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The article focuses on listing the lifetime members of the Society for Northwestern Vertebrate Biology.

The endangered Sonoma County population of the California Tiger Salamander, Ambystoma californiense, undergoes migrations between breeding pools and upland dry-season refugia. Orientation in this species during breeding migrations has been addressed minimally in previous studies, and literature is particularly sparse concerning newly metamorphosed juveniles. Previous works have not addressed the ability of metamorphs to orient or the way in which they search for upland refugia. The initial migration from natal pools to uplands following metamorphosis has been identified as a crucial life-history juncture for the persistence of this species. We evaluated fine-scale movements of newly metamorphosed California Tiger Salamanders as they moved away from breeding pools by capturing salamanders with a drift fence and then tracking individuals with fluorescent powder. Here we show that newly metamorphosed juveniles do not move randomly, and that they can re-orient to their upland migration after being interrupted and disoriented. Further, we demonstrate that while searching for burrow refugia, metamorph movement can be characterized as a correlated random walk. [ABSTRACT FROM AUTHOR]

Population studies of diminutive species often present unique challenges associated with methods of identifying individuals in a manner that can be reliable and retained over long periods of time. Small snakes present even more difficulties, as many marking methods rely on the use of either invasive implantation of devices, such as passive integrated transponder (PIT) tags, or through mutilation such as branding or scale clipping. Here I present an alternative method by utilizing a flatbed scanner to obtain consistent images of sufficient quality for use in photographic identification of the Common Sharp-tailed Snake (Contia tenuis) using the unique individual pigmentation patterns on the venter of the head. Additionally, I show that HotSpotter© software consistently scored image pairs of known and assessed matches higher than between pairs of known and assessed mismatches using the flatbed scanner imagery. This method provides a repeatable, reliable, non-invasive, and non-mutilating alternative to more traditional methods of identifying individual snakes. [ABSTRACT FROM AUTHOR]

The Northwestern Pond Turtle (Actinemys marmorata) ranges from Washington to the southern end of the Central Valley of California. Because of the extensive latitudinal range of the species, it is expected that several life-history traits will vary across the range. Most data on population structure and growth of A. marmorata have been gathered from southern Oregon and California, and reproductive data are sparse north of the southern end of the range. These data are important to a critical understanding of the species' biology and especially for making conservation judgments for a species some consider in need of protection. Thus, we collected key life-history information at the Luckiamute State Natural Area in the mid-Willamette Valley, Oregon. We found that the population structure, adult size, and growth were similar to southern Oregon sites. Clutch size from radiographs was 6.0 ± 1.18 SE (range = 5–8), smaller than sites at the southern end of the range. The slow growth rate of Luckiamute turtles may be explained by cooler temperature in the Willamette Valley compared to more southerly sites. Still, Luckiamute adults reach a slightly larger size than most turtles in more southerly sites. It just requires many more years to reach sexual maturity and achieve larger sizes in northern areas. [ABSTRACT FROM AUTHOR]

Understanding parasite transmission in communities requires knowledge of each species' capacity to support transmission. This property, 'competence', is a critical currency for modelling transmission under community change and for testing diversity–disease theory. Despite the central role of competence in disease ecology, we lack a clear understanding of the factors that generate competence and drive its variation.We developed novel conceptual and quantitative approaches to systematically quantify competence for a multi‐host, multi‐parasite community. We applied our framework to an extensive dataset: five amphibian host species exposed to four parasitic trematode species across five ecologically realistic exposure doses. Together, this experimental design captured 20 host–parasite interactions while integrating important information on variation in parasite exposure. Using experimental infection assays, we measured multiple components of the infection process and combined them to produce competence estimates for each interaction.With directly estimated competence values, we asked which components of the infection process best explained variation in competence: barrier resistance (the initial fraction of administered parasites blocked from infecting a host), internal clearance (the fraction of established parasites lost over time) or pre‐transmission mortality (the probability of host death prior to transmission). We found that variation in competence among the 20 interactions was best explained by differences in barrier resistance and pre‐transmission mortality, underscoring the importance of host resistance and parasite pathogenicity in shaping competence.We also produced dose‐integrated estimates of competence that incorporated natural variation in exposure to address questions on the basis and extent of variation in competence. We found strong signals that host species identity shaped competence variation (as opposed to parasite species identity). While variation in infection outcomes across hosts, parasites, individuals and doses was considerable, individual heterogeneity was limited compared to among‐species differences. This finding highlights the robustness of our competence estimates and suggests that species‐level values may be strong predictors for community‐level transmission in natural systems.Competence emerges from distinct underlying processes and can have strong species‐level characteristics; thus, this property has great potential for linking mechanisms of infection to epidemiological patterns. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]