Physiological Correlates of Urbanization in a Desert Songbird

Rapid worldwide urbanization is creating novel environments to which animals must adapt, a topic of growing interest for biologists. Studies of how organisms are affected by cities historically centered on large-scale censusing of populations, but recent investigations have considered finer-scaled, urban-rural differences among individuals and species in their behavior, morphology, and physiology, specifically as they relate to urban stress. A number of factors (e.g., corticosterone (CORT)-related stress response) may contribute to the degree of stress experienced by animals living under urban versus natural conditions, but several physiological variables have yet to be considered together in a large-scale assessment. Here, in a widespread species of desert passerine (the house finch, Haemorhous mexicanus), we quantified variation in plasma oxidative stress, plasma concentrations of vitamins and carotenoids, and body-mass of males in three successive seasons (winter, spring, and late summer/early fall) along an urban-rural gradient in Phoenix, Arizona, USA. We found that degree of urbanization was: (1) negatively related to circulating vitamin A concentrations in winter, (2) positively correlated with body-mass during spring, and (3) negatively associated with plasma concentrations of two carotenoids: zeaxanthin (during breeding) and 3-hydroxy-echinenone (3HE) (during molting). The striking link between 3HE levels and urbanization is consistent with previous research showing that urban songbirds have lower carotenoid levels and faded plumage; our finding is the first to implicate specific effects on a metabolically derived carotenoid for coloration. The fact that we observed only season-specific links between urbanization and indicators of quality in finches suggests that (at least for these metrics) there are no strong, lasting urban pressures imposed on finch physiology over the year. Interestingly, we found that a metric of plasma oxidative stress (lipid peroxidation) was positively correlated with levels of two carotenoids (lutein during breeding and 3HE during molting), which is consistent with a prior study of ours showing that finches with redder plumage deposit higher levels of CORT in their feathers; taken together, our studies suggest complex associations between carotenoids and stres

The effects of sun exposure on carotenoid accumulation and oxidative stress in the retina of the House Finch (Haemorhous mexicanus)

Additional file 1: Tables S1–8. Detailed data tables from each of the experimental comparisons

Intensive Cultural Resources Survey Of The Proposed Wurzbach Parkway Extension Project From Blanco Road To Wetmore Road, Bexar County, Texas

SWCA Environmental Consultants (SWCA) conducted an intensive cultural resources survey on behalf of the Texas Department of Transportation (TxDOT), of the proposed Wurzbach Parkway Extension Project in San Antonio, Texas. TxDOT proposes to extend the existing Wurzbach Parkway approximately 5.3 miles between Farm-to-Market Road (FM) 2696 (Blanco Road) and Wetmore Road. The undertaking involves the new construction of a four-lane divided roadway within an approximately 250-foot right-of-way (ROW) that is state-owned property. Overall, the Area of Potential Effects (APE) is 27,984 feet long, 250 feet wide, and maximally 10 feet deep. Additionally, the APE covers roughly 51.77 acres of permanent and temporary easements. SWCA’s investigations of the Wurzbach Parkway Extension Project APE included a background review, and an intensive pedestrian survey with shovel testing and backhoe trenching of selected areas within the APE. The background literature review determined that 21 surveys of varying magnitude have been conducted within or adjacent to the APE. These surveys are related to roadway construction or expansion, as well as park development. Fourteen archaeological sites have been documented within or adjacent to the APE and 44 additional archaeological sites have been previously recorded within 1 mile of it. The APE traverses a portion of the Walker Ranch National Register District, but the undertaking does not affect any contributing resources besides those that were previously mitigated by TxDOT in the 1990s. SWCA archaeologists conducted field investigations within the Wurzbach Parkway Extension Project APE between May 1 and June 21, 2007. The pedestrian survey established that the majority of the APE has been disturbed by previous residential, commercial, and dam construction. Of the 14 previously recorded sites within or immediately adjacent to the APE, seven were determined during the current survey not to extend into the APE (41BX181, 41BX183, 41BX194, 41BX203, 41BX209, 41BX222, and 41BX223). Two of the seven sites within the APE had been successfully mitigated through prior data recovery efforts (41BX184 and 41BX228), while landforms associated with site 41BX202 were found to have been completely destroyed. Current investigations included a reconnaissance survey of site 41BX949, shovel testing at site 41BX948, and backhoe trenching at site 41BX947. Right of entry was denied at two properties, including the Coker United Methodist Church, which precluded a revisit to 41BX1062. The portions of sites 41BX184, 4BX202, 41BX228, and 41BX949 that remain in the Wurzbach Parkway Extension Project APE are not considered eligible for inclusion to the National Register of Historic Places (NRHP) or for designation as a State Archeological Landmark (SAL); therefore, SWCA recommends no further work at these sites. Survey-level excavations at 41BX947 and 41BX948 revealed no cultural materials, temporally diagnostic artifacts, features, or intact buried deposits. Thus, 41BX947 and 41BX948 have little to no research value. As such, neither 41BX947 nor 41BX948 is considered significant or eligible for inclusion in the NRHP or for designation as an SAL. Based on the extent of previous investigations and the results of the current survey, SWCA recommends no additional archaeological investigations for 41BX184, 4BX202, 41BX228, 41BX947, 41BX948, 41BX949, and 41BX1062. Subsequent to the SWCA survey, TxDOT conducted an impact evaluation of the additional 51.77 acres of easements associated with the project. No cultural resources were documented as part of this effort. This TxDOT work was submitted with the SWCA draft report to the Texas Historical Commission (THC) who concurred with the findings in both reports. This report combines the results of both investigations into a final report to satisfy the Texas Antiquities Code (TAC) permit requirements. In accordance with Section 106, 36 Code of Federal Regulations (CFR) 800.4, SWCA and TxDOT have made a reasonable and good faith effort to identify archaeological historic properties within the APE. As no properties were identified that meet the criteria for listing on the NRHP according to 36 CFR 60.4 or for designation as an SAL according to 13 TAC 26.12, no archeological historic properties are affected and SWCA recommends no further work for the 5.3-mile Wurzbach Parkway Extension Project APE. Artifacts were collected as part of the undertaking and will be curated at the Texas Archeological Research Laboratory

Positive Carotenoid Balance Correlates with Greater Reproductive Performance in a Wild Bird

Background: Carotenoids can confer somatic and reproductive benefits, but most evidence is from captive animal experimentation or single time-point sampling. Another perhaps more informative means by which to assess physiological contributions to animal performance is by tracking an individual’s ability to increase or sustain carotenoids or other health-related molecules over time, as these are likely to be temporally variable. Methodology/Principal Findings: In a field study of North American barn swallows (Hirundo rustica erythrogaster), we analyzed within-individual changes in carotenoid concentrations by repeatedly sampling the carotenoid profiles of individuals over the course of the breeding season. Our results demonstrate that carotenoid concentrations of individuals are temporally dynamic and that season-long balance of these molecules, rather than single time-point samples, predict reproductive performance. This was true even when controlling for two important variables associated with reproductive outcomes: (1) timing of breeding and (2) sexually selected plumage coloration, which is itself positively correlated with and concomitantly changes with circulating carotenoid concentrations. Conclusions/Significance: While reproduction itself is purported to impose health stress on organisms, these data suggest that free-ranging, high-quality individuals can mitigate such costs, by one or several genetic, environmental (diet), or physiological mechanisms. Moreover, the temporal variations in both health-linked physiological measures and morphological traits we uncover here merit further examination in other species, especially when goals include the estimation of signal information content or the costs of trait expression