Migration tracking reveals geographic variation in the vulnerability of a Nearctic-Neotropical migrant bird.

We compared the vulnerability of a Nearctic-Neotropical migrant (Swainson's Thrush, Catharus ustulatus) for three geographically-defined breeding populations in California by linking breeding and wintering regions, estimating migration distances, and quantifying relative forest loss. Using data from light-level geolocator and GPS tags, we found that breeding birds from the relatively robust coastal population in the San Francisco Bay area wintered predominantly in western Mexico (n = 18), whereas the far rarer breeding birds from two inland populations that occur near one another in the Sierra Nevada and southern Cascades mountain ranges migrated to farther wintering destinations, with birds from the Lassen region (n = 5) predominantly going to Central America and birds from the Tahoe region (n = 7) predominantly to South America. Landscape-level relative forest loss was greater in the breeding and wintering regions of the two Cascade-Sierra populations than those of coastal birds.

Carbon sequestration in riparian forests: A global synthesis and meta-analysis.

Restoration of deforested and degraded landscapes is a globally recognized strategy to sequester carbon, improve ecological integrity, conserve biodiversity, and provide additional benefits to human health and well-being. Investment in riparian forest restoration has received relatively little attention, in part due to their relatively small spatial extent. Yet, riparian forest restoration may be a particularly valuable strategy because riparian forests have the potential for rapid carbon sequestration, are hotspots of biodiversity, and provide numerous valuable ecosystem services.

Shifting Effects of Ocean Conditions on Survival and Breeding Probability of a Long-Lived Seabird.

With a rapidly changing climate, there is an increasing need to predict how species will respond to changes in the physical environment. One approach is to use historic data to estimate the past influence of environmental variation on important demographic parameters and then use these relationships to project the abundance of a population or species under future climate scenarios. However, as novel climate conditions emerge, novel species responses may also appear.

Dependent vs. independent juvenile survival: contrasting drivers of variation and the buffering effect of parental care.

Juvenile survival is often found to be more sensitive than adult survival to variation in environmental conditions, and variation in juvenile survival can have significant impacts on population growth rates and viability. Therefore, understanding the population-level effects of environmental changes requires understanding the effects on juvenile survival. We hypothesized that parental care will buffer the survival of dependent juveniles from variation in environmental conditions, while the survival of independent juveniles will respond more strongly to environmental variation and, in turn, drive the overall variation in annual juvenile survival.

Projecting demographic responses to climate change: adult and juvenile survival respond differently to direct and indirect effects of weather in a passerine population.

Few studies have quantitatively projected changes in demography in response to climate change, yet doing so can provide important insights into the processes that may lead to population declines and changes in species distributions. Using a long-term mark-recapture data set, we examined the influence of multiple direct and indirect effects of weather on adult and juvenile survival for a population of Song Sparrows (Melospiza melodia) in California. We found evidence for a positive, direct effect of winter temperature on adult survival, and a positive, indirect effect of prior rainy season precipitation on juvenile survival, which was consistent with an effect of precipitation on food availability during the breeding season.