Development of community of practice to support quantitative risk assessment for synthetic biology products: contaminant bioremediation and invasive carp control as cases

Synthetic biology has the potential for a broad array of applications. However, realization of this potential is challenged by the paucity of relevant data for conventional risk assessment protocols, a limitation due to to the relative nascence of the field, as well as the poorly characterized and prioritized hazard, exposure, and dose–response considerations associated with the development and use of synthetic biology-derived organisms. Where quantitative risk assessment approaches are necessarily to fulfill regulatory requirements for review of products containing genetically modified organisms, this paper reviews one potential avenue for early-stage quantitative risk assessment for biosafety considerations of synthetic biology organism deployment into the environment. Building from discussion from a March 2018 US Army Engineer Research and Development Center workshop on developing such quantitative risk assessment for synthetic biology, this paper reviews the findings and discussion of workshop participants. This paper concludes that, while synthetic biology risk assessment and governance will continue to refine and develop in the coming years, a quantitative framework that builds from existing practice is one potentially beneficial option for risk assessors that must contend with the technology’s limited hazard characterization or exposure assessment considerations in the near term.     

Reframing the concept of alternative livelihoods

Alternative livelihood project (ALP) is a widely used term for interventions that aim to reduce the prevalence of activities deemed to be environmentally damaging by substituting them with lower impact livelihood activities that provide at least equivalent benefits. ALPs are widely implemented in conservation, but in 2012, an International Union for Conservation of Nature resolution called for a critical review of such projects based on concern that their effectiveness was unproven. We focused on the conceptual design of ALPs by considering their underlying assumptions. We placed ALPs within a broad category of livelihood‐focused interventions to better understand their role in conservation and their intended impacts. We dissected 3 flawed assumptions about ALPs based on the notions of substitution, the homogenous community, and impact scalability. Interventions based on flawed assumptions about people's needs, aspirations, and the factors that influence livelihood choice are unlikely to achieve conservation objectives. We therefore recommend use of a sustainable livelihoods approach to understand the role and function of environmentally damaging behaviors within livelihood strategies; differentiate between households in a community that have the greatest environmental impact and those most vulnerable to resource access restrictions to improve intervention targeting; and learn more about the social–ecological system within which household livelihood strategies are embedded. Rather than using livelihood‐focused interventions as a direct behavior‐change tool, it may be more appropriate to focus on either enhancing the existing livelihood strategies of those most vulnerable to conservation‐imposed resource access restrictions or on use of livelihood‐focused interventions that establish a clear link to conservation as a means of building good community relations. However, we recommend that the term ALP be replaced by the broader term livelihood‐focused intervention. This avoids the implicit assumption that alternatives can fully substitute for natural resource‐based livelihood activities.     

Long-term behavior at foraging sites of adult female loggerhead sea turtles (Caretta caretta) from three Florida rookeries

We used satellite telemetry to study behavior at foraging sites of 40 adult female loggerhead sea turtles (Caretta caretta) from three Florida (USA) rookeries. Foraging sites were located in four countries (USA, Mexico, the Bahamas, and Cuba). We were able to determine home range for 32 of the loggerheads. One turtle moved through several temporary residence areas, but the rest had a primary residence area in which they spent all or most of their time (usually >11 months per year). Twenty-four had a primary residence area that was <500 km² (mean = 191). Seven had a primary residence area that was ≥500 km² (range = 573–1,907). Primary residence areas were mostly restricted to depths <100 m. Loggerheads appeared to favor areas with larger-grained sediment (gravel and rock) over areas with smaller-grained sediment (mud). Short-term departures from primary residence areas were either looping excursions, typically involving 1–2 weeks of continuous travel, or movement to a secondary residence area where turtles spent 25–45 days before returning to their primary residence area. Ten turtles had a secondary residence area, and six used it as an overwintering site. For those six turtles, the primary residence area was in shallow water (<17 m) in the northern half of the Gulf of Mexico (GOM), and overwintering sites were farther offshore or farther south. We documented long winter dive times (>4 h) for the first time in the GOM. Characterizing behaviors at foraging sites helps inform and assess loggerhead recovery efforts.     

Passive acoustic monitoring of the decline of Mexico's critically endangered vaquita

The vaquita (Phocoena sinus) is the world's most endangered marine mammal with approximately 245 individuals remaining in 2008. This species of porpoise is endemic to the northern Gulf of California, Mexico, and historically the population has declined because of unsustainable bycatch in gillnets. An illegal gillnet fishery for an endangered fish, the totoaba (Totoaba macdonaldi), has recently resurged throughout the vaquita's range. The secretive but lucrative wildlife trade with China for totoaba swim bladders has probably increased vaquita bycatch mortality by an unknown amount. Precise population monitoring by visual surveys is difficult because vaquitas are inherently hard to see and have now become so rare that sighting rates are very low. However, their echolocation clicks can be identified readily on specialized acoustic detectors. Acoustic detections on an array of 46 moored detectors indicated vaquita acoustic activity declined by 80% between 2011 and 2015 in the central part of the species’ range. Statistical models estimated an annual rate of decline of 34% (95% Bayesian credible interval –48% to –21%). Based on results from 2011 to 2014, the government of Mexico enacted and is enforcing an emergency 2‐year ban on gillnets throughout the species’ range to prevent extinction, at a cost of US$74 million to compensate fishers. Developing precise acoustic monitoring methods proved critical to exposing the severity of vaquitas’ decline and emphasizes the need for continual monitoring to effectively manage critically endangered species.     

Boldness is influenced by sublethal interactions with predators and is associated with successful harem infiltration in Madagascar hissing cockroaches

One of the contemporary challenges of the behavioral syndromes literature is to identify how individual variation in behavior is determined, and whether this variation impacts ecological success. Although variation in experience is an obvious potential driver of intraspecific behavioral variation, predicting the impact of experience on suites of correlated behavioral traits is less intuitive. Specifically, if experience impacts traits that shape individuals' success in multiple contexts (e.g., foraging and anti-predator behavior), then experience could generate cross-contextual performance trade-offs associated with behavioral spillover. In the present study, we explore how sublethal experience with predators impacts various aspects of male behavioral tendencies in the Madagascar hissing cockroach, Gromphadorhina portentosa. First, we found that males' activity level and boldness were correlated together in the form of a behavioral syndrome. Second, we found that repeated sublethal interactions with predators shifted male boldness but not activity level, thus suggesting that the syndrome's constituent traits can respond to experience at least semi-independently. Third, we discovered that although predator exposure only influenced boldness, we found that boldness was highly correlated with males' ability to obtain rewarding positions in the harems of rival males. Taken together, our data suggest (but do not yet confirm) that although sublethal exposure to predators influences only a narrow subset of male's behavioral tendencies, these effects could still have nonintuitive consequences for males' success in functionally dissimilar ecological contexts (i.e., social and sexual encounters).