditions before sunrise after the arrival of females. Both Type I and Type II songs were used after the dawn chorus. Chip-like call notes did not accompany Type II singing in the dawn chorus unlike some warblers with 2 song categories. Both Type I and Type II songs varied considerably among males, and song sharing was uncommon. Songs of Yellow-rumped Warblers were performance encoded; no obvious features with respect to frequency, duration, or syllable structure united the songs within each song category. Unlike many warblers with performance-encoded songs, Type II song bouts of a given male consisted of a single variant.

I conducted a literature review of Harbor Seal dietary composition within the northern California Current Large Marine Ecosystem (CCLME). Papers examining quantitative dietary information from stomach contents and fecal hard-part analyses were used to create a comprehensive list of Harbor Seal prey in the northern California Current System. The study regions included Washington, Oregon, and the Columbia River, and were divided by Harbor Seal stock. Fourteen papers from the years 1931 to 2013 were compiled to obtain a comprehensive and quantitative evaluation of Harbor Seal dietary composition. Harbor Seals consumed a seasonally and spatially-varied diet, including fish, invertebrates, mammals, and birds of 120 species or genera from 37 taxonomic orders and 62 families. The Hood Canal, Oregon-Washington Coastal, and Southern Puget Sound Stocks of Harbor Seals were well-represented. Salmonids were detected in 13.3% of samples collected in Oregon, 27.8% in Washington, and 23.74% of samples overall. The large variety of prey species and regional differences are reflective of opportunistic foraging behavior in Harbor Seals. This paper summarizes findings for this comprehensive assessment of Harbor Seal dietary composition in the northern CCLME.

The Oregon Spotted Frog (Rana pretiosa) is endemic to the Pacific Northwest and was recently listed as threatened under the Endangered Species Act. We tested the hypothesis that reproductive or physiological stress and parasitic disease may be contributing to the decline of this species. We histologically examined gonads and kidneys of newly metamorphosed wild-caught R. pretiosa to confirm sex and search for evidence of abnormal reproductive development and parasites. A subset of these specimens were also cleared and stained for examination of their skeletal morphology to identify potential skeletal malformations. The sex ratio did not differ significantly from 1:1, and we found no skeletal abnormalities. Trematode metacercarial parasites were present in the kidneys of all Spotted Frogs examined. We also report, for the first time, oocytes developing in the testes of 5 out of the 11 newly metamorphosed male Spotted Frogs examined. Further study into gonadal development of this species is necessary to investigate the significance of testicular oocytes in developing R. pretiosa and to identify whether these gonadal abnormalities are related in any way to their decline.

Males of most anuran species use acoustic communication to attract females. Rana aurora (Northern Red-legged Frog) is one of a few anuran species that calls underwater, making it difficult to survey using traditional visual and auditory methods. R. aurora are experiencing significant population declines and are listed as a sensitive species in Oregon. Lack of information on basic life-history strategies may limit conservation efforts. This study explored calling behavior and breeding phenology of R. aurora by quantifying seasonal and diel calling patterns. An audio recorder with an underwater microphone (called a hydrophone) was used to capture underwater vocalizations at Finley National Wildlife Refuge near Corvallis, Oregon, USA. Results suggest that male R. aurora chorus from January until March for up to 14 h per day at a time. This is a significantly longer duration than previously recorded. This study shows that passive acoustic surveys can improve the detection and monitoring of a cryptic species, which allows for better monitoring and surveying of this species.

The Millicoma Dace Rhinichthys cataractae is a form of Longnose Dace endemic to the Coos River drainage in southwestern Oregon. Sparse species records in the Oregon State University Ichthyology Collection and database and infrequent recent encounters prompted surveys to assess the current status and distribution of the species. In 2014, we surveyed locations that had historically supported Millicoma Dace using backpack electrofishing to describe their current distribution and abundance at these locations. In 2015, we extended these surveys further upstream in the South Coos River basin, outside of the documented historical range. We used an N-mixture model to estimate abundance and capture probability for Millicoma Dace at each sampling location. We evaluated the effects of habitat covariates on both capture probability and abundance at each sample site. We found Millicoma Dace were widespread throughout their historical range and in the South Coos River sites outside of their documented historical range. We only found Millicoma Dace associated with native fishes; we did not collect any nonnative fish during our surveys. We collected Millicoma Dace exclusively from swift-water habitats, which were relatively uncommon in the basin, and found them typically associated with cobble or boulder substrates. Millicoma Dace were most abundant in the South Fork Coos and West Fork Millicoma River subbasins. We estimated capture probabilities for Millicoma Dace ranging from 9% when substrate was dominated by bedrock to 28% when substrate was dominated by cobble or gravel. Abundance estimates ranged from 1 to 560 dace per sampling location with a total estimated abundance (sum of site estimates) of over 3200 dace for the sites we sampled.

Little work has focused on species presence, distributions, and habitat use of bats in the Great Plains of North America. In particular, no previous study has attempted to determine if bats are utilizing hibernacula during the winter months in North Dakota. The current lack of information regarding bat species presence during the winter months in North Dakota can have great conservation implications. Pseudogymnoascus destructans, the fungal pathogen responsible for white-nose syndrome (WNS) in bats across the United States and Canada, has led to great concern for wildlife managers. For many of the areas where WNS is present, information about the presence and location of hibernacula are known, allowing for close monitoring of the spread of the disease. However, some locations within the predicted path of WNS still lack information as to bat species presence during the winter months. Due to mortality rates sometimes reaching upwards of 100% as a result of WNS infection, filling in these information gaps is critical for conservation research. The purpose of this study was to determine if the badlands region of North Dakota supports over-wintering bat communities, document both utilized and potential hibernacula, and develop a Geographic Information Systems model in the program MaxEnt to be used for future studies and wildlife managers. Six species were positively identified in the badlands region of North Dakota during the pre-hibernation and winter hibernation periods: Big Brown Bat (Eptesicus fuscus), Silver-haired Bat (Lasionycteris noctivagans), Little Brown Bat (Myotis lucifugus), Long-eared Myotis (Myotis evotis), Townsend's Big-eared Bat (Corynorhinus townsendii), and Western Small-footed Myotis (Myotis ciliolabrum). Habitat suitability modeling was employed to model potential hibernacula in the study area. Knowledge of these potential hibernacula could be of great importance to wildlife managers, and results from this study may be used by regional wildlife managers to develop strategies for curtailing the spread of this disease into North Dakota.

After accounting for body size, bats have the longest lifespan of all mammals. Little Brown Bats (Myotis lucifugus) are one of the most common and widely distributed mammals in Canada; however, little is known of their longevity. We captured bats in Cypress Hills Interprovincial Park, Saskatchewan in May 2015, as part of long-term bat research in the Park that began in 1991. On 31 May 2015, we captured 16 female Little Brown Bats in a maternity colony, including a bat that was originally captured and banded as an adult in 1993. This capture record indicates that the female bat was at least 23 y old and this record represents the oldest bat record in Saskatchewan. Little Brown Bats in eastern North America have declined dramatically due to white-nose syndrome, a fungal disease responsible for the quickest wildlife die-off in history. Pre-infection natural history data for Little Brown Bats are important as the disease spreads through central Canada.

This study documents the seasonal fine-scale distribution, species richness, and abundance of subtidal fish species inhabiting sandy-bottom habitats in areas adjacent to Humboldt Bay, California. In total, 3 sampling areas, 2 located 5-km offshore, and 1 located 1-km offshore, were sampled quarterly for 1 y. Flatfish species (families Pleuronectidae and Bothidae) were the most common finfish sampled, although seasonal and spatial patterns varied among individual species. For instance, the abundance and size of English Sole (Parophrys vetulus) and Pacific Sanddab (Citharichthys sordidus) varied across both seasons and sampling areas, which may be attributed to their ontogenetic migration to offshore adult habitat. Species such as Starry Flounder (Platichthys stellatus) and Butter Sole (Isopsetta isolepis), did not vary seasonally, but did differ across sampling areas, likely as a function of depth. Although not the primary focus of our study, we include the abundance and diversity of invertebrates sampled, noting they far outnumbered finfish. Future research can use this study as a baseline to determine the temporal stability of these communities, and as a reference for comparative studies along the entire west coast.