Protected fish spawning aggregations as self-replenishing reservoirs for regional recovery.

Dispersal of eggs and larvae from spawning sites is critical to the population dynamics and conservation of marine fishes. For overfished species like critically endangered Nassau grouper (Epinephelus striatus), recovery depends on the fate of eggs spawned at the few remaining aggregation sites. Biophysical models can predict larval dispersal, yet these rely on assumed values of key parameters, such as diffusion and mortality rates, which have historically been difficult or impossible to estimate. We used in situ imaging to record three-dimensional positions of individual eggs and larvae in proximity to oceanographic drifters released into egg plumes from the largest known Nassau grouper spawning aggregation. We then estimated a diffusion-mortality model and applied it to previous years' drifter tracks to evaluate the possibility of retention versus export to nearby sites within 5 days of spawning. Results indicate that larvae were retained locally in 2011 and 2017, with 2011 recruitment being a substantial driver of population recovery on Little Cayman. Export to a nearby island with a depleted population occurred in 2016. After two decades of protection, the population appears to be self-replenishing but also capable of seeding recruitment in the region, supporting calls to incorporate spawning aggregation protections into fisheries management.

Recovery of critically endangered Nassau grouper (Epinephelus striatus) in the Cayman Islands following targeted conservation actions.

Many large-bodied marine fishes that form spawning aggregations, such as the Nassau grouper (Epinephelus striatus), have suffered regional overfishing due to exploitation during spawning. In response, marine resource managers in many locations have established marine protected areas or seasonal closures to recover these overfished stocks. The challenge in assessing management effectiveness lies largely in the development of accurate estimates to track stock size through time. For the past 15 y, the Cayman Islands government has taken a series of management actions aimed at recovering collapsed stocks of Nassau grouper. Importantly, the government also partnered with academic and nonprofit organizations to establish a research and monitoring program (Grouper Moon) aimed at documenting the impacts of conservation action. Here, we develop an integrated population model of 2 Cayman Nassau grouper stocks based on both diver-collected mark-resight observations and video censuses. Using both data types across multiple years, we fit parameters for a state-space model for population growth. We show that over the last 15 y the Nassau grouper population on Little Cayman has more than tripled in response to conservation efforts. Census data from Cayman Brac, while more sparse, show a similar pattern. These findings demonstrate that spatial and seasonal closures aimed at rebuilding aggregation-based fisheries can foster conservation success.

Association Between Nonmodifiable Demographic Factors and Patient Satisfaction Scores in Spine Surgery Clinics.

The Press Ganey survey is the most widely used instrument for measuring patient satisfaction. Understanding the factors that influence these surveys may permit better use of survey results and may direct interventions to increase patient satisfaction. Press Ganey Clinician and Group Consumer Assessment of Healthcare Providers and Systems surveys administered to ambulatory spine surgery clinic patients within a large tertiary care network from May 2016 to September 2017 were retrospectively reviewed. Mean comparison testing was performed to measure associations between patient demographics and responses to "overall provider rating" and "recommend this provider's office" survey questions. Mean difference to achieve significance was set at α<0.05. A multivariate analysis was performed to determine independent factors. A total of 1400 survey responses from the offices of 11 orthopedic spine surgeons were included. Patients 18 to 34 years old had significantly lower responses to the overall provider rating question than older patients (P<.001), and increasing patient age was correlated with improved ratings. Highest education level was inversely correlated with satisfaction scores, with patients who had attained graduate level education having the lowest satisfaction scores (P=.001). Those with commercial insurance had significantly lower ratings for recommend this provider's office (P=.042) and overall provider rating (P=.022) questions than those with other insurance types. Patients administered the survey on paper had significantly lower ratings than those administered the survey online (P=.006). Provider ratings were significantly higher when the sex and ethnicity of the patient were concordant with the provider (P=.021). This study showed that independent, nonmodifiable factors such as age, education level, and survey mode were significantly associated with the satisfaction of ambulatory spine surgery clinic patients. [Orthopedics. 2019; 42(3):143-148.].