Social Factors Key to Landscape-Scale Coastal Restoration: Lessons Learned from Three U.S. Case Studies

In the United States, extensive investments have been made to restore the ecological function and services of coastal marine habitats. Despite a growing body of science supporting coastal restoration, few studies have addressed the suite of societally enabling conditions that helped facilitate successful restoration and recovery efforts that occurred at meaningful ecological (i.e., ecosystem) scales, and where restoration efforts were sustained for longer (i.e., several years to decades) periods. Here, we examined three case studies involving large-scale and long-term restoration efforts including the seagrass restoration effort in Tampa Bay, Florida, the oyster restoration effort in the Chesapeake Bay in Maryland and Virginia, and the tidal marsh restoration effort in San Francisco Bay, California. The ecological systems and the specifics of the ecological restoration were not the focus of our study. Rather, we focused on the underlying social and political contexts of each case study and found common themes of the factors of restoration which appear to be important for maintaining support for large-scale restoration efforts. Four critical elements for sustaining public and/or political support for large-scale restoration include: (1) resources should be invested in building public support prior to significant investments into ecological restoration; (2) building political support provides a level of significance to the recovery planning efforts and creates motivation to set and achieve meaningful recovery goals; (3) recovery plans need to be science-based with clear, measurable goals that resonate with the public; and (4) the accountability of progress toward reaching goals needs to be communicated frequently and in a way that the general public comprehends. These conclusions may help other communities move away from repetitive, single, and seemingly unconnected restoration projects towards more large-scale, bigger impact, and coordinated restoration efforts

Genetic and environmental influences on the size-fecundity relationship in <i>Aedes albopictus</i> (Diptera: Culicidae): Impacts on population growth estimates?

<div><p>Population growth models are integral to ecological studies by providing estimates of population performance across space and time. Several models have been developed that estimate population growth through correlates of demographic traits, as measuring each parameter of the model can be prohibitive in experimental studies. Since differences in female size can accurately reflect changes in fecundity for many taxa, Livdahl and Sugihara developed a population growth index that incorporates size-fecundity relationships as a proxy for fecundity. To investigate the extent to which this model is robust to variation of this proxy, we tested if genetic (source population), temperature and resource treatments affect the size-fecundity relationship in <i>Aedes albopictus</i> (Skuse), the Asian tiger mosquito. We then determined if variation in the size-fecundity relationship alters the population growth estimates, lambda (λ<i>’</i>), when applied to Livdahl and Sugihara’s model. We performed 2 laboratory experiments in which we reared cohorts of four different geographic populations of <i>A</i>. <i>albopictus</i> across 5 temperature treatments (18, 21, 25, 18, 31°C) and three resource treatments (low, medium, high larval resources). We determined if the slope of the size-fecundity relationship varied by source population, temperature, or resource; and if variation in this relationship affects lambda (λ<i>’</i>) estimates in a competition study between <i>A</i>. <i>albopictus</i> and <i>Culex pipiens</i> (Linnaeus), the northern house mosquito. Temperature treatments significantly affected the size-fecundity relationship, resource level marginally affected the relationship, while source population had no effect. We found positive relationships between size and fecundity when mosquito larvae were reared at high temperatures and low resource levels but the relationship disappeared when mosquitoes were reared at a low temperature or with high levels of resources. The variation in the size-fecundity relationship produced from different temperatures resulted in statistically different lambda (λ<i>’</i>) estimates. However, these changes in lambda (λ<i>’</i>) did not alter the trends in the population performance across treatments or conclusions of the competition study. This study provides evidence that the population growth model is sensitive to variation in size-fecundity relationships and we recommend biologists apply the most compatible size-fecundity relationship to the models to obtain the most accurate estimates of population performance.</p></div

Data from: Rapid adaptation to novel climate at the northern range edge of the invasive Asian tiger mosquito Aedes albopictus: a moving target

1. Rapid adaptation in response to novel environments can facilitate species invasions and range expansions. Understanding how invasive disease vectors rapidly evolve to novel conditions—particularly at the edge of its non-native range—has important implications for mitigating the prevalence and spread of disease. 2. Here, we evaluate the role of local adaptation in overwintering capability of the Asian tiger mosquito, Aedes albopictus. This species invaded the Southern US in the 1980s and rapidly spread northward into novel climate compared to its native range. Photoperiodically induced egg diapause is a key trait contributing to the establishment and spread of Ae. albopictus in temperate latitudes, and diapause incidence rapidly developed a cline along a latitudinal gradient in the US shortly after its initial invasion. However, variation in overwintering survival of diapause-induced eggs along this gradient is not known, but is critical to the fitness-related role of diapause evolution in the establishment and spread of Ae. albopictus in its northern US range. 3. Using reciprocal transplants, we detected local adaptation in overwinter survival of diapausing Aedes albopictus eggs. In northern range-edge winters, eggs produced by range-edge individuals survived better than those produced by range-core individuals. Diapause eggs from range-edge and range-core locations survived equally well in range-core winters, and no eggs survived a winter beyond the current northern range limit in the US. 4. Synthesis and applications. These results demonstrate rapid (~ 3 decades) local adaptation of egg diapause, a key trait facilitating overwinter survival and range expansion for the invasive Asian tiger mosquito. In light of these results, control efforts could shift from targeting satellite populations to a focus on preventing dispersal into locally adapted, range-edge locations and to aim removal efforts towards areas surrounding locally adapted populations. Adopting new approaches to target rapidly adapting populations will require large-scale collaboration among control agencies and research institutions, and should begin in the northern US range to better control Ae. albopictus mosquito populations in the face of rapid adaptation

Light pollution disrupts circadian clock gene expression in two mosquito vectors during their overwintering dormancy

Abstract Artificial light at night (ALAN) is an increasingly important form of environmental disturbance as it alters Light:Dark cycles that regulate daily and seasonal changes in physiology and phenology. The Northern house mosquito (Culex pipiens) and the tiger mosquito (Aedes albopictus) enter an overwintering dormancy known as diapause that is cued by short days. These two species differ in diapause strategy: Cx. pipiens diapause as adult females while Ae. albopictus enter a maternally-programmed, egg diapause. Previous studies found that ALAN inhibits diapause in both species, but the mechanism is unknown. As the circadian clock is implicated in the regulation of diapause in many insects, we examined whether exposure to ALAN altered the daily expression of core circadian cloc genes (cycle, Clock, period, timeless, cryptochrome 1, cryptochrome 2, and Par domain protein 1) in these two species when reared under short-day, diapause-inducing conditions. We found that exposure to ALAN altered the abundance of several clock genes in adult females of both species, but that clock gene rhythmicity was maintained for most genes. ALAN also had little effect on clock gene abundance in mature oocytes that were dissected from female Ae. albopictus that were reared under short day conditions. Our findings indicate that ALAN may inhibit diapause initiation through the circadian clock in two medically-important mosquitoes

Size-fecundity relationships across temperature and resource treatments.

<p>(A) Size-fecundity relationships of <i>A</i>. <i>albopictus</i> across temperature treatments (N = 360). (B) Size-fecundity relationships of <i>A</i>. <i>albopictus</i> across resource treatments (N = 386).</p

Temperature, resource, and population effects on the size-fecundity relationship.

<p>Temperature, resource, and population effects on the size-fecundity relationship.</p

Effect of size-fecundity relationships on population growth estimates.

<p>Mean lambda (λ’) estimates (± 1 standard error) for <i>A</i>. <i>albopictus</i> using the size-fecundity relationship <i>f</i>(<i>w</i>_<i>x</i>) applied in the previously published study [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0201465#pone.0201465.ref041" target="_blank">41</a>] and those obtained across temperature treatments in the current study. Different capital letters indicate different pairwise comparisons between the lambda (λ’) estimates derived from different size-fecundity relationships.</p

Size-fecundity relationships across populations.

<p>Size-fecundity relationships of <i>A</i>. <i>albopictus</i> across populations of all mosquitoes pooled together from both experiments (N = 746).</p

Size-fecundity relationships across cohorts.

<p>Size-fecundity relationships across cohorts.</p